- See: Anterior Compartment:
- origin: lateral condyle of tibia, proximal 2/3 of lateral surface of tibia, interosseous membrane, deep fascia and
lateral intermuscular septum;
- insertion: plantar surface on base of first metatarsal and medial plantar surface of 1st cuneiform;
- action: dorsiflexes and inverts foot at the ankle;
- reversed origin insertion action:
- when standing, the foot is fixed & becomes origin;
- action causes forward body lean antagonistic to plantar flexion of soleus and gastrocnemius;
- active in balance mechanism of anterior and posterior sway;
- nerve supply: peroneal, L4 > L5, S1; (see Innervation)
- synergists: extensor hallucis longus, externsor digitorum longus;
- Discussion: Paralysis:
- may occur from polio;
- paralysis results in loss of dorsiflexor & invertor power & results in development of equinovalgus deformity;
- this is seen initially during swing phase of gait as moderate equinovalgus with forefoot eversion;
- later w/ more severe disease this will be seen in both phases of gait;
- to compensate, long toe extensors, function as dorsiflexors & become overactive during swing phase;
- hyperextension of the proximal phalanges and depression of the metatarsal heads results;
- contracture of ankle gradually develops as functioning triceps contracts;
- occassionally, the unopposed activity of the peroneus longus, which depresses the first metatarsal, combines with an
active tibialis posterior to cause formation of a cavovarus deformity;
- transferthe EHL tendon to bases of the first metatarsal;
- when peroneus tertius is functioning, it may be transferred along w/ EHL to the base of the first metatarsal;
- plantar fasciotomy may be needed
- when foot is severly relaxed or when the valgus deformity is fixed, tendon transfer is combined w/ triple arthrodesis ;
- Ruptured Tibial Anterior:
- symptoms of a ruptured tibialis anterior tendon are a sudden sharp pain and swelling over the first cuniform, accompanied by an
inability to coordinate normal foot motion;
- Role of Tibialis Anterior in Club Foot:
- anterior tibial muscle has a strong supinatory action when abnormal relationship between the talus & calcaneus is not been
The results of transfer of the tibialis anterior to the heel in patients who have a myelomeningocele.
Adult-onset hemiplegia: changes in gait after muscle-balancing procedures to correct the equinus deformity.
Posterior transfer of the anterior tibial tendon in children who have a myelomeningocele.
Combined split anterior tibial-tendon transfer and intramuscular lengthening of the posterior tibial tendon. Results in patients who have a varus deformity of the foot due to spastic cerebral palsy.
Pathophysiology of Charcot-Marie-Tooth disease.
Transfer of the tibialis anterior for calcaneus deformity in myelodysplasia.
Original Text by Clifford R. Wheeless, III, MD.
Last updated by Data Trace Staff on Tuesday, September 27, 2016 12:09 pm