Wk 2: hip joint bones Flashcards
Hip Joint
connects lower limb to the trunk
Supports the entire bodys weight and stable transference of weight
Multiaxial, synovial and ball and socket
Features of the hip joint
- Articular surfaces
- Acetabular labrum
- Joint capsule
- Close packed position
Femur
upper leg
Acetabulum (innominate pelvis)
formed by union of three component parts
- Ilium (2/5)
- Ischium (2/5)
- Pubis (1/5)
Two areas of acetabulum
- Semilunar area covered with articular cartilage
- Acetabular fossa (non-articular area)
Acetabular notch (acetabulum)
- Inferior deficiency of the acetabulum
- Transverse ligament
Acetabular labrum
Fibrocartilage wedge attached to rim of acetabulum
Function: deepens socket and therefore increases stability
Acetabular fat pad
Located in the acetabular notch
Function: proprioception
Joint capsule
- Strong
- Thickest anteriorly and superiorly
Labrum -> intertrochanteric line
Synovial membrane
- Lines internal surface of capsule, covers labrum
- Cavity communicates with the psoas major bursa
Close packed position of the hip joint
- When articular surfaces have their MAXIMUM area of contact with each other
- Extension of hip
- Ligaments of the hip are taut (stability)
Ligaments of the hip joint
Capsular ligaments
Intracapsular ligaments
Capsular ligaments
Iliofemora
Pubofemoral
Ischiofemoral
Intracapsular ligaments
Transverse ligament
Ligamentum teres
Iliofemoral
- Located anteriorly (triangular in shape)
- Sometimes small deficiency anteriorly (covered by iliopsoas)
Inferior band: limits extension, and external rotation
Superior band: limits extension, adduction and external rotation
Pubofemoral
- Located inferiorly and anteriorly
Functions: limits abduction, extension and external rotation
Ischiofemoral
- Located posteriorly
- Least well defined
Functions: limits extension, abduction and internal rotation
Transverse ligament
- Completes acetabulum, breaches the acetabular notch
Ligamentum teres
- From transverse ligament to fovea capitis
- No strict mechanical function
- Proprioceptive role and a possible source of hip pain
Bursae around the hip types
Greater trochanteric bursae
Iliopectineal bursa
Greater trochanteric bursae
- Sits between the greater trochanter and the Iliotibial band
- Reduce friction between the muscle and bone
Iliopectineal bursa
Iliopsoas bursa
- Lies between the tendon of iliopsoas and the fibrous capsule of the hip
- Reduce friction between muscle and joint capsule
Factors that keep the hip joint stable
- Articular fit: reasonable congruence
- Acetabular labrum
- Strong capsule
- Functions of muscles: line of pull
- Bony factors (angle of inclination)