Determination of Effect of Platelet Rich Plasma Injection on Improving Pain and Function in Young Healthy Athletes with Isolated Grade 2 or 3 Knee Medial Collateral Ligament Sprains

Knee medial collateral ligament (MCL) sprain is common in athletes, which keeps them away from trainings. Platelet-rich plasma (PRP) injection is used as an adjunct for treatment of musculoskeletal injuries. This study was supposed to define effect of PRP injection on high-grade MCL sprain healing, in comparison to rehabilitation alone. This study was performed on 46 healthy athletes with high-grade MCL sprains who came to sports medicine clinic of Taleghani Hospital, Tehran over a one-year period (2017-2018). In first visit injury grade, its location, baseline pain, Lysholm score and joint stability was determined. Participants randomly allocated to 2 groups (n=23), “group A” had 12-week functional rehabilitation and “group B” had the same rehabilitation plus a single PRP injection. At 4-week intervals valgus stress testing, pain and Lysholm scores was reassessed. The scores of 4th, 8th and 12th weeks was compared to the baseline scores. Mean baseline pain score in control and intervention group was 5.09±0.949 and 5.26±0.810 respectively that in the fourth week of study reduced to 1.30±0.765 and 2.43±0.507 (p<0.001). In intervention group, fourth week pain was significantly reduced while stability and Lysholm scores of the groups had no significant difference. PRP injection had a short-term statistically significant pain reduction effect that may assist in faster rehabilitation progress, shorter return to play and less detraining which is crucial to professional athletes.