Kinesiology

Lesson 15 of 16

Leg, ankle, and foot

Below the knee, muscles control ankle and toe motion and help manage balance and propulsion. The anterior compartment dorsiflexes the ankle, the lateral compartment everts the foot, and posterior compartments plantar-flex the ankle and support inversion or toe flexion. The arches distribute load through coordinated bones, ligaments, and muscles. Respect foot sensitivity and screen for contraindications before treatment.

Key points

• Tibialis anterior dorsiflexes and inverts the foot.
• Gastrocnemius and soleus contribute to plantar flexion; gastrocnemius also crosses the knee.
• Fibularis longus and brevis evert the foot and support lateral ankle control.
• Tibialis posterior assists inversion and supports the medial arch.
• Long toe flexors and extensors coordinate digital motion with ankle position.
• Avoid foot work over wounds, acute inflammation, or suspected vascular problems.

Key terms

Tibialis anterior

O: lateral tibia and interosseous membrane; I: medial cuneiform and first metatarsal; A: dorsiflexes and inverts foot.

Gastrocnemius

O: medial and lateral femoral condyles; I: calcaneus via Achilles tendon; A: plantar-flexes ankle and flexes knee.

Soleus

O: posterior fibular head and soleal line of tibia; I: calcaneus via Achilles tendon; A: plantar-flexes ankle and supports postural control.

Fibularis longus

O: head and upper lateral fibula; I: plantar surfaces of medial cuneiform and first metatarsal; A: everts and plantar-flexes foot, supports transverse arch.

Tibialis posterior

O: posterior tibia/fibula and interosseous membrane; I: navicular and adjacent tarsal/metatarsal bases; A: inverts and plantar-flexes foot, supports medial arch.