The Ruptured Achilles Tendon Elongates for Six Months After Surgical Repair Regardless of Early or Late Weightbearing in Combination with Ankle Mobilization: A Randomized Clinical Trial

SLR - September 2018 - Dana M. Berns

Reference: Eliasson P, Agergaard AS, Couppé C, Svensson R, Hoeffner R, Warming S, Warming N, Holm C, Jensen MH, Krogsgaard M, Kjaer M, Magnusson SP. The Ruptured Achilles Tendon Elongates for Six Months After Surgical Repair Regardless of Early or Late Weightbearing in Combination with Ankle Mobilization: A Randomized Clinical Trial. Am J Sports Med. 2018 Jun;1:363546518781826.

Scientific Literature Review

Reviewed By: Dana M. Berns, DPM
Residency Program: Mercy Hospital and Medical Center, Chicago, IL

Podiatric Relevance: Treatment strategies for Achilles tendon rupture is heavily debated in the literature. The magnitude of tendon elongation affects clinical outcomes. The objective of this study was to evaluate if tendon elongation, mechanical properties and functional outcomes during the recuperation of surgically repaired acute Achilles tendon ruptures were influenced by various rehabilitation treatments during the early postoperative period. The authors hypothesized that restricted early weightbearing with limited motion at the ankle in the initial phase of tendon healing will limit tendon elongation and improve functional outcomes.

Methods: A level I randomized controlled trial was performed on 75 patients with an acute Achilles tendon midsubstance rupture. After surgical repair, four tantalum metal beads (diameter of 1.0 mm) were implanted with a cannula in the distal and proximal ends of the tendon rupture site. The patients were randomized into three groups: completely nonweightbearing until week seven with full weightbearing allowed after week eight; completely nonweightbearing until week seven with allotted ankle joint mobilization exercises and weightbearing allowed only after week eight; and partial weightbearing from day one with full weightbearing allowed after week five. All groups received identical in-home exercise guidelines starting from week nine. Two-dimensional radiographs were obtained at weeks two, six, 12, 26 and 52, which were used to measure the distance between the tantalum beads as an amount of tendon elongation. Furthermore, tendon and muscle cross-sectional area using MRI, tendon strain measured in loads of 0, 200 and 1200 N, patient-reported outcomes and functional evaluation were all recorded.

Results: No significant effect was found with tendon elongation, yet a significant main effect of time was noted. Elongation increased from six to 12 weeks and from 12 to 26 weeks but not from 26 to 52 weeks. For strain, no significant interaction was found, but a significant main effect of time was noted; strain decreased from six to 26 weeks but not from 26 to 52 weeks. Tendon cross-sectional area was increased from six to 26 weeks and decreased from 26 to 52 weeks. The time to return to work and sporting activity was not significantly different among groups. The early rehabilitation regimen did not significantly influence any of the measured outcomes as well. Muscle strength, muscle endurance and patient-reported functional scores did not reach normal values at 52 weeks. Seven out of 75 patients experienced complications: two reruptures (due to missed steps/falls seven weeks after repair), one adhesion, one DVT and four skin infections.

Conclusions: Achilles tendon elongation was found to be significant and continued for up to 26 weeks after surgery and the time to full function recovery after an Achilles tendon rupture requires at least one year. In the initial eight weeks after surgery, the different loading patterns during restoration of the tendon did not significantly alter outcome parameters. Increased tendon elongation and stiffness may continue for at least six months after surgery; therefore, the surgeon must be aware that rehabilitation may be important beyond the initial two to three months postoperatively.