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Wrist pain in gymnasts: Efficacy of a wrist brace to decrease wrist pain while performing gymnastics
Journal of Hand Therapy xxx (2019) 1e6
Contents lists available at ScienceDirect
Journal of Hand Therapy journal homepage: www.jhandtherapy.org
Wrist pain in gymnasts: Efficacy of a wrist brace to decrease wrist pain while performing gymnastics Beverly Trevithick MAppSc (Biomedical) *, Rebecca Mellifont PhD, Mark Sayers PhD Department of Health and Sport Sciences, University of the Sunshine Coast, Queensland, Australia
a r t i c l e i n f o
a b s t r a c t
Article history: Received 15 September 2018 Received in revised form 7 February 2019 Accepted 3 March 2019 Available online xxx
Study Design: This was a clinical trial of prospective cohort. Introduction: Wrist pain in gymnasts is a global phenomenon. Compression forces acting on wrists while performing gymnastics is a predisposing factor in the development of wrist pain and consequential injury of the distal radial physis in skeletally immature gymnasts. One approach to mitigate these forces is wrist bracing; however, studies on the efficacy of wrist braces to reduce wrist pain experienced by gymnasts are limited. Purpose of the Study: The purpose of this study was to investigate the efficacy of an innovative design of a wrist brace to decrease gymnasts’ wrist pain while performing gymnastics. Methods: A wrist brace was designed and trialled over 3 weeks by 48 male gymnasts (aged 8-22 years, levels 4-7) with wrist pain. Wrist pain was recorded on a visual analog scale of 1 to 10 before and after trial. Data analysis was performed using SPSS-22 (IBM Inc). Paired t-tests were performed to compare variables before and after trial, with effect size analyses used to quantify the relative magnitude of any differences. Results: Paired t-tests indicated the gymnasts reported significantly reduced pain (P ¼ .002; 53.5%) while wearing the braces for training on the pommel, floor, and parallel bars. The overall large effect size value was practically significant (d ¼ 0.902). Discussion: For any wrist brace to be effective, it needs to be implemented when the gymnast experiences wrist pain before an injury occurs. This would minimize the development of pain-provoked adaptive movement patterns that perpetuate dysfunction. Conclusions: The brace with the volar gel pad is recommended to be worn as an adjunct to current strategies in management of gymnasts’ wrist pain or as an injury prevention device in skeletally immature gymnasts. Ó 2019 Hanley & Belfus, an imprint of Elsevier Inc. All rights reserved.
Keywords: Radial physis Adolescent Wrist Ground reaction forces Gymnast Wrist brace
Introduction Wrist pain in adolescent gymnasts is a common occurrence particularly during growth and development. Chronic wrist pain may result in an injury to the distal radial growth plate in the
Financial disclosure: No funding was received for this study. Conflict of interest: None. Approval for this study was granted by the Human Research Ethics Committee of the University of the Sunshine Coast (S/12/446), Qld, Australia. All participants in the trial were required to sign a consent form, or if under 18 years of age, consent form was signed by a parent or guardian. Each consenting participant was supplied with a project information sheet, pre- and post-trial pain questionnaire and the wrist braces. This manuscript submitted to this journal has not been published elsewhere or is not being considered for publication elsewhere and the research reported will not be submitted for publication elsewhere until a final decision has been made to its acceptability to this journal. * Corresponding author. Department of Health and Sport Sciences, University of the Sunshine Coast, Queensland, Australia. Tel.: þ61 468436238. E-mail address: [email protected] (Beverly Trevithick).
skeletally immature gymnast, with global studies identifying wrist injuries between 46% and 87% of all injuries recorded.1-3 A recent survey of Australian gymnasts (aged 10-18 years) reported a lifetime prevalence of wrist pain of 92.6% and a point prevalence of 70.6%.4 Over the last 10 years, gymnastic injury prevention strategies have investigated functions and features of mat design,5 including the effectiveness of multilayer landing mats to minimize ground reaction forces,6 modeling apparatus impact energy,7 and energy of wrist analysis and surface rebound.8 These studies have been the catalyst for upgrading apparatus standards, but there has been no studies on wrist brace design to reduce the impact force of the hand contact with the apparatus to decrease the development of wrist pain. With the increasing number of children involved in gymnastics,9 the incidence of wrist pain can only increase. One of the countermeasures in reducing the incidence of gymnast’s wrist pain, and any wrist injury, is by wearing wrist braces. There have been numerous studies on the efficacy of wrist braces for the prevention of wrist fractures and soft-tissue injuries
0894-1130/$ e see front matter Ó 2019 Hanley & Belfus, an imprint of Elsevier Inc. All rights reserved. https://doi.org/10.1016/j.jht.2019.03.002
2
B. Trevithick et al. / Journal of Hand Therapy xxx (2019) 1e6
