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Effectiveness of specific soft tissue mobilizations for the management of Achilles tendinosis: Single case study—Experimental design
ARTICLE IN PRESS
Manual Therapy 12 (2007) 63–71 www.elsevier.com/locate/math
Original article
Effectiveness of specific soft tissue mobilizations for the management of Achilles tendinosis: Single case study—Experimental design Rebecca E. Christenson,1 Pure Sports Medicine, David Lloyd Club, Point West, 116 Cromwell Road, Kensington, London SW7 4XR, UK Received 6 January 2005; received in revised form 22 January 2006; accepted 15 February 2006
Abstract A single case study ABA design was used to evaluate the effectiveness of a treatment protocol of accessory and combined specific soft tissue mobilizations (SSTMs) in a 39-year-old female with a 5-year history of Achilles tendinosis. The study involved three phases each lasting 6 weeks: a pre-treatment, treatment and post-treatment phase. There was also a 3-month follow-up after the post-treatment phase. The VISA A questionnaire was used as a severity index for Achilles tendinosis to quantify symptoms and dysfunction. A visual analogue scale (VAS) was used to record pain. Dorsiflexion range was measured using a goniometer with the knee extended to reflect gastrocnemius length and a weight-bearing dorsiflexion lunge test was used as a measure for soleus length. Following treatment, considerable improvements were recorded in all outcomes. The subject returned to a full gym programme and recorded no pain on the VAS as well as scoring 100% on the index of severity for Achilles tendinosis during the post-treatment phase and follow-up. The single case study design limits generalization but the results support the use of SSTMs in the treatment of Achilles tendinosis and suggests that further research into this intervention is warranted. r 2006 Elsevier Ltd. All rights reserved. Keywords: Achilles tendinosis; Specific soft tissue mobilizations; Single case study
1. Introduction Achilles tendinosis involves pathological changes to the tendon, characterized by an absence of inflammatory cells (A˚stro¨m and Rausing, 1995; Khan et al., 1999). Achilles tendon disorders are common, particularly in sporting individuals but can occur in those with a sedentary lifestyle (Alfredson and Lorentzon, 2000). The history often involves overuse either by a sudden increase in training or sustained high-level training (Kannus, 1997; Almekinders and Temple, 1998). Symptoms are aggravated by activities that load the Achilles tendon, commonly running (McCrory Tel.: +870 2000 878.
E-mail address: [email protected]. Research carried out at: Hammersmith Hospital, DuCane Road, London W12 0HS, UK. 1
1356-689X/$ - see front matter r 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2006.02.012
et al., 1999; Humble and Nugent, 2001; Kader et al., 2002; Paavola et al., 2002). These patients often have pain on and off for many years. Rest can ease the symptoms but is normally insufficient to allow return to the aggravating activity (Kvist, 1994; Maffulli and Kader, 2002). The pathogenesis is not entirely understood but mechanical load placed on the tendon, whether excessive or moderate, seems to result in microtrauma. The tendon then responds poorly with slow or incomplete healing and lacks extracellular organization (Cook et al., 2002). Normal tendon fibres are composed of predominantly type I collagen (Hayem, 2001). Histology of pathologic Achilles tendons have shown a chronic increase in type III collagen as well as disordered fibre arrangement (Ja¨rvinen et al., 1997; Khan et al., 1999; Maffulli et al., 2000; Eriksen et al., 2002). This thinner and less durable collagen compromises the function of the tendon and its ability to withstand load. Adding to
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this picture of mechanical disadvantage are the observations of increased mucoid ground substance, abnormal appearance and activity of tenocytes and neovascularization (A˚stro¨m and Rausing, 1995; Movin et al., 1997; Khan and Maffulli, 1998; Cook et al., 2001). Conservative management remains a challenge because of the deficient tendon repair and incomplete understanding of the pathology. Despite this, there does seem to be reasonable evidence for heavy-load eccentric calf muscle training in the management of Achilles tendinosis (Alfredson et al., 1998). A rational for this is that exercise may be able to affect and improve extracellular organization (Kannus et al., 1997; Wren et al., 2000). Convincing evidence behind manual therapy treatment of acute soft tissue injuries or tendinopathies is scant. However, empirically, the use of mobilizations to produce a mechanical effect has been advocated. Hunter (1994) developed specific soft tissue mobilizations (SSTMs) which tension the soft tissue via accessory soft tissue movement, physiological joint motion or a combination of both techniques. Hunter (1998) proposed a mechanical model to explain the potential effects of SSTM, suggesting that they may increase collagen synthesis and improve collagen alignment. There is evidence that application of a specific force to healing tissue can increase fibroblast activation (Davidson et al., 1997; Gehlsen et al., 1999) and improve biomechanical, biochemical and morphological properties of healing tissue (Gomez et al., 1991). However, as there is no histological evidence of inflammation in tendinosis, this explanation is deficient. It is possible that a purely mechanical explanation of the effects is too simplistic and a neurophysiological explanation is a plausible alternative. 1.1. Aim of the study The aim of this study was to examine the effectiveness of accessory and combined SSTM in the management of a subject diagnosed with Achilles tendinosis. The use of an accessory SSTM in conjunction with a stretch, isometric contraction, active or resisted movement is termed a combined SSTM (Hunter, 1998, 2000). Specifically, the objectives were to determine whether:
Pain, function and muscle length of gastrocnemius and soleus changed in response to a treatment protocol of accessory and then combined SSTM, as the subject progressed. Any changes in signs and symptoms were maintained once the programme stopped up to the 3-month follow-up.
