HIPS Flashcards
Articulating surfaces of the hip?
Head of femur
Acetabulum of the pelvis - has an acetabular labrum
Both covered in articualr cartilage
Intracapsular ligaments of the hip?
Ligament of head of femur
Extracapsular ligaments of the hip?
Anterior:
Iliofemoral ligament
Pubofemoral ligament
Posterior:
Ischiofemoral ligament
What is the ligament of head of femur? What does it contain?
It runs from the acetabular fossa to the fovea of the femur
It encloses a branch of the obturator artery
Where is the iliofemoral ligament found?
Arises from the anterior, inferior iliac spine and then bifurcates before inserting into the intertrochanteric line of the femur
Where is the pubofemoral ligament found?
Runs between the superior pubic rami and the intertrochanteric line of the femur anteriorly
Where is the ischiofemoral ligament found?
Runs between the body of the ischium and the greater trochanter of the femur posteriorly
Function of the iliofemoral ligament?
Prevents hyper extension of the hip joint
Function of the pubofemoral ligament?
Prevents excessive abduction and extension of the hip joint
Function of the ischiofemoral ligament?
Prevents hyper extension and holds the femoral head in the acetabulum
Arterial supply to the hip joint?
Medial and lateral circumflex femoral arteries that anatstamose at the base of the femoral neck to form a ring
The medial circumflex artery is repsonsible for the majority of the arterial supply
The artery to the head of femur and superior/infeiror gluteal arteries also provide some additional supply
Which nerves innervate the hip?
Sciatic, femoral and obturator nerves
Why can pain in the hip be referred to the knee?
As the sciatic femoral and obturator nerves supply both the hip and the knee
Stabilising factors for the hip?
Acetbulum is deep and encompasses nearly all of the head of femur
Acetabular labrum increases the depth and provides a larger articular surface
Iliofemoral, pubofemoral and ischiofemoral ligaments - have a unique spiral orientation which causes them to become tighter when the joint is extended
What movements can the hip do?
Flx/ext
Abd/add
Lateral and material rotation
Which muscles help carry out hip flexion?
Iliopsoas, rectus femoris, sartorius and pectineus
Which muscles help carry out hip extension?
Gluteus maximus
Hamstrings (Semimembranous, Semitendinous, Biceps femoris)
Which muscles help carry out hip abduction?
Gluteus medius and minimus
Piriformis
Tensor fascia latae
Which muscles help carry out hip adduction?
Adductor longus, brevis and Magnus
Pectineus
Gracilis
What does the degree to which flexion at the hip can occur depend on?
Whether the knee is flexed or not
When the knee is flexed, the hamstrings muscles are relaxed and the range of flexion is increased
What causes hip dislocations?
Trauma mostly - RTAs and significant falls from height
Can be a complication of total hip replacements
Congenital hip dislocations can be a cause - spectrum of DDH
What % of all hip dislocations do posterior dislocations account for?
90%
Position of leg following a posterior hip dislocation?
Affected leg is shortened, adducted and internally rotated
Position of leg following a anterior hip dislocation?
Leg is abducted and externally rotated
Types of hip dislocation?
Posterior
Anterior
Central
Clinical presentation of any hip dislocation?
Significant clunk/popping followed instantly by severe pain
Physical deformity
Inability to walk from pain
May be possible neurovascular injury
What is an important complication of posterior hip dislocations?
Sciatic nerve injury - in 10-20%
This is because the sciatic nerve runs posteriorly in the hip joint
Management of hip dislocations?
ABCDE approach
Analgesia
Reduction under GA within 4 hours
XR of hip following reduction
PT long term to strengthen surrounding g muscles
Why must reduction of a hip dislocation be done within 4 hours?
To reduce the risk of a vascular necrosis
Complications of hip dislocations?
Sciatic or femoral nerve injury
Avascular necrosis
Osteoarthritis: more common in older patients.
Recurrent dislocation: due to damage of supporting ligaments
Prognosis of hip dislocations?
2-3 months for hip to heal
Prognosis is best when the hip is reduced <12 hours post-injury and when there is less damage to the joint
What is avascular necrosis of the hip?
A type of osteonecrosis
Death of bone tissue secondary to loss of the blood supply which leads to bone destruction and loss of joint function
Possible causes of avascular necrosis of the femoral head?
Trauma - hip dislocations or fractures
Alcohol excess - can decrease blood supply to the bone
Chemotherapy
Long-term steroid use
Presentation of avascular necrosis of the hip?
initially asymptomatic
pain in the hip that may radiate to the groin or thigh. Aggravated by walking/climbing stairs and alleviated by rest.