Cerebral embolization presenting as delayed, severe obtundation in the postanesthesia care unit after total hip arthroplasty.

Catastrophic neurologic events occur rarely postoperatively and must be diagnosed quickly. A 63-year-old woman who had undergone uneventful total hip arthroplasty experienced obtundation after admission to the postanesthesia care unit. Cranial magnetic resonance imaging revealed multiple lesions consistent with ischemia or infarction, and fat cerebral embolism was diagnosed. We describe the numerous complications that may occur in patients in the postanesthesia care unit and review the differential diagnosis of altered mental status in such patients. Paradoxical cerebral fat embolization must be considered in the differential diagnosis of altered mental status after pelvic or long bone fracture or lower extremity major joint replacement, and this condition may occur despite normal pulmonary function and no patent foramen ovale or right-to-left intracardiac shunt. Magnetic resonance imaging with T2-weighted sequences is the cranial imaging study of choice for early evaluation of patients with sudden multifocal neurologic deficits and suspected fat embolism syndrome.

Surgical management of delayed union and nonunion of the tibia.

A review of 163 patients seen between 1963 and 1975 with tibial nonunion revealed that operative treatment of the fracture, soft tissue injury, infection, and comminution appeared to have a role in the nonunion. The patients usually were seen between five and 12 months after injury. Multiple methods, involving both soft tissue and bone, were used to treat the nonunion. Phemister grafting was both the most frequent (21%) and the most successful (83%) procedure. Plate with graft and external compression with graft were both used with success (73% and 83%, respectively) in smaller patient populations. Infection tended to decrease the rate of successful union. The need to individualize treatment is important.

Arthrodesis of the knee following failed total knee arthroplasty.

In forty-five patients, who had an arthrodesis because of failed total knee arthroplasty, the cause was infection in forty, instability in two, failure of the prosthesis in two, and loosening in one. The arthrodesis succeeded in twenty-nine (81%) of thirty-six patients who had had a minimally or partially constrained arthroplasty and in five (56%) of nine who had had a hinge-type prosthesis inserted. The reasons for failure were severe bone loss, persistent sepsis, and loss of bone apposition after manipulation. The technique of arthrodesis did not seem to influence the final result. External fixation most commonly had to be used because of the infections and the device was kept in place for an average of ten weeks, after which immobilization in a cast was used until the arthrodesis healed.