Evaluating the Progress of Mid-Portion Achilles Tendinopathy During Rehabilitation: A Review of Outcome Measures for Self- Reported Pain and Function

Abstract

Introduction: Management of mid-portion Achilles tendinopathy is a challenge for both clinicians and researchers. Alteration in tendon structure, muscle performance and pain processing mechanisms have been suggested as mechanisms driving improvement in pain and function. However, few trials have used consistent outcome measures to track changes in pain and function. Objectives: 1) To identify all outcomes measures used in trials utilizing exercise-based interventions for mid-portion Achilles tendinopathy (AT) that assess self-reported pain and function and to report on the reliability and validity of the identified measures, and 2) Propose measures to optimally assess self-reported pain and function in patients with AT. Design: Literature Review Data Sources: Three major electronic databases were searched from inception until May 2016 for studies using isometric, eccentric or isotonic loading protocols for mid-portion AT. Eligibility Criteria: Randomized and non-randomized trials of isometric, eccentric or isotonic loading in people with mid-portion AT. Results: Forty-six studies were included and all outcome measures assessing self-reported pain and function were extracted. While a variety of outcome measures have been used, few have provided reliability data. There is evidence to suggest that the Victorian Institute of Sports Assessment-Achilles (VISA-A) is the only valid and reliable measure of self-reported pain and function for people with mid-portion AT. No other outcome measures have been validated in mid-portion AT. Conclusion: The VISA-A remains the gold standard for assessing pain and function in mid-portion AT. However, while the validity or reliability of the Numerical Rating Scale (NRS) of pain during a functional task has not been established it may be a better measure of immediate treatment effect.

Comparative Efficacy and Tolerability of Nonsurgical Therapies for the Treatment of Midportion Achilles Tendinopathy: A Systematic Review With Network Meta-analysis

“…Currently, the VISA-A is the only valid ( P < .01) and reliable (test-retest reliability, r = 0.98) measure to assess pain and function in AT. 43 , 52 Studies that used the American Orthopaedic Foot and Ankle Score were excluded because it was not designed specifically for AT. 43 Studies that used the visual analog scale (VAS) or numerical rating scale for pain without also using the VISA-A were excluded because the VAS has been shown to have poor test reliability at rest in AT ( r = 0.45).…”

“… 43 , 52 Studies that used the American Orthopaedic Foot and Ankle Score were excluded because it was not designed specifically for AT. 43 Studies that used the visual analog scale (VAS) or numerical rating scale for pain without also using the VISA-A were excluded because the VAS has been shown to have poor test reliability at rest in AT ( r = 0.45). 43 Moreover, the relationship between pain and function is intertwined in tendinopathy since symptoms are load-dependent, and thus including a measure of pain without linking it to function may lead to imprecise estimate of the effect.…”

Intramuscular stimulation vs sham needling for the treatment of chronic midportion Achilles tendinopathy: A randomized controlled clinical trial

“…There were no changes to outcome measures after registration of the protocol at ISCRTN, although we did alter the ultrasound analysis from what was described in our ethics protocol by focusing on tendon thickness rather than echo texture. The primary outcome for which the study was powered was the change from baseline in 12 week VISA-A (Victorian Institute of Sports Assessment-Achilles), a valid and reliable disease-specific outcome measure [37] which also includes an activity-related pain scale. The VISA-A score was also measured at 6, 26 and 52 weeks.…”

“…We assumed that the change in VISA-A from 0 to 12 weeks with exercise alone would be 20 points [37], with a normal distribution and a standard deviation of 12 [23]. We assumed the minimum clinically important difference in VISA-A score to be 12 points [37].…”

“…We assumed that the change in VISA-A from 0 to 12 weeks with exercise alone would be 20 points [37], with a normal distribution and a standard deviation of 12 [23]. We assumed the minimum clinically important difference in VISA-A score to be 12 points [37]. Given these assumptions, to answer the primary question, the trial was powered (at 0.80, with alpha of 0.05) to detect a difference of 12 points between the G3 (IMS) and G2 (sham needling) groups, which for an independent t-test would require a sample size of 16 in each group.…”