Treatment of femoral head osteonecrosis in the United States: 16-year analysis of the Nationwide Inpatient Sample

Abstract

Background: Many surgical interventions are used to treat osteonecrosis of the femoral head. The instance and distribution of these various procedures may give some insight into the practicing community's understanding of the efficacy of these treatments. We therefore sought to determine trends in the types and numbers of procedures performed for atraumatic osteonecrosis from 1992 through 2008 in the United States.

Questions/purposes: (1) How has the overall incidence of surgical treatment for atraumatic osteonecrosis changed over this time period; and (2) how has the percentage of THA performed for osteonecrosis (compared with joint-preserving procedures) changed over this time period?

Methods: The Nationwide Inpatient Sample database was used to collect information for all patients who had an International Classification of Diseases, 9(th) Revision diagnosis of hip osteonecrosis between 1992 and 2008. Procedures were collated according to frequency, and trends were analyzed for joint-preserving and joint-replacing procedures.

Results: The total number of procedures performed over this time period for osteonecrosis of the hip increased from 3570 procedures to 6400 procedures per year. In 1992, 75% (n = 2678) of the procedures performed to treat osteonecrosis of the hip were THA, which increased to 88% (n = 5632) in 2008. The percentage of joint-preserving procedures consequently decreased from 25% to 12% over this period.

Conclusions: Previously, THA was believed to have poor survivorship and clinical results for the treatment of osteonecrosis of the hip, but reports since 1993 have suggested improved survivorship of these reconstructions. Our study suggests that surgeons have incorporated this into their practice patterns, in that an increasing percentage of patients with this diagnosis are treated with THA. Additionally, the total number of procedures performed for osteonecrosis has increased, which may reflect an improved awareness of this disease and more aggressive approaches to diagnosis and treatment.

Fig. 1

This figure represents the total number of surgical procedures performed for osteonecrosis of the femoral head.

Fig. 2

This figure represents the total number of procedures performed for osteonecrosis of the femoral head stratified by THA or joint-preserving procedures.

Fig. 3

Relative amounts of joint-preserving procedures are compared with THA. The primary Y axis (“Percent”; left axis) refers to each type of procedure; the secondary Y axis (“Total Procedures”; right axis) refers to the nominal number of total procedures performed during that year.

Fig. 4

Relative amounts of joint-preserving procedures performed for osteonecrosis of the femoral head are here stratified by procedure. The primary Y axis (“Percent”; left axis) refers to each type of procedure (core decompression, osteotomy, vascularized fibular graft, nonvascularized graft, partial THA); the secondary Y axis (“Total Procedures”; right axis) refers to the nominal number of total procedures (joint- and nonjoint-preserving) performed during that year.