Gastrocnemius muscle insertion via the Achilles tendon. The plantaris muscle and a portion of its tendon run between the two muscles, which is involved in "locking" the knee from the standing position. Since the anterior compartment of the leg is lateral to the tibia, the bulge of muscle medial to the tibia on the anterior side is actually the posterior compartment. The soleus is superficial to the mid-shaft of the tibia. 10% to 30% of individuals have a sesamoid bone called the "fabella" in the lateral (outer) head of gastrocnemius muscle. Along with the soleus muscle, the gastrocnemius forms half of the
Trapezium (bone) tubercle found on the anterior surface of the bone. It is where sometimes abductor pollicis brevis muscle attaches. The carpal bones function as a unit to provide a bony superstructure for the hand. The trapezium is the most radial of the bones surrounding the carpal tunnel. It is important in thumb movement. The trapezium is susceptible to arthritis at the joint with the metacarpal bone of the thumb, due to overuse. The etymology derives from the Greek "trapezion" which means "a little table", from "trapeza" meaning "table", itself from "(te)tra-" "four" and "pod-" "foot". The bone was first documented in