Do modern techniques improve core decompression outcomes for hip osteonecrosis?

Abstract

Core decompression procedures have been used in osteonecrosis of the femoral head to attempt to delay the joint destruction that may necessitate hip arthroplasty. The efficacy of core decompressions has been variable with many variations of technique described. To determine whether the efficacy of this procedure has improved during the last 15 years using modern techniques, we compared recently reported radiographic and clinical success rates to results of surgeries performed before 1992. Additionally, we evaluated the outcomes of our cohort of 52 patients (79 hips) who were treated with multiple small-diameter drillings. There was a decrease in the proportion of patients undergoing additional surgeries and an increase in radiographic success when comparing pre-1992 results to patients treated in the last 15 years. However, there were fewer Stage III hips in the more recent reports, suggesting that patient selection was an important reason for this improvement. The results of the small-diameter drilling cohort were similar to other recent reports. Patients who had small lesions and were Ficat Stage I had the best results with 79% showing no radiographic progression. Our study confirms core decompression is a safe and effective procedure for treating early stage femoral head osteonecrosis.

Fig. 1

The Ficat and Arlet system [18] has historically been the most frequently used staging modality. However, as noted in this graph, a large percentage of recent core decompression studies have reported using various other radiographic staging systems such as the Pennsylvania [81], ARCO [55], and Ohzono classifications [60].

Fig. 2

This figure provides the percentage of studies that used various clinical assessment modalities. The Harris hip score [22] and the Merle d’Aubigné-Postel scale [49] were the two most common evaluation methods used to assess clinical outcomes.

Fig. 3

The studies reviewed in our meta-analysis were grouped according to their levels of evidence [14], and the proportion of studies for each level is presented in this chart. There have been relatively few randomized, prospective studies concerning osteonecrosis of the hip, and the majority of the reports have been level of evidence IV.

Fig. 4

The most frequently reported etiology/risk factors are listed and the number of studies in our meta-analysis that reported the outcomes of patients who were diagnosed with each of these factors is noted.