Ultrasonographic Finding of Contralateral Achilles Tendon in Patients With Acute Achilles Tendon Rupture: A Prospective Observational Study

OBJECTIVE: Although the incidence of contralateral Achilles tendon in patients with Achilles tendon rupture is higher than in the general population, there are no studies evaluating the status of the contralateral Achilles tendon. The aim of this study was to investigate the status of the contralateral Achilles tendon in patients with acute Achilles tendon rupture. DESIGN: Prospective observational cohort study. SETTING: University hospital foot and ankle clinic. PARTICIPANTS: Seventy-five patients with acute Achilles tendon rupture who met the inclusion criteria. INTERVENTION: Ultrasonography performed by an orthopedic surgeon who had 8 years of experience in musculoskeletal ultrasonography. MAIN OUTCOME MEASURES: Ultrasonographic abnormalities of the contralateral Achilles tendon at the time of diagnosis of acute Achilles tendon rupture. Abnormalities were categorized as intratendinous lesions, peritendinous lesions, changes in retrocalcaneal bursa, and Achilles tendon thickening. RESULTS: The maximal Achilles tendon thickness had a mean of 4.8 ± 1.0 mm. Nine patients (12%) showed ultrasonographic abnormalities on the contralateral Achilles tendon, and the presence of exertional pain was the sole associating variable with ultrasonographic abnormalities. CONCLUSION: The prevalence of ultrasonographic abnormalities in the contralateral Achilles tendon shown in this study was not higher than that reported in healthy or asymptomatic Achilles tendon. Therefore, routine evaluation of the contralateral Achilles tendon is unnecessary at the time of acute Achilles tendon rupture.