Fact-sheet: Accessory soleus muscle

Updated on 10/03/2018 at 2:51 PM

Note : 0/10

Definition

Rare anatomic variant with a prevalence of 1 to 6%, bilateral in 30 to 50% of cases.

Origin: posterior surface of the tibia and/or deep aponeurosis of the soleus muscle, sometimes directly from the soleus muscle.
Course: descends medial to the soleus muscle and its tendon. It is separated from the latter by its own fascia and runs outside the flexor retinaculum.
Insertion: 5 types of insertion are described: on the superior surface of the calcaneus, either directly or via a tendon.
onto the Achilles tendon.
on the medial surface of the calcaneus via a long tendon, or more rarely directly.
on the medial and superior surface of the calcaneus via a bifid tendon.
rare forms of fusion with the plantaris muscle have been described.

Asymptomatic, most often.

Posterior ankle impingement.

Soft tissue mass within Kager's fat pad.

Echogenicity identical to the Achilles tendon

Surgical excision depending on the symptoms.