Friday, February 25, 2005
Early failure identified with FSR for post-collapse AVNThe optimal treatment for young, active patients with post-collapse femoral head avascular necrosis continues to be controversial. Femoral surface replacement (FSR) has been promoted as a treatment with hopes that it will delay the need for total hip arthroplasty (THA) in these patients.
Surgeons should exercise caution when considering FSR for young young patients with femoral head AVN, according to researchers for Poster P045. In their study, nearly two-thirds of patients treated with FSR required conversion to THA or had moderate to severe hip pain at early follow-up.
Researchers identified 32 consecutive patients (37 hips) who underwent FSR for post-collapse femoral head AVN. The average follow-up was 33 months (range: 6-88 months). The average age of the patients was 36 years (range: 18-51 years). All resurfacing procedures were performed for post-collapse AVN. Failure was defined as either conversion to THA or moderate or more severe hip pain. Kaplan-Meier survivorship analyses were performed to predict survival of the FSR components.
At average 33 month follow-up, 15 of the 37 hips with FSR (40.5 percent) had been converted to THA because of pain. Average time from FSR to THA was 23.5 months. In addition, 9 of 37 hips with FSR (24.3 percent) were classified as failures because of moderate or severe groin pain. This brought the total failure rate to a surprisingly high 64.3 percent. No statistically significant correlation could be found between implant failure and the demographic or radiographic variables examined in this study.
Kaplan-Meier survivorship analysis predicted that 75 percent of the hips with FSR would be either revised or unacceptably painful at the 5-year followup.
Researchers noted that femoral head resurfacing for AVN is an unpredictable procedure. Additionally, FSR can have a high incidence of early pain and conversion to THA. Results were so compelling that this procedure is no longer offered as a treatment option for post-collapse AVN at the authors' institution.
Researchers included Matthew W. Squire, MD, of Iowa City, Iowa, and Thomas K. Fehring, MD; William G. Griffin, MD; Susam M. Odum, MA, and J. Bonhannon Mason, MD, all of Charlotte, N.C.