MRI Findings of Elbow UCL Tears in Baseball Players after Platelet-Rich Plasma (PRP) Therapy
Background
Platelet-rich plasma (PRP) therapy has been shown to be effective for treating ulnar collateral ligament (UCL) tears of the elbow of overhead throwing athletes. Magnetic resonance imaging (MRI) is the gold standard diagnosis tool for UCL tears. However, to our knowledge, there have been no studies that consider MRI evaluation after PRP therapy.
Methods
This case series included 61 baseball players (12 professional, 9 amateur, 32 college, 7 high school) who underwent PRP therapy for UCL tears of the elbow from December 2016 to March 2022. They were all recalcitrant to more than two months of rest and physical therapy. We excluded players who had a past history of UCL surgery. In all cases, MRI scans were taken before PRP therapy, and more than three months after PRP therapy (average 7.84 months). Images of UCL injury were classified into four grades by a musculoskeletal radiologist including, Grade 0 intact, 1 swelling, 2 incomplete tears, and 3 complete tears. The change in MRI grading pre- and post-PRP therapy was classified as ‘improved’, ‘no change’ or ‘deterioration’. Further, we analyzed the change of disability of the arm, shoulder, and hand (DASH) sports score and visual analog scale (VAS) score, categorized by the change of MRI grade. An ANOVA was used to compare the three groups.
Result: Of a total of 61 cases, 59 cases excluding duplicates were baseball players who underwent MRI evaluation pre-and post-PRP therapy. The change of MRI grade was 'improved' in 29 cases (49.2%), 'no change' in 26 cases (44.1%), and 'deterioration' in 4 cases (6.7%). The change of average DASH sport score from pre-PRP to post-PRP was 71.5 to 18.9, and the average VAS was from 52.4 to 13.2, respectively. The sample mean values (standard deviation) of MRI grade and DASH sports score pre- and post-PRP therapy was 51.6(6.4), 51.0(6.7), and 61.1(17.2) in the 'improved' , 'no change', and 'deterioration' groups, respectively (P = 0.49). The VAS score sample mean values (standard deviation) were 45.3(4.9), 37.7(5.2), and 25.0(12.3) for ‘improved’, ‘no change', and ‘deterioration' groups, respectively (P = 0.28).
Conclusion
Herein, PRP therapy for UCL injury affected the objective evaluation of MRI image findings after therapy. The subjective evaluation of DASH sports score and VAS was improved. These scores generally reflected MRI findings before, and after PRP treatment.