in inline skating, hockey, skate boarding, and snowboarding, where wrist injuries account for 35 to 45% of all injuries recorded.10-16 However, there are few published studies on wrist braces worn by gymnasts,17,18 where the injury incidence recorded is higher. The wrist braces used in snow sports are designed to limit wrist extension and are considered to attenuate the wrist impact by absorbing and diverting the forces when there is a fall onto an outstretched hand.19 This is achieved through brace rigidity often with both dorsal and volar padding to protect bone and soft tissue during falls. Weight-bearing through outstretched hands while performing gymnastics is comparable with falling on outstretched hands as experienced in snowboarding.19 However, gymnasts expose their wrists to high-impact, repetitive, axial compression loading and torsional stress, with the wrist in varying degrees of ulnar and radial deviation and hyperextension, while weightbearing through their hands.20 Hence, the wrist braces generally worn by gymnasts are aimed at restricting wrist hyperextension to prevent carpal abutment, dorsal impingement, and soft-tissue injuries. These outcomes are achieved by plastic and Ethafoam (Dow Chemical Company) padding materials inserted in pockets on the dorsum of the wrist braces. The thickness of the inserts is variable, allowing the gymnasts to have some control over their wrist range of extension by inserting appropriate thickness of padding. Therefore, although these braces do restrict hyperextension and reduce the incidence of dorsal injury, they do not address the volar compression forces acting on the wrist. Research in snow sports has determined that better energy absorption occurs with volar padding materials12 and wearing wrist braces was effective in decreasing injuries in adolescents and those learning the sport.16 Studies have investigated several types of palmar padding, such as gel and Ethafoam and combinations of these, in commercially available braces.21,22 Analysis of cadaveric studies found that wrist braces with volar padding were effective in both load sharing and absorption of impact energy23 and assisted in the dissipation of forces through the wrist and contributed to the prevention of ligament tears in low-energy impact falls onto an outstretched hand.24 Although many gymnasts wear wrist braces due to the repetitive ‘falls onto outstretched hands’ required to perform gymnastic skills,25 there is limited research on the efficacy of wrist braces available for gymnasts.17,18 Based on evidence from prior research11,12,21,22,26,27 and feedback from treating gymnasts with wrist pain, a ‘volar carpal force dissipation wrist brace’ for gymnasts was designed. It included a volar gel pad to absorb and dissipate the compression forces acting on the wrist, with the aim to decrease wrist pain and the possible consequence of wrist injury while performing gymnastics.
trial. The gymnasts who agreed to participate in the trial signed a consent form. Those younger than 18 years required the consent form to be signed by a parent or guardian. The volar carpal force dissipation wrist brace design was based on a neoprene wrist wrap, with thumbhole extending from the distal palmar crease to 2 cm proximal to the wrist crease (Figs. 1-3). The thumb was placed through the thumbhole, and the brace wrapped around the palm to the dorsum, underneath the metacarpal heads, and attached with Velcro straps (The VelcroÒ Brand) on the ulnar side of the wrist. ‘Shark skin’ neoprene (3.2 mm) was the fabric of choice because it is a synthetic polymer fiber with properties including shock absorption, which is soft, flexible, stretchable, and is both washable and durable. The outer side, which has contact with the apparatus, was the ‘shark skin’ side for grip, and the inner side was a plain black fabric. The brace pattern was cut in one piece with a thumbhole placed 1.5 cm below the distal palmar crease in line with the web space. Velcro straps secured the brace in a circumferential manner. A black 2-mm-thick neoprene pocket was sewn into the volar part of the brace. The pocket covered the entire volar aspect of the wrist extending from the volar wrist crease distally 2-3 cm and proximally 4 to 5 cm relative to the brace size (Fig. 1). The pocket was open at the distal end to allow removal of the gel for washing. The 4.8-mm gel pad (Akton polymer; Action Products, MD) was incorporated into the pocket of the wrist brace to assist in the dissipation of compression forces over the carpus. This gel material was chosen for its specifications, which included the ability to deflect applied load, absorb shock, dampen vibration, and reduce any heat buildup between gel and neoprene due to friction and shear. It does not support bacterial growth, is hypoallergenic, evenly distributes weight, retains its shape, and is easily cleaned. Braces were made in 3 sizes, fitting gymnasts from 8 years to 25 years: small (wrist circumference measurement 11-13 cm), medium (13-15 cm), and large (15-18 cm). Instructions on brace care were included. The wrist braces were fitted, and pain evaluation form explained and provided to the participants (Fig. 4). The pain evaluation form was filled out twice, once before trial and then immediately after the 3-week trial, to determine whether
Methods Gymnasts were recruited via emailing gymnastic clubs and after personal contact with coaches. Criteria for participation were as follows: (1) aged between 8 and 25 years; (2) having wrist pain in one or both wrists which only occurred when participating in gymnastics (ie, subjects were to have no wrist pain for functional activities of daily living or activities other than gymnastics); (3) no current medical condition involving wrists/hands, elbows, or shoulders; and (4) consent to undergo a musculoskeletal assessment of upper limbs by an experienced physiotherapist. The fourth condition was necessary to screen out gymnasts who demonstrated signs and symptoms of current wrist or upper limb injury who were deemed to require specific treatment (which thereby excluded the gymnast from the trial). The criteria for the trial were discussed with each gymnast before the trial to ensure they had full understanding of the expectations. Any gymnast who decided at any time that they did not want to remain involved was removed from the
Fig. 1. Volar carpal force dissipation wrist brace, volar view.
