Metal type of the femoral stem in total hip arthroplasty.

OBJECTIVE: To compare the influence of two different cemented stems each made of different alloys on survival and outcome. MATERIAL AND METHODS: We analyzed 341 total hip replacements performed in 1998-2001. Two types of prostheses were implanted. Biomet Bi-Metric titanium stem, cobalt-chrome head and ultra high molecular weight all poly cup were implanted in 102 cases. Aesculap Centrament cobalt-chrome stem, head and ultra high molecular weight all poly cup were implanted in 239 cases. All prostheses were cemented; Palacos bone cement with gentamycin was used in all cases. Cementing technique was consistent in all cases. All data were collected prospectively. For every total hip replacement the form was filled in. The documental patients' data, implant type, cement type, cementing technique, intraoperative and postoperative complications were registered. All revision surgeries were registered; the patients' death dates were recorded from national register database up to December 31, 2004. Kaplan-Meier curves were used to calculate implant survival rates. RESULTS: The total implant survival for Biomet Bi-metric prostheses was 98%, 7 years postoperatively. The total implant survival as Aesculap Centrament prostheses were used was 98%, 6 years postoperatively. CONCLUSION: The mid-term implant survival of Biomet Bi-Metric titanium stems was the same as survival of Aesculap Centrament cobalt-chromium stems.

Total hip replacement for the treatment of femoral neck fractures. Long-term results.

OBJECTIVE: To evaluate the outcome of total hip replacement after femoral neck fractures and analyze implant survival rates, complication rates, and mortality after surgery. MATERIAL AND METHODS: We analyzed 135 primary hip replacements and 8 revision hip replacements performed in 1991-2003 years. Femoral neck fracture was the diagnosis for all primary hip replacements. All patients we analyzed prospectively: special form was filled in for every patient participating in the study. Personal data, operation data, revision date, diagnosis and complications were recorded. Personal patient's identification number was used to determine the death date if it was present, and it was checked if the patient was operated on in other orthopedic centers. Study ended up on 31st of December, 2003. RESULTS: Total cumulative implant survival rate was 92% and 94% for revision because of aseptic loosening 10 years postoperatively. Stem survival was 95% for revision because of aseptic loosening. Cup survival was 94% for revision because of aseptic loosening. Implant type had no influence on survival rates. Dislocation rate after hip replacement was 10%. Mortality was 25% at the end of the follow-up. CONCLUSIONS: Total hip replacement after femoral neck fracture showed high implant survival and low additional surgery rate. Total hip replacement after femoral neck fracture was associated with high dislocation rate. Low patient's mortality rate was associated with relatively lower mean patient's age.

[Hip revision arthroplasty (long-term results)]. / Revizinis klubo sanario endoprotezavimas (velyvieji pooperaciniai rezultatai).

OBJECTIVE: To evaluate the risk factors after total hip replacement arthroplasty for rerevision and to analyze complications after hip revision surgery. MATERIAL AND METHODS: We obtained data from 117 hip revisions and 12 hip rerevision arthroplasties performed in 1992-2001 in the Department of Orthopedics of Klaipeda Hospital. Special forms were filled in for every patient who participated in the study. Name, operation date, type of implants, operative technique, revision diagnosis, intraoperative and postoperative complications were recorded. All patients were checked for death until 2003. RESULTS: Hip revisions were performed for 77 (66%) women and 50 (44%) men in 1992-2001. We revised 22 (19%) cups, 6 (5%) stems, 86 (74%) total hip revisions; femoral head was exchanged for 3 patients. Revision diagnoses were: aseptic loosening in 106 (90%) cases, recurrent dislocations in 7 (6%) cases, and periprosthetic fractures in 4 (4%) cases. Patients' age varied from 26-82 years, average 63.5 years. In revision group only 8% of patients were less than 50 years old, compared to 33% in rerevision group. Morselized allografts and bone impaction technique for reconstruction of bone defects were used in 70 (60%) of cases. We rerevised one cup only for which revision morselized allografts were used. Eight (67%) rerevisions were performed after first 28 (24%) hip revisions. CONCLUSIONS: Patients, who underwent revision surgery being younger than 50 years old, were at higher risk for rerevision surgery. Revision with morselized bone allografts and bone impaction technique decreases number of rerevisions. Learning curve was steep and had great influence to our results.