2. Method 2.1. Research design A single case study ABA experimental design was chosen as no clinical trials have investigated the effects of SSTM. It is a useful starting point to establish the need for further research. The complete management of Achilles tendinosis would involve the identification of external and internal causative factors as well as treatment directed towards improving strength and flexibility of the Achilles tendon. However, the single case study allows evaluation of one component of the management in isolation. The Hammersmith and Queen Charlottes’ & Chelsea Hospitals Research Ethics Committee granted ethical approval. 2.2. Subject The main inclusion criterion for the study was Achilles tendon pain for more than 3 months (Alfredson et al., 1998; Silbernagel et al., 2001). The diagnosis was made from a complete history and objective examination. Presence of morning stiffness, pain on loading the tendon during a heel raise, pain on palpation (Galloway et al., 1992; Kvist, 1994), decreased length of soleus or gastrocnemius (Ja¨rvinen et al., 2001) and restricted accessory glide of the tendon (Paavola et al., 2002) were focal points of the diagnosis. A slump and SLR were used to screen for any obvious adverse neurodynamics. Exclusion criteria were: associated LBP, previous foot injury or surgery, evidence or diagnosis of an inflammatory arthropathy, diabetes or any other medical diagnosis that was thought to interfere with the study. A 39-year-old female met the criteria and consented to enter the study. She had a 5-year history of bilateral Achilles pain with no obvious cause. The side with the most severe pain varied but the left had been worse for a year. She had played regular club hockey for 13 years as a goalkeeper, training and playing a game each week. She described soreness over the Achilles tendon for a day after playing hockey and following her walk to work and had used analgesia before games for the last 6 months. She also went to the gym three times a week and had altered her programme to avoid aggravating the pain. Pain occasionally disturbed her sleep. Objectively she had tightness of the left gastrocnemius and soleus. The most comparable stretch biased soleus with weight-bearing dorsiflexion, knee flexion and lateral rotation of the hip. A medial glide of the Achilles tendon was restricted, reproducing the most severe symptoms. Accessory joint movement at the talocrural, subtalar and midtarsal joint was similar on both sides
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suggesting that the limitation to dorsiflexion was from triceps surae.
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et al., 2002) as triceps surae is a limiting factor to dorsiflexion (Palastanga et al., 1993).
2.3. Procedure 2.5. Phase B: treatment The study was divided into three phases and a 3month follow–up. 2.4. Phase A: pre-treatment assessment Baseline measurements were taken of all the dependent variables once a week at the same time each week for 6 weeks. No treatment was given. 2.4.1. Function The VISA A is a valid and reliable index of severity of Achilles tendinopathy (Robinson et al., 2001). It was a useful guide to represent change and a desirable outcome for the subject as it included many of the subjective markers that arose in the patient’s history. A rest period was given to allow for resolution of pain between questions where symptoms were reproduced. Use of equipment and instructions given were standardized when answering questions. 2.4.2. Pain The subject was asked to mark an on a 10 cm line where 0 was no pain and 10 was the worst imaginable pain (Carlsson, 1983; Price et al., 1983). To ensure consistency, the subject was always asked to record her average pain intensity over the 24 h preceding the assessment. 2.4.3. Muscle length For soleus: Dorsiflexion of the foot in weight-bearing was measured by the distance of the great toe from a wall as described by Bennell et al. (1998). The distance was recorded using a tape measure, which was placed face down to minimize observer bias. The mean of three measurements was taken. For gastrocnemius: A goniometer was used to measure the range of dorsiflexion with knee extension. Goniometry has been found to have fair intratester reliability when used to measure ankle range (Elveru et al., 1988). The goniometer was blacked out with tape so that the assessor was unaware of the recording as it was taken. The mean of three measurements was recorded as the use of repeated measures further improved reliability (Youdas et al., 1993). These latter two measurements were taken to reflect a change in triceps surae length as assessed through ankle dorsiflexion. Although this is not a true indication of muscle length, this has been used previously (Singer
Treatment was carried out by the author and involved accessory and combined SSTM based on a treatment protocol outlined by Hunter (2000). Initially a sustained medial accessory SSTM to the left Achilles tendon at its insertion was used with the subject prone and the Achilles tendon in neutral. This was the most comparable direction based on quality, range and reproduction of symptoms. The force was applied perpendicular to the line of the Achilles tendon using the thumbs. The force of the application was governed by the point of marked tissue resistance and onset of mildto-moderate discomfort. The first combined SSTM administered was a medial glide with the Achilles tendon on stretch to R1. This was progressed to an accessory glide with an isometric hold of triceps surae. Finally, the medial glide was applied during dynamic through range loading against theraband with the subject prone. Ethical approval was granted on the basis that the treatment would be altered if the patient was not improving. Objective measures, which were separate from the outcome measures, were therefore taken to guide treatment. The most comparable stretch on the Achilles tendon was used, along with number of calf raises and subsequently number of hops, as the objective markers to determine the response to treatment. The objective markers were only altered as the subject improved. As the response to the SSTM in neutral plateaued the treatment was progressed as described in the treatment table (Table 1). The timing of the progression was related to the subject’s response to the objective markers. The subject was given no home exercises or advice on how to manage her symptoms and was asked to continue activities as usual. She had excluded lower limb exercises that aggravated her symptoms from her gym programme prior to the study. The dependent variables were recorded once a week each week for 6 weeks at the same time as in phase A. When this coincided with treatment, the assessment always preceded the treatment.