B. Trevithick et al. / Journal of Hand Therapy xxx (2019) 1e6
3
compression, as opposed to the other 4 apparatus that involve more consistent wrist compression loading. The order of transition was observed to be random. The assignment of the gymnasts to the starting apparatus at each training session was random; (2) gymnasts named the apparatus on which they experienced wrist pain (could record more than one); and (3) whether wrist pain was experienced mid dorsal, mid volar, radial, or ulnar (could record more than one area). Gymnasts were requested to wear the braces for all training over the 3-week trial. Pain was evaluated on a modified visual analog scale of 0 to 10 specified as follows: 0 ¼ had no pain at all, 1 to 5 ¼ pain on an activity but goes away when activity is ceased, 6 to 9 ¼ pain is still present when activity is ceased, taking up to 5 min to resolve, and 10 ¼ pain prevented performance of the activity. Men’s Artistic Gymnastics (MAG) levels in Australia comprised MAG level 1 to 10, incorporating club and national gymnasts. Beyond MAG, gymnasts move into senior international training levels. Gymnasts aged 9 to 15 years generally fall within levels 4 to 7. The data were analyzed using SPSS-22 (IBM Inc). Descriptive statistics and paired t-tests were performed to compare variables of age, level, and apparatus and determine pain levels experienced before and after trial, with Cohen’s d effect size analyses used to quantify the relative magnitude of any differences. Results Fig. 2. Volar carpal force dissipation wrist brace, lateral view.
wrist pain during activity had changed due to the wearing of the brace. Gymnasts recorded 3 aspects: (1) the level of pain experienced while wearing the braces when performing their normal training. This involved a training circuit of 4 apparatus: pommel, vault, floor, and parallel bars. Rings and high bar were not included because they apply more traction forces to wrist with intermittent
A total of 48 club- and national-level male gymnasts (aged 10-22 years) who experienced wrist pain while performing gymnastics completed the trials. The mean age was 12.5 years, mean number of hours trained per week was 11 hours, and mean training was level 5. A significant decrease in pain in mid dorsum, mid volar, and ulnar areas of the wrist was found, where Cohen’s effect size value suggested high practical significance. Although the radial (thumb) side recorded no significant reduction in pain on the P value, there was a high practical effect size (d ¼ 0.87) (Table 1). An independent t-test showed the gymnasts aged 10 to 14 years who trained in the levels 4 to 7 had significantly reduced wrist pain (P ¼ .029) while wearing the braces when training on the pommel. A paired t-test comparing the overall wrist pain before and after wearing the braces found a significant (P ¼ .002, d ¼ 0.902) decrease in pain levels (53.5%) when performing on the floor, pommel, and parallel bars (Table 2). None of the gymnasts indicated pain on the vault. Further correlations between age and training hours found no significant difference between these variables and wrist pain before and after trial. Gymnasts who completed the trial reported that the braces were comfortable, easy to put on and take off, and easy to clean. Follow-up with the gymnasts after the trial found that 42 of the 48 gymnasts continued to use their braces whenever they experienced wrist pain because they perceived that the braces either decreased or resolved their wrist pain when performing on specific apparatus (pommel, floor, or parallel bars). The elite gymnasts trialled found that the brace over their palm prevented speed and dexterity, specifically on the handles of the pommel, which stopped them from uptake of this brace. Discussion
Fig. 3. Volar carpal force dissipation wrist brace, dorsal view.
Preventing or ameliorating wrist pain in adolescent gymnasts depends on identifying the factors that predispose the wrist growth plates to injury and being able to put into place strategies to overcome these factors. The ground reaction forces that the wrist is subjected to while performing gymnastics have been identified as a predisposing cause in the development of wrist pain in gymnasts.28 Based on prior biomechanical testing21,29 in
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Fig. 4. Wrist pain evaluation form for braces trial.
sports braces which found the addition of various volar padding substantially reduced impact force, the positioning of the gel pad in this brace is believed to have assisted in dissipating the compression forces on the wrist by acting as a ‘cushion’. Repetitive submaximal loading acting on the wrist may compromise Table 1 Changes, significance, and effect size of wrist pain (by pain area) experienced before and after trial (paired t-test) VAS Pain area Mid dorsum Mid volar Radial Ulnar
n (%) 40 3 20 12
(83.3) (6.2) (41.6) (20.8)
Before
After
P
Effect size
Mean SD
Mean SD
p ¼ <.05
Cohen’s d
4.62 5.39 5.04 5.20
1.50 1.36 1.48 1.49
1.71 2.47 2.12 2.29
1.91 1.89 1.86 2.07
VAS ¼ visual analog scale; SD ¼ standard deviation.
.054 .035 .072 .008
0.74 0.89 0.87 0.86
the distal radial physis in gymnasts during growth spurts, causing premature closing of the growth plate. The normal wrist joint alignment is then lost as the ulna keeps growing relative to the radius, resulting in positive ulnar variance. In gymnasts, positive ulnar variance leads to increased carpal loading and is associated
Table 2 Changes, significance, and effect size of wrist pain experienced on the apparatus before and after trial (paired t-test) VAS
Before
After
P
Effect size
Apparatus
n (%)
Mean SD
Mean SD
p ¼ <.05
Cohen’s d
Pommel Floor Parallel bars
37 (78.7) 10 (20.8) 2 (4)
5.78 1.26 4.50 1.08 4.00 1.4
2.65 2.03 2.20 1.23 3.50 2.12
.000 .003 .029
0.95 0.99 0.14
VAS ¼ visual analog scale; SD ¼ standard deviation.
