Bacterial Culture Study of the Hip Joint Fluid during Primary Total Hip Arthroplasty / 대한정형외과학회잡지

Infection in primary total hip arthroplasty may cause catastrophic results and is the major reason for implant failure. The purpose of this study was to evaluate the utility of the hip joint fluid culture as a method of predicting the possibility of a hip joint infection by calculating the sensitivity, specificity and accuracy. We performed 628 primary total hip arthroplasty and aerobic and anaerobic bacterial cultures for hip joint fluid between January 1989 and June 1996. The hip joint fluid culture was routinely performed to evaluate the utility of the femoral head for bone banking. Thirty-two cases out of the 628 hips showed positive intraoperative culture and 596 cases showed negative intraoperative culture. The isolated organisms from 32 positive cultures were 11 for Staphylococcus aureus, eight for Staphylococcus coagulase negative, seven for Enterococcus, three for E.coli and one each for Enterobacter, Acinetobacter and Pseudomonas. Anaerobic culture was negative in all cases. In the positive intraoperative culture cases, none had delayed infection during the follow-up period. But in the negative intraoperative culture cases, one case had acute infection and two cases had delayed infection. In the case with acute infection, Staphylococcus aureus was isolated and on two cases with delayed infection, Enterococcus and Staphylococcus coagulase negative were isolated, respectively. All 32 positive culture cases were fa~lse positive and 595 negative culture cases were true negative and one negative culture case was fa~lse negative. The sensitivity of the hip joint culture was 0%, the specificity was 94.9% and the accuracy was 0%. The specificity of hip joint fluid culture in primary total hip arthroplasty was high, hut the sensitivity score was zero. Therefore, the hip joint fluid culture should not be used for a routine check of infection status in primary total hip arthroplasty. We recommend the hip joint fluid culture in revision arthroplasty or hips in which infection is clinically suspected.

The Relationship between the Fracutures of the Hip and the Bone Mineral Density over Fifty years / 대한정형외과학회잡지

Osteoporosis has been described as the most common disease in the old age group. As the bone mineral density decreases, the skeleton becomes more prone to fracture. Hip fractures occur late in life following substantial reduction in skeletal mass. So the incidence of hip fracture is increasing due to prolongation of average life span. The bone density of femoral neck, Ward triangle, and trochanteric region were measured by dual energy x-ray absorptiometry (DEXA) in 15 patients with femoral neck fractures and in 58 patients with intertrochanteric fractures to evaluate the relationship between bone mineral density (BMD) value and fracture type. The results were as follows 1. In femoral neck fracture group, the mean BMD value was 0.59+/-0.02 g/cm2 in femoral neck, 0.38+/-0.08 g/cm2 in Ward triangle and 0.48+/-0.09 g/cm2 in trochanteric region. In intertrochanteric fracture group, the mean BMD value was 0.57+/-0.09 g/cm2 in femoral neck, 0.39+/-0.10 g/cm2 in Ward triangle, and 0.47+/-0.13 g/cm2 in trochanteric region. 2. In femoral neck fracture group, the fracture threshold value was 0.75 g/cm 2 in femoral neck, 0.60 g/cm2 in Ward triangle and 0.67 g/cm2 in trochanteric region. In intertrochanteric fracture group, the fracture threshold value was 0.63 g/cm2 in femoral neck, 0.51 g/cm2 in Ward triangle, and 0.57 g/cm2 in trochanteric region. In conclusion, there was no statistical relationship in BMD value between neck fracture and intertrochanter fracture group, and no statistical relationship between BMD value and each fracture type in femoral neck and intertrochanter fracture. The type of hip fracture may be related to the degree of trauma rather than the value of the BMD.