Clinical Studies on Posterior Cruciate Ligament Tears Have Weak Design

Very few studies in the literature focus on isolated PCL injury. Recent studies are in general more optimistic with regard to the results than previous reports. There are few randomized controlled trials and few prospective comparative studies, which may limit the value of the reported results. The goal of the present study was to evaluate the methodology of published studies according to a well-established scoring system. Studies with a high success rate have a low score on methodology design. This study was based on systematic review and level 3 evidence. We performed a literature search and included studies in which the primary aim was to report the outcome after management of isolated PCL injury. The quality of the studies was evaluated using a modified Coleman methodology score, which results in a score between 0 and 100. Studies were also assessed with use of level-of-evidence rating. We collected data on the year of publication, reported results after surgery and conservative treatment, and the outcome scales used to assess the results. Forty studies were included. The average methodology score was 52. No significant difference in outcome was detected between conservative and surgical management. Our hypothesis that a low Coleman score would yield a good clinical result was not verified. This could be caused by the fact that there were very few studies with a high Coleman score. The Coleman methodology score correlated positively with the year of publication and with the level-of-evidence rating. In the 40 reported studies, 12 different outcome scales were used. In conclusion, the generally low methodological quality shows that caution is required when interpreting results after management of injury to the PCL. Firm recommendations on what treatment to choose cannot be given at this time on the basis of these studies. More attention should be paid to methodological quality when designing, conducting and reporting trials.