Subjective results of nonoperatively treated, acute, isolated posterior cruciate ligament injuries

Purpose: To evaluate subjective results obtained prospectively of patients who had acute isolated posterior cruciate ligament injuries. Type of Study: Prospective cohort study. Methods: Between 1983 and 2001, 271 patients who were seen for an acute, isolated posterior cruciate ligament (PCL) injury were asked to enroll in a long-term study (grade 1, n = 100; grade 1.5, n = 43; grade 2, n 128). Patients were evaluated using a modified Noyes subjective knee survey (mailed yearly), an activity survey (since 1998), and the International Knee Documentation Committee (IKDC) Subjective Knee Survey (since 2000). Results: The most recent modified Noyes survey was obtained from 215 patients at a mean time of 7.8 years after injury (range, I to 18 years), and the mean total score was 85.6 +/- 15.0 points. IKDC subjective scores were obtained from 85 patients at a mean time of 8.8 years after injury, and the mean score was 82.7 +/- 16.0 points. There was a statistically significant correlation between the IKDC subjective score and the modified Noyes total score (R-2 = .56426, P < .0001). Patients with greater PCL laxity did not have statistically significant lower subjective scores than patients with lesser PCL laxity. There were 146 patients who had at least 4 modified Noyes subjective surveys that could be evaluated for their consistency of total scores through time after injury. Total scores were consistently excellent for 40%, consistently good for 10%, consistently fair for 6%, consistently poor for 2%, consistently improving scores for 16%, decreasing scores for 12%, and inconsistent scores for 14%. Of 67 patients who scored less than 85 points in the first 2 years after injury, only 34 had a score of less than 85 points at their most recent survey. Conclusions: Subjective scores of patients with acute, isolated PCL injuries were independent of grade of PCL laxity and mean scores did not decrease with time from injury. No identifiable characteristics were identified that would help determine which patients with isolated PCL injuries would have deteriorating knee function.