Lower leg Flashcards
The lower leg is divided into compartments, formed via
the anterior and posterior intermuscular septa.
The compartments formed:
Anterior
Posterior
Lateral
Anterior compartment also called
extensor compartment
Anterior compartment located
anterior to interosseous membrane
Inferiorly
retinaculum found just above the ankle joint
- Superior extensor retinaculum
2. Inferior extensor retinaculum
Muscles of the anterior compartment:
[Extensors] Tibialis anterior Extensor digitorium longus Extensor halucis longus Fibularis tertius
Anterior compartment artery and vein
Anterior tibial
Anterior tibial becomes
the dorsalis pedis in the foot
Anterior compartment all supplied by
Deep fibular nerve
Tibialis anterior
Tibialis anterior proximal attachment
Lateral condyle and superior half of lateral surface of tibia
interosseous membrane
(upper 2/3 of the latreral surface of the tibia)
Tibialis anterior distal attachment
Medial ant inferior surface of medial cuneiform and base of 1st metatarsal
Tibialis anterior nerve
Deep fibular nerve
Tibialis anterior action
Dorsiflexes ankle and inverts foot
Extensor digitorium longus
Extensor digitorium longus nerve supply
Deep fibular nerve
Extensor digitorium longus proximal attachment
Lateral condyle of the tibia
head of the fibula
upper2/3 of the anterior surface of the fibula
Extensor digitorium longus distal attachment
Tops of the middle and distal phalanges of the lesser toes
Extensor digitorium longus action
- Extension of the 4 lesser toes at the metatarsophalangeal,proximal and distal intephalangeal joints.
- Dorsiflexion of the ankle
- Eversion of the foot
Extensor hallucis longus
Extensor hallucis longus nerve supply
Deep fibular nerve
Extensor hallucis longus proximal attachment
Middle 2/3 of the medial surface of the anterior fibula
Extensor hallucis longus distal attachment
Base of the distal phalanx of the great toe
Extensor hallucis longus action
- Dorsiflexion of the ankle
- Extension of the great toe at the metatrsophalangeal and interphalangeal joints
- Weak inversion of the foot
Lateral compartment
Also called the averter compartment
Lateral compartment muscles
Fibularis longus
Fibularis brevis
Lateral compartment muscles
Fibularis longus
Fibularis Brevis
Share what?
Nerve supply: Superficial fibular
Action:Eversion of the foot, Plantar flexion of the ankle
Lateral compartment arteries
Branches of anterior tibial
Branches of fibular
Fibularis longus
Fibularis longus nerve supply
Superficial fibular
Fibularis longus proximal attachment
Head and upper 2/3 of the lateral surface of the fibula
Fibularis longus distal attachment
Undersurfaces of the medial cuneiform and 1st metatarsal bones
Fibularis longus action
Action
Eversion of the foot
Plantar flexion of the ankle
Fibularis brevis
Fibularis brevis nerve supply
Superficial fibular
Fibularis brevis proximal attachment
Lower 2/3 of the lateral surface of the fibula
Fibularis brevis distal attachment
Tuberosity of the 5th metatarsal bone
Fibularis brevis action
Eversion of the foot
Plantar flexion of the ankle
Posterior compartment
Also called the plantar flexor compartment
- Largest compartment
- Also contains flexor retinaculum
Posterior compartment Superficial group
- Gastrocnemius
- Soleus
- Plantaris
- Gastrocnemius
Gastrocnemius and Soleus
Triceps surae
Gastrocnemius and soleus
calcaneal tendon
Posterior compartment deep group
Popliteus
Flexor digitorium longus
Flexor hallucis longus
Tibialis posterior
All posterior muscles (flexors) supplied by the same nerve
tibial nerve
Gastrocnemius
Gastrocnemius proximal attachment
Medial head: posterior surface of the medial femoral condyle
Lateral head: posterior surface of the lateral condyle
Gastrocnemius distal attachment
Posterior surface of the calcaneus
Gastrocnemius action
Plantar flexion of the ankle
Flexion of the knee
Gastrocnemius nerve supply
Tibial n
Soleus
Soleus proximal attachment
- Posterior surface of the proximal fibula
- proximal 2/3 of the posterior tibial surface
Soleus distal attachment
Posterior surface of the calcaneus
Soleus action
Plantar flexion of the ankle
Soleus nerve supply
Tibial n
Plantaris
Plantaris proximal attachment
Lateral supracondylar ridge of the femur above lateral head of gastrocnemius
Plantaris distal attachment
Calcaneus tendon
Plantaris action
Weakly plantar flexion of the ankle joint
Flexion of the knee joint
Plantaris nerve supply
Tibial nerve
Popliteus
Popliteus proximal attachment
Posterior surface of lateral condyle of the femur
Popliteus distal attachment
Upper posterior medial surface of tibia
Popliteus action
- Internal rotation of the knee as it flexes
- flexion of the knee
Popliteus nerve supply
Tibial nerve
Flexor digitorium longus
Flexor digitorium longus proximal attachment
Middle 1/3 of the posterior surface of the tibia
Flexor digitorium longus distal attachment
Base of the distal phalanx of toes 2-5
Flexor digitorium longus action
Flexion of toes 2-5 at the metatarsophalangeal, proximal and distal interphalangeal joints.
