The state of the articular cartilage at the time of surgery as an indication for rotational acetabular osteotomy

Abstract

We have studied whether the state of the articular cartilage at the time of rotational acetabular osteotomy for dysplasia of the hip affects the outcome 2 to 5.5 years after surgery. Arthroscopy in 57 patients (59 joints) at the time of the operation showed grade-0 changes in seven, grade-1 in nine, grade-2 in 17, grade-3 in 14 and grade-4 in 12 joints, according to the classification of Outerbridge. There was radiological evidence of the progression of arthritis in four joints which were classified at arthroscopy as grade 4.Stepwise regression analysis showed that damage to acetabular or femoral articular cartilage significantly affected the progression of arthritis. We conclude that the short-term results of successful rotational acetabular osteotomy for dysplasia are affected by the state of the articular cartilage. Periacetabular osteotomies for osteoarthritis (OA) secondary to hip dysplasia have theoretical advantages over other pelvic procedures such as the Chiari osteotomy, 1 because they alter the position of the acetabulum en bloc allowing cover of the femoral head by cartilage. 2-6 These procedures have produced satisfactory long-and medium-term results for early OA secondary to dysplasia of the hip. 6,7 When progression of the degenerative changes has been seen, the presence of preoperative OA has been cited as the cause. Arthroscopic observations of the articular cartilage in early OA of the hip, however, vary widely. 8 Our aim was to determine how the state of the articular cartilage affects the outcome of rotational acetabular osteotomy carried out for dysplasia of the hip. Patients and MethodsOf 62 patients (65 joints) who underwent rotational acetabular osteotomy (RAO) 5 between 1994 and 1998, we studied 57 (59 joints) who also had an arthroscopy during the operation. There were 55 women (57 joints) and two men (2 joints) with a mean age at the time of surgery of 37.5 years (12 to 57). OA of the hip was classified into four stages according to the radiological appearance: 1) prearthritis, no osteoarthritic change; 2) early, with slight narrowing of the joint space associated with sclerosis of the subchondral bone; 3) advanced, with narrowing of the joint space, cystic lucencies and small osteophytes; and 4) end stage, with disappearance of the joint space and marked formation of osteophytes. Ten joints had prearthritis and 35 were in the early stage and 14 in the advanced stage. The mean followup was for 3 years and 2 months (2 to 6.5 years). The indications for RAO were acetabular dysplasia, characterised radiologically by a centre-edge (CE) angle of less than 20° and pain severe enough to interfere with normal activities. 9 Patients with improvement in cover of the femoral head and joint congruency on an anteroposterior (AP) plain radiograph in abduction, were considered to be suitable for surgery. RAO was carried out using the technique of Ninomiya and Tagawa 5 with one modification in that the rotated acetabulum was fixed by two poly-L-lactic acid screws (Gunze, Kyoto, Japan) instead of Kirsc...

Effect of intra-articular lesions on the outcome of periacetabular osteotomy in patients with symptomatic hip dysplasia

“…[11][12][13]15,19,22,35 A recent study by the Bern group reported a survival rate of 87.6% at ten years, and 60.5% at 20 years after Bernese periacetabular osteotomy. 17 We demonstrated that TOA provides significant correction of deformity and symptomatic relief for patients with DDH.…”

“…4,21 This variation in cartilage degeneration is suggested to affect the results of the osteotomy. 22 However, the mechanism by which the intra-articular lesions influences the outcome remains unclear.…”

Joint Congruency as an Indication for Rotational Acetabular Osteotomy

“…Some authors described the relationship between postoperative data and final results of osteotomy [5,15,17,19,31] (Table 3); however, postoperative data, unlike preoperative data, are not useful in planning the surgery. Several authors have suggested periacetabular repeat osteotomy could be considered in patients who showed improvement in joint congruency with the hip in abduction [1,11,26,30]. Postoperative joint congruency is reportedly a useful predictor of postoperative outcomes [31].…”

“…The inclusion criterion for this study was Stage 3 (advanced stage) osteoarthritis. To evaluate joint congruency, we used the modified classification according to Yasunaga et al [30]. Preoperative joint congruency in abduction and postoperative congruency in neutral position were classified into three grades.…”

“…In a study of the long-term results of RAO for advanced osteoarthritis of the hip [16], we identified contraindications to RAO in patients who have a deformity of the femoral head that is associated with advanced osteoarthritis; however, at followup we could not predict the patients with excellent results using preoperative roundness of the femoral head. Based on putative predictive factors, numerous studies report the use of preoperative functional radiographs to identify candidates for periacetabular osteotomy [1,11,26,30] but these studies did not consider congruency in abduction.…”