Validity and reproducibility of the PPLP scoring scale in the follow-up of athletes after anterior cruciate ligament reconstruction

Abstract

Objectives Validate the use of the PPLP scoring scale in the follow-up of athletes after anterior cruciate ligament (ACL) reconstruction. Patient and method We conducted a prospective follow-up study on athletes with ACL reconstruction during several time periods between 2003 and 2009, we analyzed the score validity, its reproducibility, its responsiveness to change and its relevance in the follow-up and monitoring of ACL reconstructive surgeries. Results The PPLP scoring scale was defined for the monitoring of ACL reconstruction in athletes. The PPLP tool is made of two parts: the first one (PPLP1) with a total of 100 points for postoperative follow-up and the second one also with a total of 100 points (PPLP2) adding up to the first score for determining a final post-op monitoring score of 200 points. The PPLP2 scoring scale is administered at a distance from the initial ACL reconstruction. For construct validity, we showed the differences in items’ characteristics (coefficient r of 0.20 in 763 patients), and adequate correlation of the PPLP score to other scoring scales found in the literature (OAK, Lysholm, Tegner, Knee injury and Osteoarthritis Outcome Score [KOOS], Arpege, IKDC Subjective Knee Evaluation Form and Psychovitality Test). The intra/interexaminer reproducibility is excellent going from 0.92 to 1. The PPLP scoring scale shows a statistically significant responsiveness to change during the hospital stay, according to the postoperative delay but with great variations. Complicated clinical evolutions (among 3296 ACL reconstructions with postoperative follow-up) are well identified by a low PPLP score, mainly for complex regional pain syndrome Type 1 (CRPS1: 1.9%) with a mean PPLP1 score of 80.33 whereas uncomplicated clinical evolutions (80.8%) have a mean score of 94.28 with a significant difference ( p < 0.0001). PPL2 scoring scale is significantly correlated to the possibility of getting back to competition ( p = 0.012) and a high score is linked to a faster return to competition (follow-up of 258 patients). The optimal threshold score is 176, and not 170/200, as previously suggested. However, this score remains poorly discriminating in regards to sensitivity (79.7%), specificity (49.3%) and the percentage of athletes returning to competition 2.5 months after completing the PPL2 scoring tool (37.9%). Conclusion The PPLP scoring scale was validated in the French language in terms of construct validity, reproducibility and sensitivity. This scoring scale is used for the follow-up and monitoring of ACL reconstruction in athletes, providing useful information on the quality of their recovery particularly during the postoperative phase and the possibilities of getting back to competition.