Platelet-Rich Plasma Content of Active Spinal Cord Injured Patients A Controlled Laboratory Study

Objective Platelet-rich plasma has potential uses for patients with spinal cord injuries. However, no study has quantified the cellular and growth factor content of platelet-rich plasma in this population. This study aimed to analyze (1) platelet-rich plasma content of spinal cord injury subjects and (2) the effect of high-intensity interval exercise on their platelet-rich plasma. Design Ten spinal cord injury patients and 10 controls were enrolled. At rest, platelet-rich plasma was created from both groups. The spinal cord injury group then performed high-intensity interval exercise and underwent a second blood draw to create post-high-intensity interval exercise platelet-rich plasma. Complete blood counts and growth factor analysis (via enzyme-linked immunosorbent assay) was performed on all platelet-rich plasma. Results The spinal cord injury group had lower platelets (305,700 +/- 85,697/mu l vs 380,800 +/- 57,301/mu l, P = 0.015) and transforming growth factor beta (12.84 +/- 1.58 vs 14.33 +/- 0.63 ng/ml, P = 0.023). Four minutes of high-intensity interval exercise increased the platelets (305,700 +/- 85,697/mu l to 399,200 +/- 96,251/mu l, P = 0.004), leukocytes (906 +/- 930 vs 2504 +/- 3765/mu l, P = 0.002) and transforming growth factor beta (12.84 +/- 1.58 to 14.28 +/- 1.21 ng/ml, P = 0.020). Conclusions Spinal cord injury patients have fewer platelets and transforming growth factor beta in their platelet-rich plasma at baseline compared with controls. Exercise increased platelet, leukocyte, and transforming growth factor beta yield, compensating for the baseline deficits.