- Email: [email protected]
Forces of Commonly Used Chiropractic Techniques for Children: A Review of the Literature
Forces of Commonly Used Chiropractic Techniques for Children: A Review of the Literature Angela J. Todd, BAppSc(Chiro), Grad Dip(Chiro Pediatrics), a
Matthew T. Carroll, PhD, b and Eleanor K.L. Mitchell, PhD c, d ABSTRACT Objective: The purpose of this study is to review the available literature that describes forces of the most commonly used chiropractic techniques for children. Methods: Review of the English-language literature using search terms Chiropract* and technique, protocol, or approach in databases PubMed, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine, and Index to Chiropractic Literature and direct contact with authors of articles and book chapters. Results: Eleven articles that discussed the 7 most commonly used pediatric chiropractic techniques and the forces applied were identified. Chiropractic techniques reviewed described forces that were modified based on the age of the patient. Force data for mechanically assisted devices were varied, with the minimum force settings for some devices outside the age-specific safe range recommended in the literature when not modified in some way. Conclusion: This review found that technique selection and application by chiropractors treating infants and young children are typically modified in force and speed to suit the age and development of the child. (J Manipulative Physiol Ther 2016;xx:1-10) Key Indexing Terms: Chiropractic Manipulation; Children; Review of Literature
INTRODUCTION More than 30 million child visits to doctors of chiropractic occur in the United States every year. 1 It is estimated that more than 19.1 million chiropractic visits occur in Australia annually 2 and other studies estimate that 8.6% of all visits are from children. 3 By combining these two studies findings, we can estimate that in excess of 1.6 million child visits occur in Australia every year. Given this estimate, the published cases of serious adverse events in infants and children receiving chiropractic or other types of manual therapy are exceedingly rare, 4–6 and there have been no cases of death associated with chiropractic care of a
Private Practice, Sale, Australia. School of Rural Health–Churchill, Monash University, Churchill, Australia. c Department of Rural and Indigenous Health, School of Rural Health, Monash University, Moe, Australia. d School of Rural Health–East Gippsland, Monash University, Bairnsdale, Australia. Submit requests for reprints to: Angela J. Todd, BAppSc(Chiro), Grad Dip(Chiro Pediatrics), Private Practice, PO Box 1500, Sale, VIC 3850, Australia. (e-mail: [email protected]). Paper submitted November 17, 2014; in revised form June 11, 2015; accepted June 15, 2015. 0161-4754 © 2016 by National University of Health Sciences. http://dx.doi.org/10.1016/j.jmpt.2016.05.006 b
children reported in the academic literature to date. 4–6 Nonetheless, studies of the amount of force used on children for safety purposes should still be considered. In Australia and the United States, chiropractic students undertake extensive theoretical and practical training at the university level, including study of and experience with the pediatric population. 7 Chiropractors are trained to perform a thorough history and examination to determine whether chiropractic care is appropriate and identify a suitable technique, given the age and neurologic presentation of the child. Chiropractors have a range of techniques available to them and can modify these to suit the age and condition of the patient. The process of selecting one type of chiropractic technique over another is based on many factors, including the techniques the practitioner is clinically experienced in applying and the perceived effectiveness of each, as well as the practitioner's understanding of the biological plausibility of using a particular therapy and the associated research evidence base. 8 It should be noted that health professionals of all types face the same considerations when determining appropriate treatment approaches. 9–11 Data from the National Board of Chiropractic Examiners identified that three-quarters of chiropractors use traditional styles of chiropractic spinal manipulation (diversified or Gonstead technique) and more than half use an Activator instrument or the sacro-occcipital technique (SOT). 12 Although these data are not age specific, a 2010 cross-sectional
2
Todd et al Forces of Chiropractic Techniques on Children
survey of 135 chiropractors with pediatric diplomate qualifications in the United States 13 revealed that reduced-force diversified technique (spinal manipulative technique that has been modified to be lower force and amplitude) was used by 59% of pediatric chiropractors; 63% reported using an Activator instrument, 59% a drop-section table, and 77% cranial therapy. In addition, this study found that cranial and Activator techniques were used mainly for children 5 years and younger, and that modified diversified, Activator, and drop-section table adjustments were used on older children. The Activator instrument, SOT, toggle, touch and hold, and modified spinal manipulative therapy (SMT) were typically used by chiropractors for restoring joint and neurologic function, 14 and particularly in children to reduce neck pain, back pain, and joint stiffness. 13 Given the diversity of styles of chiropractic manipulation, there are currently no peer-reviewed articles that review the amount of force used in commonly used pediatric manipulation techniques. Therefore, the purpose of this study is to review the available literature that describes forces of the most commonly used chiropractic techniques for children.
METHODS The academic literature was initially searched in PubMed, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine, and Index to Chiropractic Literature with a broad strategy, using the term chiropract* combined with the terms (technique OR protocol OR approach) in a “full-text” or “all-fields” search. All records published in English were screened for information about the force used in the application of any manual therapy technique. After initial removal of duplicates, practice guidelines, and non–peer-reviewed items (eg, commentaries and letters), there were further exclusions, including case reports and articles where neither the title nor abstract indicated specific discussion of technique application. A second round of technique-specific searches was also conducted. The terms (force OR thrust) were combined in individual full-text or all-fields searches with each of “spinal manipulation,” “adjusting instrument,” (“sacro-occipital technique,” OR “craniosacral therapy”), “toggle,” “touch and hold,” and (“Thompson technique” OR “drop piece”). Records were screened as for the initial search (Fig 1). A manual review of the reference lists of included articles was undertaken along with contact with authors to identify articles that were more recent.
RESULTS The initial search captured 1796 potential articles, of which 54 full-text articles were reviewed. This search
Journal of Manipulative and Physiological Therapeutics Month 2016
identified 2 articles by Marchand, 15,16 which when references were hand searched yielded 3 more articles, by Koch et al 17,18 and Snodgrass et al. 19 Searching of the literature using technique-specific search terms resulted in the inclusion of a further 4 studies 16,20–22 and 1 textbook source, 23 with an additional in-press journal article yielding direct contact with the author 24 (Table 1).
Spinal Manipulative Therapy Spinal manipulation has been defined as the application of a precisely controlled high-velocity, low-amplitude (HVLA) thrust to a joint, causing tissue deformation of the spine and surrounding tissue. The thrust is designed to restore motion in the targeted joint by applying force to the area of segmental restricted motion. 15,26 Chiropractors in Europe were surveyed about their practice techniques for children, 25 resulting in the following guidelines for pediatric chiropractic, identifying 4 grades of therapeutic input for the application of pediatric SMT for different age groups 15: Grade 1: neonates and infants aged 0 to 2 months (low force, low speed) at 10% of estimated force for adults (equivalent to 11.2 N) Grade 2: infants and toddlers aged 3 to 23 months (low force, low speed) at 30% of estimated force for adults (equivalent to 33.6 N) Grade 3: young children aged 2 years to 8 years or younger (moderate force, moderate speed) at 50% of estimated adult force (equivalent to 56 N) Grade 4: older children and young adults aged 8 to 18 years (moderate force, high speed) at 80% of estimated adult force (equivalent to 89.6 N) A similar set of guidelines for different age groups has been developed by Marchand, 15 drawing on findings from an extensive study of tensile strength and osteoligamentous failure rates in pediatric spines as well as a report of transient bradycardia and apnea events that occurred with thrusts of 50 N to 70 N in infants younger than 3 months. 18 Marchand 15 has recommended that SMT be applied at a maximum cervical loading of 20 N for neonates, 50 N for children aged 2 to 23 months, 85 N for children aged 2 to 8 years, 135 N for 8- to 18-year-olds, and 155 N for adults to prevent possible adverse physiological reactions caused by any inappropriate level of force. The report of transient events occurring in infants as a result of thrusts in the 50 N to 70 N range comes from research measured by Koch and Girnus. 27 The measurements involved resting the force plate on the inside of the investigator's thigh (Fig 2c) in an attempt to simulate a manipulation on an infant, with the thrusts repeated 50 times. The range of forces was between 50 N and 70 N, with 1 outlier thrust of 30 N. No infants were involved in the measurement of these thrusts. The
Journal of Manipulative and Physiological Therapeutics Volume xx, Number
Todd et al Forces of Chiropractic Techniques on Children
Records identified through broad database search (n = 1796)
Records screened after duplicates, practice guidelines and non-peer reviewed items removed (n = 1045)
Full-text articles assessed for eligibility (n = 54)
Records Excluded after screening (n = 751)
Records Excluded (n = 991)
Full text articles excluded (no discussion of force) (n = 48)
Specific technique searches (n = 6)
Fig 1. Search results. investigators were both practitioners who used manipulation to the cervical spine of infants.
Activator Instrument The Activator instrument is a small handheld device designed by Arlan Fuhr in the early 1980s that delivers a measured thrust, with the force applied able to be modified by altering the instrument settings. 16 There are now 5 versions of the Activator instrument available, each with a different range of possible forces (Table 2). There have been 2 articles attempting to measure the forces applied by these and other instruments, with different measurement approaches resulting in different force readings (Fig 2). According to Colloca et al, 22 the mean minimum force applied by an Activator I is 61.5 N (Table 2), whereas the Activators II and III apply approximately 137.8 N and 128.2 N, respectively, and the Activator IV applies 123.1 N. 22 These values were measured by fixing the instruments to a stable surface and applying the tip directly to a metal force plate (Fig 2a). However, Liebschner et al 24 argue that the approach to applying and measuring force needs to be analogous to the way in which it is delivered to a human patient and so incorporated a range of polymorphous structures to replicate different levels of tissue stiffness in the human spine (Fig 2b). This use of a spinal analog resulted in notably lower-force recordings (Table 2).
