Clinical Anatomy Considerations of the Lower Limbs Flashcards
What confers passive stability to the hip joint?
Bony architecture = femoral head and acetabulum, ball and socket
Acetabulum labrum = fibrocartilaginous rim along the margin of the acetabulum
Ligaments and muscles
How does a posterior hip dislocation typically occur?
During a traumatic event when the hip in a flexed, adducted and medially rotated position
What nerve can be affected by a posterior hip dislocation?
Sciatic nerve (L4-S3 anterior rami), most commonly the common fibular division
Where does the sciatic nerve run?
Leaves pelvis through greater sciatic foramen inferior to the piriformis, runs posterior to the acetabulum at the level of the ischium
What is Trendelenburg’s sign?
Inferior movement of the contralateral hip when standing on one leg, due to dysfunctional hip abduction caused by muscle weakness or paralysis
What muscles abduct the hip?
Gluteus medius = originates between the anterior and posterior gluteal lines of the ilium
Gluteus minimus = originates between the anterior and inferior gluteal lines of the ilium
Where do the gluteus medius and minimus insert onto?
The greater trochanter of the femur
Where does the superior gluteal nerve (L4-S1) run?
Leaves pelvic cavity via the greater sciatic foramen superior to the piriformis, passes between gluteus minimus and gluteus medius
What are some features of femoral shaft fractures?
Displaced by muscular contraction, causing rotation and/or shortening, sharp fragments may injure nearby structures
What is a maisonneure fracture?
Separating of the distal tibia and fibular can cause tearing of the tibiofibular syndemosis (e.g fracture to proximal fibular)
What are potential neural complications of a maisonneure fracture?
Anterior compartment = deep fibular nerve, dorsiflexion
Lateral compartment = superficial fibular nerve, eversion
Cutaneous innervation = superficial fibular nerve and deep fibular nerve
What causes foot drop?
Dysfunction of anterior compartment musculature
What are some features of foot drop?
May lead to changes in gait, high steppage and foot slap
What do active components of joint do?
Add to the movement of the joint (e.g muscle)
What does the labrum of the acetabulum do?
Stops bony edges grinding against the joint and keeps head of the femur in the joint
Why are ligaments at a joint in a spiral?
So they can contract when the joint moves to add to the stability
What is the classic position of the head of the femur in a hip dislocation?
Superior, lateral and posterior to the acetabulum
What can damage to the common fibular nerve cause?
Loss of movement in the foot
Do distal or middle femur features affect the blood supply more?
Distal = femoral artery runs anteriorly on femur before moving posteriorly
What are the menisci of the knee?
Wedge shaped cartilage = absorb shock and make joint more stable
What is varus posture?
Knees oppose each other, compression on medial side
What is valgus posture?
Knees touch each other, compression on lateral side
What happens if you spread the tibia and the fibular at the bottom?
They will break apart at the top
Lack of what action causes foot drop?
Inability to dorsiflex
