Bilateral accessory soleus: a report on four patients with partial fasciectomy

Four young adults (average age 24 years) presented with complaints of posterior ankle pain after running. Bilateral accessory soleus muscles were diagnosed using magnetic resonance imaging or CT scan. Symptoms were present an average of 3 years before diagnosis. Two patients had previous surgery (ankle arthroscopy, tarsal tunnel release, and leg compartment release) before diagnosis and treatment. Obliteration of Kager's triangle (posterior ankle fat pad) was present on six out of eight lateral ankle radiographs. Posteromedial prominence was present on four out of eight ankles. Operative exploration confirmed the presence of five muscles and fasciectomy was performed. Follow-up (17 to 29 months) showed good relief of symptoms in all patients and return to long-distance running for three patients. Dissection of 47 preserved cadavers revealed three accessory soleus muscles in the 94 extremities (two muscles were bilateral in one cadaver).