Macroscopic Anomalies and Pathological Findings in and Around the Achilles Tendon: Observations From 1661 Operations During a 40-Year Period

BACKGROUND: Nonsurgical treatments for chronic Achilles tendinopathy (AT) results in unpredictable success rates. Surgical treatment may be chosen as reports show mostly encouraging but variable success rates depending on the pathology. The distribution of surgically confirmed pathologies in AT is largely unknown. PURPOSE: To ascertain the distributions of macroscopically observed anomalies in participants undergoing surgical treatment for chronic AT. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: The main macroscopic pathologies of 1661 chronic Achilles tendon overuse injuries, which were diagnosed and surgically treated by a single surgeon, were reviewed. The surgeries were performed on professional and recreational athletes during the years 1976-1980, 1986-1990, 1996-2000, and 2006-2010. Surgical diagnoses, along with age- and sport-specific characteristics, were collected retrospectively from patient records. RESULTS: The relative proportion of tendinosis increased during the study period from 4.2% to 21%, and paratenonitis decreased from 50% to 26%. Retrocalcaneal pathologies were the most common surgically confirmed lesions at 30%, while the mean age at surgery increased by 11 years over the entire study period. CONCLUSION: Surgically confirmed pathologies in and around the Achilles tendon showed coherent changes, chronic paratenonitis, and retrocalcaneal problems as the most prevalent findings. The classification of midportion and insertional tendinopathy and retrocalcaneal bursitis in AT should strictly be used as a clinical diagnosis. During surgical evaluations, the diagnosis is further clarified as more specific pathologies may be identified.