[Experimental studies on the role of intramedullary alignment rods in the etiology of fat embolisms in knee endoprostheses]

Fatal fat embolism complicating cemented total knee replacement: another manifestation of the metabolic syndrome?

We report the case of a 52-year-old man who died of massive fat emboli 39 h after undergoing elective total knee replacement. His past medical history included hypertension, obesity and diabetes (most of the clusters of the metabolic syndrome). Post-mortem pathological examination showed fat embolism in the kidneys and the brain. This is the first reported case of fat emboli as the cause of death in an association with metabolic syndrome, and the case suggests that the fat embolism should be anticipated in over weight and obese individuals with three or more of the risk factors of the metabolic syndrome.

Orthopedic personnel roles in the OR for computer assisted total knee arthroplasty

The methods and problems associated with traditional total knee arthroplasty surgery and the development and advantages of computer-assisted surgery (CAS) are discussed in this article. In the next decade, CAS products have the potential to transform as many as 25% of all orthopedic surgical procedures from techniques that largely depend on line of sight and traditional instruments to techniques that use integrated surgical instruments and computer technology. This technology could revolutionize orthopedic surgery, the lives of patients, and the work of perioperative staff members during the next decade.

Fat embolism

Fat embolism syndrome is a collection of respiratory, haematological, neurological and cutaneous symptoms and signs associated with trauma and other disparate surgical and medical conditions. The incidence of the clinical syndrome is low (< 1% in retrospective reviews) whilst the embolisation of marrow fat appears to be an almost inevitable consequence of long bone fractures. There is debate over the pathogenesis of fat embolism syndrome and it seems a variety of factors interact to produce a spectrum of end organ damage. Many therapeutic interventions and prophylactic strategies have been tried with varying success. Current treatments are supportive and the condition is usually associated with a good outcome. The literature on fat embolism syndrome is extensive and this review aims to discuss the incidence, aetiology, pathophysiology, diagnosis and treatment of fat embolism.

In vivo femoral intramedullary pressure during uncemented hip arthroplasty

There is evidence in several animal and human studies that high intramedullary pressure in the femur is of causal significance for bone marrow release into the circulation, causing pulmonary fatty marrow embolization. A previous clinical study provided evidence that in uncemented hip arthroplasty, high intramedullary pressure and subsequent fat embolism with cardiorespiratory deterioration can occur. In this prospective clinical trial, the effect of five surgical techniques on the femoral intramedullary pressure was recorded intraoperatively in 36 patients during uncemented press fit hip arthroplasty. In Group A, the conventional surgical technique (slide hammer and femoral rasps) showed intramedullary hypertension during opening of the femoral canal, femur preparation, and prosthesis insertion. In Group B, a mechanical high frequency vibration rasp was used, instead of the slide hammer, and provided reduction of the intramedullary pressure peaks during opening of the femoral canal but could not prevent intramedullary hypertension during rasping and prosthesis insertion. In Group C, a modified surgical technique to prevent high intramedullary pressure reduced pressure peaks during opening of the femoral canal and resulted in a significant reduction of intramedullary pressure during femur preparation and prosthesis insertion compared with the conventional surgical technique used with Group A. In Group D the results of the modified surgical technique could be improved additionally by using the high frequency vibration rasp, instead of the slide hammer. In Group E conventional surgical technique in combination with a distal venting hole has not proven to be efficient in uncemented hip arthroplasty. Based on the results of this in vivo study, the proposed modified surgical technique in cementless hip arthroplasty can be recommended to avoid high intramedullary pressure peaks, which should minimize the risk of significant bone marrow release into the circulation and the risk for cardiorespiratory deterioration caused by fat embolism.