Rear lower leg muscles

The superficial posterior muscles of the lower leg are among them: In the area of the posterior lower leg muscles, the soleus and gastrocnemius muscles work closely together. They are synergists and are also referred to in anatomical terminology as the musculus triceps surae. The soleus muscle (plaice muscle) is largely covered by the gastrocnemius muscle, which is why it is only visible on the sides of the lower leg.

Its function is plantar flexion, i.e. pulling the foot down towards the sole of the foot. It is also responsible for lifting the inner edge of the foot while simultaneously lowering the outer one. The gastrocnemius muscle, also called the twin calf muscle, gives the human calf its characteristic shape.

In close cooperation with the soleus muscle, it causes the upper ankle joint to pull the foot down (plantar flexion), the lower ankle joint to raise the inner edge of the foot (supination) and the knee joint to flex. The gastrocnemius muscle has two muscle heads, which are called caput medial (inner head) and caput lateral (outer head) according to their position.Both originate from the lower part of the thigh bone. The calcaneus represents the base of the two united muscle bellies.

The Achilles tendon is the joint tendon of the gastrocnemius and soleus muscles. The plantar muscle is a muscle that is small and regressed in humans, but still strongly developed in monkeys. Not present in all humans, this muscle radiates into the aponeurosis plantaris, a tendon plate in the area of the sole of the foot.

The function of the musculus plantaris is almost meaningless in humans. It is only marginally involved in the flexion of the knee and the inward rotation of the lower leg in the flexed position.

Musculus soleus
Musculus gastrocnemius
Plantar Musculus

Deep layer

Belong to the deep layer of the rear lower leg muscles: The Musculus tibialis posterior, also called “posterior tibial muscle“, starts with its tendon, which runs through the so-called tarsal tunnel, at the scaphoid and sphenoid bone. Its tasks are the lowering (plantar flexion) of the foot and the lifting of the inner edge of the foot. The muscle flexor hallucis longus, Latin for “long big toe flexor”, is the strongest of the deep toe flexor muscles.

Its tendon crosses the tendon of the musculus flexor digitorum longus in the area of the sole of the foot (see below). At this point, the two flexor muscles are connected so that the flexor hallucis longus muscle reinforces the effect of the flexor digitorum longus muscle. In addition to bending the big toe downwards, the flexor hallucis longus muscle supports plantar flexion.

The “long toe flexor”, musculus flexor digitorum longus, bends all toes except the big toe towards the sole of the foot and supports plantar flexion (bending towards the sole of the foot) of the foot. Its tendon divides behind the tarsal tunnel, a canal bounded by bone and connective tissue in the area of the inner side of the ankle joint, into four tendons that finally reach the individual toes.

Posterior tibial muscle
Musculus flexor hallucis longus
Musculus flexor hallucis longus
Musculus flexor digitorum longus