The Activator V has recently become available and is a mechanically assisted handheld instrument that is battery powered (as opposed to the previous spring-loaded Activator versions). The minimum force applied with this instrument was measured with a soft polymorphous substance analogous to a flexible child spine at approximately 40 N. 24
Electrically Assisted Mechanical Adjusting Instruments Other instruments that deliver a mechanical force have also been developed. The Harrison Adjusting Instrument (HAI) and the Neuromuscular Impulse (NMI) both offer electrically assisted mechanical handheld measured thrusts. The HAI is reported to give a minimum thrust of about 45 N into a fixed force plate on a hard surface 22 (Table 2) and the NMI a minimum of 20 N onto a soft tissue analog 24 (Fig 2; Table 2). As stated earlier, the Activator V is also mechanically loaded and is battery powered with a minimal force setting into a soft tissue analog of 40 N.
Sacro-occipital Technique Sacro-occcipital technique is a whole-body approach to restoring neurologic function by normalizing tension in the fascia, muscles, spine, pelvis, and cranial joints and reducing tension along the dura. 28 Sacro-occcipital
3
4
Todd et al Forces of Chiropractic Techniques on Children
Journal of Manipulative and Physiological Therapeutics Month 2016
Table 1. Summary of Evidence: Forces Applied to Perform Pediatric Chiropractic Techniques Study Marchand
Study Details 25
Findings
Comment/s
Cross-sectional survey of 956 European 96.3% of surveyed chiropractors treated Estimation of forces applied in modified SMT based on survey data and not from chiropractors relating to technique usage, children with no severe adverse events. adverse events in various ages of children Most child patients were younger than 2 y or actual measurements on force plates older than 12 y. Forces same as adults for children 13-18 y (62.7% of respondents), speed was also same as adult (45% of respondents), cavitation same as an adult (42% of respondents). No specific of force or speed data for children younger than 2 y, in comparison to adult
Fuhr and Menke16
Narrative review of all Activator instrument The force and impulse energy of the literature N35 y up to and including 2003 Activator instrument allows this technique to produce the same results for patients as seen with manual spinal adjustment.
This article was missing more recent data provided by Liebschner et al24 on force profiles of the full range of Activator instruments.
Marchand15
A literature review of tensile strength of Proposed the following guidelines for the adult and pediatric spines maximum safe level of forces into the cervical spine from SMT for different age groups: • 20N, neonates • 50N, 3-23 mo • 85N, 3-8 y • 135N, 8-18 y
Tensile strength differences between pediatric and adult spines led to a model of care for safe application of pediatric SMT.
Koch et al18
Prospective clinical trial of 199 infants to investigate vegetative reactions after mechanical irritation of suboccipital region
Infants received upper cervical manual therapy from a medical manipulator. Thrusts reported to be in the 50-70 N range with apnea and flushing of skin observed in 50 infants
The estimation of applied force reported in this study was based on previous work by the authors (see next entry).
Koch and Girnus27
Repeated measurements of force applied with fingertip thrust (to approximate spinal manipulation of an infant) by 2 experienced chiropractors
Measure of 25 thrusts each into a force plate by 2 medical practitioners, simulating a medical manipulation on a child. Mean force applied for medical manipulation on a child of 50-70 N
Medical manipulation simulation on a force plate was higher than that estimated for modified manipulation by a chiropractor.25
Colloca et al22
Measurement of peak forces at each setting on the Activator instruments I, II, III, and IV. The HAI and NMI instruments were applied directly to a force plate.
The electrically assisted HAI and NMI produced the largest ranges between the highest and lowest settings and highest maximum peak force when compared with the spring-loaded Activator instruments. Forces recorded on stiff force plate on minimum settings ranged from 61 N to 137.8 N across Activator instruments and 44.9 N for HAI and 123.5 N for NMI.
The experimental set-up did not allow for measurements to approximate the actual force experienced at the joint, which is protected by tissue and some dampening by being held by the practitioner.
Liebschner et al24
Measurement of peak forces at the minimum and maximum setting on the Activator instruments II, IV, and V and the NMI. Instruments were applied to polymorphous substances (analogous to the spine and surrounding tissue) attached to a force plate. Instruments were tested in a fixed position and handheld.
The softer polymorphous substance reduced Activator instrument had lower minimal the force measured for each instrument, as forces than previously reported by did testing the instruments in a handheld Colloca et al.22 set-up. Forces for the variety of Activator instruments used at lowest setting ranged from 20 N to 40 N on soft tissue analog.
Zegarra-Parodi et al20 Osteopathic paper reporting on forces applied Reported that the SOT technique required Osteopathic craniosacral therapy is the for cranial therapy in student population force of b 1N same technique as sacro-occipital technique used by chiropractors. Graham et al21
A descriptive study of the forces applied Toggle performed on force plates to determine No forces for children available using toggle technique forces applied and if there was variability of forces between practitioners. Mean toggle force applied for adults of 111.2 N
Journal of Manipulative and Physiological Therapeutics Volume xx, Number
Todd et al Forces of Chiropractic Techniques on Children
Table 1. (continued) Study Snodgrass et al
Study Details 19
Zemelka23
Findings
Comment/s
Physiotherapist applying grade 1-1V Mobilization estimated to apply a force of These same physiotherapist mobilization mobilizations looking at intrapractitioner 22 N in adults methods are used by chiropractors. and interpractitioner repeatability Book chapter describing Thompson drop No specific forces available for adults or Description of technique to apply section technique children. Estimated to be same as similar forces to that of an adult HVLA in an adult of 112 N26 HVLA. Research is needed to assess the forces applied in children.
HAI, Harrison Hand-Held Adjusting Instrument; HVLA, high-velocity, low-amplitude; NMI, neuromuscular impulse adjusting instrument; SMT, spinal manipulative therapy; SOT, sacro-occcipital technique.
applied to children. 11,30 The sustained neuroapophyseal glides commonly used in physiotherapy practices are very similar to those used by chiropractors when treating children using spinal mobilization. Physical therapists (also called physiotherapists) apply spinal manipulation using level 1 mobilizations with forces estimated to be approximately 22 N for the adult population, although the literature does not specify a difference for children or infants. 19 Overall, spinal mobilization applies less force than HVLA spinal manipulation; however, its application in children needs further exploration because there is little research to draw upon.
Touch and Hold Technique
Fig 2. Force measurement experimental set-ups used by Colloca et al 22 (a, fixed instrument and force plate), Liebschner et al 24 (b, instrument applied to spinal analog material with force plate behind), and Koch and Girnus 27 (c, interphalangeal joint [IPJ] thrust to force plate placed on inner thigh). technique procedures are commonly taught at both undergraduate and postgraduate levels and can be used for all ages. It is very commonly used in young children and babies. Osteopathy uses an almost identical technique called craniosacral therapy, where the dura and fascia are worked upon with stretches and cranial therapy in children. 29 According to a recent osteopathic article, both chiropractic sacro-occipital and osteopathic craniosacral therapy techniques apply forces at below 1 N. 20
Spinal Mobilization Many of the techniques applied by doctors of chiropractic and other manual therapists treating infants and young children are similar and SMT is modified when
In this technique, a gentle pressure is applied to the fixated motion unit in the spinal column, and the practitioner waits to feel a gentle “giving way” of the tension in the tissues supporting the joint. Chiropractors reporting using the touch and hold technique have measured at approximately 2 N of pressure applied when using this technique in the pediatric population 31 (Table 3; Fig 3).
Toggle Toggle is a style of SMT that has been developed to address lateral motion dysfunction of the atlas. In adults and school-aged children, a patient is laid on a special table that has a drop-down section under the head piece. A patient is laid on his or her side, and using a contact over the atlas, the pisiform of the practitioner performs an HVLA thrust. The table drops away 12.7 mm to increase the speed of the thrust and to restore function to the atlas. 21 In an infant, the toggle adjustment is performed by laying the infant across the parent either in a side posture position or upright against a drop-piece section worn by the practitioner. The practitioner then uses a thumb or double-finger contact or cupped hand and delivers a very short and quick “flick” to encourage normality of movement in the lateral range of motion of the atlas. Toggle recoil and HVLA thrusts are applied at a speed that has been measured to induce physiological reflexive changes in the body. 42,43 After an extensive search of the
5
6
Todd et al Forces of Chiropractic Techniques on Children
Journal of Manipulative and Physiological Therapeutics Month 2016
Table 2. Comparison of Handheld Adjusting Instruments Mean Minimum Force Colloca et al Manufacturer a Activator I Activator II Activator III Activator IV Activator V HAI NMI (impulse)
47.1 47.1 NA 71.2 66.7 NA NA
Mean Maximum Force 22
Fixed Force Plate 61.5 137.8 128.2 123.1 d ND 44.9 123.5
Liebschner et al
24
Colloca et al22
Liebschner et al24
Stiff Tissue Analog b
Soft Tissue Analog
Manufacturer a
Fixed Force Plate
Stiff Tissue Analog
Soft Tissue Analog
ND 67 ND 71 62 ND 36
ND ~ 20 ND ~ 30 ~ 40 ND ~ 20
122.8 122.8 (200 c) NA 169.0 (200 c) 155.7 (220 c) NA 255 c
121.0 154.4 149.0 211.6 ND 275.0 380.2
ND 165 ND 108 189 ND 129
ND ~ 70 ND ~ 75 ~ 130 ND ~ 70
HAI, Harrison Hand-Held Adjusting Instrument; NA, not available; ND, not done; NMI, neuromuscular impulse adjusting instrument. a Values reported for Activators I, II, IV, and V taken from Activator Adjusting Instruments Brochure (Activator Methods International Ltd, Phoenix, AZ) and are converted to newtons from pounds. b The stiff tissue analog simulates the flexibility of an adult spine, whereas the soft tissue analog simulates the flexibility of a pediatric spine. c Values reported by Liebschner et al24 as having been provided by the manufacturer. d Colloca et al22 measured lower mean peak force on setting 2 for the Activator IV (121.0 N).
