BLOCK 14 Ankle Joint 2012

Ankle Joint / Talocrural Joint Classification Synovial hinge joint Bones tibia, fibula, talus articular surfaces Tibia inferior surface lateral surface of the medial malleolus

Ankle Joint / Talocrural Joint Talus body has 3 articular surfaces for lateral malleolus, medial malleolus and inferior surface of the tibia Tibia & fibula forms a deep socket (mortise) into which the body of the talus fits. it is deepened by the inferior tibiofibular ligament Capsule fixed to the bones near the margins of the articular surfaces it is reinforced medially and laterally by ligaments

TIBIA Location Functions Proximal end Menisci Intercondylar eminence anteromedially Functions Weightbearing Mvmnt in 1 plane Proximal end Wide 2 condyles Intercondylar area Hyaline cartilage Medial condyle - Large, oval Lateral condyle – small, round Menisci Intercondylar eminence for cruciate ligaments & limits lateral mvmnt

Peripheral attachments Capsule Muscles Ligaments Menisci Inferior surface of lateral condyle Articular facet Tibial tuberosity Anterior & in midline Inferior to condyles Patellar ligament Bursae Beneath tendon & skin

Shaft Triangular x-section 3 borders 3 surfaces Upper 1/3 post surface Anterior subcutaneous Posterior Interosseous/lateral 3 surfaces Medial subcutaneous Lateral Upper 1/3 post surface Soleal line-oblique

Distal end Shaft expands Inferiorly Superiorly Medial malleolus which articulates with the talus but not wt bearing Inferiorly Rectangular articular facet - talus Superiorly Superior tibiofibular joint

FIBULA Location Functions Shape Proximal end Posterolateral to tibia Attachment of muscles Functions as a pulley distally for tendons Shape Irregular, triangular on x-section Proximal end Head-knob shaped Apex superiorly Articular facet medially, facing sup & ant – for lat condyle of tibia Neck-common peroneal nerve

Shaft 3 borders 3 surfaces Anterior border prominent-divides inferiorly to bound triangular subcutaneous surface above distal end Interosseous/medial border Posterior border (don’t confuse with medial ridge) 3 surfaces Anterior Posterior Lateral

Malleolar fossa posteromedially Distal end Lateral malleolus long, pointed, subcuta- neous, projects inferiorly, 10mm longer than medial malleolus Articular facets medially (for talus) Superiorly (for tibia) Malleolar fossa posteromedially

Ankle Joint / Talocrural Joint Ligaments Medial deltoid ligament: strong, fan-shaped sup attachments=apex to tip of medial malleolus inf attachments=medial side of talus sustentaculum tali spring ligament / plantar calcaneonavicular ligament tuberosity of navicular

Ankle Joint / Talocrural Joint Ligaments Lateral weaker ligament consists of three bands: ant talofibular calcaneofibular post talofibular

Ankle Joint / Talocrural Joint Synovial membrane lines the capsule expands upwards in front of the interosseous ligament of the inferior talofibular joint Nerve supply deep fibular nerve tibial nerve Blood supply malleolar brrs of ant tibial artery posterior tibial artery fibular artery

Ankle Joint / Talocrural Joint Relationships Anterior tibialis anterior extensor hallucis longus vena comitantes ant tibial artery vena comtantes deep fibular nerve extensor digitorum longus peroneus tertius great saphenous vein

Ankle Joint / Talocrural Joint Relationships Posterior calcaneal tendon peroneus longus Posterolateral (behind lat malleolus) peroneus brevis

Ankle Joint / Talocrural Joint Relationships Posteromedial (behind medial malleolus) tibialis posterior flexor digitorum longus vena comitantes posterior tibial artery tibial nerve flexor hallucis longus

Ankle Joint / Talocrural Joint Movements Dorsiflexion tibialis anterior extensor digitorum longus peronius tertius

Ankle Joint / Talocrural Joint Movements Plantarflexion gastrocnemius plantaris tibialis posterior flexor digitorum longus flexor hallucis longus peroneus longus peroneus brevis

