Accessory Soleus: Posterior Ankle Pain in Two Adolescent Athletes

Abstract

Category: Sports Introduction/Purpose: Accessory soleus muscles are a rare cause of posterior ankle pain and swelling in adolescent athletes. The increased accessibility of MRI imaging has been a helpful aid its proper diagnosis and treatment. Different surgical treatment also exists including partial fasciotomy as well as surgical excision. This case report offers 2 cases of adolescent athletes with this finding causing pain and swelling in the posterior ankle limiting rigorous athletic activities that were treated with surgical excision of the accessory soleus. Methods: Two patients were evaluated in clinic for posterior ankle pain during participation in rigorous athletic activities. The first patient was a 13-year-old girl with posterior ankle pain and swelling while playing softball that limited her ability to pitch more than one inning. The second patient was a 17-year-old boy with posterior ankle pain and swelling that limited his ability to perform at peak performance during basketball games. Both patients had MRI evaluation of the ankles after months of no improvement with nonoperative treatment. MRI demonstrated accessory soleus muscles that was attributed to be the cause of their symptoms. After unsatisfactory symptom relief with nonoperative treatment measures, the two patients underwent surgical excision of the accessory soleus muscle. Results: Both patients underwent surgical excision of the accessory soleus muscle through a posteromedial approach. The accessory soleus muscle was found just anterior and medial to the Achilles tendon. The muscle was detached from its insertion into the calcaneus distally and traced back proximally. The muscle was then truncated proximally approximately 5-6 cm proximal to its insertion on the calcaneus. Both patients began weight bearing to tolerance in a walking boot immediately postoperatively. Both patients experienced resolution of their symptoms after surgical excision. Conclusion: Accessory soleus muscles are rare anomalous muscles of the posterior ankle that can cause pain and swelling with activity. Increased accessibility of MRI imaging has led to its diagnosis and treatment. Surgical excision is a reasonable surgical treatment option when nonoperative treatment fails to alleviate symptoms.