Accessory soleus muscle: a case report and review of the literature

Abstract

Accessory soleus muscle is a rare condition which presents as a soft-tissue mass medial to the calcaneum and distal Achilles tendon. Though congenital in origin, it manifests in the second and third decades of life as a soft-tissue mass due to muscle hypertrophy. Patients may be asymptomatic or present with a painful ankle mass. It is important to be aware of this condition when interpreting CT or MRI of the ankle, which show characteristic findings of a normal muscle in an abnormal location.

The accessory soleus muscle causing tibial nerve compression neuropathy: A case report

“…It may simulate a soft tissue tumour with a differential diagnosis that includes lipoma, ganglion, haemangioma, synovioma and sarcoma. 3,4 It may also be a cause of recurrent tarsal tunnel syndrome, and failure of tarsal tunnel decompression has been shown to be due to the presence of an undiagnosed accessory soleus. 5 The anatomical variants have been described by Sookur et al 6 This accessory muscle may originate from the anterior fascia of the soleus muscle; the posterior aspect of the head and upper shaft of the fibula; the soleal line of the tibia; and the middle third of the medial border of the tibia.…”

“…1 It may be unilateral or bilateral and although congenital, it is usually asymptomatic and may only present in the second to third decade of life, possibly due to the increased muscle mass and activity during this period. 2 It may mimic a soft tissue tumour of the lower leg 3 and present with painful syndromes of the calf, ankle and foot. 4 We present a case report of a patient with a unilateral accessory soleus associated with neurological symptoms of his foot.…”

The Accessory Soleus Muscle: Case Report and a Review of the Literature

“…Dunn highlighted the clinical significance of the accessory soleus muscle and, subsequent to that work, the anatomical and orthopedic literature became enriched with several other clinical records of its occurrence (Gordon & Matheson, 1973;Ayala et al, 1982;Percy & Telep, 1984;Romanus et al, 1986;Petterson et al;Lorentzon & Wirell;Vanek & Fourré;Motto & Holloway;Pla et al;Garg & Kilcoyne;Palaniappan et al;Chotigavanichaya et al, 2000;Dos Remédios & Jolly, 2000;Kendi et al;Kouvalchouk et al).…”

“…John & Borrelli (1999) stated that the accessory soleus muscle is infrequently observed and reported, clinically. According to Palaniappan et al (1999), it was a chance finding that could be confounded with a soft-tissue tumor. Dunn (1965) was the first to demonstrate that the accessory soleus muscle was involved in painful syndromes of the lower limbs.…”

“…According to Boisgard et al, between 1869 and1995, there were reports of 100 symptomatic cases. The English-language literature has been the principal source of anatomical and clinical records regarding the accessory soleus muscle (Lorentzon & Wirrell, 1987;Chittaranjan et al, 1994;Sekiya et al, 1994;Pla et al;Garg & Kilcoyne;Palaniappan et al;John & Borrelli;Kendi et al;Christodoulo et al;Kouvalchouk et al).…”