Foot, Ankle, Shin & Calf Anatomy PDF

Foot, Ankle, Shin & Calf SS202 Siobhán O’Connor MSc PhD Certified Athletic Therapist (CAT) Movements of the Foot and Ankle • Plantar flexion • Dorsiflexion • Inversion • Eversion • Supination • Pronation •Functional movement • Jumping • Running • Kicking Bones of the Foot 26 bones plus two ses...

Foot, Ankle, Shin & Calf SS202 Siobhán O’Connor MSc PhD Certified Athletic Therapist (CAT) Movements of the Foot and Ankle • Plantar flexion • Dorsiflexion • Inversion • Eversion • Supination • Pronation •Functional movement • Jumping • Running • Kicking Bones of the Foot 26 bones plus two sesamoids (base of the toe) • 7 Tarsals • Talus • Calcaneus • Navicular • Cuboid • Cuneiform • Medial • Intermediate • Lateral • 5 Metatarsals • 14 Phalanges • Proximal/Middle/Distal • (X4) • Proximal/Distal in Hallux (big toe) Bones of the foot • Phalanges • Sesamoids • Metatarsals • Tarsals - Cuneiforms - Cuboid - Navicular - Talus - Calcaneus Joints of the Forefoot • Interphalangeal joint - Head of proximal phalanx with base of next distal phalanx - Flexion and extension of the toes • Metatarsophalangeal Joint - Rounded head of metatarsals and base of proximal phalanx - Flexion and extension of the toes Joints of the Forefoot – Tarsometatarsal Joints • Articulating Surface - Anterior surface of cuboid and cuneiforms with base of metatarsals • Movements -The joints are relatively rigid, except for the first, which allows moderate amounts of dorsiflexion and plantar flexion, coupled with small amounts of inversion and eversion Joints of the Forefoot –Distal intertarsal joints • Cuneocuboid joint • Cuneonavicular joint • Intercuneiform joint • Compromises the: • talocalcaneonavicular & calcaneocuboid joints acting as a single function unit • Movements - Movement at this joint is always accompanied by movement at the subtalar joint - Inversion of the forefoot achieved by adduction of the foot at the subtalar joint and supination of forefoot at midtarsal joint; plantarflexion at ankle increases inversion - Eversion of the forefoot achieved by abduction of the foot at the subtalar joint and pronation of forefoot at midtarsal joint; dorsiflexion at ankle increases eversion Transverse (mid) tarsal joint Subtalar joint • Articulating Surface - Concave facet on under surface of the talus, convex facet on the upper surface of the calcaneus • Movements - Inversion and eversion of the foot Ankle Joint • Articulating Surface - Tibia, fibular & talus • Movements - Dorsiflexion (20-30 degrees) and plantarflexion (30-50 degrees) The Tibia Tibia Medial Malleolus • Medial malleolus is the distal projection of the tibia • It provides medial stability for the ankle The Fibula • Lateral Malleolus is the lateral projection at the distal end of the fibula • Lateral malleolus provides lateral stability to the ankle Fibula Lateral Malleolus The Talus Talus • Large talus transmits the weight of the body from the tibia to the toes • Tib & Fib above and sides • Navicular in front • Calcaneus below • No muscle attachments • Ligaments - Lateral ligament complex ➢Anterior talofibular (ATFL) ➢Calcaneofibular (CFL) ➢Posterior talofibular (PTFL) - Medial ligament complex (deltoid ligaments) • Stability - By ligaments and muscles Bones of the Shin • Tibia • Medial side • Larger than fibula • Tibial Tuberosity • Fibula • Lateral side • Smaller than tibia • Head of Fibula Tibia and Fibula Transverse View Proximal Tibiofibular Joint • Head of fibula and lateral condyle of tibia • During ankle dorsiflexion: • Rotation • Proximal fibula externally rotates • During knee flexion: • Translation • Proximal fibula moves anterior Common Peroneal Nerve • Curves around head of fibula • Divides into Superficial and Deep branches • Why you should not leave ice on head of fibula for too long? Interosseous Membrane • Between the tibia and fibula • Separates the muscles on the front from those on the back of the leg. • Fibers run downwards and laterally • Broader above than below • Oval space so anterior tibial vessels can travel to the front of the leg The Inferior TibioFibular Joint Inferior Tibfib Joint • Joint between distal part of tibia