literature, no studies of the forces applied with toggle technique specifically in infants and children have been found. An adult study of the toggle technique demonstrated an average of 111.2 N of force. 21
Drop-Piece Table Also known as the Thompson technique, the drop-piece table technique is a full spine adjusting technique that emphasizes HVLA, and some low-force procedures, using drop-piece tables as an indispensable adjunct. 44 The drop-piece table has sections that move and drop away to enhance the speed of a spinal manipulation. It serves to enable relatively low-force adjustments to be delivered safely and effectively and permits fine-tuning of the forces applied by means of adjusting the tension on the drop pieces. 23 No specific data on force applied have been identified in this review of the literature, although it has been reported as being equivalent to adult manual HVLA. 23
DISCUSSION Excluding mechanically assisted techniques and modified SMT, many of the methods used by chiropractors are similar to those of other manual therapists, 45,46 including osteopaths using craniosacral therapy with a force of 1 N 20 and physical therapists using spinal manipulation/mobilization with a force of 22 N measured in adults. 19 In his recent article, Rome 45,46 notes that much of the concern about chiropractors using SMT on children is found in Englishlanguage medical practitioner journals, which seem to ignore the fact that their medical colleagues practicing manual medicine in Europe have been using SMT on children since the 1960s. Although it is known that medical manual therapists apply pediatric manual therapy with forces ranging from 50 N to 70 N, 27 specific force data on chiropractic
modified SMT in children have yet to be measured. The information on forces applied and reported adverse events, if any, should assist therapists in selecting the most appropriate technique. “The decision to apply a specific grade of mobilization or manipulation should be based on the patient age, weight, height, sex, neurologic development, muscular control, patient preference, and the clinical confidence and experience of the practitioner.” 11 In addition to these key factors, practitioners should also take into consideration the “safe limits” proposed by Marchand 15 to ensure that the forces associated with each technique are age appropriate. These safe limits suggest that low-force, low-speed therapies are more suitable for children younger than 2 years, increasing to moderate force with moderate speed in children aged 2 to 8 years, and then moderate force with high speed up to 18 years. Furthermore, Marchand recommends the newtons of force applied in the cervical spine be less than 20 N for infants and less than 85 N for 3- to 8-year-olds. The results of this literature review demonstrate that these limits are achievable with the appropriate application of several of the modern mechanical instruments and with touch and hold, mobilization, modified SMT, modified Toggle, or sacro-occipital technique. The values in Marchand's safe limits are based in part on the 2002 article by Koch et al 18 that reported that short-lasting apnea and bradycardia were associated with the use of around 50 N to 70 N of medically applied spinal manipulation in the cervical spine of a sample of 1-year-old infants. Those younger than 3 months were twice as likely to have severe bradycardia than those between 4 and 12 months of age. 18,27 It has been argued that for these measurements to accurately reflect the force likely to be experienced by the patient, allowances should be made for the compliance or flexibility of human tissue. This was noted by Liebschner et al 24 in their study of handheld adjusting devices, where the measurements were made
Journal of Manipulative and Physiological Therapeutics Volume xx, Number
Todd et al Forces of Chiropractic Techniques on Children
Table 3. Overview of Common Chiropractic Pediatric Techniques With Details of Forces and Serious Adverse Events (Where Known)
Technique
Description
Force Applied (N)
Proportion of Chiropractors Using Technique
Activator instrument
Handheld spring-loaded device that delivers a measured thrust (adjustable) 4 s versions currently available 1 electrical/mechanical impulse (Activator V)
20-40 N24
63%13-69%32
One case. An infant suffered from posterior rib fractures (no underlying pathology)33; however, the type of Activator instrument is unknown, as is whether it was applied correctly. It has been suggested that this may have been caused by the therapist doing a non–Activator Methods procedure, firmly holding child around the chest and inverting child prior to application of Activator instrument.34
See Table 2 Mean minimum setting for soft tissue analog
Serious Adverse Pediatric Events (Underlying Pathology)
Sacro-occipital technique (or craniosacral technique)
Whole-body approach to normalize tension in the fascia, muscles, and joints through stretching and cranial therapy
b1 N20
40%32
No adverse events involving a chiropractor applying craniosacral therapy or sacro-occipital technique reported in the literature
Modified spinal manipulation
HVLA thrusts to spinal and extraspinal articulations
Infants (b3 mo): ~ 11 N 3 mo–2 y: ~ 22 N
59%13-87%32
Seven reported cases were all prior to the publication of Marchand15 safe limits. It was unknown if technique applications in all these cases were correct. 1. Loss of consciousness (no underlying pathology)35 2. Anterior dislocation of atlas and fracture of odontoid axis at C2 (underlying pathology unknown)36 3. Quadriplegia; regressed to paraplegia (18 mo postoperatively) (congenital torticollis; spinal cord astrocytoma)37 4. Progressive neuromuscular deficits in legs; paraplegia (osteogenesis imperfecta)38 5. Severe headache, vomiting, left facial weakness, diplopia, ataxia (preexisting symptoms of headaches and transient cranial nerve deficits after gymnastics session)39 6. Neck pain; progression to drowsiness and weakness; hospitalization (congenital torticollis)40 7. Loss of consciousness/fainting (none)35
2-8 y: ~ 55 N 8-18 y: ~ 90 N15
Estimated by practitioners as a percentage of “usual” adult thrust measured in previous studies to be 112 N26
Touch and hold
Application of gentle pressure held at a single point until practitioner feels release of tension in tissues
2.2-7.7 N31
Unknown
No adverse events reported in the literature
Toggle
Use of thumb to deliver a short and quick thrust over the atlas
Average of 111.2 N in an adult21
25%41
No adverse events reported in the literature
Drop-piece table
High-velocity, relatively low-force adjustments with fine-tuning of the forces applied by means of adjusting the tension on the drop pieces
Unknown, but estimated to be similar to manual SMT of 112 N23,26 when used on an adult. Forces would be modified lower when used on a child or infant.
59%13
No adverse events reported in the literature
HVLA, high-velocity, low-amplitude; SMT, spinal manipulative therapy.
7
Todd et al Forces of Chiropractic Techniques on Children
Journal of Manipulative and Physiological Therapeutics Month 2016
160
140
120
Force (Newtons)
8
100
80
60
Key:
40
Safe Limits* Activator V
20
Activator IV NMI & Activator II SMT
0
Touch & Hold <3 months
3-23 months
2-8 years
9-18 years
Patient Age Ranges
>18 years
SOT
Fig 3. Forces applied using common chiropractic pediatric techniques and instruments applied directly to the spine. SMT, spinal manipulative therapy; SOT, sacro-occcipital technique; NMI, neuromuscular impulse adjusting instrument. *Safe limits recommended by Marchand. 15 Mean minimum force output for handheld instruments (NMI and Activators II, IV, V) are as reported by Liebschner et al 24 (using the spinal analog methodology).
using a soft tissue analog to better reflect a thrust into a spine on either an adult or a child (Fig 2). The diversity of measurement approaches for mechanical instruments has led to confusion in the literature regarding the levels of force associated with different devices and settings, with initial levels of thrust of the NMI and Activators III and IV reported by Colloca et al 22 as being very high (N 112 N) when on the lowest setting. However, the most recent research by Liebschner et al 24 indicates that the forces of Activator II, IV, and V are considerably lower when the measurements are conducted in a way that is analogous to the real-world application to the human spine. Liebschner et al 24 indicate that individual patient characteristics may change the level of force received, with an infant/child with a hyperflexible spine receiving a lower peak thrust force than a more hypoflexible adult spine at the same power setting, and handheld instruments further reduced the peak thrust force as it increased tissue compliance. It is unknown how this affects the forces from these instruments. The depth of subcutaneous tissue is also larger in an adult and less in a child, and measurements for a flexible spine with a thinner polymorphous overlay may produce more accurate forces for children using an Activator instrument. The specificity of any of the instruments measured is also unknown because the applicator tip on most of them is larger than most cervical vertebrae in an infant. 16,22 Considering all of this information, the application of the NMI, HAI, and each of
the Activator II, IV, and V instruments to the cervical region of children younger than 3 months delivers a force less than the 50 N to 70 N 18 where medical spinal manipulation on children was recorded by Koch. In addition, the forces applied at the lowest settings of the Activator II and NMI were both at the 20 N range recommended by Marchand as a maximal safe limit for infants younger than 3 months 15; however, the Activator IV and V minimum settings transmit forces above the 20 N level recommended by Marchand for children below 3 months of age when applied directly to the cervical spine.
LIMITATIONS This review did not include force data from other professions that share similar technique applications as chiropractic, and no data on joint displacement or laxity in children were collected or examined. All of the papers in this study where published in English, with the exception of one paper published in German that was translated into English. There is a need for research to be done on the forces applied with some mechanically assisted devices when used according to recommended protocols (such as through the thumb for a newborn child); therefore, some techniques were not included in this review because the research is not available. Finally, although adverse events from chiropractic and other manual therapies are rare, 6 this
Journal of Manipulative and Physiological Therapeutics Volume xx, Number
literature review found that the forces applied with manual modified SMT by chiropractors for children of any age have been estimated, not directly measured, and thus require further evaluation. Although there is a growing body of research on the forces associated with different techniques, there are numerous gaps relating to particular techniques. This information should be considered when applying this information in a clinical setting. 47
CONCLUSION This review found that technique selection and application by chiropractors treating infants and young children are typically modified in force and speed to suit the age and development of the child.
FUNDING SOURCES AND POTENTIAL CONFLICTS OF INTEREST No funding sources or conflicts of interest were reported for this study.
