| Tarsal tunnel | |
|---|---|
 Medial view of the ankle. The structures within the tarsal tunnel are depicted. | |
Dissection video (1 min 55 s) | |
| Details | |
| Identifiers | |
| Latin | canalis tarsi |
| Anatomical terminology | |
The tarsal tunnel is a passage found along the inner leg underneath the medial malleolus of the ankle.
The roof of the tarsal tunnel is formed by the flexor retinaculum of the foot. [1] The floor of the tarsal tunnel is formed by the medial malleolus and the calcaneus. [1]
The tibial nerve, posterior tibial artery, posterior tibial vein, and flexor tendons travel in a bundle along this pathway through the tarsal tunnel, in the following order from anteromedial to posterolateral:
In the tunnel, the tibial nerve splits into three different paths. [3] The medial calcaneal branches of the tibial nerve continues to the heel, while the medial plantar nerve and the lateral plantar nerve continue on to the bottom of the foot. [3]
Tarsal tunnel syndrome is the most commonly reported nerve entrapment of the ankle. It is analogous to carpal tunnel syndrome in the wrist. It is caused by compression of the tibial nerve underneath the flexor retinaculum of the foot. [1] People with tarsal tunnel syndrome have pain in the plantar aspect of the foot mostly at night. Weight bearing increases pain and weakness is found on intrinsic foot muscles with positive Tinel sign at the tunnel. There is no tenderness present on the plantar foot, though this is typically the primary site of complaint.
The leg is the entire lower limb of the human body, including the foot, thigh or sometimes even the hip or buttock region. The major bones of the leg are the femur, tibia, and adjacent fibula. The thigh is between the hip and knee, while the calf (rear) and shin (front) are between the knee and foot.
In human anatomy, the fibularis longus is a superficial muscle in the lateral compartment of the leg. It acts to tilt the sole of the foot away from the midline of the body (eversion) and to extend the foot downward away from the body at the ankle.
In human anatomy, the ulnar nerve is a nerve that runs near the ulna bone. The ulnar collateral ligament of elbow joint is in relation with the ulnar nerve. The nerve is the largest in the human body unprotected by muscle or bone, so injury is common. This nerve is directly connected to the little finger, and the adjacent half of the ring finger, innervating the palmar aspect of these fingers, including both front and back of the tips, perhaps as far back as the fingernail beds.
The ankle, the talocrural region or the jumping bone (informal) is the area where the foot and the leg meet. The ankle includes three joints: the ankle joint proper or talocrural joint, the subtalar joint, and the inferior tibiofibular joint. The movements produced at this joint are dorsiflexion and plantarflexion of the foot. In common usage, the term ankle refers exclusively to the ankle region. In medical terminology, "ankle" can refer broadly to the region or specifically to the talocrural joint.
The tibialis posterior muscle is the most central of all the leg muscles, and is located in the deep posterior compartment of the leg. It is the key stabilizing muscle of the lower leg.
The posterior tibial artery of the lower limb is an artery that carries blood to the posterior compartment of the leg and plantar surface of the foot. It branches from the popliteal artery via the tibial-fibular trunk.
In human anatomy, the dorsalis pedis artery is a blood vessel of the lower limb. It arises from the anterior tibial artery, and ends at the first intermetatarsal space. It carries oxygenated blood to the dorsal side of the foot. It is useful for taking a pulse. It is also at risk during anaesthesia of the deep peroneal nerve.
The tibial nerve is a branch of the sciatic nerve. The tibial nerve passes through the popliteal fossa to pass below the arch of soleus.
Tarsal tunnel syndrome (TTS) is a nerve entrapment syndrome causing a painful foot condition in which the tibial nerve is compressed as it travels through the tarsal tunnel. This tunnel is found along the inner leg behind the medial malleolus. The posterior tibial artery, tibial nerve, and tendons of the tibialis posterior, flexor digitorum longus, and flexor hallucis longus muscles travel in a bundle through the tarsal tunnel. Inside the tunnel, the nerve splits into three segments. One nerve (calcaneal) continues to the heel, the other two continue on to the bottom of the foot. The tarsal tunnel is delineated by bone on the inside and the flexor retinaculum on the outside.
The flexor hallucis longus muscle (FHL) attaches to the plantar surface of phalanx of the great toe and is responsible for flexing that toe. The FHL is one of the three deep muscles of the posterior compartment of the leg, the others being the flexor digitorum longus and the tibialis posterior. The tibialis posterior is the most powerful of these deep muscles. All three muscles are innervated by the tibial nerve which comprises half of the sciatic nerve.
The flexor digitorum longus muscle is situated on the tibial side of the leg. At its origin it is thin and pointed, but it gradually increases in size as it descends. It serves to flex the second, third, fourth, and fifth toes.
In human anatomy, the fibularis brevis is a muscle that lies underneath the fibularis longus within the lateral compartment of the leg. It acts to tilt the sole of the foot away from the midline of the body (eversion) and to extend the foot downward away from the body at the ankle.
The flexor retinaculum is a fibrous band on the palmar side of the hand near the wrist. It arches over the carpal bones of the hands, covering them and forming the carpal tunnel.
The sole is the bottom of the foot.
The inferior extensor retinaculum of the foot is a Y-shaped band placed in front of the ankle-joint, the stem of the Y being attached laterally to the upper surface of the calcaneus, in front of the depression for the interosseous talocalcaneal ligament; it is directed medialward as a double layer, one lamina passing in front of, and the other behind, the tendons of the peroneus tertius and extensor digitorum longus.
The flexor retinaculum of foot is a strong fibrous band in the foot.
The saphenous nerve is the largest cutaneous branch of the femoral nerve. It is derived from the lumbar plexus (L3-L4). It is a strictly sensory nerve, and has no motor function. It commences in the proximal (upper) thigh and travels along the adductor canal. Upon exiting the adductor canal, the saphenous nerve terminates by splitting into two terminal branches: the sartorial nerve, and the infrapatellar nerve. The saphenous nerve is responsible for providing sensory innervation to the skin of the anteromedial leg.
The deltoid ligament is a strong, flat, triangular band, attached, above, to the apex and anterior and posterior borders of the medial malleolus. The deltoid ligament supports the ankle joint and also resists excessive eversion of the foot. The deltoid ligament is composed of 4 fibers:
A malleolus is the bony prominence on each side of the human ankle.
In the human body, the carpal tunnel or carpal canal is a flattened body cavity on the flexor (palmar/volar) side of the wrist, bounded by the carpal bones and flexor retinaculum. It forms the passageway that transmits the median nerve and the tendons of the extrinsic flexor muscles of the hand from the forearm to the hand. There are described cases of the anatomical variant median artery occurrence.
