LEG+FOOT MYOLOGY Flashcards
Extrinsic muscle
Origin from the leg insertion within foot. A long muscle
Intrinsic muscle
Origin and insertion within the foot. A short muscle
Deep fascia of the leg
Around the knee the deep fascia is continuous with that of the leg
Band or sheath of connective tissue, primarily collagen fibres
Deep fascia attachments
- Encompasses leg mainly attaches to anterior and medial boarders of tibia
- Medial and lateral tibial condyles
- Head of Fibula
- Anteriorly to patella
- Both maleoli
- Blends with bone periosteum
Arrangement of deep facia and intermuscular septa
Arrangement of deep facia and intermuscular septa helps form muscle compartments- keeps them in correct position
Deep fascia
Tibia interosseous membrane and fibula
Tibia and Fibia connected by interosseous membrane which separates the anterior compartment from the posterior compartment smaller lateral compartment
Anterior compartment
Tibialis anterior Extensor hallucis longus Extensor digitirum longus Perineous tertius (fibularis tertius)
Superfical - posterior compartment
Gastrocnemius
Plantaris
Soleous
Deep- posterior compartment
Tibials posterior
Flexor hallucis longus
Flexor digitorum
Popliteus
Lateral compartment
Peroneal longus
Peroneal brevis
Anterior Nerve supply
deep peroneal nerve …..
Lateral compartment nerve supply
Superficial peroneal nerve L5,S1
Superficial posterior nerve supply
Tibial nerve S1,2
Retinaculae
Deep fascia in ankle is thickened to form transverley orientated bands
Three retinacula
1) Extensor
2) Peroneal
3) Flexor
Pulled tendons passing across all regions in position to prevent bowstringing
Tendons passing under the reticula are enclosed within a synovial sheath – facilitates gliding of tendons and protect them from wear and tear
Extensor retinaculum
Made of 2 bands
- Superior
- Inferior
Superior extensor retinaculum
Horizontal bands of deep fascia
Runs across extensor tendons passing between tibia and Fibula just above ankle joint
Inferior extensor retinaculum
Y shaped thickening
Stem upper surface of calcaneus attaching to floor of sinus tarsi
Upper band passes to medial malleolus
Lower band blends with deep facia on medial side of foot
Peroneal retinacula
Superior
Inferior
Superior peroneal retinacula
Attaches to lateral side of calcaneous to posterior border of lateral malleolus
Holds tendons off peroneus longus and brevis together within single synovial sheath
Inferior peroneal retinacula
Stretches over lateral surface of calcaneus attaching to peroneal tubercle
Forms 2 tunnels where peroneal longus and brevis enter
Above peroneal tubercle = brevis
Below= longus
Flexor retinaculum
Extends from posteriorly surface of medial maleolus to medial tubercle of calcaneous
Forms for tunnels for various blood vessels tendons etc departs into the foot
Most medial is tibialis posterior
Tendons and synovial sheaths
Each tendon is enclosed within its own synovial sheath
Peroneal retinaculum tendons are joint then differentiate into separate synovial sheaths
Plantar Aponeurosis
Thickening of the deep fascia on the sole of the foot (thickest 18 layers)
🔺apex at heel fibres run longitudinally towards toes
Important static stabiliser of the arches of the foot
Provides attachment for the intrinsic muscles of the foot
Plantar Aponeurosis
Attachments
Inferior aspect of calcaneous to the metatarsal-phalangeal become continuous with fibrous flexes of toes
Windlass mechanism
See diagram
Muscles in the layers of the foot
Layer 1
Layer 2
Layer 3
Layer 4