A Randomized Controlled Trial Comparing Traditional Plaster Cast Rehabilitation with Functional Walking Boot Rehabilitation for Acute Achilles Tendon Ruptures

SLR - November 2020 - Christopher M. Gill

Reference: Maempel JF, Clement ND, Duckworth AD, Keenan OJF, White TO, Biant LC. A Randomized Controlled Trial Comparing Traditional Plaster Cast Rehabilitation with Functional Walking Boot Rehabilitation for Acute Achilles Tendon Ruptures. Am J Sports Med. 2020 Sep;48(11):2755-2764. 

Level of Evidence: Level 2

Scientific Literature Review

Reviewed By: Christopher M. Gill, DPM
Residency Program: Central Michigan University Medical Education Partners – Saginaw, MI

Podiatric Relevance: Conservative treatment plays an important role in the decision making for foot and ankle surgeons in the care of acute Achilles tendon ruptures. Conservative treatment usually involves rehabilitation with a period of non-weightbearing in a plaster cast. However, there has been a recent change in thought regarding the traditional method of cast immobilization rehabilitation. Functional non-operative rehabilitation in a walking boot with immediate weightbearing has become increasingly popular, although there appears to be a paucity of literature comparing the two conservative treatment methods. This study examined patients who experienced acute Achilles tendon ruptures and were treated using either a traditional plaster cast or walking boot.

Methods: A level two randomized control trial was used to study patients who suffered an acute Achilles tendon rupture using either non-operative rehabilitation with cast immobilization or weightbearing in a walking boot. A total of 140 patients were randomized into either traditional rehabilitation in a plaster cast (71 patients) or functional rehabilitation in a walking boot (69 patients). Immobilization with a cast involved reducing degrees of equinus over 10 weeks with eight weeks of non-weightbearing. The functional rehabilitation group was allowed to immediately bear weight with a walking boot and decreased heel wedge intervals over eight weeks. The primary outcome measure was compared using the Short Musculoskeletal Functional Assessment (SMFA). The authors also looked at the Achilles Tendon Total Rupture Score (ATRS), the Foot and Ankle Questionnaire, incidence of DVT, tendon re-rupture, driving, return to work, calf circumference, ankle range of motion and pain. 

Results: Results showed higher SMFA, ATRS and Foot and Ankle Questionnaire scores in the group treated with a walking boot at the six-month follow-up. However, both groups showed similar improvements after one year, with no significant difference between the two groups. Achilles tendon re-rupture and incidence of DVT were slightly higher in the plaster cast group, however this was not considered statistically significant. Skin breakdown was noted in 15 patients who received the walking boot, with no skin issues noted in the plaster cast group. Patients in the walking boot started driving one week earlier, with no difference in return to work time. Calf circumference was noted to be decreased in both groups compared to the contralateral calf. No significant difference in range of motion or pain was noted at the final follow-up between the two groups.

Conclusions: Functional rehabilitation with immediate weightbearing is an excellent and safe alternative to the traditional conservative treatment of plaster casting. The walking boot group showed a noted improvement in short-term outcomes compared to the cast immobilization group, however both groups showed an equal amount of improvement after one year. Although not considered statistically significant, the re-rupture rate of the traditional plaster cast group was more than double that of the walking boot group. The walking boot group was associated with more skin problems, however all skin issues resolved with no complications. Additional studies to investigate re-rupture rates between the two groups would be recommended, as a difference between the two was noted.