Tibialis anterior muscle
leg. Lying superficially in the leg, this muscle is easily palpable lateral to the anterior border of tibia. Along with fibularis (peroneus) tertius, extensor digitorum longus and extensor hallucis longus, it comprises the anterior (or extensor) compartment of the leg.Tibialis anterior is a fusiform muscle found in the anterior part of the
This muscle acts as the main foot dorsiflexor on the talocrural joint, but it also inverses the foot at the subtalar joint. Both actions play important roles in the gait cycle.
This article will discuss the anatomy and function of tibialis anterior muscle.
|Origin||Lateral surface of tibia, interosseous membrane|
|Insertion||Medial cuneiform bone, base of metatarsal bone 1|
|Action||Talocrural joint: foot dorsiflexion; subtalar joint: foot inversion|
|Innervation||Deep fibular nerve (L4, L5)|
Branches of anterior tibial artery: Anterior and medial muscular branches; anterior tibial recurrent, dorsalis pedis and anterior medial malleolar arteries
Branches of posterior tibial artery: Medial malleolar and calcaneal arteries
- Origin and insertion
- Blood supply
- Clinical notes
Origin and insertion
Tibialis anterior arises from several sites;
- Lateral tibial condyle
- Superior two thirds of the lateral surface of tibia
- Anterior surface of interosseous membrane
- Deep surface of deep fascia of the leg
- Anterior intermuscular septum.
It courses inferiorly down the leg, giving off a cord-like tendon at the distal third of the tibia. The tendon travels across the ankle and dorsum of the foot to insert on the medial cuneiform bone and the adjoining of base of the first metatarsal.
Tibialis anterior muscle lies medial to extensor digitorum longus and extensor hallucis longus, which makes it the most medial muscle in the anterior compartment of the leg. It also covers the anterior tibial vessels and deep fibular nerve in the proximal part of the leg.
The tendon of tibialis anterior usually passes beneath the extensor retinaculum which holds it in place. However, in some cases, the superficial and deep layers of the extensor retinaculum form a separate tunnel for the muscle’s tendon. It’s worth mentioning that this is the only extensor tendon that has its own synovial sheath at the level of the superior extensor retinaculum. The sheath extends from above the superior extensor retinaculum to the level of the talonavicular joint.
Arterial supply of the tibialis anterior is rather complex;
- The body of the muscle is entirely supplied by the branches of anterior tibial artery; anterior muscular, medial muscular branches and anterior tibial recurrent artery
- The tendon is mainly supplied by the branches of anterior tibial artery but also by the branches of posterior tibial artery. The former are the anterior medial malleolar artery and network, dorsalis pedis artery and medial tarsal arteries. The latter are the medial malleolar and calcaneal arteries.
Tibialis anterior dorsiflexes the foot at the talocrural joint and inverts it at the subtalar joint. It plays an important role in the activities of walking, hiking and kicking the ball by stabilizing the ankle joint as the foot hits the floor and pull it clear of the ground as the leg continues moving. It also supports the medial part of the longitudinal arch of the foot during any movement.
Anterior tibial stress syndrome
Excessive physical activity, especially among runners and military personnel, results in repetitive microtrauma of the tibialis anterior, causing a pain along the anterior edge of the tibia known as anterior shin splints or anterior tibial stress syndrome. It generally resolves spontaneously during periods of rest, although nonsteroidal anti-inflammatory drugs (NSAIDs) and ice might be used as a symptom-relieving treatment. Shin splints are associated with small tears in the tibial periosteum which explains why stress fractures can occur as a complication.