B. Trevithick et al. / Journal of Hand Therapy xxx (2019) 1e6
with ulnar impaction syndrome, triangular fibrocartilage complex, lunate-triquetral ligament tears, and chondral injury to the lunate.30-32 This is relevant in our study because 82% of the participants aged 9 to 14 years (and males younger than 18 years are considered skeletally immature). In 20% of males, the distal radial physis starts closure at 15 to 16 years and does not fully ossify until 18 to 20 years.33 Male gymnasts in this age range who perform with perpetual wrist pain are at risk of injury because they rarely report niggling injuries for fear of losing face or letting the team or coach down and are therefore not often evaluated and appropriately managed. It is this vulnerable age group that needs to be monitored, educated of the consequences of long-term wrist pain, and encouraged to report any wrist pain experienced when performing gymnastics. Any stress-induced changes in the distal radius due to compression loading are well documented in cases where the gymnast suffers from painful wrists.34 Wrist injuries without radiographic changes heal within a month, whereas those with changes require 3 months of rest before becoming asymptomatic and often up to 12 months for the bone to heal.35 If distal radial or ulnar growth plates have been impaired, the gymnast may develop permanent effects of progressive deformity and degenerative joint disease.36,37 It is during growth spurts in the younger gymnasts that the radial and ulnar growth plates are most vulnerable to injury. Injury may occur from one isolated incident exceeding a gymnast’s tissues maximum tolerance or through long-term loading. Therefore, during growth periods, the male gymnasts younger than 18 years who report experiencing wrist pain when performing gymnastics may benefit from a wrist brace, such as that trialled, to decrease wrist pain and prevent any subsequent injury. For any wrist brace to be most effective, it needs to be worn when the gymnast experiences initial pain and before an injury occurs. Wearing a brace during the vulnerable stages of growth will allow the growing gymnast’s upper limbs time to develop and strengthen, further protecting the gymnast from wrist pain and pain-provoked movement pattern imbalances that perpetuate the dysfunction.38 The design of the volar carpal force dissipation wrist brace is based on an understanding that there are compression forces acting on adolescent gymnasts’ wrists when performing gymnastics. Although the thickness of the brace material does restrict full range of wrist hyperextension, it neither fully immobilizes the wrist nor restricts hand function, but the volar gel pad assists in mitigating the forces the wrist is subject to during gymnastic activity. Conclusions The volar carpal force dissipation wrist brace has been shown to be effective in significantly decreasing overall wrist pain in male gymnasts (aged 10-14 years, levels 4-7) while performing on the apparatus of pommel, floor, and parallel bars. It is therefore recommended that male gymnasts aged 10 to 14 years consider the use of volar carpal force dissipation wrist brace to minimize wrist pain experienced while performing gymnastic activity and assist as an injury preventative measure. Limitations and suggestions The gymnasts who volunteered to participate in the brace trial consented to a musculoskeletal assessment. Because all had wrist pain, the assessment excluded any gymnasts from the trial who were assessed as having any wrist instability or general musculoskeletal injuries that required specific treatment or could be aggravated by the trial (and these gymnasts were referred on for further investigation). This fact influenced numbers for the trial.
5
Five elite male gymnasts were initially recruited (aged 22-25 years). However, they advised that any wrist brace that covered the palm of the hand was unlikely to be worn by gymnasts at their level because it affected their performance technique and proprioception and the gel pad was uncomfortable. They subsequently withdrew from the study. Considering that the pommel is named as the apparatus predisposing wrist pain in elite gymnasts, further investigation into strategies to reduce the prevalence of wrist pain during gymnastic activity in this cohort is worthy of consideration. No female gymnasts or Women’s Artistic Gymnast coaches volunteered for the trials despite widespread recruiting to gymnastic clubs by letter, posters, and personal contact with coaches. For further investigations into effective bracing for gymnast’s wrists, both females and males performing across all levels of gymnastics need to be included. Investigation into comparing the dissipation of ground reaction forces between the braced and unbraced wrists would further validate the wearing of a wrist brace, such as that designed and trialled in this study.
Acknowledgments Without the enthusiasm of the Men’s Artistic Gymnastics coaches and the gymnasts who volunteered for the brace trial, this research would not have been possible. The authors thank Bev Quee for her assistance, knowledge, and support throughout the stages of brace concept, design, and pilot testing.
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18. Neal R, Kippers V, Plooy D, Forwood M. The influence of hand guards on forces and muscle activity during giant swings on the high bar. Med Sci Sports Exerc. 1995;27(11):1550e1556. 19. Burkhart T, Andrews D. The effectiveness of wrist guards for reducing wrist and elbow accelerations resulting from simulated foreard falls. J Appl Biomech. 2010;26(3):281e289. 20. Webb B, Rettig L. Gymnastic wrist injuries. Curr Sports Med Rep. 2008;7(5): 289e295. 21. Hwang I, Kim K. Shock absorbing effects of various padding conditions in improving efficacy of wrist guards. J Sports Sci Med. 2004;3:23e29. 22. Hwang S, Kim K, Kaufman K, Cooney W, An K. Biomechanical efficiency of wrist guards as a shock isolator. J Biomech Eng. 2006;128(2):229e234. 23. Staebler M, Moore D, Akelman M, Weiss A, Fadale P, Crisco J. The effect of wrist guards on bone strain in the distal forearm. Am J Sports Med. 1999;27(4):500e 506. 24. Greenwald M, Chu J, Jessiman W. Dynamic wrist joint protector for sports applications. In: Moritz E, Haake S, eds. The Engineering of Sport 6: Development for Innovation. vol. 3. New York, NY: Springer; 2006:157e162. 25. Di Fiori J. Overuse injury and the young athlete: the case of the chronic wrist pain in the gymnast. Curr Sports Med Rep. 2006;5:165e167. 26. Choi W, Robinovitch S. Pressure distribution over the palm region during forweard falls on the outstretched hands. J Biomech. 2011;44:532e539. 27. Kim S, Lee S. Snowboard wrist guards - use, efficacy and design. Bull NYU Hosp Jt Dis. 2011;69(2):149e157.
