The initial stability of an exeter femoral stem after impaction bone grafting in combination with segmental defect reconstruction.
Bone impaction grafting of the femur is associated with more complications when segmental defects are present. The effect of segmental defect repair on initial stem stability was studied in an in vitro study with fresh-frozen goat femora. A standardized medial segmental defect was reconstructed using a cortical strut or a metal mesh. As controls, we used intact femora and femora with a nonreconstructed defect. In all 4 groups, impacted bone grafting was performed in combination with a cemented Exeter stem. Each group contained 5 femora. Reconstructions were dynamically loaded up to 1,500 N. Migration was measured with Roentgen stereophotogrammetric analysis. All cases with a nonreconstructed segmental defect failed into excessive varus rotation. None of the femora with a reconstructed defect failed. Cortical struts and metal meshes were equally effective in creating a stable stem construction (varus rotation, 2.89 +/- 2.27 and 2.27 +/- 0.57, respectively). Reconstructions with a metal mesh were more reproducible, although the obtained stability was significantly lower (P<.01) when compared with impaction grafting in an intact femur (varus rotation, 0.58 +/- 0.36).
Department of Orthopaedics, University Medical Center Nijmegen, Nijmegen, UK.
Stefan B T
SB
Bolder
B Willem
BW
Schreurs
Nico
N
Verdonschot
Robin S M
RS
Ling
Tom J J H
TJ
Slooff
D000818:Animals; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D016025:Bone Transplantation / Q000379:methods*; D001864:Bone Wires; D005269:Femur / Q000601:surgery*; D006041:Goats; D010780:Photogrammetry; D011475:Prosthesis Failure; D012086:Reoperation; D013249:Sternum / Q000637:transplantation*; D013526:Surgical Mesh; D016896:Treatment Outcome