Hip Questions

Question 1

Leg Length Shortening - Apparent

Answer 1

Due to pelvic tilting:
Fixed flexion deformity of hip
Fixed ADduction deformity of the hip (OA)

Question 2

Leg Length Shortening - True

Answer 2

Due to joint or bony abnormality:
Pathology distal to trochanters: previous # femur, previous # tibia, growth disturbance (polio, epiphyseal trauma)
Pathology proximal to trochanters: #NOF, OA, hip dislocation

Question 3

THR

Answer 3

Indications: OA, less commonly RA / DDH / seronegative arthropathy, displaced intracapsular # NOF in young patients

Complications: peri-operative, acute dislocation, chronic infection

Contraindications: mild disease, doubt as to origin of hip pain, morbid obesity

Question 4

Blood supply to the femoral head

Answer 4

1. Cervical arteries running in the joint capsule retinaculum (main supply)
2. Intramedullary vessels in the femoral neck
3. Vessels of the ligamentum teres (negligible contribution, often non existent)

Question 5

Displaced intracapsular # NOF

Answer 5

Inevitable interruption of intramedullary vessels and likely disruption of cervical arteries

High risk of avascular necrosis (AVN) of femoral head

Usually treated by hip replacement:
Hemi-arthroplasty in older patients
THR in younger patients likely to be more active post-op

Question 6

Undisplaced intracapsular # NOF

Answer 6

Inevitable interruption of intramedullary vessels, possible disruption to cervical arteries

Moderate risk of AVN

Usually pinned in the hope that AVN will not develop

Question 7

Intertrochanteric or subtrochanteric extracapsular # NOF

Answer 7

Little interruption to blood supply of femoral head
Low risk of AVN
Usually stabilised and reduced using DHS

Question 8

Hip ABductors

Answer 8

Gluteus medius & minimus