Cementless versus cemented Oxford unicompartmental knee arthroplasty: early results of a non-designer user group.
Although fewer tibial radiolucent lines are observed in cementless Oxford unicompartmental knee arthroplasty (UKA) compared with cemented Oxford UKA, an independent comparative study on this topic is lacking. In this multicentre retrospective study, a cohort of 60 consecutive cases of cementless Oxford UKA is compared with a cohort of 60 consecutive cases of cemented Oxford UKA. Radiolucent lines, survival, perioperative data and clinical results were compared. No complete tibial radiolucent lines were observed in either group. Seventeen per cent of partial tibial radiolucent lines were observed in the cementless group versus 21 % in the cemented group (n.s.). The percentage of tibial radiolucent zones was 4 versus 9 %, respectively (p = 0.036). Survival rates were 90 % at 34 months for the cementless group and 84 % at 54 months for the cemented group (n.s.). Mean operation time was 10 min shorter in the cementless group (p < 0.001), and clinical results were not significantly different. Although no significant differences in radiolucent lines were found between both groups, they appear to be more common in the cemented group. This confirms previous results from reports by prosthesis designers. The presence of radiolucent lines after cemented Oxford UKA does not correlate with clinical outcome or survival. III.