Chapter 20 Ankle Joint and Foot

Bones and Landmarks Tibia Fibula Medial condyle Lateral condyle Crest Medial malleolus Fibula Head Lateral malleolus Interosseous membrane

Bones and Landmarks Tarsals (7) Calcaneus Talus Navicular Cuboid Calcaneal tuberosity Sustentaculum tali Talus Navicular Navicular tuberosity Cuboid Cuneiforms (3) Sustentaculum tali – medial calcaneus Navicular tuberosity - medial

Bones and Landmarks Metatarsals (5) Base Head Phalanges (14)

Functional Aspects of the Foot Hindfoot Midfoot Forefoot Hindfoot – initial contact with ground Midfoot – stability & mobility to transmit movement from hindfoot to forefoot Forefoot – adaptation to ground levels

Joints and Motions Ankle motions Plantar flexion/dorsiflexion (sagittal plane) Inversion/eversion (frontal plane) Adduction/abduction (transverse plane) Supination (plantar flexion, inversion, and adduction) Pronation (dorsiflexion, eversion, and abduction) True joint axis is oblique DF – 30-50 degrees; PF 20 degrees

Joints and Motions Ankle joints Talotibial joint Subtalar joint Transverse tarsal joint Talotibial – aka talocrural Subtalar – plane synovial joint; 1 degree of freedom (Inv/Ev) Transvere Tarsal – combines with subtalar to produce inversion/eversion Superior Tibiofibial Joint – plane joint; gliding & rotation; synovial joint Inferior Tibiofibial Joint – syndesmosis Consider OKC vs. CKC motion – Table 20-1 page 306

Joints and Motions Foot joints Metatarsophalangeal joints (MTP) Proximal interphalangeal joints (PIP) Distal interphalangeal joints (DIP)

Joints and Motions Foot motion MTP PIP and DIP flexion/extension/hyperextension/adduction, abduction PIP and DIP flexion and extension 1st MTP 45 degrees flex/ext; 90 degrees hyperextension 2nd-5th MTP – 40 degrees flex/ext; 45 degrees hyper extension

Ligaments and Other Structures Joint capsule Deltoid ligament (4 parts) Lateral ligament (3 parts) Arches Medial longitudinal arch Lateral longitudinal arch Transverse arch Deltoid Ligament - Anterior tibiotalar - Posterior tibiotalar - Tibionavicular - Tibiocalcaneal Lateral Ligaments - Anterior Talofibular - Posterior Talofibular - Calcaneofibular

Ligaments and Other Structures Plantar ligaments and aponeurosis Spring ligament Long plantar ligament Short plantar ligament Plantar aponeurosis Spring – aka Plantar calcaneonavicular ligament; supports medial arch Long Plantar – supports lateral arch Short Plantar – assists long plantar ligament Plantar aponeurosis – aka plantar fascia

Muscles of the Ankle and Foot Superficial posterior group Gastrocnemius Soleus Plantaris Deep posterior group Tibialis posterior Flexor hallucis longus Flexor digitorum longus Extrinsics – compartments Intrinsics – within the foot only Table 20-2 pg. 311

Muscles of the Ankle and Foot Anterior group Tibialis anterior Extensor hallucis longus Extensor digitorum longus Lateral group Peroneus longus Peroneus brevis Peroneus tertius

Muscles of the Ankle and Foot Intrinsic muscles Consist of 4 distinct layers Most are on plantar surface Fourth (deepest) layer consists of the dorsal and plantar interossei Table 20-5 page 318; not responsible for testing

Ankle Joint and Foot Anatomical relationships Summary of muscle innervation Table 20-4 page 317 prime movers Table 20-7 & Table 20-8 pp. 322-323 for innervations

Common Ankle Pathologies Shin splints Pes cavus/Pes planus Metatarsalgia Ankle sprain Ankle fracture Plantar fasciitis Shin Splints – generic; medial tibial stress syndrome Ankle fracture – bimalleolar or trimalleolar