The Clinical Treatment And Progress Of Femoral Head Fractures With Posterior Hip Dislocations

Femoral head fractures with posterior hip dislocations are known as Pipkin fractures, which account for the morbility of 4%–17% of hip fracture-dislocations. The incidence of this injury is more common than before beacause of the development of transport. Due to the limited incidence of this injury, controversies remain on the optimal strategy of treatment. This review addresses many aspects of this injury, including anatomical characteristics, mechanism, diagnosis, fracture classification, treatment, prognosis, complications and progress.The most common mechanism of the injury is the so-called dashboard injury, in which the generally unrestrained driver or passenger hits his knee on the dashboard during a collision with the force of the impact being transmitted along the axis of the femur. The position of the hip such as adduction, flexion and rotation at the time of impact determines the hip dislocates with or without the head and/or acetabulum fracture. There are many classifications for this injury and Pipkin classification is the most acceptable. IDiagnosis should be done combined with anteroposterior pelvic X-ray view, lateral hip view, obturator oblique view and CT scan of hip joint, to prevent misdiagnosis. Recently, MRI examination was also used to evaluate the possible obturator externus muscle damage in hip fracture-dislocations. This muscle protects the medial femoral circumflex artery, which is sufficient for the blood supply to the femoral head. In addition, it also more clearly a reflection of the compression fracture of the femoral head surface.Despite different operative and non-operative treatment regimens, the outcome after femoral head fractures has changed little over the past decades. The initial trauma itself as well as secondary changes such as posttraumatic osteoarthritis, avascular necrosis or heterotopic ossification is often responsible for severe loss of function of the afflicted hip joint. Anatomic reduction of all fracture fragments seems to be a major influencing factor in determining the prognosis.There is still no clear evidence indicating whether to treat these fractures operatively or non-operatively, whether to fix or excise fragments and which surgical approach to use. Every dislocated hip should be reduced as soon as possible, multiple attempts at closed reduction are contraindicated. We choose closed reduction or open reduction and internal fixation according to the specific conditions, and different surgical approach, surgical methods according to fracture types. Removal of the intra-articular loose fragments and surgical stabilization of an unstable hip joint are imperative. The development of internal fixation materials is faster, from metal materials to the current Biodegradable materials. The most common complication is post-traumatic arthritis, followed by necrosis of the femoral head. Finally, the routine use of seat belts could have prevented many of these injuries.From December 2006 to February 2009 we treated 20 cases of femoral head fractures with posterior hip dislocations in our hospital, of which 17 cases of male, 3 cases of female. The age ranges from 16 years old to 58 years old, average 35.2 years old. According to Pipkin classification, 10 cases were type I, 3 cases were type II, 3 cases were type III, and 4 cases were type IV. According to different fracture types, 1 was treated with no operative method, 1 was treated with primary total arthroplasty, 1 was performed by fracture fragment excision1 and 17 of them were treated with open reduction and internal fixation. The follow - up period ranged from 3 months to 28 months, and the overall excellent and good rate was 45%.