Hip Joint Flashcards
Classification of hip joint
Synovial ball and socket
How many axes does the hip joint have?
3
how many degrees of freedom does the hip joint have?
3
Articular surfaces of the hip joint
The head of the femur and the acetabulum of the innominate hip bone
what is the acetabulum?
Hemispherical hollow in the outer surface of the innominate bone
name the parts of the acetabulum
Lunate surface
Acetabular notch
Acetabular labrum
What is the lunate surface?
the articular surface of the acetabulum
what is the shape of the lunate surface and why?
an incomplete ring which is broadest at its upper part where the pressure of the body weight falls in the erect attitude.
What is the acetabular notch?
a notch in the rim of the acetabulum through which blood vessels and nerves pass
What is the acetabular labrum and its function?
a fibrocartilaginous rim which increases the depth of the acetabulum
Structure of the head of the femur
2/3rds of a sphere
covererd with articular cartilage apart from the fovea capitis
Is the hip joint congruent or incongruent and why?
Incongruent- there is limited contact between the arched acetabulum and the rounded femoral head
Describe the joint capsule of the hip
Strong dense sleeve
Thicker anteriorly & superiorly
Describe the attachment of the joint capsule of the hip
Attaches to the margin of the acetabulum
Surrounds the neck of the femur, along the interochrochanteric line to a line on the under surface of the neck by the lesser trochanter
What are the directions of the fibers in the joint capsule of the hip
Longitudinal, oblique, arcuate & zona orbicularis (circular round)
Name the 5 capsular ligaments of the hip joint
Iliofemoral, pubofemoral, ischiofemoral, transverse ligament of the acetabulum & ligamentum teres
Iliofemoral Ligament origin
Anterior inferior iliac spine (AIIS) of the innominate (hip) bone
Iliofemoral Ligament insertion
Intertrochanteric line of the femur
Iliofemoral Ligament limitation to movement
limits hip extension, adduction and lateral rotation.
Pubofemoral ligament origin
Iliopubic eminence and superior pubic ramus of the innominate bone
Pubofemoral ligament insertion
Lower part of the intertrochanteric line of the femur
Pubofemoral ligament limitation to movement
limits hip extension, abduction and lateral rotation.
Ischiofemoral ligament origin
Body of the ischium behind and below the acetabulum of the innominate bone
ischiofemoral ligament insertion
Superior part of the neck and root of the greater trochanter of the femur
Ischiofemoral ligament limitation to movement
limits hip extension, abduction and medial rotation.
Transverse Ligament of the Acetabulum origin
it goes across the deficient inferior acetabular rim of the innominate bone
Ligamentum teres origin
Margins of the Acetabular notch of the innominate bone
ligamnentum teres insertion
Fovea capitis on the head of the femur
Ligamentum teres limitation to movement
taut in flexion and adduction
What is the acetabular fat pad?
It is a fibroelastic fat pad and contains proprioceptive nerve endings.
Where is the acetabular fat pad located?
Within the acetabular fossa
Synovial membrane of the hip - what does it line & where does it extend to/from
It extends like a sleeve around the ligament of the head of femur, attaching to the margins of the fovea capitis. At the femoral attachment of the joint capsule, the synovial membrane is reflected up towards the head as far as the articular margin.
What determines the stability of the hip joint
the shape of the bones, the strong re-enforced capsule, the acetabular labrum and the muscles crossing the joint
What particularly ensure the stability of the hip?
The peri-articular muscles are essential, especially those which cross the joint transversely.
In which 5 way can the hip joint move?
flexion, extension, abduction, adduction & rotation
describe flexion of the hip joint
90 with SLR, active hip and knee flexion 120 passive hip and knee flexion 145.
All capsular ligaments are relaxed.
describe extension of the hip joint
with knee in extension 15 -20
with knee in flexion 10
Passive extension 20 - 30.
All capsular ligaments are taut.
describe abduction of the hip joint
abduction at one joint is automatically followed by a similar degree of abduction at the other joint, around 45.
Medial part of iliofemoral, Pubofemoral and Ischiofemoral ligaments taut.
describe adduction of the hip joint
no pure adduction, but combined movement of adduction and extension, around 45.
Lateral part of Iliofemoral taut and Ischiofemoral stretched
describe rotation of the hip joint
medial rotation 45
Iliofemoral and Pubofemoral slack, Ischiofemoral taut.
lateral rotation 45
Iliofemoral and Pubofemoral taut, Ischiofemoral slack.