28. Bradshaw E, Hume P. Biomechanical approaches to identify and quantify injury mechanisms and risk factors in women’s artistic gymnastics. Sports Biomech. 2012;11(3):324e341. 29. Maurel M, Fitzgerald L, Miles A, Giddins G. Biomechanical study of the efficacy of a new design of wrist guard. Clin Biomech. 2013;28:509e513. 30. De Smet L, Claessens A, Fabry G. Gymnast wrist. Acta Orthop Belg. 1994;59(4): 377e380. 31. Little J, Klionsky N, Chaturvedi A, Soral A, Chaturvedi A. Paediatric distal forearm and wrist injury: an imaging review. Radiographics. 2014;34(2):472e490. 32. Tolat A, Sanderson P, De Smet L, Stanley J. The gymnast’s wrist: acquired positive ulna variance following chronic epiphyseal injury. J Hand Surg Br. 1992;17 B:678e681. 33. Hassan N, Noor F, Ahmad S, Fazili KM. Age of fusion of the distal radial and ulnar epiphyses from hand radiographs - a study in Kashmiri population. Sci Justice. 2016;56(6):431e436. 34. Dwek JR, Cordoso F, Chung C. MR imaging of overuse injuries in the skeletally immature gymnast: a spectrum of soft -tissue and osseus lesions in the hand and wrist. Pediatr Radiol. 2009;39:1301e1316. 35. Zetaruk M. The young gymnast. Clin Sports Med. 2000;19(4):757e780. 36. Di Fiori J, Caine D, Malina R. Wrist pain, distal radial physeal injury, and ulnar variance in the young gymnast. Am J Sports Med. 2006;34(5):840e849. 37. Maffulli N, Bruns W. Injuries in young athletes. Eur J Pediatr. 2000;159:59e63. 38. Hodges P, Tucker K. Moving differently in pain: a new theory to explain adaptation of pain. Pain. 2011;152(Suppl):S90eS98.
Contents lists available at ScienceDirect
Journal of Hand Therapy journal homepage: www.jhandtherapy.org
Wrist pain in gymnasts: Efficacy of a wrist brace to decrease wrist pain while performing gymnastics Beverly Trevithick MAppSc (Biomedical) *, Rebecca Mellifont PhD, Mark Sayers PhD Department of Health and Sport Sciences, University of the Sunshine Coast, Queensland, Australia
a r t i c l e i n f o
a b s t r a c t
Article history: Received 15 September 2018 Received in revised form 7 February 2019 Accepted 3 March 2019 Available online xxx
Study Design: This was a clinical trial of prospective cohort. Introduction: Wrist pain in gymnasts is a global phenomenon. Compression forces acting on wrists while performing gymnastics is a predisposing factor in the development of wrist pain and consequential injury of the distal radial physis in skeletally immature gymnasts. One approach to mitigate these forces is wrist bracing; however, studies on the efficacy of wrist braces to reduce wrist pain experienced by gymnasts are limited. Purpose of the Study: The purpose of this study was to investigate the efficacy of an innovative design of a wrist brace to decrease gymnasts’ wrist pain while performing gymnastics. Methods: A wrist brace was designed and trialled over 3 weeks by 48 male gymnasts (aged 8-22 years, levels 4-7) with wrist pain. Wrist pain was recorded on a visual analog scale of 1 to 10 before and after trial. Data analysis was performed using SPSS-22 (IBM Inc). Paired t-tests were performed to compare variables before and after trial, with effect size analyses used to quantify the relative magnitude of any differences. Results: Paired t-tests indicated the gymnasts reported significantly reduced pain (P ¼ .002; 53.5%) while wearing the braces for training on the pommel, floor, and parallel bars. The overall large effect size value was practically significant (d ¼ 0.902). Discussion: For any wrist brace to be effective, it needs to be implemented when the gymnast experiences wrist pain before an injury occurs. This would minimize the development of pain-provoked adaptive movement patterns that perpetuate dysfunction. Conclusions: The brace with the volar gel pad is recommended to be worn as an adjunct to current strategies in management of gymnasts’ wrist pain or as an injury prevention device in skeletally immature gymnasts. Ó 2019 Hanley & Belfus, an imprint of Elsevier Inc. All rights reserved.
Keywords: Radial physis Adolescent Wrist Ground reaction forces Gymnast Wrist brace
Introduction Wrist pain in adolescent gymnasts is a common occurrence particularly during growth and development. Chronic wrist pain may result in an injury to the distal radial growth plate in the
Financial disclosure: No funding was received for this study. Conflict of interest: None. Approval for this study was granted by the Human Research Ethics Committee of the University of the Sunshine Coast (S/12/446), Qld, Australia. All participants in the trial were required to sign a consent form, or if under 18 years of age, consent form was signed by a parent or guardian. Each consenting participant was supplied with a project information sheet, pre- and post-trial pain questionnaire and the wrist braces. This manuscript submitted to this journal has not been published elsewhere or is not being considered for publication elsewhere and the research reported will not be submitted for publication elsewhere until a final decision has been made to its acceptability to this journal. * Corresponding author. Department of Health and Sport Sciences, University of the Sunshine Coast, Queensland, Australia. Tel.: þ61 468436238. E-mail address: [email protected] (Beverly Trevithick).