ANKLE INJURIES

Osteology Ligaments INJURY Orthopaedics Muscles DIAGNOSIS

Joints of the Foot Classification Bones Articular surfaces Synovial plane joint Bones talus that rests on the calcaneus Articular surfaces inferior surface of the talus superior surface of the calcaneus

Joints of the Foot Capsule Synovial membrane Movements encloses the joint is attached to the margins of the articular surfaces Synovial membrane lines the capsule Movements inversion eversion

FOOT Function Number of bones Locomotion Weightbearing 7 tarsals 5 metatarsals 14 phalanges

Tarsal bones Mvmnts Calcaneus, navicular, cuboid, cuneiform Articulates with tibia, fibula & calcaneus Rests on calcaneus Posterior end: forms heel Anterior end: transverse tarsal joint Mvmnts Eversion, inversion

Metatarsals Introduction Function Head Phalanges Forms anterior part of longitudinal arches Numbered I – V medial to lateral Function Transmits wt of body in erect position to ground Head Articulate with proximal phalanges Heads are joined by transverse ligament Head of 1st metatarsal rests on 2 sesamoid bones which transmits wt to the ground Phalanges 2 in big toe, 3 in other toes Each phalanx has a base, shaft, head

Joints of the Foot Ligaments medial talocalcaneal lateral talocalcaneal posterior talocalcaneal interosseous talocalcaneal attached to the sulcus tali above & calcaneal sulcus below strong ligament calcaneal sulcus + sulcus tali = tarsal sinus

Midtarsal Joints = 2 parts Talocalcaneonavicular Joint head of talus articulates with posterior surface of navicular superior surface of spring ligament superior surface of sustentaculum tali all 3 facets are surrounded by a single jnt capsule joint contains dorsal talonavicular ligament plantar calcaneonavicular ligament

Midtarsal Joints = 2 parts Calcaneocuboid Joint between calcaneus (ant surface) & cuboid (post surface) supported by: long plantar ligament plantar surface of calcaneus to ridge on cuboid bone superficial fibers bridge a groove to transform it into a tunnel & then insert on the bases of Metatarsals II,III,IV (V)

Midtarsal Joints = 2 parts short plantar ligament calcaneocuboid passes deep to long plantar ligament fan-shaped from calcaneus (ant tubercle) to cuboid (just proximal to the groove) movements inversion eversion

Medial Arch calcaneus talus 3 cuneiform bones metatarsal I

Lateral Arch calcaneus cuboid metatarsal IV & V

Transverse Arch metatarsal bases cuboid cuneiform bones

Arches of the foot Medial arch Lateral arch Transverse arch Longitudinal arches Transverse arches Medial arch More marked Supported by ligaments, calf tendons, foot muscles Calcaneus, talus, navicular, 3 cuneiforms, 3 medial metatarsals Lateral arch Supported by ligaments Calcaneus, cuboid, 2 lateral metatarsals Transverse arch Highest & most marked @ metacarpal bases Supported by ligaments & tendon of a calf muscle

Sole of the Foot Skin Subcutaneous tissue Thick No hair Contains many sweat glands Subcutaneous tissue Fibrous Septa that form lobuli filled with fat Fat is under pressure and bulges out when cut Serves as a shock absorber Septa anchors the skin to plantar aponeurosis enhancing grip of the sole

Sole of the Foot Plantar aponeurosis Origin = calcaneus Insertion = base of the toes Thickest in the center Functions Firm attachment of skin Protects blood vessels and nerves Helps maintain the arches

Muscles of the sole of the Foot – 4 Layers Layer I Abd hallucis Abd digiti minimi Flexor digitorum brevis

Muscles of the sole of the Foot – 4 Layers Layer II Flexor digitorum longus Flexor hallucis longus Quadratus plantae lumbricals

Muscles of the sole of the Foot Layer III Flexor hallucis brevis Adductor hallucis Flexor digiti minimi

Foot - Muscles of the sole Layer IV Flexor hallucis brevis Adductor hallucis Flexor digiti minimi