Plantar flexion of the ankle
Inversion of the foot
Flexor digitorium longus nerve supply
Tibial nerve
Flexor hallucis longus
Flexor hallucis longus nerve supply
Tibial nerve
Flexor hallucis longus proximal attachment
Middle 2/3 of the posterior surface of the fibula
Flexor hallucis longus distal attachment
Base of the distal phalanx of the big toe plantar surface
Flexor hallucis longus action
Flexion of the graet toe at the metatarsophalangeal and interphalangeal joints.
Plantar flexion of the ankle
Inversion of the foot
Tibialis posterior
Tibialis posterior proximal attachment
Posterior surface of the upper ½ of the interosseous membrane and adjacent surface of the tibia and fibula
Tibialis posterior distal attachment
Lower inner surface of the navicular and cuneiform bones and bases of the 2-5 metatarsal bones
Tibialis posterior action
Plantar flexion of the ankle
Inversion of the foot
Tibialis posterior nerve supply
Tibial nerve
Achilles tendon
Achilles tendon is formed by
the tendons of gastrocnemius and soleus muscles
Nerves that run through the Posterior compartment
- Tibial
- Medial sural cutaneous
- Common fibular
Arteries that run through the Posterior compartment
- Posterior tibial
- Fibular
- Circumflex fibular
posterior tibial Artery and tibial Nerve location and muscles
near medial malleolus (tibia)
- Tibialis posterior
- flexor Digitorium longus
- flexor Hallucis longus
Tibial nerve and _____ runs together in the lower leg
posterior tibial artery
Veins in the lower leg
- Long saphenous vein
- short saphenous vein
where is the popliteal fossa found?
Posterior of the knee
Boundaries of the popliteal fossa
Knee joint
- Largest and very complex
- Combined function of weight-bearing and
locomotion
>considerable stress and strain on joint - Powerful extensor and flexor muscles as
well as powerful ligaments
Bones that form part of the knee joint
- Femur
- Tibia - carry more weight than the fibula
- Fibula - serves as attachment for
important joint structures
Patella - function: creating an improved
angle of pull for the quadriceps
muscle group and patellar tendon
Bony landmarks to know:
- superior and inferior poles of the
patella- tibial tuberosity
- Medial and lateral femoral condyles
- Upper anterior medial surface of the
tibia - Head of the fibula
- Meniscus in the joint
- enhancing stability
Medial meniscus for medial femoral
condyle
Lateral meniscus for lateral femoral
condyle
What type of joint is the knee joint?
Synovial - Hinge joint
Important ligaments of the knee joint
- provide static stability
- Anterior and posterior cruciate
ligaments:
maintain the anterior (ACL) and posterior (PCL) ligaments– stability of the joint and rotation stability - Medial side of knee:
tibial (medial) collateral ligament (MCL) - Lateral side of the knee:
fibular (lateral) collateral ligament (LCL) - Oblique popliteal ligament
- Arcuate popliteal ligament
+/- bursa in the knee joint
10
Knee joint movements
- flexion
- Extension
- External rotation
- Internal rotation
Primary knee extension muscles
Rectus femoris
Vastus medialis
Rectis lateralis
Vastus intermedius
Primary knee flexion muscles
Biceps femoris Semimembranosus Semitendinosos Sarrtorius Gracilis Popliteus Gastrocnemius
Nerves of the knee joint
Femoral n
Tibial division of the sciatic n
Fibularus (peroneal) n