| |
synonyms:hip separation, total hip arthroplasty dislocation, periprosthetic hip dislocation
Hip Dislocation ICD-10
A- initial encounter
D- subsequent encounter
S- sequela
Hip Dislocation ICD-9
- 835.00(closed unspecified hip dislocation) 835.10(open unspecified
- 835.01(closed posterior) 835.11(open posterior)
- 835.02(closed obturator) 835.12(open obturator)
- 835.03(closed other anterior) 835.13(open other anterior)
Hip Dislocation Etiology / Epidemiology / Natural History
- Generally associated with high energy trauma (MVA, fall from height), except when associated with prior THA.
- Posterior dislocations generally result if the leg is flexed and adducted at time of impact (dashboard injury).
- Anterior dislocations result from forceful adduction and external rotation.
- Associated with football, rugby, wrestling.
- Dislocation following total hip arthroplasty is twice as common in women than in men. It is more likely to occur in older patients.
Hip Dislocation Anatomy
- Lateral epiphyseal artery, which is the terminal branch of the medial femoral circumflex artery of the profunda femoris circulation supplies the majority of the femoral head.(Trueta, JBJS 35B:442;1953).
- Blood supply to femoral neck=extracapsilar arterial ring at base of neck supplied by branches of lateral and medial femoral circumflex artery, ascending cervical branches of arterial ring on surface of the neck, arteries of the ligamentum teres.
Hip Dislocation Clinical Evaluation
- ATLS resuscitation. These can be high enegery injuries, assessment should begin with the A,B,C's.
- Posterior dislocation: present with leg flexed, adducted and internally rotated.
- Anterior dislocation: present with leg flexed, abducted and externally rotated.
- Document neurovascular exam before and after reduction.
- Knee ligamentous exam indicated after reduction.
Hip Dislocation Xray / Diagnositc Tests
- A/P pelvis, A/P and lateral of affected hip and femur. Consider inlet, outlet and Judetviews if acetabular or pelvic ring injury is suspected.
- CT scan: assess for posterior pelvic ring injury, femoral head fracture, intra-articular fragments, impaction, acetabular fracture.
- MRI: indicated for patients with hip pain 3 months after hip dislocation to evaluated for osteonecrosis.
Hip Dislocation Classification / Treatment
- Hip Dislocation Reduction CPT Codes
- Posterior(90%): reduced with traction applied to the flexed, adducted and gently internally rotated hip with muscle relaxation/sedation and pelvic stabilization. Post reduction neuro exam and CT indicated. Open reduction via Kocher-Langenbeck approach indicated if closed reduction is unsuccessful. Consider femoral skeletal traction if large posterior wall fractures prevents maintenance of reduction.
- Anterior(10%): reduced with traction while extending and internally rotating the hip with muscle relaxation/sedation and pelvic stabilization. Post reduction neuro exam and CT indicated. Open reduction via anterior approach indicated if closed reduction is unsuccessful.
- Pediatric: epiphyseal separation during redcution has been rported in children >11yrs old. Reduction should be done within 6 hours under anesthesia with fluorscopic evaluation. IF physeal widening is apparent during reduction, cannulated screws fixation of the the femoral head should be performed before reduction.
- Periprosthetic hip dislocation: posterior approach total hip dislocation generally dislocates posteriorly (ensure cup is anteverted). Anterior approach total hip arthroplasty dislocation generally dislocates anteriorly (ensure cup is not too anteverted)
- Total hip arthroplasty dislocation First-time early dislocation with no component malalignment: closed reduction with education about dislocation precautions. Hip orthoses are of questionable benefit unless patient has cognitively impairment.
- Total hip arthroplasty recurrent dislocation or component malalignment: revision THA. (Patel PD, J Arthroplasty 2007:22(4Suppl):86-90)
Hip Dislocation Associated Injuries / Differential Diagnosis
- Sciatic nerve palsy (@15%)
- Acetabular fracture
- Pelvic ring injury
- Femoral head fracture
- Femoral neck fracture
- Femoral shaft fracture
- PCL tear
- Knee dislocation
- Osteonecrosis
- Vascular injury (external iliac or femoral vessel injury with anterior dislocations.
- Hip Arthritis
Hip Dislocation Complications
- Osteonecrosis: generally occurs within one year of injury, but has been reported up to 6yrs after injury.
- Neurologic injury
- Pain
- Loss of reduction
- Gait disturbance
- DVT / PE (Borer DS, JOT 2005;19:92).
- Heterotopic ossification:
Hip Dislocation Follow-up Care
- Posterior: avoid hip flexion, <90°, internal rotation and adduction.
- Anterior: avoid external rotation
Hip Dislocation Review References
- Rockwood and Greens
- Tornetta et al., Hip dislocation: current treatment regimens. J Am Acad Orthop Surg 1007; 5:27-36
|
