Outcomes of Percutaneous Zadek Osteotomy for Insertional Achilles Tendinopathy with Two-Year Minimum Follow-Up: A Retrospective Study

Introduction/Purpose: Insertional Achilles tendinopathy (IAT) is a common source of posterior heel pain treated by orthopaedic foot and ankle surgeons. Traditional surgical treatment consists of an open Achilles tendon debridement with re-attachment as well as excision of the posterosuperior calcaneal prominence with or without a gastrocnemius recession. However, frequent complications include wound healing issue, scar pain, weakness and sural nerve injury. Accordingly, the percutaneous ZO is gaining popularity in the field as an alternative to an open midline splitting approach. Limited literature exists describing outcomes of the percutaneous ZO using a larger sample size. The purpose of this study was to analyze patient reported outcomes and complications after percutaneous ZO with a minimum two-year follow-up period. Methods: One hundred and eight cases treated with percutaneous ZO were retrospectively reviewed across October 2017-July 2021 and outcomes data was available for 104 cases with a minimum two-year follow-up. Patient sex, age, and pertinent comorbidities were recorded. Postoperative complications and patient satisfaction following intervention were evaluated. Foot Function Index score (FFI) was utilized to measure patients’ pain and functional outcomes. Visual Analyzing Scale score (VAS) was also utilized to evaluate pain. These measurements were taken at preoperative and final follow-up. Statistical comparisons were performed using two-tailed, paired t-test with p< 0.05. Results: Mean follow-up time was 41.2±13.1 months (range 24-65 months). The mean FFI score improved from 56.1±5.9 (range 47-88) preoperatively to 11.0±5.1 (range 7-59) postoperatively (p < 0.001). Average VAS score improved in patients receiving percutaneous ZO from 7.6±1.3 (range 5-10) to 0.4±0.9 (range 0-7) postoperatively (p < 0.001). The overall complication rate was 3.8% (N =4). Of 104 cases, 98.1% of patients were satisfied with their procedure (102/104). Conclusion: The percutaneous ZO is a safe and highly effective intervention for treatment of IAT. At a minimum of two-years follow-up, this intervention is associated with minimal complications, improved functional outcomes, reduced pain, and high patient satisfaction. Table 1 Functional and subjective pain preoperative and postoperative scores as evaluated by functional foot index (FFI) and visual analogue scale (VAS), respectively