2.6. Phase A: post-treatment assessment Measurements were taken of ndent variables once a week at the week for 6 weeks. No treatment the subject was advised to continue usual.
all the depesame time each was given and her activities as
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66 Table 1 Treatment table Week
1–2
3
4
5–6
Treatment given
Accessory SSTM with pt prone and Achilles in neutral
Combined SSTM with Achilles on stretch
Combined SSTM with isometric plantarflexion in plantargrade
Repetitions
30 s, 15 reps (break after each set of 5) Two
30 s, 15 reps (break after each set of 5) Two
30 s, 15 reps (break after each set of 5) One
Combined SSTM with through range plantarflexion against theraband 3 20 (break after each set of 5). One
No treatments each week
VISA-A Questionnaire Percentage Scores for: pre-treatment (A), treatment (B), post-treatment (A) and three month follow-up 120
Percentage scores
100 80 percentage scores + two standard deviation
60
mean - two standard deviation
40 20 0 A1 A2 A3 A4 A5 A6 B1 B2 B3 B4 B5 B6 A7 A8 A9 A10 A11 A12 3 month Assessment period f/u
Fig. 1. VISA-A questionnaire percentage for: pre-treatment (A), treatment (B), post-treatment (A) and the 3-month follow-up.
2.7. Post-treatment follow-up All the dependent variables were reassessed 3 months after the final A phase.
3. Results Line graphs are the traditional way to evaluate single case studies and have been used for analysis of continuous data (Ottenbacher, 1986). The interpretation of the results is through visual inspection and the twostandard deviation band (Nourbakhsh and Ottenbacher, 1994). Although visual interpretation is useful because it is insensitive to weak treatment effects, it is frequently criticized because there are no formal rules to interpret data. The two-standard deviation band was therefore used as an adjunct to the analysis. If two consecutive points fall outside of the two-standard deviation in the
treatment phase, this is recorded as a significant change to the assessment phase. The three phases are represented by A1–6, B1–6, A7–13 and the 3-month followup. The VISA A questionnaire has a percentage as the overall score where a high percentage relates to better function and vice versa. In the pre-treatment assessment, the percentages were relatively static but slightly higher towards the end (Fig. 1). There was a sharp increase between B2 and B3 because the subject was able to exercise without pain (Appendix A, question 8). There was a significant change between the first two phases according to the two-standard deviation band. The score reached a maximum of a 100% by the end of the treatment phase which was maintained until the 3month follow-up. In the visual analogue scale (VAS) there was some variation in the pre-treatment assessment with a considerable drop at A4 (Fig. 2). This did not correlate with changes in the other dependent variables in the
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Visual Analogue Scale For Pain (VAS) for: pre-treatment(A), treatment (B), post-treatment (A) and the 3 month follow-up 10 9 8 7 VAS
6
VAS + two standard deviation mean - two standard deviation
5 4 3 2 1
0 A1 A2 A3 A4 A5 A6 B1 B2 B3 B4 B5 B6 A7 A8 A9 A10 A11 A12 3 month Assessment period f/u Fig. 2. Visual analogue scale for pain (VAS) for: pre-treatment (A), treatment (B), post-treatment (A) and the 3-month follow-up.