CONTRIBUTORSHIP INFORMATION Concept development (provided idea for the research): A.T. Design (planned the methods to generate the results): A.T., E.M., M.C. Supervision (provided oversight, responsible for organization and implementation, writing of the manuscript): E.M., M.C. Data collection/processing (responsible for experiments, patient management, organization, or reporting data): A.T. Analysis/interpretation (responsible for statistical analysis, evaluation, and presentation of the results): A.T., E.M., M.C. Literature search (performed the literature search): A.T. Writing (responsible for writing a substantive part of the manuscript): A.T. Critical review (revised manuscript for intellectual content, this does not relate to spelling and grammar checking): A.T., E.M., M.C.
ACKNOWLEDGMENTS The authors thank Naomi Knoblauch for assistance with formatting, grammatical editing, and sourcing references, and Dr Jens Duehr (chiropractor/researcher) for translation of a key research paper from German into English.
Todd et al Forces of Chiropractic Techniques on Children
REFERENCES 1. Lee AC, Li DH, Kemper KJ. Chiropractic care for children. Arch Pediatr Adolesc Med. 2000;154(4):401-407. 2. Xue CL, Zhang AL, Lin V, Myers R, Polus B, Story D. Acupuncture, chiropractic and osteopathy use in Australia: A national population survey. BMC Public Health. 2008;8:105. 3. French S, Charity M, Forsdike K, et al. Chiropractic Observation and Analysis Study (COAST): providing an understanding of current chiropractic practice. Med J Aust. 2013;199(10):687-691. 4. Vohra S, Johnston BC, Cramer K, Humphreys K. Adverse events associated with pediatric spinal manipulation: a systematic review. Pediatrics. 2007;119(1):e275-e283. 5. Doyle MF. Is chiropractic paediatric care safe? A best evidence topic. Clin Chiropr. 2011;14(3):97-105. 6. Todd AJ, Carroll MT, Robinson A, Mitchell EKL. Adverse events from chiropractic and other manual therapies for infants and children: A Review of the Literature. J Manipulative Physiol Ther. 2015;38(9):699-712. 7. Hayworth N, Ebrall P. Undergraduate Paediatric Curriculum at RMIT School of Chiropractic 2010. Melbourne: RMIT University; 2010. 8. Johnson C. Evidence-based practice in 5 simple steps. J Manipulative Physiol Ther. 2008;31(3):169-170. 9. Garbutt J, Brownstein DR, Klein EJ, et al. Reporting and disclosing medical errors: pediatricians' attitudes and behaviors. Arch Pediatr Adolesc Med. 2007;161(2):179-185. 10. Loren DJ, Klein EJ, Garbutt J, et al. Medical error disclosure among pediatricians: choosing carefully what we might say to parents. Arch Pediatr Adolesc Med. 2008;162(10):922-927. 11. Hawk C, Schneider M, Ferrance RJ, Hewitt E, Van Loon M, Tanis L. Best practices recommendations for chiropractic care for infants, children, and adolescents: results of a consensus process. J Manipulative Physiol Ther. 2009;32(8):639-647. 12. Gleberzon BJ. Chiropractic name techniques in Canada: a continued look at demographic trends and their impact on issues of jurisprudence. J Can Chiropr Assoc. 2002;46(4): 241-256. 13. Pohlman KA, Hondras MA, Long CR, Haan AG. Practice patterns of doctors of chiropractic with a pediatric diplomate: a crosssectional survey. BMC Complement Altern Med. 2010;10:26. 14. Haavik-Taylor H, Holt K, Murphy B. Exploring the neuromodulatory effects of the vertebral subluxation and chiropractic care. Med J Aust. 2010;40(1):37-44. 15. Marchand AM. A proposed model with possible implications for safety and technique adaptations for chiropractic spinal manipulative therapy for infants and children. J Manipulative Physiol Ther. 2015;38(9):9713-9726. 16. Fuhr AW, Menke JM. Status of activator methods chiropractic technique, theory and practice. J Manipulative Physiol Ther. 2005;28(2):135.e1-135.e20. 17. Koch LE, Biedermann H, Saternus KS. High cervical stress and apnoea. Forensic Sci Int. 1998;97(1):1-9. 18. Koch LE, Koch H, Graumann-Brunt S, Stolle D, Ramirez JM, Saternus KS. Heart rate changes in response to mild mechanical irritation of the high cervical spinal cord region in infants. Forensic Sci Int. 2002;128(3):168-176. 19. Snodgrass SJ, Rivett DA, Robertson VJ. Manual forces applied during cervical mobilization. J Manipulative Physiol Ther. 2007;30(1):17-25. 20. Zegarra-Parodi R, De Chauvigny de Blot P, Rickards L, Renard E-O. Cranial palpation pressures used by osteopathy students: effects of standardized protocol training. J Am Osteopath Assoc. 2009;109(2):79-85.
9
10
Todd et al Forces of Chiropractic Techniques on Children
21. Graham BA, Clausen P, Bolton PS. A descriptive study of the force and displacement profiles of the toggle-recoil spinal manipulative procedure (adjustment) as performed by chiropractors. Man Ther. 2010;15(1):74-79. 22. Colloca CJ, Keller TS, Black P, Normand MC, Harrison DE, Harrison DD. Comparison of mechanical force of manually assisted chiropractic adjusting instruments. J Manipulative Physiol Ther. 2005;28(6):414-422. 23. Zemelka W, ed. The Thompson Technique. Bettendorf, IA: Victoria Press; 1992. 24. Liebschner MA, Chun K, Kim N, Ehni B. In vitro biomechanical evaluation of single impulse and repetitive mechanical shockwave devices utilized for spinal manipulative therapy. Ann Biomed Eng. 2014;42(12):2524-2536. 25. Marchand AM. Chiropractic care of children from birth to adolescence and classification of reported conditions: an Internet cross-sectional survey of 956 European chiropractors. J Manipulative Physiol Ther. 2012;35(5):372-380. 26. Herzog W. The biomechanics of spinal manipulation. J Bodyw Mov Ther. 2010;14(3):280-286. 27. Koch LE, Girnus U. Kraftmessung bei anwendung der impulstechink in der chirotherapie. Man Med. 1998;36(1):21-26. 28. Blum C. The compendium of SOT peer reviewed published literature from 1984-2000. J Vert Sublux Res. 2002;4:123. 29. Hayes NM, Bezilla TA. Incidence of iatrogenesis associated with osteopathic manipulative treatment of pediatric patients. J Am Osteopath Assoc. 2006;106(10):605-608. 30. Biedermann H. Manual therapy in children: proposals for an etiologic model. J Manipulative Physiol Ther. 2005;28(3):e1-e15. 31. Miller JE, Newell D, Bolton JE. Efficacy of chiropractic manual therapy on infant colic: a pragmatic single-blind, randomized controlled trial. J Manipulative Physiol Ther. 2012;35(8):600-607. 32. Alcantara J, Ohm J, Kunz D. The chiropractic care of children. J Altern Complement Med. 2010;16(6):621-626. 33. Wilson P, Greiner M, Duma E. Posterior rib fractures in a young infant who received chiropractic care. Pediatrics. 2012;130(5):1359-1362. 34. Fischer RS, Fuhr AW. Rebuttal of potential forces of instrument adjusting on an infant rib fracture. Pediatr eLett. 2013 [Viewed 13 August 2014. http://pediatrics.aappublications.org/content/ 130/5/e1359.comments#rebuttal-of-potential-forces-ofinstrument-adjusting-on-an-infant-rib-fracture].
Journal of Manipulative and Physiological Therapeutics Month 2016
35. Klougart N, Leboeuf-Yde C, Rasmussen LR. Safety in chiropractic practice. Part II: treatment to the upper neck and the rate of cerebrovascular incidents. J Manipulative Physiol Ther. 1996;19(9):563-569. 36. Rageot E. Complications and accidents in vertebral manipulation. Cah Coll Med Hop Paris. 1968;9(14):1149-1154. 37. Shafrir Y, Kaufman BA. Quadriplegia after chiropractic manipulation in an infant with congenital torticollis caused by a spinal cord astrocytoma. J Pediatr. 1992;120(2 Pt 1): 266-269. 38. Ziv I, Rang M, Hoffman HJ. Paraplegia in osteogenesis imperfecta. A case report. J Bone Joint Surg (Br). 1983; 65(2):184-185. 39. Zimmerman AW, Kumar AJ, Gadoth N, Hodges FJ. Traumatic vertebrobasilar occlusive disease in childhood. Neurology. 1978;28(2):185-188. 40. L'Ecuyer JL. Congenital occipitalization of the atlas with chiropractic manipulations: a case report. Nebr State Med J. 1959;44:546-550. 41. Christensen MG, Kollasch MW, Ward R, Webb K, Day A, ZumBrunnen JJ. Job Analysis of Chiropractic. Greeley, CO: National Board of Chiropractic Examiners; 2005. 42. Triano JJ, Descarreaux M, Dugas C. Review of approaches for performance training in spinal manipulation. J Electromyogr Kinesiol. 2012;22(5):5732-5739. 43. Descarreaux M, Dugas C. Learning spinal manipulation skills: assessment of biomechanical parameters in a 5-year longitudinal study. J Manipulative Physiol Ther. 2010;33(3): 226-230. 44. Cooperstein R. Technique system overview: Thompson technique. Chiropr Tech. 1995;7:60-63. 45. Rome PL. Medical management of pediatric and nonmusculoskeletal conditions by spinal manipulation. Med J Aust. 2013;43(4):131-136. 46. Johnson C, Rubinstein SM, Cote P, et al. Chiropractic care and public health: answering difficult questions about safety, care through the lifespan, and community action. J Manipulative Physiol Ther. 2012;35(7):493-513. 47. Hawk C, Schneider MJ, Vallone S, Hewitt EG. Best practices for chiropractic care of children: a consensus update. J Manipulative Physiol Ther. 2016;39(3):158-168, http://dx. doi.org/10.1016/j.jmpt.2016.02.015.
