An unusual variation of an additional plantaris originating from the soleus

The plantaris muscle belongs to the posterior superficial crural muscles, placed between the gastrocnemius and soleus. Its origin usually is from the inferior part of the lateral supracondylar line of the femur at a position a little superior to the origin of the lateral head of gastrocnemius. During routine dissection we came across a very interesting variation of the additional plantaris originating from the soleus. We observed that the additional muscle belly of the plantaris (actually a tendon) merged with the tendon of the main belly and inserted into the calcaneal tendon. This variation was observed in the left lower limb from a cadaver. The aim of this paper was to analyze and describe this rare and interesting finding.
We suppose that it is very important to consider the occurrence of above variation of the plantaris originating from the soleus. It would be helpful in cases of patients with an unexplained pain in lower leg and when surgical procedures are performed on this area.