Demographic Factors Associated with Insertional and Noninsertional Achilles Tendinopathy

Abstract

Category: Sports Introduction/Purpose: Achilles tendinopathy is a common clinical entity encountered by orthopaedic surgeons, although the demographics of patients that suffer from this pathology are incompletely understood. It has been suggested that there may be differences in patients that get insertional (IAT) and noninsertional Achilles tendinopathy (NIAT), and our clinical experience has been that older, less active patients tend to get insertional tendinopathy. The goal of this study is to further investigate the features of patients in a single institution who presented with Achilles tendinopathy. Methods: We used ICD-9 and ICD-10 codes to find patients who presented with Achilles tendinopathy to two foot and ankle surgeons at one academic medical center from 2007-2018. We made note of patient characteristics such as age, gender, BMI, medical comorbidities, and level of activity. Physical examination, including the presence of a gastrocnemius equinus, was noted as well. Characteristics of insertional and non-insertional tendinopathy subgroups were compared using Student’s T-tests and chi- squared tests. Results: The characteristics of 948 consecutive patients were analyzed. The mean age was 55 years and 50.5% of the patients were male. Patients with IAT had significantly higher BMIs than did those with NIAT (30.5 compared to 28.0, p .05). Patients with NIAT self-identified as active a greater percentage of the time (63% vs 45%, p<0.5). 76% of the IAT group had a gastrocnemius equinus on physical examination, compared to 67% of the non-insertional group. Antecedent fluoroquinolone antibiotic use was only reported in 10% of patients, and all of these patients presented with NIAT. Conclusion: The age at which patients present with insertional and noninsertional Achilles tendinopathy is not significantly different, although patients with NIAT had a lower BMI and self-identified as active a greater percentage of the time. A gastrocnemius equinus was present in a high percentage of patients with both IAT and NIAT. Fluoroquinolone use was not involved in most cases, although, when it was, patients presented with NIAT.