Matthew T. Carroll, PhD, b and Eleanor K.L. Mitchell, PhD c, d ABSTRACT Objective: The purpose of this study is to review the available literature that describes forces of the most commonly used chiropractic techniques for children. Methods: Review of the English-language literature using search terms Chiropract* and technique, protocol, or approach in databases PubMed, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine, and Index to Chiropractic Literature and direct contact with authors of articles and book chapters. Results: Eleven articles that discussed the 7 most commonly used pediatric chiropractic techniques and the forces applied were identified. Chiropractic techniques reviewed described forces that were modified based on the age of the patient. Force data for mechanically assisted devices were varied, with the minimum force settings for some devices outside the age-specific safe range recommended in the literature when not modified in some way. Conclusion: This review found that technique selection and application by chiropractors treating infants and young children are typically modified in force and speed to suit the age and development of the child. (J Manipulative Physiol Ther 2016;xx:1-10) Key Indexing Terms: Chiropractic Manipulation; Children; Review of Literature
INTRODUCTION More than 30 million child visits to doctors of chiropractic occur in the United States every year. 1 It is estimated that more than 19.1 million chiropractic visits occur in Australia annually 2 and other studies estimate that 8.6% of all visits are from children. 3 By combining these two studies findings, we can estimate that in excess of 1.6 million child visits occur in Australia every year. Given this estimate, the published cases of serious adverse events in infants and children receiving chiropractic or other types of manual therapy are exceedingly rare, 4–6 and there have been no cases of death associated with chiropractic care of a
Private Practice, Sale, Australia. School of Rural Health–Churchill, Monash University, Churchill, Australia. c Department of Rural and Indigenous Health, School of Rural Health, Monash University, Moe, Australia. d School of Rural Health–East Gippsland, Monash University, Bairnsdale, Australia. Submit requests for reprints to: Angela J. Todd, BAppSc(Chiro), Grad Dip(Chiro Pediatrics), Private Practice, PO Box 1500, Sale, VIC 3850, Australia. (e-mail: [email protected]). Paper submitted November 17, 2014; in revised form June 11, 2015; accepted June 15, 2015. 0161-4754 © 2016 by National University of Health Sciences. http://dx.doi.org/10.1016/j.jmpt.2016.05.006 b
children reported in the academic literature to date. 4–6 Nonetheless, studies of the amount of force used on children for safety purposes should still be considered. In Australia and the United States, chiropractic students undertake extensive theoretical and practical training at the university level, including study of and experience with the pediatric population. 7 Chiropractors are trained to perform a thorough history and examination to determine whether chiropractic care is appropriate and identify a suitable technique, given the age and neurologic presentation of the child. Chiropractors have a range of techniques available to them and can modify these to suit the age and condition of the patient. The process of selecting one type of chiropractic technique over another is based on many factors, including the techniques the practitioner is clinically experienced in applying and the perceived effectiveness of each, as well as the practitioner's understanding of the biological plausibility of using a particular therapy and the associated research evidence base. 8 It should be noted that health professionals of all types face the same considerations when determining appropriate treatment approaches. 9–11 Data from the National Board of Chiropractic Examiners identified that three-quarters of chiropractors use traditional styles of chiropractic spinal manipulation (diversified or Gonstead technique) and more than half use an Activator instrument or the sacro-occcipital technique (SOT). 12 Although these data are not age specific, a 2010 cross-sectional
2
Todd et al Forces of Chiropractic Techniques on Children
survey of 135 chiropractors with pediatric diplomate qualifications in the United States 13 revealed that reduced-force diversified technique (spinal manipulative technique that has been modified to be lower force and amplitude) was used by 59% of pediatric chiropractors; 63% reported using an Activator instrument, 59% a drop-section table, and 77% cranial therapy. In addition, this study found that cranial and Activator techniques were used mainly for children 5 years and younger, and that modified diversified, Activator, and drop-section table adjustments were used on older children. The Activator instrument, SOT, toggle, touch and hold, and modified spinal manipulative therapy (SMT) were typically used by chiropractors for restoring joint and neurologic function, 14 and particularly in children to reduce neck pain, back pain, and joint stiffness. 13 Given the diversity of styles of chiropractic manipulation, there are currently no peer-reviewed articles that review the amount of force used in commonly used pediatric manipulation techniques. Therefore, the purpose of this study is to review the available literature that describes forces of the most commonly used chiropractic techniques for children.
METHODS The academic literature was initially searched in PubMed, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine, and Index to Chiropractic Literature with a broad strategy, using the term chiropract* combined with the terms (technique OR protocol OR approach) in a “full-text” or “all-fields” search. All records published in English were screened for information about the force used in the application of any manual therapy technique. After initial removal of duplicates, practice guidelines, and non–peer-reviewed items (eg, commentaries and letters), there were further exclusions, including case reports and articles where neither the title nor abstract indicated specific discussion of technique application. A second round of technique-specific searches was also conducted. The terms (force OR thrust) were combined in individual full-text or all-fields searches with each of “spinal manipulation,” “adjusting instrument,” (“sacro-occipital technique,” OR “craniosacral therapy”), “toggle,” “touch and hold,” and (“Thompson technique” OR “drop piece”). Records were screened as for the initial search (Fig 1). A manual review of the reference lists of included articles was undertaken along with contact with authors to identify articles that were more recent.
RESULTS The initial search captured 1796 potential articles, of which 54 full-text articles were reviewed. This search
Journal of Manipulative and Physiological Therapeutics Month 2016
identified 2 articles by Marchand, 15,16 which when references were hand searched yielded 3 more articles, by Koch et al 17,18 and Snodgrass et al. 19 Searching of the literature using technique-specific search terms resulted in the inclusion of a further 4 studies 16,20–22 and 1 textbook source, 23 with an additional in-press journal article yielding direct contact with the author 24 (Table 1).
Spinal Manipulative Therapy Spinal manipulation has been defined as the application of a precisely controlled high-velocity, low-amplitude (HVLA) thrust to a joint, causing tissue deformation of the spine and surrounding tissue. The thrust is designed to restore motion in the targeted joint by applying force to the area of segmental restricted motion. 15,26 Chiropractors in Europe were surveyed about their practice techniques for children, 25 resulting in the following guidelines for pediatric chiropractic, identifying 4 grades of therapeutic input for the application of pediatric SMT for different age groups 15: Grade 1: neonates and infants aged 0 to 2 months (low force, low speed) at 10% of estimated force for adults (equivalent to 11.2 N) Grade 2: infants and toddlers aged 3 to 23 months (low force, low speed) at 30% of estimated force for adults (equivalent to 33.6 N) Grade 3: young children aged 2 years to 8 years or younger (moderate force, moderate speed) at 50% of estimated adult force (equivalent to 56 N) Grade 4: older children and young adults aged 8 to 18 years (moderate force, high speed) at 80% of estimated adult force (equivalent to 89.6 N) A similar set of guidelines for different age groups has been developed by Marchand, 15 drawing on findings from an extensive study of tensile strength and osteoligamentous failure rates in pediatric spines as well as a report of transient bradycardia and apnea events that occurred with thrusts of 50 N to 70 N in infants younger than 3 months. 18 Marchand 15 has recommended that SMT be applied at a maximum cervical loading of 20 N for neonates, 50 N for children aged 2 to 23 months, 85 N for children aged 2 to 8 years, 135 N for 8- to 18-year-olds, and 155 N for adults to prevent possible adverse physiological reactions caused by any inappropriate level of force. The report of transient events occurring in infants as a result of thrusts in the 50 N to 70 N range comes from research measured by Koch and Girnus. 27 The measurements involved resting the force plate on the inside of the investigator's thigh (Fig 2c) in an attempt to simulate a manipulation on an infant, with the thrusts repeated 50 times. The range of forces was between 50 N and 70 N, with 1 outlier thrust of 30 N. No infants were involved in the measurement of these thrusts. The
Journal of Manipulative and Physiological Therapeutics Volume xx, Number
Todd et al Forces of Chiropractic Techniques on Children
Records identified through broad database search (n = 1796)
Records screened after duplicates, practice guidelines and non-peer reviewed items removed (n = 1045)
Full-text articles assessed for eligibility (n = 54)
Records Excluded after screening (n = 751)
Records Excluded (n = 991)
Full text articles excluded (no discussion of force) (n = 48)
Specific technique searches (n = 6)
Fig 1. Search results. investigators were both practitioners who used manipulation to the cervical spine of infants.
Activator Instrument The Activator instrument is a small handheld device designed by Arlan Fuhr in the early 1980s that delivers a measured thrust, with the force applied able to be modified by altering the instrument settings. 16 There are now 5 versions of the Activator instrument available, each with a different range of possible forces (Table 2). There have been 2 articles attempting to measure the forces applied by these and other instruments, with different measurement approaches resulting in different force readings (Fig 2). According to Colloca et al, 22 the mean minimum force applied by an Activator I is 61.5 N (Table 2), whereas the Activators II and III apply approximately 137.8 N and 128.2 N, respectively, and the Activator IV applies 123.1 N. 22 These values were measured by fixing the instruments to a stable surface and applying the tip directly to a metal force plate (Fig 2a). However, Liebschner et al 24 argue that the approach to applying and measuring force needs to be analogous to the way in which it is delivered to a human patient and so incorporated a range of polymorphous structures to replicate different levels of tissue stiffness in the human spine (Fig 2b). This use of a spinal analog resulted in notably lower-force recordings (Table 2).