Soleus Length For: pre-treatment (A), treatment (B), post-treatment (A) and 3 month follow-up
distance from great toe to wall in cm
7 6 5 4 Soleus length + two standard deviation
3
mean - two standard deviation
2 1 0 A1
A2 A3 A4 A5 A6 B1 B2 B3 B4 B5 B6 A7 A8 A9 A10 A11 A12 3 month Assessment period f/u
Fig. 3. Soleus length for: pre-treatment (A), treatment (B), post-treatment (A) and the 3-month follow-up.
same week. There was a slight decrease in pain rating at the end of the pre-treatment phase. However, there was a significant change in the two-standard deviation across the pre-treatment A and B phase which was maintained until the end of the study. In Fig. 3 the distance for soleus was consistently small in the pre-treatment A phase, in contrast to a large increase between B2 and B3. The increase in distance
was recorded as significant by the two-standard deviation band across the first two phases. Visually, the results for gastrocnemius (Fig. 4) correlate with the measurements taken for soleus (Fig. 3). The angles measured for gastrocnemius were quite consistent in the initial A phase with a marked increase between B1 and B2. A maximum of 101 was reached towards the end of the B phase which was maintained in the final A phase
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Degrees of dorsiflexion with knee extension
Length of gastrocnemius for: pre-treatment (A), treatment (B), post-treatment (A) and 3 month follow-up 105
100
95
90
gastrocnemius length mean - two standard deviation + two standard deviation
85
80 A1 A2 A3 A4 A5 A6 B1 B2 B3 B4 B5 B6 A7 A8 A9 A10 A11 A12 3 month Assessment period f/u
Fig. 4. Length of gastrocnemius for: pre-treatment (A), treatment (B), post-treatment (A) and the 3-month follow-up.
at A7 and A9. This was followed by a slight decrease just before the 3-month follow-up. However, the angle was still far greater than the plus two-standard deviation band.
4. Discussion The results of this study have demonstrated that following a treatment protocol of accessory and combined SSTM this subject, with chronic Achilles tendinosis, had improvements in function, pain and length of gastrocnemius and soleus. These beneficial effects were maintained through the final A phase when no treatment was administered and at the 3-month follow-up. The baseline data collected in the pretreatment A phase did not demonstrate an overall trend of improvement, although there was a slight reduction in pain intensity. This suggests that the considerable improvements during the B phase were due to the intervention rather than a natural variation in symptoms. Spontaneous recovery also seemed unlikely because the condition was chronic and worsening. The subject had not had a period of remission for longer than a week prior to the intervention, and in this study maintained her improvements to the 3-month follow-up. Selection of the ABA rather than ABC design allowed the effects to be narrowed to the intervention without any contribution from home exercises. This was particularly important because of the evidence supporting the use of exercises that load the
Achilles tendon (Alfredson et al., 1998; Silbernagel et al., 2001). There was a possible flaw in question 7 in the VISA A, which asked whether sport or physical activity was being undertaken. No single response was entirely appropriate for this subject. A maximum score was awarded for competing at the same or higher level as when symptoms began. As she was always able to play hockey this response could have been selected. However, her gym routine had been modified as a result of her symptoms which made the second response equally applicable. The author answered the question on the basis of her training to reflect change and only awarded her the maximum score when she started competing at a higher level than before the symptoms began. Even without this question there was a dramatic improvement in the VISA A questionnaire during the B and final A phase. The VAS varied more than the other dependent variables. The substantial decrease in pain recorded in A4 was difficult to explain. Looking at the VISA A questionnaire, it was possible to see that on the same day, the subject recorded a similar level of pain during her walk to work. However, the pain recorded on questions 4 and 5 (Appendix A) did not correspond in the same way. The highest pain in conjunction with the worst score in the VISA A was recorded the week before in A3. The only change of note between A3 and A4 was the subject’s purchase of a new pair of shoes. A major weakness of this study was the lack of an independent observer. However, efforts were made to
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minimize observer bias as detailed in the methods. Another important limitation of any single case study is its lack of control. The design seeks to minimize the likelihood that results are due to spontaneous recovery by taking recordings over a sufficient time period. A placebo effect is possible because of the subject’s faith in the intervention, possibly augmented by her participation in a research project with connotations that she was receiving the best, most up to date treatment. However, her faith and any placebo effect associated with hands on treatment seem insufficient to explain the improvement maintained throughout the post-treatment phase and at 3-month follow-up.
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5. Conclusion The results of this study demonstrated that a treatment protocol of accessory and combined SSTM was followed by an improvement in pain, function and length of gastrocnemius and soleus in a subject with Achilles tendinosis. The chronic nature of the subject’s condition and stable baseline measurements suggest that the improvements were not a result of spontaneous recovery. The single case study design limits generalization, but the results suggest that further research in the form of controlled trials is warranted.
Acknowledgement 4.1. Suggestions for further research The results from this study suggest that further research into SSTM for Achilles tendinosis is warranted. The evidence behind heavy-load eccentric exercises suggests that this should be part of the management of patients with Achilles tendinosis. Therefore, a randomized controlled trial looking at SSTM and heavy-load eccentric exercises would be a useful area for future research.
The author would like to thank Glenn Hunter for his comments on a previous version of the text.
Appendix A The VISA A questionnaire reproduced by kind permission of BMJ publishing group, British Journal of Sports Medicine (2001) 35: 335–341.
