MRI Clues Link Injury Patterns to Complete PCL Tear Location

The team reviewed MRI scans to map where complete posterior cruciate ligament, or PCL, tears occurred and to see which patient or injury features were linked to each location. The review covered one medical center and cases treated from 2008 through 2023. Only recent, fully disrupted PCL injuries were eligible. Cases with sprains but no ligament break, partial tears, or injuries older than 60 days were excluded.

There were 148 eligible MRI scans. The average age was 36 ± 16 years, and women made up 33% of the group. The tears were sorted by the amount of distal ligament still present: type I had more than 90% remaining, type Ib involved a femoral bony avulsion, type II had 90% to 75% remaining, type III had 75% to 25%, type IV had 10% to 25%, type V had less than 10%, and type Vb involved a tibial bony avulsion. Type III was the most common pattern at 43.2%. Type I followed at 18.9%, type IV at 15.5%, and type Vb at 11.5%. Types Ib, II, and V appeared in 4.1%, 3.4%, and 3.4% of cases. Reviewers showed very strong agreement on the categories, with κ = 0.96, a 95% confidence interval of 0.93 to 0.99, and P < .001.

The women were older than the men on average, at 41.6 ± 16.3 years compared with 32.7 ± 14.6 years. Direct contusion injuries were also more common among women, appearing in 44.4% of their cases versus 27.0% of men’s cases. Cutting-sports injuries showed the opposite pattern, occurring in 2.3% of women and 23.6% of men. Those numbers make the injury setting worth considering when a PCL tear is being evaluated.

Four factors were independently linked to proximal PCL tears, which include types I, Ib, and II. These were multiligament injury, with an odds ratio of 8.2 and a 95% confidence interval of 2.9 to 26.5; a hyperextension-type bone bruise pattern, with an odds ratio of 8.1 and a 95% confidence interval of 2.5 to 28.9; a medial meniscus tear, with an odds ratio of 6.9 and a 95% confidence interval of 2.4 to 21.6; and younger age, with an odds ratio of 0.96 for each additional year. All three reported predictors had P < .001.