THE POSTERIOR CRUCIATE LIGAMENT IN TOTAL KNEE SURGERY - SAVE, SACRIFICE, OR SUBSTITUTE

To determine the role of the posterior cruciate ligament in total knee arthroplasty, 242 consecutive primary total knee arthroplasties were included in 1 of 3 sequential groups. Group I included 77 Press Fit Co ndylar total knee replacements in which the posterior cruciate ligamen t was completely released from its tibial attachment. In Group II, the re were 80 Press Fit Condylar total knee replacements in which the pos terior cruciate ligament was retained. Group III consisted of 85 total knee replacements with a posterior cruciate-substituting device (Insa ll-Burstein II). All patients were observed at least 2 Sears and evalu ated by the Knee Society's Clinical and Functional Scoring System, inc luding a radiographic evaluation. No differences were found between th e posterior cruciate ligament sacrificed group and the posterior cruci ate ligament preserved group. The 1 significant difference among the 3 groups was in range of motion (ROM). Groups I and II averaged 103 deg rees and 104 degrees motion respectively, whereas Group III, the poste rior cruciate-substituting group, averaged 112 degrees (p = 0.001). In addition, only in Group III was the lower 95% confidence limit of the mean ROM >90 degrees. These findings suggest that preserving the post erior cruciate ligament does not consistently lead to improved functio nal ROM. The posterior cruciate ligament-substituting device historica lly has demonstrated excellent survivorship and appears to offer great er ROM.