Hip Complex Flashcards
Hip Joint
Coxofemoral Joint
OR
Femoroacetabular Joint
Hip does what
Support weight of head, arms, trunk (HAT)
Structured primarily to serve weightbearing function
Hip joint articulation
Acetabulum of pelvis
AND
Head of femur
Hip Joint Classification
Diarthrodial
Synovial
Ball-and-Socket
3 DOF
Hip Osteokinematics
Flexion/Extension
Abduction/Adduction
Medial(IR)/Lateral(ER) rotation
Hip Open-packed Position
30 deg Flexion, 30 deg ABd, slight ER
Hip Closed-packed Position
Max extension, slight ABd, IR
Proximal Joint structure:
Pelvis 3 Bones
Ilium (2/5ths)
Ischium (2/5ths)
Pubis (1/5th)
All contribute/create to acetabulum
Full ossification of the pelvis happens between what ages?
20-25 years
Proximal Joint structure:
Acetabulum
Lunate surface
Acetabuluar notch
Acetabular fossa
Proximal:
Lunate surface
Horseshoe-shaped
Covered in a hyaline cartilage
Only to articulate with head of femur
Allows contact stress to be evenly distributed
Proximal:
Acetabular notch
Inferior aspect of the lunate surface
Transverse acetabular ligament-fibrous band connecting 2 inferior ends of lunate surface
Creates a fibro-osseous tunnel to acetabular fossa (fibroelastic fat covered with synovial membrane)
Proximal:
Acetabular fossa
Deepest aspect
Does NOT articulate with femoral head
Proximal:
Normal orientation of acetabulum
Faces lateral, inferior, slightly anterior*
Proximal:
Center edge angle of the acetabulum
Measures depth of acetabulum in the frontal plane
Normal: 25-40 degrees
Proximal:
Acetabular Dysplasia
<25 degrees
Abnormally shallow acetabulum
Lack of coverage of femoral head
Can lead to:
-Instability of the hip
-Increased loading of superior acetabular rim
Proximal:
Coxa Profunda/Acetabular Protrusio
> 40 degrees
Acetabulum excessively covers the femoral head
Can lead to:
-Mechanical ROM restriction
-Impingement between femoral head-neck junction and acetabulum
Proximal:
Anteversion
Acetabulum is positioned anteriorly in the transverse plane
More anteversion or less inclination:
Instability
Proximal:
Retroversion
Acetabulum is positioned posteriorly in the transverse plane
Distal:
More retroversion or more inclination:
Over coverage and impingement between acetabulum femoral head-neck junction
What does all of the acetabular abnormalities lead to?
Pathologies, including excessive cartilage wear and osteoarthritis
Proximal:
Acetabular Labrum
Wedge-shaped fibrocartilage ring
Attached to outer periphery of acetabulum by calcified cartilage
Nerve endings present:
-Proprioception (enhance stability)
-Pain (source/signal)
Transverse Acetabular Ligament
What happens when the labrum is compromised?
Friction stresses increases, deterioration of articular cartilage of hip joint =osteoarthritis
Proximal:
Functions of the acetabular labrum
Deepens socket
Increases concavity = femur head+acetabulum
Acts as a seal = stability
An abnormal shallow acetabulum increases what?
Stress on the surrounding capsule and labrum
Proximal:
Transverse Acetabular Ligament
A continuation of the acetabulum labrum
Serves as a tension band between anteroinferior and posteroinferior aspects of acetabulum
Protects blood vessels that travel beneath it
Acetabular labral tears are increasingly recognized as a source of:
hip pain and as a starting point for degenerative changes at the acetabular rim
What are some of the potential symptoms of a torn labrum?
anterior groin pain, clicking, locking, catching, instability, giving way, or joint stiffness
Distal Joint structure:
Femur
Head of femur
Neck of femur
Shaft of femur
Distal:
Head of femur
Covered in hyaline cartilage
2/3 of a sphere
Fovea- roughened pit serves as attachment site for ligamentum teres
Ligamentum teres-ligament of the head of the femur
T/F The radius of curvature of the femoral head is smaller in women than in men in comparison with the dimensions of the pelvis
True
Distal:
Neck of femur
Angulated so that the femoral head faces medially, superiorly, and anteriorly
Distal:
Angle of Inclination
Frontal plane
Between axis through femoral head & neck and longitudinal axis of femoral shaft
Normal: 125 degrees
T/F Women have a larger angle of inclination than men.
False; the angle of inclination is somewhat smaller than it is in men, owing to the greater width of the female pelvis.