Comparison of peri-prosthetic bone density in cemented and uncemented total knee arthroplasty.

The aim of our study was to assess the effect of knee replacement with or without bone cement on periprosthetic bone density. Periprosthetic bone density in two comparable groups (30 each) of cemented and uncemented knee replacements was measured with DEXA scanner. Bone loss was more in the area posterior to the anterior femoral flange in the cemented subgroup, nearing statistical significance (p = 0.059). In both groups, the reported bone density at a median of four years postoperatively was reduced at several periprosthetic sites. However, the method of fixation could not be clearly demonstrated to influence the bone loss differentially. This brings into question the use of the more expensive cementless implants. Reduction in bone density in both groups at several periprosthetic sites remains a concern. Whether or not this can be addressed with medical intervention like post arthroplasty bisphosphonate treatment needs further consideration.