Comparison of MRI and Operative Findings in Peroneal Tendon Disorders in a Military Population

Abstract

Category: Sports Introduction/Purpose: Peroneal tendon pathology is an overlooked cause of lateral ankle pain and a significant amount of patients are misdiagnosed at their initial visit. Previous studies have compared the magnetic resonance imaging (MRI) findings of peroneal tendon disorders to intraoperative findings with mixed results. The purpose of this study was to compare MRI findings of peroneal tendon pathology to intraoperative findings in an active duty military population. Methods: Active duty military servicemembers who underwent peroneal tendon exploration between 2009-2014 with a preoperative MRI were retrospectively reviewed. Studies were reviewed by a board certified radiologist who was blinded to the purpose of the study. MRI findings were then compared to surgical findings from operative reports. The following peroneal tendon pathologies were identified: peroneus brevis tears, peroneus longus tears, tendinopathy of either tendon, tenosynovitis, presence of peroneus brevis low lying muscle belly or peroneus quartus muscle and injury to the superior peroneal retinaculum. Concomitant procedures such as lateral ankle reconstruction, ankle arthroscopy, or osteotomies were also recorded. Comparative statistics were performed to correlate imaging and surgical findings. Results: Of 32 patients included, peroneus brevis and longus tears were the most common MRI finding while peroneus brevis tears and tenosynovitis were the most common surgical finding. Peroneus longus tears were found in 4 patients during surgery but seen in 12 patients on MRI. The sensitivity/specificity of MRI for peroneus brevis tears were 69% and 74% compared to 75% and 68% for peroneus longus tears. Tenosynovitis had a sensitivity of 9% and specificity of 95%. Twenty two patients (69%) had a low lying peroneus brevis muscle belly with 9 of those patients having a peroneus brevis tear. Of the 7 patients with peroneus quartus muscles identified in surgery, only 1 was seen on MRI and three had a tear of the peroneus brevis. Conclusion: In this study of active duty military personnel, we found similar results to previous published studies. MRI had a slightly lower sensitivity and specificity for diagnosing peroneus brevis tears while being slightly better for peroneus longus tears compared to previously published studies. We found significantly higher percentage of patients with a low lying peroneus brevis muscle belly than previous reported, with a 40% correlation to peroneus brevis tears. In patients with an identified low lying peroneus brevis or peroneus quartus on preoperative imaging, we recommend evaluation for associated tendon tears in active duty military servicemembers presenting with lateral ankle pain.