title: Clinical and radiographical results of 179 thrust plate hip prostheses: 5-14 years follow-up study.
abstract: BACKGROUND
  The thrust plate hip prosthesis (TPP) is a bone-reserving prosthesis for cementless fixation at the metaphysis of the proximal femur. We retrospectively evaluated the results of 162 patients (179 hips) who underwent hip arthroplasty using TPP.
  
  
  METHODS
  Eighty-three patients (87 hips) suffered from osteoarthritis of the hip joint (OA group), 79 patients (92 hips) from osteonecrosis of the femoral head (ON group). The mean age at surgery was 55 years in the OA group and 47.4 years in the ON group. The mean follow-up period was 97 months in the OA group and 104 months in the ON group. For these patients, we evaluated the results clinically and radiographically.
  
  
  RESULTS
  The mean Merle d'Aubigne's score improved from 8.2 to 16.9 in the OA group and from 9.1 to 16.6 in the ON group at the final follow-up. Early mechanical loosening of TPP was observed in two hips of OA and one hip of ON. In one patient of ON, bilateral TPPs had to be removed 5 years postoperatively because of infection. Two female patients with ON suffered from a spontaneous femoral fracture below the tip of the lateral plate. Kaplan-Meier survivorship using TPP removed for any reason as the end point was 97.7% in the OA group and 90.3% in the ON group after 13 years.
  
  
  CONCLUSIONS
  The middle-term results of the TPP were satisfactory if the indication for the TPP and the operative procedure were appropriate. The TPP is a useful and safe prosthesis for relatively young patients with not only osteoarthritis of the hip but also osteonecrosis of the femoral head.
authors: Department of Artificial Joints and Biomaterials, Hiroshima University, Graduate School of Biomedical Sciences, Minami-ku, Hiroshima, Japan. yasuyuji@hiroshima-u.ac.jp
authors: Yuji
authors: Y
authors: Yasunaga
authors: Takuma
authors: T
authors: Yamasaki
authors: Toshihiko
authors: T
authors: Matsuo
authors: Tomokazu
authors: T
authors: Yoshida
authors: Seigo
authors: S
authors: Oshima
authors: Junji
authors: J
authors: Hori
authors: Keiichiro
authors: K
authors: Yamasaki
authors: Mitsuo
authors: M
authors: Ochi
mesh_terms: D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation*; D005260:Female; D005264:Femoral Fractures / Q000209:etiology; D005500:Follow-Up Studies; D006621:Hip Joint / Q000000981:diagnostic imaging; D006622:Hip Prosthesis; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000000981:diagnostic imaging / Q000601:surgery*; D010147:Pain Measurement; D011183:Postoperative Complications; D011475:Prosthesis Failure; D011859:Radiography; D020127:Recovery of Function; D012189:Retrospective Studies; D013530:Surgical Wound Infection; D016896:Treatment Outcome