title: Outcome after tantalum rod implantation for treatment of  femoral head osteonecrosis: 26 hips followed for an average of 3 years.
abstract: OBJECTIVE
  Tantalum rod implantation has recently been proposed for treatment of early stages of femoral head osteonecrosis.The purpose of our study was to report the early results of its use in pre- and post-collapse stages of the disease.
  
  
  METHODS
  We studied prospectively 27 patients who underwent tantalum rod implantation for treatment of nontraumatic femoral head osteonecrosis between December 2000 and September 2005. Patients were evaluated radiologically and clinically using the Steinberg classification and the Harris hip score (HHS). Disease stage varied between stages II and IV. Mean follow-up time was 38 (15-71) months.
  
  
  RESULTS
  1 patient (1 hip) died 15 months after surgery for reasons unrelated to it. 13 of 26 hips remained at the same radiographic stage, and 13 deteriorated. Mean HHS improved from 49 to 85. 6 patients required conversion to total hip arthroplasty. When the procedure was used for stages III and IV, both radiological outcome and revision rates were worse than for the stage II hips. There was, however, no difference in postoperative HHS between patients at pre- and post-collapse stages at the time of initial evaluation. Survivorship, with revision to THA as the endpoint,was 70% at 6 years.
  
  
  CONCLUSIONS
  The disease process does not appear to be interrupted,but there was a significant improvement in hip function initially in most hips. Tantalum rod implantation is a safe "buy-time" technique, especially when other joint salvage procedures are not an option. Appropriate patient selection and careful rod insertion are needed for favorable results.
authors.affiliation: Department of Orthopedic Surgery, School of Medicine, University of Thessalia, Larissa, Greece.
authors.forename: Sokratis E
authors.initials: SE
authors.lastname: Varitimidis
authors.forename: Apostolos P
authors.initials: AP
authors.lastname: Dimitroulias
authors.forename: Theophilos S
authors.initials: TS
authors.lastname: Karachalios
authors.forename: Zoe H
authors.initials: ZH
authors.lastname: Dailiana
authors.forename: Konstantinos N
authors.initials: KN
authors.lastname: Malizos
mesh_terms: D000293:Adolescent; D000368:Aged; D005260:Female; D005271:Femur Head Necrosis / Q000000981:diagnostic imaging / Q000601:surgery*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011446:Prospective Studies; D019919:Prosthesis Implantation; D011859:Radiography; D012086:Reoperation; D013635:Tantalum; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D013635:Tantalum