Predictors of Functional Outcomes following Operative Treatment of Acute Achilles Tendon Ruptures

CATEGORY: Trauma; Ankle; Hindfoot INTRODUCTION/PURPOSE: Previous studies involving operative and nonoperative management of Achilles tendon ruptures have attempted to determine if patient factors influence treatment outcomes, with female sex, older age, and greater body mass index associated with inferior results. However, to our knowledge, no previous study has attempted to identify predictors of functional outcomes in patients exclusively undergoing surgical repair of acute Achilles tendon ruptures. The purpose of this study is to determine if any injury or patient variables were predictive of functional outcomes following operative management of acute Achilles tendon ruptures. METHODS: A retrospective review of patients undergoing primary open repair of acute Achilles tendon ruptures with a single fellowship-trained orthopaedic foot & ankle surgeon at a single surgical location from 2010-2016 was performed. Patients <18 years of age, those who underwent surgical repair >21 days from the date of injury, and those whose repair required a V-Y advancement were excluded. Patient demographics (age, sex, BMI), comorbidities (diabetes mellitus, depression, anxiety), mechanism of injury (sports versus non-sports), and date of injury were collected. Postoperative chart notes were reviewed to document patient noncompliance. Included patients >=2 years removed from surgery were contacted to complete the Foot & Ankle Ability Measure (FAAM)-Activities of Daily Living (ADL) and -Sports subscales, and visual analog scale (VAS) for pain. Multivariable regression analysis was performed to determine significant independent predictors of functional outcomes. Regression coefficients with 95% confidence intervals [95% CI] and p-values were reported for significant findings. RESULTS: Of the 195 Achilles tendon repairs meeting the inclusion criteria, 140 (71.8%) were contacted to complete 2-year follow-up and analyzed. No patients (0%) experienced tendon re-ruptures. On multivariable analysis, female sex was independently associated with lower FAAM-Sports score (-10.11 [-19.73, -0.50]) and a lower Single Assessment Numeric Evaluation (SANE) score from the FAAM-Sports subscale (-13.79 [-26.28, -1.30]; p=0.0325). A history of anxiety was related to a lower FAAM-ADL score (-29.02 [-45.68, -12.36]; p=0.0009), FAAM-Sports score (-33.41 [-64.46, -2.37]; p=0.0368), and a higher VAS pain score (19.83 [4.43, 35.23]; p=0.0128). Age, BMI, a history of depression or diabetes mellitus, mechanism of injury, timing of repair, and patient compliance were not independently predictive of functional outcomes. CONCLUSION: Females and patients with anxiety have significantly poorer functional outcomes following acute Achilles tendon repair. To our knowledge, this is the first study to investigate and identify variables predictive of patient functionality in a population of surgically managed acute Achilles tendon ruptures. Further study is indicated to determine whether these factors are also predictive of outcomes of Achilles tendon ruptures treated non-surgically, and how this may affect surgical indications in this patient population.