Lecture 14: The Lower Extremity Flashcards
Joints in the lower extremity
Hip
Knee
Ankle
Hip
articulation btwn head of proximal femur and acetabulum of pelvis
acetabulum is deep socket = great amount of bony constraint
possesses large ROM in all three planes
- ONLY ROTATION/NO TRANSLATION
Hip vs shoulder
Hip is less mobile than shoulder b/c ilium doesn’t move around like scapula
Pressure in hips
There is a slight negative pressure in hips = suction femoral head in
Old people can feel discomfort/pain when a storm is coming
Hip ligaments
Ligamentum teres: WITHIN socket
Acetabular labrum: surrounding the socket to make it DEEPER
Iliofemoral (Y): outside the socket (anterior)
Pubofemoral: on anterior side
Ischiofemoral: on posterior side
Iliofemoral ligament
Y ligament
Stops excessive hip EXTENSION
From ilium to femur
Ischiofemoral ligament
Stops excessive hip FLEXION
Has slack = loose until a certain point
- higher ROM with flexion than extension w/ hip (b/c of this slack)
Stabilizing during walking
Done through hip ABductors (gluteus minimus and gluteus medius)
Iliotibial Band
Long band of connective tissues that hip ABductors attach to
Attaches to fibula below the knee jt.
Iliotibial Band Syndrome
Pain usually at lateral knee
Likely due to overuse of hip abductors
Usually pain is slightly delayed (around 3K of a 5K race)
The Knee
Articulation btwn distal femur and proximal tibia
Motion is restricted to FLEXION + EXTENSION in the sagittal plane (about ML axis)
Knee Ligaments
Collateral ligaments - LCL and MCL
Cruciate ligaments - ACL and PCL
Oblique popliteal ligament
Collateral ligaments
stop ROTATION of knee in FRONTAL plane
LCL and MCL
Cruciate ligaments
stop FORWARD/BACKWARD TRANSLATION of knee
No lever arm in flexion/extension
Cross over in middle @ axis of rotation
Oblique popliteal ligament
stops TORSION of the knee in TRANSVERSE plane
stops tibia from externally rotating on femur
