SLR - April 2015 - Michael Matthews

Isolated Gastrocnemius Recession for Achilles Tendinopathy: Strength and Functional Outcomes

Reference: Nawoczenski DA, Barske H, Tome J, Dawson LK, Zlotnicki JP, DiGiovanni BF. Isolated Gastrocnemius Recession for Achilles Tendinopathy: Strength and Functional Outcomes. J Bone Joint Surg Am. 2015 Jan 21;97(2):99-105.

Scientific Literature Review

Reviewed By: Michael Matthews, DPM
Residency Program: Mount Auburn Hospital

Podiatric Relevance: The presence of a gastrocnemius contracture manifesting in equinus is a fundamental tenant of lower extremity pathology. A literature review of gastrosoleal equinus related pathology will appreciate that equinus has been thought to be the primary pathological culprit to a very diverse set of lower extremity ailments. These include Achilles tendinopathy, plantar fasciitis, midfoot arthritis, acquired pes planovalgus, hallux abductovalgus, and many others commonly seen podiatric pathology. Conservative care for the issue often requires strict patient compliance to lifestyle modification, stretching, constant physical therapy, and modalities such as the Alfredson protocol. Compliance with the aforementioned regimens is often difficult for patients, which results in subsequent failure of conservative treatment and patient frustration. Over the past decade surgical correction of equinus has become more in vogue, with extratendinous procedures such as the endoscopic gastrocnemius recession (EGR) and Strayer procedure becoming more favored. The presented article examines the outcome measures after the Strayer procedure for chronic Achilles tendinopathy.

Methods: A level III retrospective cohort study was conducted to examine the patient reported outcomes of the use of the Strayer procedure for unilateral Achilles tendinopathy. A retrospective chart review was conducted of all the patients who underwent gastrocnemius recession procedures at a single facility from 2008-2010. Subsequently a sample size of 13 was produced, which was cased matched with 10 controls based on age and BMI. The primary outcome for the study was on the visual analog scale (VAS) and the Foot and Ankle Ability Measure (FAAM). The secondary outcome was strength testing, specifically measuring plantarflexion strength at 60 degrees/sec and 120 degrees/sec. Inclusion criteria were (1) isolated gastronemius contracture diagnosed via a positive Silfverskiöld test, (2) diagnosis of unilateral insertional or midsubstance tendinopathy on physical exam, (3) a minimum of six months failed conservative therapy, and (4) no concomitant procedures. Exclusion criteria included history of prior surgery on ipsilateral/contralateral Achilles tendon or plantar fascia, spastic contracture due to underlying neurologic process, or previous ankle surgery. Patients were evaluated at an average of 18 months follow up on the VAS scale, the FAAM measure, and the Limb Symmetry Index which evaluated strength testing. One or more of the senior authors received payments from a third party in support of their research, and the study was funded in part by a grant from the American Orthopaedic Foot and Ankle society. Paired t tests were used to compare data between the subject and control groups, and a p value of less than 0.05 was established for statistical significance.     

Results: A total of 13 patients met the inclusion criteria, which consisted of 10 subjects with insertional Achilles tendinopathy, and three with midsubstance pathology. These were matched against 10 controls by age and BMI. Recession of the gastrocnemius provided a statistically significant relief of pain.  FAAM analysis showed the surgical cohort scored an average of 89.7 versus 98.5 for the control group.  This is near the 95 percent confidence interval and was considered to be significant for the procedure to allow patients function better with daily activities. FAAM analysis showed a mean score of 71.9 for the surgical group versus 95.1 for the controls when it came to athletic activity, suggesting that the procedure might not be best suited in a highly athletic population. Strength comparisons between the two groups showed no difference at 60 degrees/sec, however showed a significant difference by ways of strength deficit in the Achilles group at 120 degrees/sec. This difference in strength correlated with the poorer performance of the intervention group when it came to athletic activity, a measure that the 120 degrees/sec test was meant to represent.             

Conclusions: The results of the study support the use of a gastrocnemius recession for symptomatic and functional treatment of chronic Achilles tendinopathy. The data suggests that such surgical intervention would better benefit a more average or sedentary individual, and not necessary be a treatment geared towards a highly athletic population. These conclusions are based off of similar FAAM and strength scores for baseline activities of daily living, and also on the large discrepancies between the two groups in the setting of more physically challenging activity. The presented study had several limitations. The first would be a small sample size. Another weakness of the study was that baseline athletic function of the intervention group was not recorded, and therefore it is impossible to determine a comparison between their post and preoperative athletic function. In the future it would be enlightening to see a study examining the pre and post operative effects of an EGR or Strayer in an athletic population. It is unclear whether the open technique of the Strayer recession versus the endoscopic technique now preferred by many in the podiatric profession would have had a difference on patient outcome. It seems likely that satisfaction with the post operative period would be higher with the less invasive technique, but seeing as how the surgical correction with each technique is theoretically the same in terms of result the long term functional outcomes would most likely be quite comparable.  

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