skeletally immature gymnast, with global studies identifying wrist injuries between 46% and 87% of all injuries recorded.1-3 A recent survey of Australian gymnasts (aged 10-18 years) reported a lifetime prevalence of wrist pain of 92.6% and a point prevalence of 70.6%.4 Over the last 10 years, gymnastic injury prevention strategies have investigated functions and features of mat design,5 including the effectiveness of multilayer landing mats to minimize ground reaction forces,6 modeling apparatus impact energy,7 and energy of wrist analysis and surface rebound.8 These studies have been the catalyst for upgrading apparatus standards, but there has been no studies on wrist brace design to reduce the impact force of the hand contact with the apparatus to decrease the development of wrist pain. With the increasing number of children involved in gymnastics,9 the incidence of wrist pain can only increase. One of the countermeasures in reducing the incidence of gymnast’s wrist pain, and any wrist injury, is by wearing wrist braces. There have been numerous studies on the efficacy of wrist braces for the prevention of wrist fractures and soft-tissue injuries
0894-1130/$ e see front matter Ó 2019 Hanley & Belfus, an imprint of Elsevier Inc. All rights reserved. https://doi.org/10.1016/j.jht.2019.03.002
2
B. Trevithick et al. / Journal of Hand Therapy xxx (2019) 1e6
in inline skating, hockey, skate boarding, and snowboarding, where wrist injuries account for 35 to 45% of all injuries recorded.10-16 However, there are few published studies on wrist braces worn by gymnasts,17,18 where the injury incidence recorded is higher. The wrist braces used in snow sports are designed to limit wrist extension and are considered to attenuate the wrist impact by absorbing and diverting the forces when there is a fall onto an outstretched hand.19 This is achieved through brace rigidity often with both dorsal and volar padding to protect bone and soft tissue during falls. Weight-bearing through outstretched hands while performing gymnastics is comparable with falling on outstretched hands as experienced in snowboarding.19 However, gymnasts expose their wrists to high-impact, repetitive, axial compression loading and torsional stress, with the wrist in varying degrees of ulnar and radial deviation and hyperextension, while weightbearing through their hands.20 Hence, the wrist braces generally worn by gymnasts are aimed at restricting wrist hyperextension to prevent carpal abutment, dorsal impingement, and soft-tissue injuries. These outcomes are achieved by plastic and Ethafoam (Dow Chemical Company) padding materials inserted in pockets on the dorsum of the wrist braces. The thickness of the inserts is variable, allowing the gymnasts to have some control over their wrist range of extension by inserting appropriate thickness of padding. Therefore, although these braces do restrict hyperextension and reduce the incidence of dorsal injury, they do not address the volar compression forces acting on the wrist. Research in snow sports has determined that better energy absorption occurs with volar padding materials12 and wearing wrist braces was effective in decreasing injuries in adolescents and those learning the sport.16 Studies have investigated several types of palmar padding, such as gel and Ethafoam and combinations of these, in commercially available braces.21,22 Analysis of cadaveric studies found that wrist braces with volar padding were effective in both load sharing and absorption of impact energy23 and assisted in the dissipation of forces through the wrist and contributed to the prevention of ligament tears in low-energy impact falls onto an outstretched hand.24 Although many gymnasts wear wrist braces due to the repetitive ‘falls onto outstretched hands’ required to perform gymnastic skills,25 there is limited research on the efficacy of wrist braces available for gymnasts.17,18 Based on evidence from prior research11,12,21,22,26,27 and feedback from treating gymnasts with wrist pain, a ‘volar carpal force dissipation wrist brace’ for gymnasts was designed. It included a volar gel pad to absorb and dissipate the compression forces acting on the wrist, with the aim to decrease wrist pain and the possible consequence of wrist injury while performing gymnastics.
trial. The gymnasts who agreed to participate in the trial signed a consent form. Those younger than 18 years required the consent form to be signed by a parent or guardian. The volar carpal force dissipation wrist brace design was based on a neoprene wrist wrap, with thumbhole extending from the distal palmar crease to 2 cm proximal to the wrist crease (Figs. 1-3). The thumb was placed through the thumbhole, and the brace wrapped around the palm to the dorsum, underneath the metacarpal heads, and attached with Velcro straps (The VelcroÒ Brand) on the ulnar side of the wrist. ‘Shark skin’ neoprene (3.2 mm) was the fabric of choice because it is a synthetic polymer fiber with properties including shock absorption, which is soft, flexible, stretchable, and is both washable and durable. The outer side, which has contact with the apparatus, was the ‘shark skin’ side for grip, and the inner side was a plain black fabric. The brace pattern was cut in one piece with a thumbhole placed 1.5 cm below the distal palmar crease in line with the web space. Velcro straps secured the brace in a circumferential manner. A black 2-mm-thick neoprene pocket was sewn into the volar part of the brace. The pocket covered the entire volar aspect of the wrist extending from the volar wrist crease distally 2-3 cm and proximally 4 to 5 cm relative to the brace size (Fig. 1). The pocket was open at the distal end to allow removal of the gel for washing. The 4.8-mm gel pad (Akton polymer; Action Products, MD) was incorporated into the pocket of the wrist brace to assist in the dissipation of compression forces over the carpus. This gel material was chosen for its specifications, which included the ability to deflect applied load, absorb shock, dampen vibration, and reduce any heat buildup between gel and neoprene due to friction and shear. It does not support bacterial growth, is hypoallergenic, evenly distributes weight, retains its shape, and is easily cleaned. Braces were made in 3 sizes, fitting gymnasts from 8 years to 25 years: small (wrist circumference measurement 11-13 cm), medium (13-15 cm), and large (15-18 cm). Instructions on brace care were included. The wrist braces were fitted, and pain evaluation form explained and provided to the participants (Fig. 4). The pain evaluation form was filled out twice, once before trial and then immediately after the 3-week trial, to determine whether
Methods Gymnasts were recruited via emailing gymnastic clubs and after personal contact with coaches. Criteria for participation were as follows: (1) aged between 8 and 25 years; (2) having wrist pain in one or both wrists which only occurred when participating in gymnastics (ie, subjects were to have no wrist pain for functional activities of daily living or activities other than gymnastics); (3) no current medical condition involving wrists/hands, elbows, or shoulders; and (4) consent to undergo a musculoskeletal assessment of upper limbs by an experienced physiotherapist. The fourth condition was necessary to screen out gymnasts who demonstrated signs and symptoms of current wrist or upper limb injury who were deemed to require specific treatment (which thereby excluded the gymnast from the trial). The criteria for the trial were discussed with each gymnast before the trial to ensure they had full understanding of the expectations. Any gymnast who decided at any time that they did not want to remain involved was removed from the
Fig. 1. Volar carpal force dissipation wrist brace, volar view.