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Manual Therapy 12 (2007) 63–71 www.elsevier.com/locate/math
Original article
Effectiveness of specific soft tissue mobilizations for the management of Achilles tendinosis: Single case study—Experimental design Rebecca E. Christenson,1 Pure Sports Medicine, David Lloyd Club, Point West, 116 Cromwell Road, Kensington, London SW7 4XR, UK Received 6 January 2005; received in revised form 22 January 2006; accepted 15 February 2006
Abstract A single case study ABA design was used to evaluate the effectiveness of a treatment protocol of accessory and combined specific soft tissue mobilizations (SSTMs) in a 39-year-old female with a 5-year history of Achilles tendinosis. The study involved three phases each lasting 6 weeks: a pre-treatment, treatment and post-treatment phase. There was also a 3-month follow-up after the post-treatment phase. The VISA A questionnaire was used as a severity index for Achilles tendinosis to quantify symptoms and dysfunction. A visual analogue scale (VAS) was used to record pain. Dorsiflexion range was measured using a goniometer with the knee extended to reflect gastrocnemius length and a weight-bearing dorsiflexion lunge test was used as a measure for soleus length. Following treatment, considerable improvements were recorded in all outcomes. The subject returned to a full gym programme and recorded no pain on the VAS as well as scoring 100% on the index of severity for Achilles tendinosis during the post-treatment phase and follow-up. The single case study design limits generalization but the results support the use of SSTMs in the treatment of Achilles tendinosis and suggests that further research into this intervention is warranted. r 2006 Elsevier Ltd. All rights reserved. Keywords: Achilles tendinosis; Specific soft tissue mobilizations; Single case study
1. Introduction Achilles tendinosis involves pathological changes to the tendon, characterized by an absence of inflammatory cells (A˚stro¨m and Rausing, 1995; Khan et al., 1999). Achilles tendon disorders are common, particularly in sporting individuals but can occur in those with a sedentary lifestyle (Alfredson and Lorentzon, 2000). The history often involves overuse either by a sudden increase in training or sustained high-level training (Kannus, 1997; Almekinders and Temple, 1998). Symptoms are aggravated by activities that load the Achilles tendon, commonly running (McCrory Tel.: +870 2000 878.
E-mail address: [email protected]. Research carried out at: Hammersmith Hospital, DuCane Road, London W12 0HS, UK. 1
1356-689X/$ - see front matter r 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2006.02.012
et al., 1999; Humble and Nugent, 2001; Kader et al., 2002; Paavola et al., 2002). These patients often have pain on and off for many years. Rest can ease the symptoms but is normally insufficient to allow return to the aggravating activity (Kvist, 1994; Maffulli and Kader, 2002). The pathogenesis is not entirely understood but mechanical load placed on the tendon, whether excessive or moderate, seems to result in microtrauma. The tendon then responds poorly with slow or incomplete healing and lacks extracellular organization (Cook et al., 2002). Normal tendon fibres are composed of predominantly type I collagen (Hayem, 2001). Histology of pathologic Achilles tendons have shown a chronic increase in type III collagen as well as disordered fibre arrangement (Ja¨rvinen et al., 1997; Khan et al., 1999; Maffulli et al., 2000; Eriksen et al., 2002). This thinner and less durable collagen compromises the function of the tendon and its ability to withstand load. Adding to
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this picture of mechanical disadvantage are the observations of increased mucoid ground substance, abnormal appearance and activity of tenocytes and neovascularization (A˚stro¨m and Rausing, 1995; Movin et al., 1997; Khan and Maffulli, 1998; Cook et al., 2001). Conservative management remains a challenge because of the deficient tendon repair and incomplete understanding of the pathology. Despite this, there does seem to be reasonable evidence for heavy-load eccentric calf muscle training in the management of Achilles tendinosis (Alfredson et al., 1998). A rational for this is that exercise may be able to affect and improve extracellular organization (Kannus et al., 1997; Wren et al., 2000). Convincing evidence behind manual therapy treatment of acute soft tissue injuries or tendinopathies is scant. However, empirically, the use of mobilizations to produce a mechanical effect has been advocated. Hunter (1994) developed specific soft tissue mobilizations (SSTMs) which tension the soft tissue via accessory soft tissue movement, physiological joint motion or a combination of both techniques. Hunter (1998) proposed a mechanical model to explain the potential effects of SSTM, suggesting that they may increase collagen synthesis and improve collagen alignment. There is evidence that application of a specific force to healing tissue can increase fibroblast activation (Davidson et al., 1997; Gehlsen et al., 1999) and improve biomechanical, biochemical and morphological properties of healing tissue (Gomez et al., 1991). However, as there is no histological evidence of inflammation in tendinosis, this explanation is deficient. It is possible that a purely mechanical explanation of the effects is too simplistic and a neurophysiological explanation is a plausible alternative. 1.1. Aim of the study The aim of this study was to examine the effectiveness of accessory and combined SSTM in the management of a subject diagnosed with Achilles tendinosis. The use of an accessory SSTM in conjunction with a stretch, isometric contraction, active or resisted movement is termed a combined SSTM (Hunter, 1998, 2000). Specifically, the objectives were to determine whether:
Pain, function and muscle length of gastrocnemius and soleus changed in response to a treatment protocol of accessory and then combined SSTM, as the subject progressed. Any changes in signs and symptoms were maintained once the programme stopped up to the 3-month follow-up.
