Prospective randomized clinical trial of open operative, minimally invasive and conservative treatments of acute Achilles tendon tear

Abstract

Introduction: The acute Achilles tendon rupture (AATR) is a common injury of great importance in an increasingly active society. When early functional treatment is established, recent literature shows comparable rates of re-rupture in conservative and surgical treatments of AATR. However, there is no study comparing the outcome using a dynamometer. The aim of this study is to evaluate the results of patients with AATR treated conservatively and surgically using a dynamometer. In addition, the data are compared to evaluation of the Achilles tendon with ultrasound.

Materials and methods: Between 2012 and 2015, 90 patients (mean age 41 years, male-to-female ratio 81:9) with AATR were enrolled in a prospective, randomized, and monocentric study. Thirty patients were assigned to each of the three different treatment groups. Group OPEN received a conventional open suture of the Achilles tendon, group MIN received a minimally invasive suture and patients in group CONS were treated conservatively. Follow-up treatment was the same for all patients regardless of the group they were assigned to. Plantar flexion force was assessed using a dynamometer (Biodex® System 3 Pro, Biodex Medical Systems). Further evaluation included a physical test and ultrasound of the Achilles tendon.

Results: Sixty-nine patients were available for a 24-month follow-up. In each of the OPEN and MIN groups, there was one re-rupture. In the CONS group, there were two re-ruptures. A positive correlation between the Biodex® dynamometer measurement and the American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Score (AOFAS-AH) could be found in all groups. Nevertheless, there were no significant differences between the treatment groups after 2 years. On sonography, all patients showed isolated structure loosening and a significantly thickened cross-sectional area compared with the non-injured opposite side, without differences between the groups. There was no correlation between the Biodex® measurement and sonographic outcome.

Conclusion: At 24-month follow-up, no significant difference can be found in patients with AATR treated operatively or conservatively. It is, therefore, important to inform patients with AATR regarding the respective advantages and disadvantages of the individual treatment strategies.

Level of evidence: Randomized controlled trial; level 1.

Keywords: Acute achilles tendon rupture; Dynamometer; Isokinetic force measurement; Minimally invasive surgery; Re-rupture.