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3
compression, as opposed to the other 4 apparatus that involve more consistent wrist compression loading. The order of transition was observed to be random. The assignment of the gymnasts to the starting apparatus at each training session was random; (2) gymnasts named the apparatus on which they experienced wrist pain (could record more than one); and (3) whether wrist pain was experienced mid dorsal, mid volar, radial, or ulnar (could record more than one area). Gymnasts were requested to wear the braces for all training over the 3-week trial. Pain was evaluated on a modified visual analog scale of 0 to 10 specified as follows: 0 ¼ had no pain at all, 1 to 5 ¼ pain on an activity but goes away when activity is ceased, 6 to 9 ¼ pain is still present when activity is ceased, taking up to 5 min to resolve, and 10 ¼ pain prevented performance of the activity. Men’s Artistic Gymnastics (MAG) levels in Australia comprised MAG level 1 to 10, incorporating club and national gymnasts. Beyond MAG, gymnasts move into senior international training levels. Gymnasts aged 9 to 15 years generally fall within levels 4 to 7. The data were analyzed using SPSS-22 (IBM Inc). Descriptive statistics and paired t-tests were performed to compare variables of age, level, and apparatus and determine pain levels experienced before and after trial, with Cohen’s d effect size analyses used to quantify the relative magnitude of any differences. Results Fig. 2. Volar carpal force dissipation wrist brace, lateral view.
wrist pain during activity had changed due to the wearing of the brace. Gymnasts recorded 3 aspects: (1) the level of pain experienced while wearing the braces when performing their normal training. This involved a training circuit of 4 apparatus: pommel, vault, floor, and parallel bars. Rings and high bar were not included because they apply more traction forces to wrist with intermittent
A total of 48 club- and national-level male gymnasts (aged 10-22 years) who experienced wrist pain while performing gymnastics completed the trials. The mean age was 12.5 years, mean number of hours trained per week was 11 hours, and mean training was level 5. A significant decrease in pain in mid dorsum, mid volar, and ulnar areas of the wrist was found, where Cohen’s effect size value suggested high practical significance. Although the radial (thumb) side recorded no significant reduction in pain on the P value, there was a high practical effect size (d ¼ 0.87) (Table 1). An independent t-test showed the gymnasts aged 10 to 14 years who trained in the levels 4 to 7 had significantly reduced wrist pain (P ¼ .029) while wearing the braces when training on the pommel. A paired t-test comparing the overall wrist pain before and after wearing the braces found a significant (P ¼ .002, d ¼ 0.902) decrease in pain levels (53.5%) when performing on the floor, pommel, and parallel bars (Table 2). None of the gymnasts indicated pain on the vault. Further correlations between age and training hours found no significant difference between these variables and wrist pain before and after trial. Gymnasts who completed the trial reported that the braces were comfortable, easy to put on and take off, and easy to clean. Follow-up with the gymnasts after the trial found that 42 of the 48 gymnasts continued to use their braces whenever they experienced wrist pain because they perceived that the braces either decreased or resolved their wrist pain when performing on specific apparatus (pommel, floor, or parallel bars). The elite gymnasts trialled found that the brace over their palm prevented speed and dexterity, specifically on the handles of the pommel, which stopped them from uptake of this brace. Discussion
Fig. 3. Volar carpal force dissipation wrist brace, dorsal view.
Preventing or ameliorating wrist pain in adolescent gymnasts depends on identifying the factors that predispose the wrist growth plates to injury and being able to put into place strategies to overcome these factors. The ground reaction forces that the wrist is subjected to while performing gymnastics have been identified as a predisposing cause in the development of wrist pain in gymnasts.28 Based on prior biomechanical testing21,29 in
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Fig. 4. Wrist pain evaluation form for braces trial.
sports braces which found the addition of various volar padding substantially reduced impact force, the positioning of the gel pad in this brace is believed to have assisted in dissipating the compression forces on the wrist by acting as a ‘cushion’. Repetitive submaximal loading acting on the wrist may compromise Table 1 Changes, significance, and effect size of wrist pain (by pain area) experienced before and after trial (paired t-test) VAS Pain area Mid dorsum Mid volar Radial Ulnar
n (%) 40 3 20 12
(83.3) (6.2) (41.6) (20.8)
Before
After
P
Effect size
Mean SD
Mean SD
p ¼ <.05
Cohen’s d
4.62 5.39 5.04 5.20
1.50 1.36 1.48 1.49
1.71 2.47 2.12 2.29
1.91 1.89 1.86 2.07
VAS ¼ visual analog scale; SD ¼ standard deviation.