2. Method 2.1. Research design A single case study ABA experimental design was chosen as no clinical trials have investigated the effects of SSTM. It is a useful starting point to establish the need for further research. The complete management of Achilles tendinosis would involve the identification of external and internal causative factors as well as treatment directed towards improving strength and flexibility of the Achilles tendon. However, the single case study allows evaluation of one component of the management in isolation. The Hammersmith and Queen Charlottes’ & Chelsea Hospitals Research Ethics Committee granted ethical approval. 2.2. Subject The main inclusion criterion for the study was Achilles tendon pain for more than 3 months (Alfredson et al., 1998; Silbernagel et al., 2001). The diagnosis was made from a complete history and objective examination. Presence of morning stiffness, pain on loading the tendon during a heel raise, pain on palpation (Galloway et al., 1992; Kvist, 1994), decreased length of soleus or gastrocnemius (Ja¨rvinen et al., 2001) and restricted accessory glide of the tendon (Paavola et al., 2002) were focal points of the diagnosis. A slump and SLR were used to screen for any obvious adverse neurodynamics. Exclusion criteria were: associated LBP, previous foot injury or surgery, evidence or diagnosis of an inflammatory arthropathy, diabetes or any other medical diagnosis that was thought to interfere with the study. A 39-year-old female met the criteria and consented to enter the study. She had a 5-year history of bilateral Achilles pain with no obvious cause. The side with the most severe pain varied but the left had been worse for a year. She had played regular club hockey for 13 years as a goalkeeper, training and playing a game each week. She described soreness over the Achilles tendon for a day after playing hockey and following her walk to work and had used analgesia before games for the last 6 months. She also went to the gym three times a week and had altered her programme to avoid aggravating the pain. Pain occasionally disturbed her sleep. Objectively she had tightness of the left gastrocnemius and soleus. The most comparable stretch biased soleus with weight-bearing dorsiflexion, knee flexion and lateral rotation of the hip. A medial glide of the Achilles tendon was restricted, reproducing the most severe symptoms. Accessory joint movement at the talocrural, subtalar and midtarsal joint was similar on both sides
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suggesting that the limitation to dorsiflexion was from triceps surae.
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et al., 2002) as triceps surae is a limiting factor to dorsiflexion (Palastanga et al., 1993).
2.3. Procedure 2.5. Phase B: treatment The study was divided into three phases and a 3month follow–up. 2.4. Phase A: pre-treatment assessment Baseline measurements were taken of all the dependent variables once a week at the same time each week for 6 weeks. No treatment was given. 2.4.1. Function The VISA A is a valid and reliable index of severity of Achilles tendinopathy (Robinson et al., 2001). It was a useful guide to represent change and a desirable outcome for the subject as it included many of the subjective markers that arose in the patient’s history. A rest period was given to allow for resolution of pain between questions where symptoms were reproduced. Use of equipment and instructions given were standardized when answering questions. 2.4.2. Pain The subject was asked to mark an on a 10 cm line where 0 was no pain and 10 was the worst imaginable pain (Carlsson, 1983; Price et al., 1983). To ensure consistency, the subject was always asked to record her average pain intensity over the 24 h preceding the assessment. 2.4.3. Muscle length For soleus: Dorsiflexion of the foot in weight-bearing was measured by the distance of the great toe from a wall as described by Bennell et al. (1998). The distance was recorded using a tape measure, which was placed face down to minimize observer bias. The mean of three measurements was taken. For gastrocnemius: A goniometer was used to measure the range of dorsiflexion with knee extension. Goniometry has been found to have fair intratester reliability when used to measure ankle range (Elveru et al., 1988). The goniometer was blacked out with tape so that the assessor was unaware of the recording as it was taken. The mean of three measurements was recorded as the use of repeated measures further improved reliability (Youdas et al., 1993). These latter two measurements were taken to reflect a change in triceps surae length as assessed through ankle dorsiflexion. Although this is not a true indication of muscle length, this has been used previously (Singer
Treatment was carried out by the author and involved accessory and combined SSTM based on a treatment protocol outlined by Hunter (2000). Initially a sustained medial accessory SSTM to the left Achilles tendon at its insertion was used with the subject prone and the Achilles tendon in neutral. This was the most comparable direction based on quality, range and reproduction of symptoms. The force was applied perpendicular to the line of the Achilles tendon using the thumbs. The force of the application was governed by the point of marked tissue resistance and onset of mildto-moderate discomfort. The first combined SSTM administered was a medial glide with the Achilles tendon on stretch to R1. This was progressed to an accessory glide with an isometric hold of triceps surae. Finally, the medial glide was applied during dynamic through range loading against theraband with the subject prone. Ethical approval was granted on the basis that the treatment would be altered if the patient was not improving. Objective measures, which were separate from the outcome measures, were therefore taken to guide treatment. The most comparable stretch on the Achilles tendon was used, along with number of calf raises and subsequently number of hops, as the objective markers to determine the response to treatment. The objective markers were only altered as the subject improved. As the response to the SSTM in neutral plateaued the treatment was progressed as described in the treatment table (Table 1). The timing of the progression was related to the subject’s response to the objective markers. The subject was given no home exercises or advice on how to manage her symptoms and was asked to continue activities as usual. She had excluded lower limb exercises that aggravated her symptoms from her gym programme prior to the study. The dependent variables were recorded once a week each week for 6 weeks at the same time as in phase A. When this coincided with treatment, the assessment always preceded the treatment.
