An unilateral rare variant of plantaris muscle belly and its entrapment: A Clinico - Anatomical study

Abstract

The plantaris muscle is known to be one of the superficial flexors of the lower limb which is exceedingly variable in origin. Normally it has a single fusiform belly with a long narrow tendon that crosses obliquely between gastrocnemius and soleus muscle. These flexors muscles are supplied by the tibial nerve which is a branch of sciatic nerve and the tibial nerve runs superficially to the plantaris tendon. In the present case, we have observed a rare variant of plantaris muscle that comprises dual bellies sharing a common tendon instead of a single fusiform belly. Not only dual bellies of the muscle but also we have observed the muscle bellies were entrapped by the tibial nerve and its branch. So, prior knowledge of such anatomical variations should be borne in mind while conducting surgical procedures involving popliteal fossa and posterior compartment of the leg. It will also help the clinicians to diagnose muscle tears by interpreting the MRI scans and ultrasounds.