.054 .035 .072 .008
0.74 0.89 0.87 0.86
the distal radial physis in gymnasts during growth spurts, causing premature closing of the growth plate. The normal wrist joint alignment is then lost as the ulna keeps growing relative to the radius, resulting in positive ulnar variance. In gymnasts, positive ulnar variance leads to increased carpal loading and is associated
Table 2 Changes, significance, and effect size of wrist pain experienced on the apparatus before and after trial (paired t-test) VAS
Before
After
P
Effect size
Apparatus
n (%)
Mean SD
Mean SD
p ¼ <.05
Cohen’s d
Pommel Floor Parallel bars
37 (78.7) 10 (20.8) 2 (4)
5.78 1.26 4.50 1.08 4.00 1.4
2.65 2.03 2.20 1.23 3.50 2.12
.000 .003 .029
0.95 0.99 0.14
VAS ¼ visual analog scale; SD ¼ standard deviation.
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with ulnar impaction syndrome, triangular fibrocartilage complex, lunate-triquetral ligament tears, and chondral injury to the lunate.30-32 This is relevant in our study because 82% of the participants aged 9 to 14 years (and males younger than 18 years are considered skeletally immature). In 20% of males, the distal radial physis starts closure at 15 to 16 years and does not fully ossify until 18 to 20 years.33 Male gymnasts in this age range who perform with perpetual wrist pain are at risk of injury because they rarely report niggling injuries for fear of losing face or letting the team or coach down and are therefore not often evaluated and appropriately managed. It is this vulnerable age group that needs to be monitored, educated of the consequences of long-term wrist pain, and encouraged to report any wrist pain experienced when performing gymnastics. Any stress-induced changes in the distal radius due to compression loading are well documented in cases where the gymnast suffers from painful wrists.34 Wrist injuries without radiographic changes heal within a month, whereas those with changes require 3 months of rest before becoming asymptomatic and often up to 12 months for the bone to heal.35 If distal radial or ulnar growth plates have been impaired, the gymnast may develop permanent effects of progressive deformity and degenerative joint disease.36,37 It is during growth spurts in the younger gymnasts that the radial and ulnar growth plates are most vulnerable to injury. Injury may occur from one isolated incident exceeding a gymnast’s tissues maximum tolerance or through long-term loading. Therefore, during growth periods, the male gymnasts younger than 18 years who report experiencing wrist pain when performing gymnastics may benefit from a wrist brace, such as that trialled, to decrease wrist pain and prevent any subsequent injury. For any wrist brace to be most effective, it needs to be worn when the gymnast experiences initial pain and before an injury occurs. Wearing a brace during the vulnerable stages of growth will allow the growing gymnast’s upper limbs time to develop and strengthen, further protecting the gymnast from wrist pain and pain-provoked movement pattern imbalances that perpetuate the dysfunction.38 The design of the volar carpal force dissipation wrist brace is based on an understanding that there are compression forces acting on adolescent gymnasts’ wrists when performing gymnastics. Although the thickness of the brace material does restrict full range of wrist hyperextension, it neither fully immobilizes the wrist nor restricts hand function, but the volar gel pad assists in mitigating the forces the wrist is subject to during gymnastic activity. Conclusions The volar carpal force dissipation wrist brace has been shown to be effective in significantly decreasing overall wrist pain in male gymnasts (aged 10-14 years, levels 4-7) while performing on the apparatus of pommel, floor, and parallel bars. It is therefore recommended that male gymnasts aged 10 to 14 years consider the use of volar carpal force dissipation wrist brace to minimize wrist pain experienced while performing gymnastic activity and assist as an injury preventative measure. Limitations and suggestions The gymnasts who volunteered to participate in the brace trial consented to a musculoskeletal assessment. Because all had wrist pain, the assessment excluded any gymnasts from the trial who were assessed as having any wrist instability or general musculoskeletal injuries that required specific treatment or could be aggravated by the trial (and these gymnasts were referred on for further investigation). This fact influenced numbers for the trial.
5
Five elite male gymnasts were initially recruited (aged 22-25 years). However, they advised that any wrist brace that covered the palm of the hand was unlikely to be worn by gymnasts at their level because it affected their performance technique and proprioception and the gel pad was uncomfortable. They subsequently withdrew from the study. Considering that the pommel is named as the apparatus predisposing wrist pain in elite gymnasts, further investigation into strategies to reduce the prevalence of wrist pain during gymnastic activity in this cohort is worthy of consideration. No female gymnasts or Women’s Artistic Gymnast coaches volunteered for the trials despite widespread recruiting to gymnastic clubs by letter, posters, and personal contact with coaches. For further investigations into effective bracing for gymnast’s wrists, both females and males performing across all levels of gymnastics need to be included. Investigation into comparing the dissipation of ground reaction forces between the braced and unbraced wrists would further validate the wearing of a wrist brace, such as that designed and trialled in this study.
Acknowledgments Without the enthusiasm of the Men’s Artistic Gymnastics coaches and the gymnasts who volunteered for the brace trial, this research would not have been possible. The authors thank Bev Quee for her assistance, knowledge, and support throughout the stages of brace concept, design, and pilot testing.
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