Abstract
Introduction: Periprosthetic fractures occurring during implantation of non-cemented Total Hip Arthroplasty (THA) are considered major surgical complications. As a shot-term disadvantage, patients are required to partially weight-bear. Additionally, high risks of stem migration and joint luxation can be assumed. On the other hand, in fear of fracture surgeons may undersize stems and subsequently trigger failure rates in THA.
As the long-term consequences of Vancouver A and B1 fractures are not fully known, the goal of this study now was to analyze the postoperative performance of non-cemented THA with respect to perioperative fractures.
Materials and Methods: Between 1997 and 2003 41 peri-operative hip fractures were monitored in 1216 primary Total Hip Arthroplasties using the non-cemented Bicon-tact THA stem. Pre-OP and after a follow-up period of 2,2 (+−3,1) years patients were examined clinically and radiographically. Investigation parameters were Harris-Hip-Scores, SF-36 scores, function score, hospitalization, implant survival /revisions and radiographic parameters (stem migration, trochanter migration, osteolysis, bone union, callus formation and bone quality). Fractures were graded using the Vancouver and Mont+Maar classifications. Patients were compared to a comparable collective of THA patients without perioperative fractures. Pooled data of both groups were compared using non-parametric Kruskal-Wallis tests.
Results: Results showed a significant increase in Harris-Hip scores for all THA of 36 (+−17,7) points. There were no differences in function scores (2,3; score 1–6), postoperative pain (4,8; score 1–10), and time of hospitali-sation (21,3d; +−3,7 range, 14 – 32). The non-union rate was 13%, with 85% of trochanteric fractures showing migration. 47% of the Patients in the fracture group were instructed to maintain restricted weight bearing for 6 weeks. No Trendelenburg signs were observed in the fracture group. Stem migration of mean 0,6 cm (+−0,4) was observed in 13% of Vancouver A and B1 patients (6,4% of A, 20,1% of B1). Long-term cerclage wire failure was observed in 20%. Joint luxation was observed in 1 patient. No hips were revised during the follow-up period.
Discussion: Follow-ups of perioperative fractures classes Vancouver A and B1 during non-cemented THA using the Bicontact stem show associations with stem migration, long-term stabilization implant failure and non-union. However, none of these observations seem to be influencing the overall THA performance and patient satisfaction. Specifically, complications commonly associated with perioperative primary prosthetic fractures as luxation and limping were not signifi-cant. At a short-term perspective, perioperative THA fractures prohibit early weight-bearing. However at a mid to long-term perspective, no disadvantages were apparent in comparison to primary THA without fracture complications.
Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
