Functional and MRI follow-up after reconstruction of chronic ruptures of the Achilles tendon Myerson type III using the triple-loop plantaris tendon wrapped with central turndown flap: a case series

BACKGROUND: Reconstruction of chronic ruptures of the Achilles tendon poses a great challenge for the orthopaedic surgeon both technically and functionally. The aim of this study was to assess the results of a new technique for reconstruction of chronic Achilles tendon ruptures with defects longer than 5 cm using the triple-loop plantaris tendon autograft wrapped in a central turndown flap from the proximal portion of the Achilles tendon. PATIENTS AND METHODS: Eighteen patients (14 female and 4 male; mean age, 40.7 years), having chronic ruptures of the Achilles tendon Myerson type III, were enrolled in this study. The mean follow-up period of our patients was 21.8 months. All patients were assessed via the following parameters: lag of interference since the first complaint, length of the defect, length of the turndown flap and length of the harvested plantaris tendon, surgery time, complications, active range of motion at the ankle and the final score. Average values were presented as means. Independent sample t test, Mann Whitney test, paired sample t test and Pearson’s correlation coefficient were used to evaluate the clinical and functional results. The results were considered statistically significant if a P value was <0.05. To analyse the time course of the gap following surgery, the data from the first MRI session were compared with those from the second and third sessions using the Wilcoxon’s signed rank test. In addition, the paired data of the tendon gap disappearance rate between T1-weighted and T2-weighted images were also compared using the McNemar test. RESULTS: The mean preoperative American Orthopaedic Foot and Ankle Society score was 62.2 points while at the patients’ last follow-up, the mean postoperative score was 94.9 points. The results of this study confirmed that both the Achilles tendon healing and tendon gap disappearance have been perceived with higher sensitivity in T2-weighted images than in T1-weighted images. CONCLUSIONS: We believe that this new technique is biologic, synchronous and reliable in cases of chronic Achilles tendon ruptures with defects longer than 5 cm.