2.6. Phase A: post-treatment assessment Measurements were taken of ndent variables once a week at the week for 6 weeks. No treatment the subject was advised to continue usual.
all the depesame time each was given and her activities as
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66 Table 1 Treatment table Week
1–2
3
4
5–6
Treatment given
Accessory SSTM with pt prone and Achilles in neutral
Combined SSTM with Achilles on stretch
Combined SSTM with isometric plantarflexion in plantargrade
Repetitions
30 s, 15 reps (break after each set of 5) Two
30 s, 15 reps (break after each set of 5) Two
30 s, 15 reps (break after each set of 5) One
Combined SSTM with through range plantarflexion against theraband 3 20 (break after each set of 5). One
No treatments each week
VISA-A Questionnaire Percentage Scores for: pre-treatment (A), treatment (B), post-treatment (A) and three month follow-up 120
Percentage scores
100 80 percentage scores + two standard deviation
60
mean - two standard deviation
40 20 0 A1 A2 A3 A4 A5 A6 B1 B2 B3 B4 B5 B6 A7 A8 A9 A10 A11 A12 3 month Assessment period f/u
Fig. 1. VISA-A questionnaire percentage for: pre-treatment (A), treatment (B), post-treatment (A) and the 3-month follow-up.
2.7. Post-treatment follow-up All the dependent variables were reassessed 3 months after the final A phase.
3. Results Line graphs are the traditional way to evaluate single case studies and have been used for analysis of continuous data (Ottenbacher, 1986). The interpretation of the results is through visual inspection and the twostandard deviation band (Nourbakhsh and Ottenbacher, 1994). Although visual interpretation is useful because it is insensitive to weak treatment effects, it is frequently criticized because there are no formal rules to interpret data. The two-standard deviation band was therefore used as an adjunct to the analysis. If two consecutive points fall outside of the two-standard deviation in the
treatment phase, this is recorded as a significant change to the assessment phase. The three phases are represented by A1–6, B1–6, A7–13 and the 3-month followup. The VISA A questionnaire has a percentage as the overall score where a high percentage relates to better function and vice versa. In the pre-treatment assessment, the percentages were relatively static but slightly higher towards the end (Fig. 1). There was a sharp increase between B2 and B3 because the subject was able to exercise without pain (Appendix A, question 8). There was a significant change between the first two phases according to the two-standard deviation band. The score reached a maximum of a 100% by the end of the treatment phase which was maintained until the 3month follow-up. In the visual analogue scale (VAS) there was some variation in the pre-treatment assessment with a considerable drop at A4 (Fig. 2). This did not correlate with changes in the other dependent variables in the
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Visual Analogue Scale For Pain (VAS) for: pre-treatment(A), treatment (B), post-treatment (A) and the 3 month follow-up 10 9 8 7 VAS
6
VAS + two standard deviation mean - two standard deviation
5 4 3 2 1
0 A1 A2 A3 A4 A5 A6 B1 B2 B3 B4 B5 B6 A7 A8 A9 A10 A11 A12 3 month Assessment period f/u Fig. 2. Visual analogue scale for pain (VAS) for: pre-treatment (A), treatment (B), post-treatment (A) and the 3-month follow-up.
