Rotational acetabular osteotomy (RAO) has been reported to be effective in improving symptoms and preventing osteoarthritis (OA) progression in patients with mild to severe develomental dysplasia of the hip (DDH). However, some patients develop secondary OA even when the preoperative joint space is normal; determining who will progress to OA is difficult. We evaluated whether the preoperative cartilage condition may predict OA progression following surgery using T2 mapping MRI. We reviewed 61 hips with early-stage OA in 61 patients who underwent RAO for DDH. They underwent preoperative and five-year postoperative radiological analysis of the hip. Those with a joint space narrowing of more than 1 mm were considered to have 'OA progression'. Preoperative assessment of articular cartilage was also performed using 3T MRI with the T2 mapping technique. The region of interest was defined as the weightbearing portion of the acetabulum and femoral head.Aims
Methods
A special surgical technique and consideration is necessary in the total hip arthroplasty for dysplastic osteoarthritis after Kalamchi and MacEwen Type III or IV deformity (so called “Perthes-like-deformity”). There have been few reports concerning the total hip arthroplasty for “Perthes-like-deformity”. We evaluated the clinical and radiological outcome of 52 uncemented hip arthroplasties for the lesion. We have performed 106 hips of uncemented total hip arthroplasty for dysplastic osteoarthritis after Kalamchi and MacEwen Type III or IV deformity. Among them, 52 hips of 47 patients (11 males and 41 females) were evaluated with minimum of three years follow-up. The average age at the surgery was 52 (28 to 65). The average follow-up period was 4.8 (3 to 8.1) years. Against the developmental dysplasia or dislocation, 29 hips of 26 patients had been treated by casting or surgery in infancy. Thirteen hips of 11 patients had no previous treatment before the arthroplasty. Spongiosa metal cup (GHE: ESKA implants, Lübeck, Germany) was used for 33 hips of 28 patients and Zweymüller type cup (Allo-classic cup: Zimmer Inc., Warsaw, IN, Bicon cup: Smith &
Nephew Orthopedics AG, Rotkreuz, Switzerland) for 19 hips of 19 patients. Spongiosa Metal stem (GHE: ESKA implants) was used for 23 hips of 19 patients and Zweymüller type stem (Alloclassic stem: Zimmer Inc., SL stem: Smith &
Nephew Orthopedics AG) for 29 hips of 28 patients. The average operative time was 108 (53 to 233) minutes. The average blood loss during the surgery was 731(150 to 1749) milliliters. The adductor tendon release was added in 28 hips of 26 patients against the severe contracture. The patients were evaluated clinically (pre-surgical history, hip score, leg length discrepancy, Trendelenburg sign, and gait function) and radiologically (ATD before the surgery, alignment, and stability of implants). Average ATD before the surgery was −2.2 (−28 to 17) millimeters. The average leg length discrepancy was 1.9 (0 to 7) centimeters before the surgery and was improved to 0.1 (0 to 1) centimeters after the surgery. The average hip score was 54 (23 to 80) before the surgery and was improved to 90 (69 to 100) after the surgery. At the final follow-up, Trendelenburg sign was positive in 14 hips of 14 patients (26.9%) and the limping was not obvious in 38 hips of 33 patients (73.1%). All implants were stable at the final follow-up. “Perthes-like-deformity” often has the severe deformity. It has a shortening or an absence of the neck and an excessive antetorsion of the femur. When it has the coxa magna, the acetabulum is shallow, has the narrow anteroposterior diameter, and has the thin wall like the osteophyte. It is frequently accompanied by shortening of leg and contracture, as the lesion arises from the development disorders. Thus, the total hip arthroplasty, especially uncemented one, is complicated. However, the satisfactory result can be obtained by careful consideration and surgical procedure such as a provision against the bleeding and the soft tissue release.
