Exam 2: Lower Extremity Handout Part 2
Card Set Information
Exam 2: Lower Extremity Handout Part 2
anatomy lower extremity
review of lower extremity handout for exam 2
What is the clinical importance of the plantaris muscle?
possibility of its rupture
What would cause the plantaris muscle to rupture?
Violent ankle movements
sudden dorsiflexion of ankle joint
In most cases of apparent rupture of the plantaris tendon, muscle fibers of which other muscle are also torn?
Injury to the plantaris muscle is common in which athletes?
How painful is the rupture of the plantaris tendon?
so severe that person is unable to bear weight on the foot
The long tendon of the plantaris muscle is common used in:
reconstructive surgery of the tendons f the hand
What is the affect of removing the plantaris tendon completely?
no disability of knee or ankle movements
What is the role of the plantaris muscle?
minor role in acting with the gastrocnemius
How is the tibial nerve protected?
because it is deep
Is the tibial nerve commonly injured?
What may damage the tibial nerve?
lacerations in popliteal fossa and posterior dislocations of knee joint
What happens when the tibial nerve is damaged?
paralysis of all muscles in posterior compartment of leg and intrinsic muscles in sole of foot
What happens when plantar flexors of foot are paralyzed from tibial nerve damage?
patient unable to curl toes or stand on them
What sensations are lost with damage to the tibial nerve?
sensation in sole of foot
Loss of sensation in the sole of the foot makes it vulnerable to the development of:
Absence of the posterior tibial artery with compensatory enlargement of which artery occurs in about 5% of people?
Where can the pulse of the posterior tibial artery be palpated?
halfway between posterior surface of medial malleolus and medial border of tendo calcaneus
condition caused by ischemia of leg muscles owing to arteriosclerotic stenosis of leg arteries
What characterizes intermittent claudication?
leg cramps that develop during walking and disappear soon after rest
What is palpatation of dorsalis pedis pulse essential for?
in suspected cases of intermittent claudication
Where can the dorsalis pedis pulse be felt?
on dorsum of foot, where artery passes over navicula and cuneiform bones just lateral to extensor hallucis longus tendon
distal to this at proximal end of first interosseous space
what does a diminished or absent dorsalis pedis pulse suggest?
Does failure to detect a dorsalis pedis pulse always indicate the presence of arteriosclerotic disease?
Fractures of femora neck close to femoral head often disrupt what?
blood supply to the head of femur
In some cases of a fractured femoral neck, what supplies the proximal fragment of the femoral head?
the artery in the ligament of the head
If the ligament of the head of the femur is ruptured what happens to the blood supply to the proximal fragment of the femoral head?
fragment of bone may receive no blood and undergo aseptic necrosis
What is aseptic necrosis?
death in absence of infection
What do the femoral, sciatic and obturator nerves supply?
knee and hip joint
Since the knee receives innervation from the same nerves as the hip, what might hip disease cause?
referred pain to the knee
Why might the sciatic nerve be injured during posterior dislocations or fracture-dislocations of the hip joint?
because of the close relationship of the sciatic nerve to the hip joint
If the sciatic nerve is injured from a hip injury, what might result?
paralysis of hamstring muscles and those muscles distal to knee supplied by branches of sciatic nerve
sensory changes in skin over posterior and lateral aspects of leg and over much of foot
How is the knee jerk reflex tested?
with leg flexed, patellar ligament struck
What is the normal response of knee jerk?
extension of leg
What would block the knee jerk reflex?
damage to femoral nerve
damage to reflex centers in spinal cord (L2-4)
What does the femoral nerve supply?
What do the tibial and fibular collateral ligaments prevent?
disruption of sides of knee joint
When are the tibial and fibular collateral ligaments tightly stretched?
when leg is extended
When leg is extended and the tibial and fibular collateral ligaments are stretched, what are they preventing?
rotation of tibia laterally or femur medially
When collateral ligaments are slack during flexion of leg, they permit what?
some rotation of tibia on femur
Which collateral ligament is least likely to be torn?
fibular collateral ligament
What could cause the fibular collateral ligament to tear?
severe blows to medial side of knee that force it laterally
Do lesions (sprains/tears) of the fibular collateral ligament have serious consequences?
Which part of the fibular collateral ligament usually tears?
What could happen to the head of the fibula when the distal end of the fibular collateral ligament tears?
head of fibula pulled off because ligament is stronger than bone
Complete tears offibular collateral ligament are often associated with stretching of which nerve?
common peroneal nerve
What happens if the common peroneal nerve is stretched?
affects mm of anterior and lateral compartments of leg
produce foot drop from paralysis of dorsiflexor and eversion of mm of the foot
The medial meniscus is firmly attached to what?
tibial collateral ligament
Injury to the tibial collateal ligament frequently results in concomitant injury to:
Rupture of tibial collateral ligament, associated with tearng of medial meniscus and ACL is common type of injury in which sport?
What causes an injury to the unhappy triad?
blow to lateral side of knee
What are the 3 C's that might be damaged in knee injuries?
Sprains of tibial collatera ligament result in:
tenderness over femoral or tibial attachments of this ligament, owing to tearing of these parts
friction bursitis caused by friction between skin and patella
If the inflammation from prepatellar bursitis is chronic what happens to the bursa?
becomes distended with fluid and forms soft, fluctuant swelling anterior to knee --commonly called "housemaid's knee"
What could cause the relatively weak ACL to be torn?
when tibial collateral ligament ruptures after knee is hit hard from lateral side while foot is fixed in the ground
tibia is driven anteriorly on femur
femur driven posterioly on tibia
knee joint is severely hyperextended
When the knee is hit hard from the lateral side while the foot is fixed, what is the first thing to happen?
tibial collateral ligament ruptures
When the tibial collateral ligament ruptures from a hard hit to the lateral side of the knee what does this do?
opens joint on medial side, may tear medial meniscus and ACL
What happens with an ACL tear?
knee jont becomes very unstable
How do you test the stability of the ACL?
tibia is pulled in an anterior direction
if anterior movement occurs, this indicates torn ACL