The Activator V has recently become available and is a mechanically assisted handheld instrument that is battery powered (as opposed to the previous spring-loaded Activator versions). The minimum force applied with this instrument was measured with a soft polymorphous substance analogous to a flexible child spine at approximately 40 N. 24
Electrically Assisted Mechanical Adjusting Instruments Other instruments that deliver a mechanical force have also been developed. The Harrison Adjusting Instrument (HAI) and the Neuromuscular Impulse (NMI) both offer electrically assisted mechanical handheld measured thrusts. The HAI is reported to give a minimum thrust of about 45 N into a fixed force plate on a hard surface 22 (Table 2) and the NMI a minimum of 20 N onto a soft tissue analog 24 (Fig 2; Table 2). As stated earlier, the Activator V is also mechanically loaded and is battery powered with a minimal force setting into a soft tissue analog of 40 N.
Sacro-occipital Technique Sacro-occcipital technique is a whole-body approach to restoring neurologic function by normalizing tension in the fascia, muscles, spine, pelvis, and cranial joints and reducing tension along the dura. 28 Sacro-occcipital
3
4
Todd et al Forces of Chiropractic Techniques on Children
Journal of Manipulative and Physiological Therapeutics Month 2016
Table 1. Summary of Evidence: Forces Applied to Perform Pediatric Chiropractic Techniques Study Marchand
Study Details 25
Findings
Comment/s
Cross-sectional survey of 956 European 96.3% of surveyed chiropractors treated Estimation of forces applied in modified SMT based on survey data and not from chiropractors relating to technique usage, children with no severe adverse events. adverse events in various ages of children Most child patients were younger than 2 y or actual measurements on force plates older than 12 y. Forces same as adults for children 13-18 y (62.7% of respondents), speed was also same as adult (45% of respondents), cavitation same as an adult (42% of respondents). No specific of force or speed data for children younger than 2 y, in comparison to adult
Fuhr and Menke16
Narrative review of all Activator instrument The force and impulse energy of the literature N35 y up to and including 2003 Activator instrument allows this technique to produce the same results for patients as seen with manual spinal adjustment.
This article was missing more recent data provided by Liebschner et al24 on force profiles of the full range of Activator instruments.
Marchand15
A literature review of tensile strength of Proposed the following guidelines for the adult and pediatric spines maximum safe level of forces into the cervical spine from SMT for different age groups: • 20N, neonates • 50N, 3-23 mo • 85N, 3-8 y • 135N, 8-18 y
Tensile strength differences between pediatric and adult spines led to a model of care for safe application of pediatric SMT.
Koch et al18
Prospective clinical trial of 199 infants to investigate vegetative reactions after mechanical irritation of suboccipital region
Infants received upper cervical manual therapy from a medical manipulator. Thrusts reported to be in the 50-70 N range with apnea and flushing of skin observed in 50 infants
The estimation of applied force reported in this study was based on previous work by the authors (see next entry).
Koch and Girnus27
Repeated measurements of force applied with fingertip thrust (to approximate spinal manipulation of an infant) by 2 experienced chiropractors
Measure of 25 thrusts each into a force plate by 2 medical practitioners, simulating a medical manipulation on a child. Mean force applied for medical manipulation on a child of 50-70 N
Medical manipulation simulation on a force plate was higher than that estimated for modified manipulation by a chiropractor.25
Colloca et al22
Measurement of peak forces at each setting on the Activator instruments I, II, III, and IV. The HAI and NMI instruments were applied directly to a force plate.
The electrically assisted HAI and NMI produced the largest ranges between the highest and lowest settings and highest maximum peak force when compared with the spring-loaded Activator instruments. Forces recorded on stiff force plate on minimum settings ranged from 61 N to 137.8 N across Activator instruments and 44.9 N for HAI and 123.5 N for NMI.
The experimental set-up did not allow for measurements to approximate the actual force experienced at the joint, which is protected by tissue and some dampening by being held by the practitioner.
Liebschner et al24
Measurement of peak forces at the minimum and maximum setting on the Activator instruments II, IV, and V and the NMI. Instruments were applied to polymorphous substances (analogous to the spine and surrounding tissue) attached to a force plate. Instruments were tested in a fixed position and handheld.
The softer polymorphous substance reduced Activator instrument had lower minimal the force measured for each instrument, as forces than previously reported by did testing the instruments in a handheld Colloca et al.22 set-up. Forces for the variety of Activator instruments used at lowest setting ranged from 20 N to 40 N on soft tissue analog.
Zegarra-Parodi et al20 Osteopathic paper reporting on forces applied Reported that the SOT technique required Osteopathic craniosacral therapy is the for cranial therapy in student population force of b 1N same technique as sacro-occipital technique used by chiropractors. Graham et al21
A descriptive study of the forces applied Toggle performed on force plates to determine No forces for children available using toggle technique forces applied and if there was variability of forces between practitioners. Mean toggle force applied for adults of 111.2 N
Journal of Manipulative and Physiological Therapeutics Volume xx, Number
Todd et al Forces of Chiropractic Techniques on Children
Table 1. (continued) Study Snodgrass et al
Study Details 19
Zemelka23
Findings
Comment/s
Physiotherapist applying grade 1-1V Mobilization estimated to apply a force of These same physiotherapist mobilization mobilizations looking at intrapractitioner 22 N in adults methods are used by chiropractors. and interpractitioner repeatability Book chapter describing Thompson drop No specific forces available for adults or Description of technique to apply section technique children. Estimated to be same as similar forces to that of an adult HVLA in an adult of 112 N26 HVLA. Research is needed to assess the forces applied in children.
HAI, Harrison Hand-Held Adjusting Instrument; HVLA, high-velocity, low-amplitude; NMI, neuromuscular impulse adjusting instrument; SMT, spinal manipulative therapy; SOT, sacro-occcipital technique.
applied to children. 11,30 The sustained neuroapophyseal glides commonly used in physiotherapy practices are very similar to those used by chiropractors when treating children using spinal mobilization. Physical therapists (also called physiotherapists) apply spinal manipulation using level 1 mobilizations with forces estimated to be approximately 22 N for the adult population, although the literature does not specify a difference for children or infants. 19 Overall, spinal mobilization applies less force than HVLA spinal manipulation; however, its application in children needs further exploration because there is little research to draw upon.
Touch and Hold Technique
Fig 2. Force measurement experimental set-ups used by Colloca et al 22 (a, fixed instrument and force plate), Liebschner et al 24 (b, instrument applied to spinal analog material with force plate behind), and Koch and Girnus 27 (c, interphalangeal joint [IPJ] thrust to force plate placed on inner thigh). technique procedures are commonly taught at both undergraduate and postgraduate levels and can be used for all ages. It is very commonly used in young children and babies. Osteopathy uses an almost identical technique called craniosacral therapy, where the dura and fascia are worked upon with stretches and cranial therapy in children. 29 According to a recent osteopathic article, both chiropractic sacro-occipital and osteopathic craniosacral therapy techniques apply forces at below 1 N. 20
Spinal Mobilization Many of the techniques applied by doctors of chiropractic and other manual therapists treating infants and young children are similar and SMT is modified when
In this technique, a gentle pressure is applied to the fixated motion unit in the spinal column, and the practitioner waits to feel a gentle “giving way” of the tension in the tissues supporting the joint. Chiropractors reporting using the touch and hold technique have measured at approximately 2 N of pressure applied when using this technique in the pediatric population 31 (Table 3; Fig 3).
Toggle Toggle is a style of SMT that has been developed to address lateral motion dysfunction of the atlas. In adults and school-aged children, a patient is laid on a special table that has a drop-down section under the head piece. A patient is laid on his or her side, and using a contact over the atlas, the pisiform of the practitioner performs an HVLA thrust. The table drops away 12.7 mm to increase the speed of the thrust and to restore function to the atlas. 21 In an infant, the toggle adjustment is performed by laying the infant across the parent either in a side posture position or upright against a drop-piece section worn by the practitioner. The practitioner then uses a thumb or double-finger contact or cupped hand and delivers a very short and quick “flick” to encourage normality of movement in the lateral range of motion of the atlas. Toggle recoil and HVLA thrusts are applied at a speed that has been measured to induce physiological reflexive changes in the body. 42,43 After an extensive search of the
5
6
Todd et al Forces of Chiropractic Techniques on Children
Journal of Manipulative and Physiological Therapeutics Month 2016
Table 2. Comparison of Handheld Adjusting Instruments Mean Minimum Force Colloca et al Manufacturer a Activator I Activator II Activator III Activator IV Activator V HAI NMI (impulse)
47.1 47.1 NA 71.2 66.7 NA NA
Mean Maximum Force 22
Fixed Force Plate 61.5 137.8 128.2 123.1 d ND 44.9 123.5
Liebschner et al
24
Colloca et al22
Liebschner et al24
Stiff Tissue Analog b
Soft Tissue Analog
Manufacturer a
Fixed Force Plate
Stiff Tissue Analog
Soft Tissue Analog
ND 67 ND 71 62 ND 36
ND ~ 20 ND ~ 30 ~ 40 ND ~ 20
122.8 122.8 (200 c) NA 169.0 (200 c) 155.7 (220 c) NA 255 c
121.0 154.4 149.0 211.6 ND 275.0 380.2
ND 165 ND 108 189 ND 129
ND ~ 70 ND ~ 75 ~ 130 ND ~ 70
HAI, Harrison Hand-Held Adjusting Instrument; NA, not available; ND, not done; NMI, neuromuscular impulse adjusting instrument. a Values reported for Activators I, II, IV, and V taken from Activator Adjusting Instruments Brochure (Activator Methods International Ltd, Phoenix, AZ) and are converted to newtons from pounds. b The stiff tissue analog simulates the flexibility of an adult spine, whereas the soft tissue analog simulates the flexibility of a pediatric spine. c Values reported by Liebschner et al24 as having been provided by the manufacturer. d Colloca et al22 measured lower mean peak force on setting 2 for the Activator IV (121.0 N).
