THE ROLE OF THE POSTERIOR CRUCIATE LIGAMENT IN TOTAL KNEE ARTHROPLASTY

Abstract

129 knees suitable for a standard PCL retaining cemented total knee replacement were randomised into two groups, one in which PCL was retained in the normal way, the other group having the PCL fully resected. Both groups received a PCL retaining implant. The two groups were well matched with a predominance of females and a mean age of 67 years.

There was no statistically significant difference in the HSS scores at an average of 57 months (range 56–60 months) in the two groups. Pain relief, deformity correction, range of motion, stability and strength were comparable in the two groups. A radiological assessment revealed femoral rollback in approximately 20% of cases with a slightly higher incidence in the PCL sacrificed group. There was no significant loosening detected in either of the categories at two years review.

At five years one TKR in the PCL retained group has been revised due to an infection and one each in the two groups are awaiting revision surgery for loosening. Our findings have shown that there is no significant difference in the 5 year results of a PCL-retaining total knee replacement if the PCL is excised or preserved. This suggests two significant points:

1. the PCL is not functional in most patients with a total knee replacement even when retained:

2. patients with excised PCLs show good results with PCL retaining implants, thereby questioning the need for posterior stabilised designs in all such cases.