Platelet-rich plasma enhances bone union in posterolateral lumbar fusion: A prospective randomized controlled trial

Background Context Platelet-rich plasma (PRP) accelerates bone union in vivo in a rodent model of spinal fusion surgery. However, PRP's effect on bone union after spinal surgery remains unclear. Purpose The objective of this study was to evaluate the efficacy of PRP after posterolateral lumbar fusion (PLF) surgery. Study Design/Setting Single-center prospective randomized controlled clinical trial with 2-year follow-up. Patient Sample The patient sample included a total 62 patients (31 patients in the PRP group or 31 patients in the control group). Outcome Measures The outcome measures included the bone fusion rate, the area of bone fusion mass, the duration of bone fusion, and the clinical score using the visual analog scale (VAS). Materials and Methods We randomized 62 patients who underwent one- or two-level instrumented PLF for lumbar degenerative spondylosis with instability to either the PRP (31 patients) or the control (31 patients) groups. Platelet-rich plasma-treated patients underwent surgery using an autograft bone chip (local bone), and PRP was prepared from patient blood samples immediately before surgery; patients from the control group underwent PLF without PRP treatment. We assessed platelet counts and growth factor concentrations in PRP prepared immediately before surgery. The duration of bone union, the postoperative bone fusion rate, and the area of fusion mass were assessed using plain radiography every 3 months after surgery and by computed tomography at 12 or 24 months. The duration of bone fusion and the clinical scores for low back pain, leg pain, and leg numbness before and 3, 6, 12, and 24 months after surgery were evaluated using VAS. Results Data from 50 patients with complete data were included. The bone union rate at the final follow-up was significantly higher in the PRP group (94%) than in the control group (74%) (p=.002). The area of fusion mass was significantly higher in the PRP group (572 mm2) than in the control group (367 mm2) (p=.02). The mean period necessary for union was 7.8 months in the PRP group and 9.8 months in the control group (p=.013). In the PRP, the platelet count was 7.7 times higher and the growth factor concentrations were 50 times higher than those found in plasma (p<.05). There was no significant difference in low back pain, leg pain, and leg numbness in either group at any time evaluated (p>.05). Conclusions Patients treated with PRP showed a higher fusion rate, greater fusion mass, and more rapid bone union after spinal fusion surgery than patients not treated with PRP.