literature, no studies of the forces applied with toggle technique specifically in infants and children have been found. An adult study of the toggle technique demonstrated an average of 111.2 N of force. 21
Drop-Piece Table Also known as the Thompson technique, the drop-piece table technique is a full spine adjusting technique that emphasizes HVLA, and some low-force procedures, using drop-piece tables as an indispensable adjunct. 44 The drop-piece table has sections that move and drop away to enhance the speed of a spinal manipulation. It serves to enable relatively low-force adjustments to be delivered safely and effectively and permits fine-tuning of the forces applied by means of adjusting the tension on the drop pieces. 23 No specific data on force applied have been identified in this review of the literature, although it has been reported as being equivalent to adult manual HVLA. 23
DISCUSSION Excluding mechanically assisted techniques and modified SMT, many of the methods used by chiropractors are similar to those of other manual therapists, 45,46 including osteopaths using craniosacral therapy with a force of 1 N 20 and physical therapists using spinal manipulation/mobilization with a force of 22 N measured in adults. 19 In his recent article, Rome 45,46 notes that much of the concern about chiropractors using SMT on children is found in Englishlanguage medical practitioner journals, which seem to ignore the fact that their medical colleagues practicing manual medicine in Europe have been using SMT on children since the 1960s. Although it is known that medical manual therapists apply pediatric manual therapy with forces ranging from 50 N to 70 N, 27 specific force data on chiropractic
modified SMT in children have yet to be measured. The information on forces applied and reported adverse events, if any, should assist therapists in selecting the most appropriate technique. “The decision to apply a specific grade of mobilization or manipulation should be based on the patient age, weight, height, sex, neurologic development, muscular control, patient preference, and the clinical confidence and experience of the practitioner.” 11 In addition to these key factors, practitioners should also take into consideration the “safe limits” proposed by Marchand 15 to ensure that the forces associated with each technique are age appropriate. These safe limits suggest that low-force, low-speed therapies are more suitable for children younger than 2 years, increasing to moderate force with moderate speed in children aged 2 to 8 years, and then moderate force with high speed up to 18 years. Furthermore, Marchand recommends the newtons of force applied in the cervical spine be less than 20 N for infants and less than 85 N for 3- to 8-year-olds. The results of this literature review demonstrate that these limits are achievable with the appropriate application of several of the modern mechanical instruments and with touch and hold, mobilization, modified SMT, modified Toggle, or sacro-occipital technique. The values in Marchand's safe limits are based in part on the 2002 article by Koch et al 18 that reported that short-lasting apnea and bradycardia were associated with the use of around 50 N to 70 N of medically applied spinal manipulation in the cervical spine of a sample of 1-year-old infants. Those younger than 3 months were twice as likely to have severe bradycardia than those between 4 and 12 months of age. 18,27 It has been argued that for these measurements to accurately reflect the force likely to be experienced by the patient, allowances should be made for the compliance or flexibility of human tissue. This was noted by Liebschner et al 24 in their study of handheld adjusting devices, where the measurements were made
Journal of Manipulative and Physiological Therapeutics Volume xx, Number
Todd et al Forces of Chiropractic Techniques on Children
Table 3. Overview of Common Chiropractic Pediatric Techniques With Details of Forces and Serious Adverse Events (Where Known)
Technique
Description
Force Applied (N)
Proportion of Chiropractors Using Technique
Activator instrument
Handheld spring-loaded device that delivers a measured thrust (adjustable) 4 s versions currently available 1 electrical/mechanical impulse (Activator V)
20-40 N24
63%13-69%32
One case. An infant suffered from posterior rib fractures (no underlying pathology)33; however, the type of Activator instrument is unknown, as is whether it was applied correctly. It has been suggested that this may have been caused by the therapist doing a non–Activator Methods procedure, firmly holding child around the chest and inverting child prior to application of Activator instrument.34
See Table 2 Mean minimum setting for soft tissue analog
Serious Adverse Pediatric Events (Underlying Pathology)
Sacro-occipital technique (or craniosacral technique)
Whole-body approach to normalize tension in the fascia, muscles, and joints through stretching and cranial therapy
b1 N20
40%32
No adverse events involving a chiropractor applying craniosacral therapy or sacro-occipital technique reported in the literature
Modified spinal manipulation
HVLA thrusts to spinal and extraspinal articulations
Infants (b3 mo): ~ 11 N 3 mo–2 y: ~ 22 N
59%13-87%32
Seven reported cases were all prior to the publication of Marchand15 safe limits. It was unknown if technique applications in all these cases were correct. 1. Loss of consciousness (no underlying pathology)35 2. Anterior dislocation of atlas and fracture of odontoid axis at C2 (underlying pathology unknown)36 3. Quadriplegia; regressed to paraplegia (18 mo postoperatively) (congenital torticollis; spinal cord astrocytoma)37 4. Progressive neuromuscular deficits in legs; paraplegia (osteogenesis imperfecta)38 5. Severe headache, vomiting, left facial weakness, diplopia, ataxia (preexisting symptoms of headaches and transient cranial nerve deficits after gymnastics session)39 6. Neck pain; progression to drowsiness and weakness; hospitalization (congenital torticollis)40 7. Loss of consciousness/fainting (none)35
2-8 y: ~ 55 N 8-18 y: ~ 90 N15
Estimated by practitioners as a percentage of “usual” adult thrust measured in previous studies to be 112 N26
Touch and hold
Application of gentle pressure held at a single point until practitioner feels release of tension in tissues
2.2-7.7 N31
Unknown
No adverse events reported in the literature
Toggle
Use of thumb to deliver a short and quick thrust over the atlas
Average of 111.2 N in an adult21
25%41
No adverse events reported in the literature
Drop-piece table
High-velocity, relatively low-force adjustments with fine-tuning of the forces applied by means of adjusting the tension on the drop pieces
Unknown, but estimated to be similar to manual SMT of 112 N23,26 when used on an adult. Forces would be modified lower when used on a child or infant.
59%13
No adverse events reported in the literature
HVLA, high-velocity, low-amplitude; SMT, spinal manipulative therapy.
7
Todd et al Forces of Chiropractic Techniques on Children
Journal of Manipulative and Physiological Therapeutics Month 2016
160
140
120
Force (Newtons)
8
100
80
60
Key:
40
Safe Limits* Activator V
20
Activator IV NMI & Activator II SMT
0
Touch & Hold <3 months
3-23 months
2-8 years
9-18 years
Patient Age Ranges
>18 years
SOT
Fig 3. Forces applied using common chiropractic pediatric techniques and instruments applied directly to the spine. SMT, spinal manipulative therapy; SOT, sacro-occcipital technique; NMI, neuromuscular impulse adjusting instrument. *Safe limits recommended by Marchand. 15 Mean minimum force output for handheld instruments (NMI and Activators II, IV, V) are as reported by Liebschner et al 24 (using the spinal analog methodology).
using a soft tissue analog to better reflect a thrust into a spine on either an adult or a child (Fig 2). The diversity of measurement approaches for mechanical instruments has led to confusion in the literature regarding the levels of force associated with different devices and settings, with initial levels of thrust of the NMI and Activators III and IV reported by Colloca et al 22 as being very high (N 112 N) when on the lowest setting. However, the most recent research by Liebschner et al 24 indicates that the forces of Activator II, IV, and V are considerably lower when the measurements are conducted in a way that is analogous to the real-world application to the human spine. Liebschner et al 24 indicate that individual patient characteristics may change the level of force received, with an infant/child with a hyperflexible spine receiving a lower peak thrust force than a more hypoflexible adult spine at the same power setting, and handheld instruments further reduced the peak thrust force as it increased tissue compliance. It is unknown how this affects the forces from these instruments. The depth of subcutaneous tissue is also larger in an adult and less in a child, and measurements for a flexible spine with a thinner polymorphous overlay may produce more accurate forces for children using an Activator instrument. The specificity of any of the instruments measured is also unknown because the applicator tip on most of them is larger than most cervical vertebrae in an infant. 16,22 Considering all of this information, the application of the NMI, HAI, and each of
the Activator II, IV, and V instruments to the cervical region of children younger than 3 months delivers a force less than the 50 N to 70 N 18 where medical spinal manipulation on children was recorded by Koch. In addition, the forces applied at the lowest settings of the Activator II and NMI were both at the 20 N range recommended by Marchand as a maximal safe limit for infants younger than 3 months 15; however, the Activator IV and V minimum settings transmit forces above the 20 N level recommended by Marchand for children below 3 months of age when applied directly to the cervical spine.
LIMITATIONS This review did not include force data from other professions that share similar technique applications as chiropractic, and no data on joint displacement or laxity in children were collected or examined. All of the papers in this study where published in English, with the exception of one paper published in German that was translated into English. There is a need for research to be done on the forces applied with some mechanically assisted devices when used according to recommended protocols (such as through the thumb for a newborn child); therefore, some techniques were not included in this review because the research is not available. Finally, although adverse events from chiropractic and other manual therapies are rare, 6 this
Journal of Manipulative and Physiological Therapeutics Volume xx, Number
literature review found that the forces applied with manual modified SMT by chiropractors for children of any age have been estimated, not directly measured, and thus require further evaluation. Although there is a growing body of research on the forces associated with different techniques, there are numerous gaps relating to particular techniques. This information should be considered when applying this information in a clinical setting. 47
CONCLUSION This review found that technique selection and application by chiropractors treating infants and young children are typically modified in force and speed to suit the age and development of the child.
FUNDING SOURCES AND POTENTIAL CONFLICTS OF INTEREST No funding sources or conflicts of interest were reported for this study.
