Poster 290: Effect of Platelet-rich Plasma Injections on Cartilage T1rho in Knee Osteoarthritis

Objectives: Platelet-rich plasma (PRP) injections have recently become commercially available and are marketed directly to consumers for the treatment of knee osteoarthritis (OA). Anabolic effects from cytokines concentrated in Leukocyte-Poor configurations PRP (LP-PRP) hypothesized inhibit native catabolic environment cartilage degeneration process. Multiple Level I trials comparing LP- hyaluronic acid placebo shown LP-PRP improve patient symptoms early OA up 1 year. However, it is unknown if changes due analgesic or clinical improvements biologic alteration natural course prevention progression. Quantitative magnetic resonance imaging (QMRI) sequences such as T1rho been reliable detection mapping with values increasing degree degeneration. The purpose this study 1) utilize delineate on setting mild moderate 2) determine correlated health after PRP. We hypothesize that will lead improved relaxation times at 6 months compared before treatment. Additionally, we improvement patient-reported 6- 12-months be times. Methods: Ten subjects [age: 52.9 years (range, 42 – 68 years); 9 female; BMI: 23.2 ± 1.9 kg/m 2 ; Kellgren- Lawrence (KL): Grade 1, n = 1; 2, 9] symptomatic unilateral were enrolled. Two patients lost follow-up 12-months. Exclusion criteria included BMI > 30 , prior surgery affected side, side (corticosteroid, acid, PRP, stem cells), end-stage (KL 3 4) any compartment knee, meniscus tear (flap, bucket handle, root tear), inflammatory arthropathy. Regenkit BCT was used make a standardized preparation injected into knee. Patient-reported outcome measures [Knee Osteoarthritis Outcome Score (KOOS) International Knee Documentation Committee (IKDC) score] administered injection 3-, 6-, injection. Sagittal maps (TR/TE 9.3/3.7 ms, time recovery 1500 FOV 36 cm, matrix 256 x 256, slice thickness 4 mm, spin-lock 0, 10, 40, 80 FSL 500 Hz) contralateral obtained baseline 6-months using 3T MRI scanner. Cartilage lesions graded Whole Organ Magnetic Resonance Imaging (WORMS). Articular semi-automatically segmented regions: lateral femur, tibia, medial patella, trochlea. regions without averaged each subject. Minimal important difference (MCID) calculated distribution based methods 0.5 standard deviation change. Kruskal-Wallis signed-rank test Spearman correlations performed. Significance set p < 0.05. Results: KOOS all subscales IKDC scores significantly 3-month follow- (all 0.05) sustained except sport subscale (p 0.051) (Figure 1). 75%, 87.5%, 62.5%, 100%, 87.5% exceeded MCID (pain, symptoms, ADL, sports, QOL) IKDC, respectively. At baseline, had higher WORMS lesion patellofemoral total joint (PF: 9.5 6.4 vs 7.0 6.5, 0.074; total: 15.9 15.3 11.9 15.4, 0.074) There no progression either In PRP- decreased 46.5 3.5 ms 43.7 0.036) 2). non-injected there significant change months. not associated Conclusions: This first QMRI. 6-month post-injection, lesions. As indirectly proteoglycan content cartilage, may suggest some healing. Interestingly, symptoms. Longer-term studies larger sample sizes needed further evaluate these relationships.