Download Hip Dislocation

Hip Dislocation
Anatomy
Synovial ball/socket; head = 2/3 sphere; capsule strong anteriorly
Ligaments: supported by iliofemoral, pubofemoral, ischifemoral ligament, ligament of head of femur and
transverse ligament of acetabulum
Blood supply: ascending branches of medial and lateral circumflex femoral arteries (from profunda
femoris); prone to disruption from fractures
acetabular branches of obturator and medial circumflex
branches of inferior and superior gluteal
Femoral head supplied by reticular anastomosis from medial and lateral circumflex, and artery of head
of femur (runs with ligament of head and enters at fovea; more important in children)
Epiphyses: Body:
appears 7/40
all disappear at 18-20yrs
Lower end:
appears birth
Head:
appears 6-12/12
Greater trochanter: appears 4yrs
Lesser trochanter:
appears 8yrs
Epidemiology
MOI
Examination
Posterior
Dislocation
In prosthesis: 70% in 1st month; due to XS flexion, adduction and internal rotation
Native: trauma (associated with sciatic nerve injury in 10-15%, fracture of femoral
head in 5%); sciatic nerve injury may be due to acetabular rim fracture
Forced applied to flexed knee posteriorly
Short, adducted, internally rotated
Likely irreducible fracture/dislocation if knee slightly flexed and hip in neutral
position
Complications
10% avascular necrosis (more if longer time dislocated)
50% acetabular / femoral fracture
10% sciatic nerve injury
Management
Urgent if native (within 6hrs); bed rest after for few days if 1 st, otherwise early
mobilisation if recurrent
Allis manouevre: stand on bed; hold down pelvis; hip and knee flex 90°; correct
adduction and internal rotation; grasp ankle between knees to provide fulcrum;
axial traction with rocking motion; can add lateral traction to proximal femur
Stimson: lie prone; leg hang over side of bed; 90° flexion as above; push down on
calf and bum; better if femoral fracture
Bigelow: flex (with your forearm under knee as fulcrum to provide upward traction)
 abduct  externally rotate  extend  internally rotate to neutral
Reverse Bigelow: quick jerk to slightly flexed thigh
Whister: elbow beneath affected knee, hand on unaffected knee; hold affected
ankle; push up with arm
Epidemiology
Usually MVA (forced abducation)
Classification
Type I: superior/pelvic, hip extended at time of injury
Type II: inferior/obturator, hip flexed at time of injury
Hip abducted and externally rotated at time of injury in both
Examination
Abducted, externally rotated, flexed
Can palpate femoral head anteriorly
80-90%
Anterior
Dislocation
10%
Complications
Femoral artery and femoral nerve injury
Management
Orthopaedic emergency; do within 6hrs to avoid avascular necrosis; reduced under
GA; in-line traction with hip and knee flexion to 90° and internal rotation
Central fracture
/ dislocation
Obturator
Dislocation
Through acetabulum; needs reduction under GA
Head over obturator foramen
Short, abducted and externally rotated
Needs reduction under GA