CONTRIBUTORSHIP INFORMATION Concept development (provided idea for the research): A.T. Design (planned the methods to generate the results): A.T., E.M., M.C. Supervision (provided oversight, responsible for organization and implementation, writing of the manuscript): E.M., M.C. Data collection/processing (responsible for experiments, patient management, organization, or reporting data): A.T. Analysis/interpretation (responsible for statistical analysis, evaluation, and presentation of the results): A.T., E.M., M.C. Literature search (performed the literature search): A.T. Writing (responsible for writing a substantive part of the manuscript): A.T. Critical review (revised manuscript for intellectual content, this does not relate to spelling and grammar checking): A.T., E.M., M.C.
ACKNOWLEDGMENTS The authors thank Naomi Knoblauch for assistance with formatting, grammatical editing, and sourcing references, and Dr Jens Duehr (chiropractor/researcher) for translation of a key research paper from German into English.
Todd et al Forces of Chiropractic Techniques on Children
REFERENCES 1. Lee AC, Li DH, Kemper KJ. Chiropractic care for children. Arch Pediatr Adolesc Med. 2000;154(4):401-407. 2. Xue CL, Zhang AL, Lin V, Myers R, Polus B, Story D. Acupuncture, chiropractic and osteopathy use in Australia: A national population survey. BMC Public Health. 2008;8:105. 3. French S, Charity M, Forsdike K, et al. Chiropractic Observation and Analysis Study (COAST): providing an understanding of current chiropractic practice. Med J Aust. 2013;199(10):687-691. 4. Vohra S, Johnston BC, Cramer K, Humphreys K. Adverse events associated with pediatric spinal manipulation: a systematic review. Pediatrics. 2007;119(1):e275-e283. 5. Doyle MF. Is chiropractic paediatric care safe? A best evidence topic. Clin Chiropr. 2011;14(3):97-105. 6. Todd AJ, Carroll MT, Robinson A, Mitchell EKL. Adverse events from chiropractic and other manual therapies for infants and children: A Review of the Literature. J Manipulative Physiol Ther. 2015;38(9):699-712. 7. Hayworth N, Ebrall P. Undergraduate Paediatric Curriculum at RMIT School of Chiropractic 2010. Melbourne: RMIT University; 2010. 8. Johnson C. Evidence-based practice in 5 simple steps. J Manipulative Physiol Ther. 2008;31(3):169-170. 9. Garbutt J, Brownstein DR, Klein EJ, et al. Reporting and disclosing medical errors: pediatricians' attitudes and behaviors. Arch Pediatr Adolesc Med. 2007;161(2):179-185. 10. Loren DJ, Klein EJ, Garbutt J, et al. Medical error disclosure among pediatricians: choosing carefully what we might say to parents. Arch Pediatr Adolesc Med. 2008;162(10):922-927. 11. Hawk C, Schneider M, Ferrance RJ, Hewitt E, Van Loon M, Tanis L. Best practices recommendations for chiropractic care for infants, children, and adolescents: results of a consensus process. J Manipulative Physiol Ther. 2009;32(8):639-647. 12. Gleberzon BJ. Chiropractic name techniques in Canada: a continued look at demographic trends and their impact on issues of jurisprudence. J Can Chiropr Assoc. 2002;46(4): 241-256. 13. Pohlman KA, Hondras MA, Long CR, Haan AG. Practice patterns of doctors of chiropractic with a pediatric diplomate: a crosssectional survey. BMC Complement Altern Med. 2010;10:26. 14. Haavik-Taylor H, Holt K, Murphy B. Exploring the neuromodulatory effects of the vertebral subluxation and chiropractic care. Med J Aust. 2010;40(1):37-44. 15. Marchand AM. A proposed model with possible implications for safety and technique adaptations for chiropractic spinal manipulative therapy for infants and children. J Manipulative Physiol Ther. 2015;38(9):9713-9726. 16. Fuhr AW, Menke JM. Status of activator methods chiropractic technique, theory and practice. J Manipulative Physiol Ther. 2005;28(2):135.e1-135.e20. 17. Koch LE, Biedermann H, Saternus KS. High cervical stress and apnoea. Forensic Sci Int. 1998;97(1):1-9. 18. Koch LE, Koch H, Graumann-Brunt S, Stolle D, Ramirez JM, Saternus KS. Heart rate changes in response to mild mechanical irritation of the high cervical spinal cord region in infants. Forensic Sci Int. 2002;128(3):168-176. 19. Snodgrass SJ, Rivett DA, Robertson VJ. Manual forces applied during cervical mobilization. J Manipulative Physiol Ther. 2007;30(1):17-25. 20. Zegarra-Parodi R, De Chauvigny de Blot P, Rickards L, Renard E-O. Cranial palpation pressures used by osteopathy students: effects of standardized protocol training. J Am Osteopath Assoc. 2009;109(2):79-85.
9
10
Todd et al Forces of Chiropractic Techniques on Children
21. Graham BA, Clausen P, Bolton PS. A descriptive study of the force and displacement profiles of the toggle-recoil spinal manipulative procedure (adjustment) as performed by chiropractors. Man Ther. 2010;15(1):74-79. 22. Colloca CJ, Keller TS, Black P, Normand MC, Harrison DE, Harrison DD. Comparison of mechanical force of manually assisted chiropractic adjusting instruments. J Manipulative Physiol Ther. 2005;28(6):414-422. 23. Zemelka W, ed. The Thompson Technique. Bettendorf, IA: Victoria Press; 1992. 24. Liebschner MA, Chun K, Kim N, Ehni B. In vitro biomechanical evaluation of single impulse and repetitive mechanical shockwave devices utilized for spinal manipulative therapy. Ann Biomed Eng. 2014;42(12):2524-2536. 25. Marchand AM. Chiropractic care of children from birth to adolescence and classification of reported conditions: an Internet cross-sectional survey of 956 European chiropractors. J Manipulative Physiol Ther. 2012;35(5):372-380. 26. Herzog W. The biomechanics of spinal manipulation. J Bodyw Mov Ther. 2010;14(3):280-286. 27. Koch LE, Girnus U. Kraftmessung bei anwendung der impulstechink in der chirotherapie. Man Med. 1998;36(1):21-26. 28. Blum C. The compendium of SOT peer reviewed published literature from 1984-2000. J Vert Sublux Res. 2002;4:123. 29. Hayes NM, Bezilla TA. Incidence of iatrogenesis associated with osteopathic manipulative treatment of pediatric patients. J Am Osteopath Assoc. 2006;106(10):605-608. 30. Biedermann H. Manual therapy in children: proposals for an etiologic model. J Manipulative Physiol Ther. 2005;28(3):e1-e15. 31. Miller JE, Newell D, Bolton JE. Efficacy of chiropractic manual therapy on infant colic: a pragmatic single-blind, randomized controlled trial. J Manipulative Physiol Ther. 2012;35(8):600-607. 32. Alcantara J, Ohm J, Kunz D. The chiropractic care of children. J Altern Complement Med. 2010;16(6):621-626. 33. Wilson P, Greiner M, Duma E. Posterior rib fractures in a young infant who received chiropractic care. Pediatrics. 2012;130(5):1359-1362. 34. Fischer RS, Fuhr AW. Rebuttal of potential forces of instrument adjusting on an infant rib fracture. Pediatr eLett. 2013 [Viewed 13 August 2014. http://pediatrics.aappublications.org/content/ 130/5/e1359.comments#rebuttal-of-potential-forces-ofinstrument-adjusting-on-an-infant-rib-fracture].
Journal of Manipulative and Physiological Therapeutics Month 2016
35. Klougart N, Leboeuf-Yde C, Rasmussen LR. Safety in chiropractic practice. Part II: treatment to the upper neck and the rate of cerebrovascular incidents. J Manipulative Physiol Ther. 1996;19(9):563-569. 36. Rageot E. Complications and accidents in vertebral manipulation. Cah Coll Med Hop Paris. 1968;9(14):1149-1154. 37. Shafrir Y, Kaufman BA. Quadriplegia after chiropractic manipulation in an infant with congenital torticollis caused by a spinal cord astrocytoma. J Pediatr. 1992;120(2 Pt 1): 266-269. 38. Ziv I, Rang M, Hoffman HJ. Paraplegia in osteogenesis imperfecta. A case report. J Bone Joint Surg (Br). 1983; 65(2):184-185. 39. Zimmerman AW, Kumar AJ, Gadoth N, Hodges FJ. Traumatic vertebrobasilar occlusive disease in childhood. Neurology. 1978;28(2):185-188. 40. L'Ecuyer JL. Congenital occipitalization of the atlas with chiropractic manipulations: a case report. Nebr State Med J. 1959;44:546-550. 41. Christensen MG, Kollasch MW, Ward R, Webb K, Day A, ZumBrunnen JJ. Job Analysis of Chiropractic. Greeley, CO: National Board of Chiropractic Examiners; 2005. 42. Triano JJ, Descarreaux M, Dugas C. Review of approaches for performance training in spinal manipulation. J Electromyogr Kinesiol. 2012;22(5):5732-5739. 43. Descarreaux M, Dugas C. Learning spinal manipulation skills: assessment of biomechanical parameters in a 5-year longitudinal study. J Manipulative Physiol Ther. 2010;33(3): 226-230. 44. Cooperstein R. Technique system overview: Thompson technique. Chiropr Tech. 1995;7:60-63. 45. Rome PL. Medical management of pediatric and nonmusculoskeletal conditions by spinal manipulation. Med J Aust. 2013;43(4):131-136. 46. Johnson C, Rubinstein SM, Cote P, et al. Chiropractic care and public health: answering difficult questions about safety, care through the lifespan, and community action. J Manipulative Physiol Ther. 2012;35(7):493-513. 47. Hawk C, Schneider MJ, Vallone S, Hewitt EG. Best practices for chiropractic care of children: a consensus update. J Manipulative Physiol Ther. 2016;39(3):158-168, http://dx. doi.org/10.1016/j.jmpt.2016.02.015.