and fibula • Supported by the inferior tibiofibular ligaments and syndesmosis • Anterior • Lateral • Posterior Compartments of the Lower Leg • Superficial • Deep • Tibialis Posterior Compartment (queried 5th compartment) Muscles that Plantarflex • The top of the foot reaches away from the shin and the toes/toe mounds point. • Peronius longus • Peronius brevis • Tibialis posterior • Flexor hallucis longus • Flexor digitorum longus • Gastrocnemius • Soleus Tibialis Posterior • Origin: Interosseous membrane, lat aspect of posterior surface of tibia, proximal 2/3 of medial surface of fibula • Insertion: Tuberosity of navicular bone, sustentaculum talo, 3 cuneiforms, cuboid and bases of 2nd-4th MT • Action: Inversion and assists plantarflex of ankle Gastrocnemius • Origin: • Lateral head: lateral aspect of the lateral condyule of the femur • Medial head: popliteal surface of the femur, superior to medial condyle. • Insertion: Posterior surface of calcaneus via Achilles tendon • Action: Plantarflex ankle, flexes knee Soleus • Origin: Posterior aspect of head of fibula, superior fourth of post surface of fibula, medial line and medial border of tibia • Insertion: Posterior surface of calcaneus via Achilles tendon • Action: Plantarflex ankle, steadies leg on foot • Plantaris: weakly assists gastroc in plantarflexing ankle & flexing the knee. Muscles that Dorsiflex • The foot is drawn up towards the shin and the heel sharpens. Muscles: • Tibialis anterior • Extensor hallucis longus • Extensor digitorum longus • Peronius tertius Tibialis Anterior • Origin: Lat condyle and prox half of lat surface of tibia & interosseous membrane • Insertion: Cuneiform bone, base of 1st MT bone • Action: Dorsiflex ankle jt. Assists in inversion Muscles that Invert • The sole of the foot turns inward towards the midline of the body. The inner foot, inner ankle and inner heel shorten. Muscles: • Tibialis anterior • Extensor hallucis longus • Flexor hallucis longus • Flexor digitorum longus Muscles that Evert • The sole of the foot turns away from the midline and the inner foot, inner ankle and inner heel lengthen. The outer foot sharpens. Muscles: • Extensor digitorum longus • Peronius tertius • Peronius longus • Peronius brevis Peroneus Longus • Origin: Lateral condyle of tibia & head and proximal 2/3 of lat surface of fibula • Insertion: Lateral side of base of 1st MT and medial cuneiform • Action: Eversion. Assists in plantarflex of ankle jot Peroneus Brevis • Origin: Distal 2/3 of lat surface of fibula • Insertion: Tuberosity of base of 5th MT bone • Action: Eversion. Assits in plantarflex of ankle • Extensor hallucis longus (IP,MTP) Toe Extension • Extensor Digitorum Longus (DIP, PIP, MTP) • Extensor Digitorum Brevis (DIP, PIP, MTP) • Lumbricals (DIP, PIP) Extensor Hallucis Longus • Origin: middle 2/4’s of anterior surface of fibula and adj interosseous membrane • Insertion: Base of distal hallux • Action: Extends Mtphal and interphal jts of hallux. Assists inv and dorsiflex of ankle Extensor muscles of the Toes • Extensor Digitorum Longus • Origin: Lateral condyle of tibia, proximal ¾ of anterior surface of fibula, proximal part of interosseous membrane and adj intermuscular septa • Insertion: 4 tendons to 2nd-5th digits. Each form an expanson on dorsal surface of toe, base of middle phalanx and distal phalanx • Action: Extends MT jts. Assists dorsiflex and eversion of ankle Toe Flexion • Flexor digitorum longus (DIP, PIP, MTP) • Flexor digitorum brevis (PIP, MTP) • Flexor hallucis longus (IP, MTP) • Flexor hallucis brevis (MTP) • Flexor accessories (DIP, PIP, MTP) • Flexor digiti minimi brevis (MTP) • Interossei (MTP) • Lumbricals (MTP) Flexor Digitorum Longus • Origin: Middle 3/5’s of post surface of tibia • Insertion: Bases of distal phalanges of 2nd-5th digits • Action: Flexes prox and distal interpahl and Mtphal jts of 2nd-5th digits. Assists in plantarflex and inv of ankle Flexor Hallucis Longus • Origin: Post surface of distal 2/3 of fibula, interosseous membrane • Insertion: Base of plantar aspect distal phalanx of hallux • Action: Flexes interphal jt of hallux & assists flex of MT jt and plantarflex and inversion of ankle jt