Revision Arthroplasty of
the Knee with Allograft Bone
Allan E. Gross, M.D.,
F.R.C.S.(C) Head, Division of
Orthopaedic Surgery Mount Sinai Hospital Professor of Surgery,
Department of Surgery University of Toronto Toronto, Ontario Bone defects in revision arthroplasty of the
knee can be classified as contained or uncontained. Uncontained defects can be non-circumferential or
circumferential. The surgical options
for managing these defects are; implant supplements, tumour prostheses, or
bone grafts (allograft). Contained defects on both the tibial and femoral sides can be managed
by impacted morsellized allograft bone in conjunction with stemmed
components. Small contained defects
in the low demand patient can be simply managed by more cement, with or
without reinforcement by screws. Small to moderate sized uncontained defects
can be managed by implant supplements on both the femoral and tibial
sides. On the femoral side implant
supplements of 1 cm can be added distally and 1 cm posteriorly. On the tibial side, implant supplements of
up to 3 cms are available. In
addition the poly insert can add another 3 cms. Larger uncontained defects can be managed by
tumour prostheses or structural allografts in conjunction with stemmed components. The structural allografts are fixed by
cancellous screws to the host bone and further fixation was provided by the
long stem of the prostheses. For
long, full circumferential grafts we use a step-cut of the graft and host bone
at the junctions and cerclage wiring.
Cement was used for the interface between allograft and implant, and
between the implant and host bone on the surface, but not between the stem
and host bone. Suggested Reading: 1. Ghazavi
MT, Stockley I, Yee G, et al:
Reconstruction of massive bone defects with allograft in revision
total knee arthroplasty. J. Bone
Joint Surg; 79-A:17-25, January 1997. 2. Stockley
I, McAuley JP, Gross AE: Allograft
reconstruction in total knee arthroplasty.
J. Bone Joint Surg; 74-B:393-97, 1992  Previous
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