Leg & Knee Joint Flashcards


























































______ - attachment site of the anterior cruciate ligament on the superior head of the tiba
Anterior intercondylar area
_____ -attachment site of the posterior cruciate ligament on the superior side of the tibia
Posterior intercondylar area
nLargest synovial joint in the body; weak mechanical joint
knee joint
knee joint has a strong fibrous capsule that is strengthened and supported by several external ligaments… the two most important are the
- Lateral (Fibular) collateral ligament (LCL)
- Medial (Tibial) collateral ligament (MCL)
___ and ____ join the femur and tibia and provide knee stability
- Anterior Cruciate ligament (ACL)
- Posterior Cruciate ligament (PCL)
____ is slightly relaxed when knee is flexed- tight when the knee is fully extended
Anterior Cruciate (ACL)
ACL prevents the femur from …. and the ACL prevents posterior/anterior displacement of the tibia
sliding posterior on the tibia and helps prevent knee hyperextension; anterior
ACL ruptures are quite common (10X more common than PCL ruptures) typically occur in sports related injuries when the knee is ____ and ___
extended and over-rotated
“unhappy triad”
ACL injuries occur in conjunction with tears of the medial meniscus and the MCL
Disruption of the ACL allows the tibia to be manually displaced anteriorly on the femur- referred to as the ____
“anterior drawer sign”
Posterior Cruciate (PCL)- tightens during knee
flexion
PCL prevents the femur from sliding anterior/posterior on the tibia and prevents anterior/posterior displacement of the tibia
anterior/posterior
Crescent shaped fibrocartilagenous plates on the superior articular surface of the tibia
Act like shock absorbers and help deepen the joint cavity
Commonly injured during torsional (twisting) knee injuries
Menisci of the Knee Joint
why are the mensci difficult to heal?
Menisci have limited blood supply and heal poorly when injured- often require surgical repair/removal of injured region
which mensci is more mobile, smaller and nearly circular?
lateral meniscus
Common fibular nerve divides into two branches:
- Superficial fibular nerve which innervates the lateral compartment of the leg
- Deep fibular nerve which innervates the anterior compartment muscles
Anterior compartment- all muscles are innervated by the ____
deep fibular nerve
Lateral compartment- all muscles are innervated by the ______
superficial fibular nerve
Two Posterior compartments (superficial and a deep)- all muscles are innervated by _____
tibial nerve
how many compartments are there in the lower leg?
4 lateral, anterior, deep and superficial posterior
superficial posterior group muscles and function
- gastrocnemius
- soleus
- plantaris
plantarflexors of the ankle joint (move down)
gastrocnemius and soleus muscle fibers?
soleus - slow red oxidative
gastronemius- fast white tiwch muscles
tibial nerve roots
S1 and S2
deep posterior group muscles and function
- popliteus
- flexor hallucis longus
- flexor digitoum longus
- tibialis posterior
plantarflex the ankle
flex the toes
invert the foot
Tendons of these 3 muscles (Tibialis posterior, flexor Digitorium longus, and flexor hallucis longus) pass into the foot via the ____
tarsal tunnel
____ enters the foot via the tarsal tunnel and terminates as the medial & lateral plantar nerves in the foot
Tibial nerve
Popliteal artery gives rise to several _____ which vascularize the knee joint
genicular arteries
components of Tarsal Tunnel medial to lateral
Tibialis Posterior Tendon
Flexor Digitorum Longus Tendon
Posterior Tibial Artery and Tibial Nerve
Flexor Hallucis Longus
Common Fibular
Nerve divides into
- Superficial fibular nerve-innervates lateral compartment…then sensory to dorsum of the foot
- Deep fibular nerve- innervates anterior compartment…then sensory between big toe and 2nd toe
Superficial fibular nerve-innervates
lateral compartment…then sensory to dorsum of the foot

Deep fibular nerve- innervates
anterior compartment…then sensory between big toe and 2nd toe

lateral compartment muscles and function
fibularis longus and fibularis brevis
evertors of the foot
____ its tendon passes through the groove in the cuboid and inserts into the medial cuneiform and 1st metatarsal base
Fibularis longus muscle
____ its tendon inserts into the base of the 5th metatarsal
Fibularis brevis muscle
roots of superfical fibular nerve
nBoth innervated by L5 & S1 of the superficial fibular nerve
anterior compartment muscles and function
dorsiflexors “toes to the sky”
- tibialis anterior
- extensor digitorum longus
- extensor hallucis longus
- fibularis tertius
_____- extends the hallux (big toe)
Extensor hallucis longus
______ extends digits (inserts into extensor expansion on toes)
Extensor digitorum longus
deep fibular nerve roots
L4, L5 & S1
Drop foot occurs when muscles in the ____ compartment of the leg become weakened or paralyzed
anterior
This condition can result from trauma or injury to the common fibular nerve or the deep fibular nerve or (disc herniation that affects L4/L5 nerve roots)
These patients compensate with a “steppage gait”- hyperflexion of the hip to raise the foot/leg during the swing phase of gait
drop foot
Diminished pulses can often times indicate
nocclusive vascular disease in more proximal vessels (popliteal, femoral, iliac)
or
Anterior compartment syndrome occurs when swelling (from trauma, overuse) compresses neurovascular structures within the compartment causing:
diminished or absent dorsalis pedis pulse
pain
Extreme pain of the anterior compartment muscles
Hinge type synovial join
ankle joint
Trochlea of talus is wider anteriorly/posteriorly
Hence-ankle is more stable in a dorsiflexed/plantarflexed position vs. a dorsiflexed/plantarflexed position
anteriorly; dorsiflexed than plantarflexed
the most important ligament Strengthening the lateral aspect of the joint- stabilize ankle during inversion
Anterior Talofibular
Stronger than the lateral ligaments
All arise from the medial malleolus
Stabilize ankle during eversion
deltoid ligaments
___ most commonly injured ankle ligament
Anterior Talofibular ligament
____ is easily damaged as it winds about the head of the fibula
Common fibular nerve
____ can compress underlying neurovasculature
Compartment syndromes



