Anterior/posterio Compartment Of Leg, Lateral Compartment Of Leg And Foot Flashcards
Compartments of the leg
Anterior compartment (anterior tibial vessels, deep fibular nerve) Lateral compartment (superficial fibular nerve) Posterior compartment (deep and superficial: posterior tibial vessels and tibial nerve)
Divisions of the Compartments of the Knee
Interosseous membrane: Divides anterior compartment with deep posterior compartment
Anterior Crural septum: divides anterior and lateral compartments
Posterior crural septum: divides lateral compartment with deep and superficial posterior compartment
Intermuscular septum: divides deep and superficial posterior compartments
Anatomy of anterior compartment of the leg
Muscle Actions: dorsiflexors of the foot, extensors of the digits (also invert and evert)
Nerve: deep fibular nerve
Blood Supply: anterior tibial artery
Trick to remember what muscles are major invertors and evertors of the ankle
TibIalis muscle: Invertor (I’s)
Fibularis (pEroneus) muscle: Evertor
Tibialis anterior
Anterior compartment of leg
Prox: lateral condyle of the tibia
Distal: medial cuneiform and base of 1st metatarsal
Innervation: deep fibular nerve
Action: dorsiflexes the ankle and inverts the foot
Extensor digitorum longus
Anterior compartment of leg
Prox: lateral condyle of tibia and proximal fibula
Distal: phalanges of toes 2-5
Innervation: deep fibular nerve
Action: extends lateral four digits and dorsiflexes ankle
Extensor hallucis longus
Anterior compartment of the leg
Prox: fibula
Distal: base of distal phalanx of great toe (Hallux)
Innervation: deep fibular nerve
Action: extends great toe and dorsiflexes ankle
Fibularis Tertius
Ant. Compartment of Leg
Prox: distal fibula
Distal: 5th metatarsal
Innervation: deep fibular nerve
Action: dorsiflexes ankle and aids in eversion of foot
Superior Extensor Retinaculum
Extends across tendons superior to the ankle joint
Inferior Extensor Retinaculum
At level of the ankle joint
Anatomy of the Lateral Compartment of the Leg
Muscle: plantar flexors and principal evertors of the foot
Nerve: superficial fibular
Blood supply: no specific artery in this compartment (fibular branch of the posterior tibial artery supplies the compartment)
Fibularis Longus
Lateral compartment of leg
prox: fibular head and shaft
Distal: 1st metatarsal and medial cuneiform
innervation: superficial fibular nerve
Action: everts foot and weakly plantarflexes
Fibularis Brevis
Lateral compartment of the leg
Prox: distal fibula
Distal: tuberosity of the 5th metatarsal bone
Innervation: superficial fibular nerve
Action: everts foot and weakly plantarflexes
Superficial Fibular Nerve
Origin: Common fibular nerve
Arises: btwn fibularis longus and neck of fibular and descends in the lateral compartment of the leg; pierces deep fascia in distal third of leg to become cutaneous
Supplies lateral compartment muscles; skin on distal third of anterior surface of leg and dorsum of foot
Deep Fibular Nerve
Origin: common fibular nerve
Arises: btwn fibularis longus and neck of fibula; passes through the extensor digitorum longus and descends on the interosseous membrane; crosses the distal end of the tibia and enters the dorsum of foot
Supplies the anterior compartment of the leg muscles; skin of first interdigital cleft on dorsum of the foot
Anterior Tibial Artery
Origin: popliteal artery
Passes between tibia and fibula into anterior compartment through a gap in the superior part of the interosseous membrane and descends on this membrane between the tibialis anterior and extensor digitorum longus muscles
Supplies anterior compartment
Anatomy of the posterior compartment of the leg
Muscles: plantarflexors; 2 flexors of the digits of the foot
Attach: to calcaneus via tendo calcaneus (superficial group); tarsal bones or distal phalanges (deep group)
Nerve: tibial nerve
Blood supply: posterior tibial artery
Gastrocnemius
Superior muscle of posterior leg
prox: lateral head: lateral condyle of femur
Medial head: medial condyle of femur
Distal: calcaneal tendon
Innervation: tibial nerve
Action: plantar flexes the ankle when knee is extended, flexes leg at knee joint
Soleus
Superior muscle of posterior leg
