Unique Complication After Hip Resurfacing

Femoral neck fracture is a unique complication after total hip joint resurfacing. In this study, surgeons explore the incidence (how often this happens) and the risk factors for this type of fracture.

Five hundred and fifty (550) patients received a metal-on-metal total hip resurfacing from one surgeon. Femoral neck fractures were much more common in the first group of patients to have this procedure. At first, the incidence of femoral neck fracture was 2.5 per cent. This rate went down to 0.4 per cent by the end of the study.

Surgical technique and learning how to do the procedure probably accounted for the early complications seen in this study. After analyzing the data, the authors also noted that women and obese patients had the highest incidence of fractures.

Women, especially postmenopausal women, are more likely to have decreased bone density. Poor bone stock at the femoral neck can lead to fractures. Surgeons who do enough of these operations develop the skill and technique needed to avoid errors leading to fractures.

The authors note that joint hip resurfacing should not be done on a casual basis. The surgeon must be trained for this method and use it routinely.

Selecting the right patient is also important. Body mass index (BMI) should be less than 35. Normal BMI is a range between 20 and 25. Overweight is between 25 and 30. Obese is defined as a BMI between 30 and 40.

Joint resurfacing is a more difficult operation to perform than a total joint replacement. With joint resurfacing, more of the bone is saved. The femoral head is not cut off like in the total joint replacement. This makes it more difficult for the surgeon to see the acetabulum (socket) during the operation.

With the right training, education, and patient selection, hip joint resurfacing is a very successful procedure. More than 90 per cent of patients who receive resurfacing have an excellent outcome up to five years later. More long-term studies are being done to find out the long-term results.



References: David R. Marker, BS, et al. Femoral Neck Fractures After Metal-on-Metal Total Hip Resurfacing. A Prospective Cohort Study. In The Journal of Arthroplasty. October 2007. Vol. 22. No. 7. Supplement 3. Pp. 66-71.