title: [The results of cementless Zweymüller hip system: 5 to 11 years follow-up study].
abstract: OBJECTIVE
  To analyze the intermediate-term results associated with the use of Zweymtiller hip system.
  
  
  METHODS
  Review the 116 cases (142 hips) who were treated with total hip replacement from 1996 to 2002 by a single surgeon using cementless Zweymüller hip systems.
  
  
  RESULTS
  Sixty-one cases (77 hips) were followed up, 50 cases (64 hips) were evaluated both clinically and radiographically while 5 cases (6 hips) and 6 cases (7 hips) were only evaluated clinically and radiographically respectively. The average follow-up period was 7.3 years (range 5 to 11 years). The mean preoperative Harris Hip Score was 46 while the mean postoperative Harris Hip Score was 93. Distal cortical hypertrophy and medullary sclerosis were observed in 30 hips (42.3%) and 33 hips (46.5%) respectively. Heterotopic ossification arose in 45 hips (63.4%). Radiolucent lines occurred in 27 stems (38.0%) but in no cups. Radiolucent lines were mostly observed in Gruen zones 1. Osteolysis occurred in 7 cups (9.9%) and 18 stems (25.4%). Osteolysis was mostly observed in Delee Zone 3 and Gruen zone 7. In the distal Gruen zones 3, 4 and 5, no radiolucent line or osteolysis was observed. No hips had been revised, 3 cups needed revision surgery because of aseptic loosening.
  
  
  CONCLUSIONS
  The 5-11 years follow-up results are satisfactory, but osteolysis is common.
authors: Department of Spine and Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors: Yu-li
authors: YL
authors: Guo
authors: Zhan-jun
authors: ZJ
authors: Shi
authors: Da-di
authors: DD
authors: Jin
authors: Zong-sen
authors: ZS
authors: Jing
authors: Jian
authors: J
authors: Wang
authors: Zhi-gang
authors: ZG
authors: Zhu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip; D005260:Female; D005500:Follow-Up Studies; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome; D055815:Young Adult