The results of 26 cementless porous-coated anatomic (PCA) total knee arthroplasties (TKAs) were analyzed and compared to 25 cemented PCA TKAs. Identical prospective protocols were followed. The mean preoperative and postoperative knee scores at an average three-year follow-up interval (range, two to five years) were 59.6 and 81.5 for cementless knees compared to 57.6 and 80.4 for cemented knees. The difference was not statistically significant (p greater than 0.10). Blood loss was significantly higher in the cementless knees (p = 0.02). Radiolucent lines, loose beads, and tibial component subsidence were more frequent in cementless knees. No differences between cementless and cemented knees were observed in the femoral components. The PCA femoral components implanted without cement compare favorably to those implanted with cement. The PCA tibial and patellar components are more reliably secured with cement.