Abstract
BACKGROUND
There is no report of additional type of bulk bone grafting (Ad-BG) method with impaction morselized bone graft for reconstruction of shallow dysplastic hip in total hip arthroplasty. The purpose of this study was to define the shallow acetabulum and to evaluate the clinical and radiographic results of primary total hip arthroplasty (THA) with Ad-BG method.
MATERIALS and METHODS
With modification of Crowe's classification, shallow dysplasia was defined and classified (Fig. 1). Between October 1999 and August 2008, 120 hips of 302 THAs for dysplastic hip were defined as shallow and Ad-BG was done in 96 hips (80% of shallow hips). For 24 hips with shallow dysplasia, THA were performed by using conventional type of interpositional bulk bone graft (Ip-BG) (8 hips) or without bone graft by using rigid lateral osteophyte. All patients were followed clinically using the Japanese Orthopaedic Association (JOA) score and also Merle d'Aubigne and Postel (M&P) scores in a prospective fashion, and radiographs were analyzed retrospectively. The criteria used for determining loosening were migration or total radiolucent zone between the prosthesis (or bone cement) and host bone. The mean follow-up periods were 8.0 ± 2.3 (5.0–13.5) years.
Operative technique
Resected femoral head was sliced with thickness of 1–2 cm, and then a suitable size of the bulk bone block was placed on the lateral cortex of the ilium and fixed by polylactate absorbable screws. Autogenous impaction morselized bone grafting with or without hydroxyapatite granules was performed in conjunction with a cemented socket (Fig. 2). The same surgeon assisted by his colleagues operated all of the cases.
RESULTS
No acetabular components were revised except for a case with shallow and Crowe type IV acetabulum. The mean JOA and M&P score for the hips improved from preoperative 39 and 6 points to postoperative 93 and 17 points respectively. Radiographically, the Ad-BGs in most of the cases were remodeled and recognized reorientation within 2 years postoperatively.
CONCLUSIONS
The authors report good results of acetabular reconstruction with the use of Ad-BG technique in conjunction with impaction morselized bone graft for shallow dysplastic hip in primary THA. Osteointegration and good clinical outcome were achieved in most of cases. However longer term outcome should be the subject of further investigation.