How best to fix a broken hip. Fractured Neck of Femur Health Outcomes Project Team.

OBJECTIVES: To develop evidence-based guidelines for the treatment of proximal femoral fractures to optimise functional outcome while minimising length of stay in hospital. DATA SOURCES: Systematic literature search of MEDLINE and CINAHL computer databases, bibliographies, and current contents of key journals for 1966-1995. STUDY SELECTION: English-language randomised controlled trials of all aspects of acute-care hospital treatment of proximal femoral fracture among subjects aged 50 years and over with proximal femoral fractures not due to metastatic disease. DATA EXTRACTION: Two independent reviewers, blinded to authors, institution and study results, followed a standard Cochrane Collaboration protocol and assessed study quality and treatment conclusions. When necessary, a third review was performed to reach consensus. RESULTS: Of the 120 articles published between 1966 and December 1995, 97 met the inclusion criteria. Fifteen clinical interventions were reviewed. Five were supported by National Health and Medical Research Council (NHMRC) level I evidence (prophylactic anticoagulants, prophylactic antibiotics, regional anaesthesia, pressure-relieving mattresses, and internal surgical fixation), two had no supporting randomised controlled trial evidence (time to surgery, time to mobilisation after surgery) and the remainder were classified as having Level II evidence. A review of current practice (1993-94) identified wide variability in these interventions across five acute-care hospitals in the Northern Sydney Area Health Service. CONCLUSIONS: Randomised controlled trial evidence (NHMRC Levels I and II) exists for many, but not all, aspects of hip fracture treatment. There is a need for changes to be made to some aspects of practice in accordance with evidence-based guidelines.

Ultrastructural studies of adherence of Staphylococcus aureus in experimental acute hematogenous osteomyelitis.

A model of acute hematogenous osteomyelitis initiated by injection of Staphylococcus aureus into 29-day-old chickens was used. Transmission electron microscopy showed that the bacteria adhered to exposed cartilage matrix in the metaphyseal region of long bones but not to adjacent vascular linings or to erythrocytes. It is proposed that the combination of exposure of growth plate cartilage during normal bone growth and the ability of S. aureus to adhere to this cartilage is the mechanism for initiation of infection which proceeds to an osteomyelitic abscess.

The use of ceramics for bone replacement. A comparative study of three different porous ceramics.

Ceramics have many properties which might make them suitable alternatives to bone grafts. This present study was done to find a suitable biodegradable porous ceramic for human bone replacement. Three different porous ceramics (calcium aluminate, calcium hydroxyapatite and tricalcium phosphate), with interlinked pores of two size ranges (150 to 210 micron), were implanted into the skulls of rats and rabbits for up to six months; the interaction with surrounding bone, which is virtually devoid of bone marrow, was then assessed. The ceramics caused no adverse biological response. Tissue ingrowth into pores throughout the implant was seen in all three types and in both pore sizes of ceramic, but the density of the penetrating tissue was far less for calcium aluminate than for calcium hydroxyapatite or tricalcium phosphate. For each type of ceramic, the soft-tissue ingrowth was more dense with the larger pore size, and with a longer period of implantation. Bone ingrowth was not usually seen within the pores of any ceramic. There were no differences in the histological findings between the rats and the rabbits. The results demonstrate that it is possible to produce ceramic materials with a porous structure which allows ingrowth of tissue and biological fluids.

Acute haematogenous osteomyelitis: II. The effect of a metaphyseal abscess on the surrounding blood supply.

Three major vessel types--metaphyseal, epiphyseal and transphyseal vessels--were identified in the region of the growth plate following perfusion of the vasculature of the chicken leg with a solution of Berlin Blue. Following the production of osteomyelitis, obstruction to the blood supply adjacent to the abscess was rapid and was clearly demonstrated due to a lack of perfusion of the involved vessels with Berlin Blue. The extent of disturbance to the blood supply was dependent on the type of vessel involved in the inflammatory process. The efficacy of bloodstream therapy is discussed in relation to these findings.

Acute haematogenous osteomyelitis: an experimental model.

A simple and reproducible model of acute haematogenous staphylococcal osteomyelitis is described. Twenty-nine day-old chickens were inoculated intravenously with 10(4)-10(8) viable organisms Staphylococcus aureus per kg body weight and were killed 1-8 days after inoculation. Macroscopic septic foci could be detected within 24 hr of inoculation and were most commonly situated in the metaphyseal region of the proximal tibia and distal femur. Lesions in other organs were not observed. The production of osteomyelitis was dependent on the bacterial inoculum size. It was estimated that 5.5 X 10(5) viable organisms per kg body weight of chicken were required to produce osteomyelitis in 50 per cent of injected chickens. Chicken weights were monitored throughout the experiment. A close negative correlation existed between the logarithm of the bacterial inoculum size and the chicken growth rate in the first 24 hr following inoculation (r = -0.968, P less than 0.01). The chicken growth rate was therefore used as an accurate predictor of osteomyelitis in individual chickens.