Examining the Relationship Between Pathologies of the Peroneal, Achilles, and Posterior Tibial Tendons: An MRI Review in an Asymptomatic Lateral Ankle Population.

The hindfoot and ankle are dynamic structures to which the interplay of tendinous pathologies is scarcely understood. Five hundred consecutive ankle magnetic resonance imaging examinations, obtained between December 27, 2011 and April 9, 2013, were reviewed. Patients without a history of hindfoot or ankle trauma or lateral ankle pain were included. The 108 MRIs that met the inclusion and exclusion criteria were then re-evaluated by 2 musculoskeletal radiologists. Of these, 55.56% demonstrated pathology of the Achilles tendon (AT), 44.44% demonstrated pathology of the posterior tibial tendon (PTT), 35.19% demonstrated pathology of the peroneus brevis (PB), and 37.96% demonstrated pathology of the peroneus longus (PL). In our asymptomatic patient population, 16 (14.81%) patients demonstrated concomitant pathology of the AT, PTT, and peroneal tendons. There were positive, moderate correlations between graded pathology of the AT and the PTT, rs(106) = 0.32, P = .001; the AT and PB, rs(106) = 0.38, P = 0.001; and the AT and PL, rs(106) = 0.46, P = .001. However, there were no statistically significant correlations between pathology of the PTT and PB, rs(106) = 0.17, P = .08, or the PTT and PL, rs(106) = 0.14, P = .15. These findings suggest an intimate relationship between the AT, PTT, and the peroneal tendons. These individual anatomic structures may have underappreciated functional relationships that could lead to future investigations. LEVEL OF CLINICAL EVIDENCE: Level IV