Prox: soleal line and proximal tibia
Distal: calcaneal tendon
Innervation: tibial nerve
Action: plantarflexes ankle
Plantaris
Superficial muscle of posterior leg
Prox: lateral side of distal femur
Distal: calcaneal tendon
Innervation: tibial nerve
Action: weak plantarflexion
Popliteus
Deep muscle of posterior leg
Prox: lateral epicondyle of femur
Distal: posterior surface of proximal tibia
Innervation: tibial nerve
Action: weakly flexes knee; unlocks extended knee
Flexor Hallucus Longus
Deep muscle of posterior leg
Prox: posterior surface of fibula
Distal: great toe
Innervation: tibial nerve
Action: flexes great toe; weakly plantarflexes ankle; supports medial longitudinal arch of foot
Flexor Digitorum Longus
deep muscle of posterior leg
prox: posterior surface of tibia
Distal: phalanges of toes 2-5
Innervation: tibial nerve
Action: flexes toes 2-5; plantarflexes ankle; supports longitudinal arch
Tibialis posterior
deep muscle of posterior leg
Prox: posterior surface of tibia and fibula
distal: plantar surface of several tarsal bones
Innervation: tibial nerve
Action: plantarflexes ankle; inverts foot
Tendons of deep muscles of posterior leg
TBD
Flexor Retinaculum
Long tendons and principle vessels and nerves from posterior compartment of the leg pass posterior to the medial malleolus, deep to flexor retinaculum to enter the sole of the foot
Cutaneous Nerves of the Leg
TBD
Posterior Tibial Artery
terminal branch of popliteal artery; supplies posterior compartment of leg; close to its origin it gives off the fibular artery; terminates distal to the flexor retinaculum by dividing into medial and lateral plantar arteries
Fibular Artery
Descends in the posterior compartment of the leg adjacent to the posterior intermuscular septum; besides supplying muscles of the posterior compartment, it has perforating branches that supply muscles of the lateral compartment of the leg
Palpating the Posterior Tibial Artery
Posterior to the medial malleolus
FootDrop
Injury to the common fibular nerve as a result of fractures off the neck of the fibular, or pressure from casts and splints. Sensory loss occurs down the anterior and lateral sides of leg and dorsum of foot and toes. The muscles of the anterior and lateral compartments are paralyzed
As a result: the antagonist muscles (plantar flexors and invertors) cause the foot to be plantar flexed (foot drop) and inverted
Intermittent Claudication
ischemia of the muscles of the calf
Cramp-like pain during exercise due to insufficient blood supply
Rest corrects oxygen deprivation
Shin Splints
Edema and pain in the area of the distal 2/3s of the tibia
Results from repetitive micro trauma of the tibialis anterior and small tears in the periosteum covering the body of the tibia
Muscles of the Dorsum of the Foot
Originate from the calcaneus
Insert into the digits
Action is extension
Nerve supply is the deep fibular nerve
Extensor Digitorum Brevis
Dorsum of foot
Prox: calcaneus
Distal: long extensor tendons of toes 2-4
Innervation: deep fibular nerve
Action: aids the extensor digitorum longus in extending the four lateral toes
Extensor hallicus brevis
Dorsum of the foot
Prox: calcaneus
Distal: phalanx of the great toe
Innervation: deep fibular nerve
Action: aids extensor hallicus longus in extending the great toe
Clinic: Extensor digitorum brevis
Gained popularity based on it’s reliability in covering lower extremity wounds. It’s small. However, it has a reliable vascular pedicle and when elevated as a flap can provide stable coverage of the distal foot and anterior, medial or lateral ankle. The muscle has also been harvested and utilized as a microvascular muscle transplant to prove coverage in open wounds. It’s particularly useful for reconstruction of the hand and fasciae areas, which suffer from reconstruction with tissue, which isn’t pliable or bulky enough
Dorsalis Pedis Artery
Anterior tibial artery continues on the Dorsum of the foot and is rename
Ends by dividing into arcuate and larger deep plantar artery
Artery can be palpated lateral to the extensor hallicus longus tendon
Palpating can be useful when assessing peripheral vascular disease
Nerve Supply to Skin of Dorsum of the foot
TBD