Station 4: The Hip and Pelvis Flashcards
What is normal Hip flexion ROM?
100-135 degrees
What are some reasons for variation in hip flexion ROM?
History of injury
Connective tissue tightness
Why do we measure hip flexion ROM with knee bent?
Removes hamstrings from measurement
What is normal Hip Hyperextension ROM?
10-30 degrees
How can you cheat a hip hyperextension ROM measurement?
Arch back
What does a narrow stance squat suggest about the acetabulum?
Shallow acetabulum
What does a wide stance squat suggest about the acetabulum?
More bone coverage of acetabulum
What two angles/structures relate to the angle of the acetabulum?
Centre-edge angle (Angle of Wiberg)
Acetabular anteversion angle
What two angles/structures relate to the angle of the femur?
Angle of inclination
Torsion Angle
What structures surround the acetabulum
Acetabulum labrum
Ligamentum teres
Transverse ligament
What is the optimal centre edge angle (angle of Wiberg)
35-40 degrees
What is the Centre-edge angle?
How much roof of the acetabulum is there over the femur (35-40 degs)
What plane is the centre edge angle in?
Frontal plane
What does a smaller centre edge angle mean?
It means there is less of a roof over the femur. This means you can see more into the socket
Less stability but more mobility. Greater risk of injury
What is the optimal acetabular anteversion angle?
20 degrees
What is the acetabular anteversion angle?
How much the acetabulum comes round the front of the femur (20 degs)
What plane is the acetabular anteversion angle in?
Transverse
What does a greater acetabular anteversion angle mean?
Less bone comes round the front of femur
Can see more into acetabulum socket
What is the optimal angle of inclination?
125 degrees
What is the angle of inclination?
The angle between the shaft and neck of the femur (125 degrees)
What are the different deformities from higher or lower than optimal angles of inclination?
Coxa vara (<125 degs)
Coxa valga (>125 degs)
What is Coxa Vara?
Coxa Vara is where the angle of inclination is <125 degrees. (More like a right angle R for right angle in vara). Femoral neck is flat and really stable but less mobile.
Lots of shear force through hip as a result
What is Coxa Valga?
Coxa Valga is where the angle of inclination is >125 degrees. Femoral neck is steep and really mobile but less stable.
Less shear force through hip as a result
Seen in people with cerebral palsy
What is the optimal torsion angle?
15 degrees
What is the torsion angle?
Orientation of neck and femur. It sits 15 degrees forward (anteversion)
What is retroversion?
Neck and femur sits <15 degrees forward. Sits straight into side or backwards
Feet twist out
What is excessive anteversion?
Neck sit excessively forward
Feet twist in to compensate (pigeon toe)
What is the acetabulum labrum made of and what does it do?
It is made of fibrocartilage and is horseshoe shaped, found in the socket (intrinsic)
Deepens socket, suctions head of femur into socket
Shock absorption and cushion for load bearing
What is the ligamentum teres?
Runs through inside of joint - connecting bone to bone
Fovea capitus into acetabulum
Either delivers blood flow and nerve supply OR is completely redundant
What is the transverse ligament?
Connects acetabulum at bottom of socket
Completes the rounded shape
Prevents inferior dislocation (uncommon)
What are the three ligaments of the hip and what do they do?
Iliofemoral
Pubofemoral
Ischiofemoral
All extrinsic and screw head of femur into socket
What is the thinnest hip ligament?
Ischiofemoral
The front hip ligaments are loosest in what motion?
Hip flexion
When do hip ligaments pull tightest?
Hip extension and Internal rotation
When do hip ligaments pull loosest?
Hip flexion and External rotation
What is true leg length discrepancy, what does it cause and how do you find it?
It is the actual difference in leg length
Causes tilt in pelvis and secondary compensation of spinal column
Find ASIS and medial malleolus and measure difference between two bony landmarks
What is apparent leg length discrepancy, what does it cause and how do you find it?
Determines whether leg length differences are due to pelvic rotation, sacroiliac dysfunction, foot pronation/supination or postural abnormalities
Find umbilicus and medial malleolus and measure difference between two bony landmarks
