A radiological analysis of uncemented PCA tibial implants with a follow-up period of 4-7 years.

A total of 63 uncemented PCA tibial implants were followed radiologically for a period of 4-7 years to establish whether primary fit, alignment, bone quality, age, and diagnosis have an effect on radiological results. Fifty-eight of the 63 tibial plateaus investigated (92%) showed excellent or good radiological results. In three cases the implant was rated radiologically endangered and in two cases radiologically loose. The results show that successful long-term anchorage depends principally on a primary stable fit. If implantation is inexact, poor bone quality, improper alignment, advanced age, and rheumatoid arthritis may be responsible for unsatisfactory radiological results. The authors conclude that particular importance must be attached to exact primary fixation when several unfavorable factors are encountered.