Soleus Length For: pre-treatment (A), treatment (B), post-treatment (A) and 3 month follow-up
distance from great toe to wall in cm
7 6 5 4 Soleus length + two standard deviation
3
mean - two standard deviation
2 1 0 A1
A2 A3 A4 A5 A6 B1 B2 B3 B4 B5 B6 A7 A8 A9 A10 A11 A12 3 month Assessment period f/u
Fig. 3. Soleus length for: pre-treatment (A), treatment (B), post-treatment (A) and the 3-month follow-up.
same week. There was a slight decrease in pain rating at the end of the pre-treatment phase. However, there was a significant change in the two-standard deviation across the pre-treatment A and B phase which was maintained until the end of the study. In Fig. 3 the distance for soleus was consistently small in the pre-treatment A phase, in contrast to a large increase between B2 and B3. The increase in distance
was recorded as significant by the two-standard deviation band across the first two phases. Visually, the results for gastrocnemius (Fig. 4) correlate with the measurements taken for soleus (Fig. 3). The angles measured for gastrocnemius were quite consistent in the initial A phase with a marked increase between B1 and B2. A maximum of 101 was reached towards the end of the B phase which was maintained in the final A phase
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Degrees of dorsiflexion with knee extension
Length of gastrocnemius for: pre-treatment (A), treatment (B), post-treatment (A) and 3 month follow-up 105
100
95
90
gastrocnemius length mean - two standard deviation + two standard deviation
85
80 A1 A2 A3 A4 A5 A6 B1 B2 B3 B4 B5 B6 A7 A8 A9 A10 A11 A12 3 month Assessment period f/u
Fig. 4. Length of gastrocnemius for: pre-treatment (A), treatment (B), post-treatment (A) and the 3-month follow-up.
at A7 and A9. This was followed by a slight decrease just before the 3-month follow-up. However, the angle was still far greater than the plus two-standard deviation band.
4. Discussion The results of this study have demonstrated that following a treatment protocol of accessory and combined SSTM this subject, with chronic Achilles tendinosis, had improvements in function, pain and length of gastrocnemius and soleus. These beneficial effects were maintained through the final A phase when no treatment was administered and at the 3-month follow-up. The baseline data collected in the pretreatment A phase did not demonstrate an overall trend of improvement, although there was a slight reduction in pain intensity. This suggests that the considerable improvements during the B phase were due to the intervention rather than a natural variation in symptoms. Spontaneous recovery also seemed unlikely because the condition was chronic and worsening. The subject had not had a period of remission for longer than a week prior to the intervention, and in this study maintained her improvements to the 3-month follow-up. Selection of the ABA rather than ABC design allowed the effects to be narrowed to the intervention without any contribution from home exercises. This was particularly important because of the evidence supporting the use of exercises that load the
Achilles tendon (Alfredson et al., 1998; Silbernagel et al., 2001). There was a possible flaw in question 7 in the VISA A, which asked whether sport or physical activity was being undertaken. No single response was entirely appropriate for this subject. A maximum score was awarded for competing at the same or higher level as when symptoms began. As she was always able to play hockey this response could have been selected. However, her gym routine had been modified as a result of her symptoms which made the second response equally applicable. The author answered the question on the basis of her training to reflect change and only awarded her the maximum score when she started competing at a higher level than before the symptoms began. Even without this question there was a dramatic improvement in the VISA A questionnaire during the B and final A phase. The VAS varied more than the other dependent variables. The substantial decrease in pain recorded in A4 was difficult to explain. Looking at the VISA A questionnaire, it was possible to see that on the same day, the subject recorded a similar level of pain during her walk to work. However, the pain recorded on questions 4 and 5 (Appendix A) did not correspond in the same way. The highest pain in conjunction with the worst score in the VISA A was recorded the week before in A3. The only change of note between A3 and A4 was the subject’s purchase of a new pair of shoes. A major weakness of this study was the lack of an independent observer. However, efforts were made to
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minimize observer bias as detailed in the methods. Another important limitation of any single case study is its lack of control. The design seeks to minimize the likelihood that results are due to spontaneous recovery by taking recordings over a sufficient time period. A placebo effect is possible because of the subject’s faith in the intervention, possibly augmented by her participation in a research project with connotations that she was receiving the best, most up to date treatment. However, her faith and any placebo effect associated with hands on treatment seem insufficient to explain the improvement maintained throughout the post-treatment phase and at 3-month follow-up.
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5. Conclusion The results of this study demonstrated that a treatment protocol of accessory and combined SSTM was followed by an improvement in pain, function and length of gastrocnemius and soleus in a subject with Achilles tendinosis. The chronic nature of the subject’s condition and stable baseline measurements suggest that the improvements were not a result of spontaneous recovery. The single case study design limits generalization, but the results suggest that further research in the form of controlled trials is warranted.
Acknowledgement 4.1. Suggestions for further research The results from this study suggest that further research into SSTM for Achilles tendinosis is warranted. The evidence behind heavy-load eccentric exercises suggests that this should be part of the management of patients with Achilles tendinosis. Therefore, a randomized controlled trial looking at SSTM and heavy-load eccentric exercises would be a useful area for future research.
The author would like to thank Glenn Hunter for his comments on a previous version of the text.
Appendix A The VISA A questionnaire reproduced by kind permission of BMJ publishing group, British Journal of Sports Medicine (2001) 35: 335–341.
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