PCKP versus UPKP for moderate-to-severe osteoporotic vertebral compression fractures: a prospective randomized controlled trial revealing synergistic mechanisms of optimized bone cement distribution and anti-osteoporosis therapy on medium-to-long-term outcomes

Background Percutaneous curved kyphoplasty (PCKP) demonstrates early advantages in treating osteoporotic vertebral compression fractures (OVCFs), but its long-term efficacy and patient-selection criteria remain controversial. Objective The aim of this study is to prospectively compare the mid-to-long-term outcomes of PCKP versus unilateral percutaneous kyphoplasty (UPKP) for single-level OVCFs and establish a hierarchical decision model based on vertebral compression severity. Methods A total of 139 patients with single-level OVCFs (January 2021–January 2023) were randomized to PCKP (n = 67) or UPKP (n = 72), with ≥24-month follow-up. Outcomes included the visual analog score (VAS), Oswestry dysfunction index (ODI), cement distribution (type I–V classification), leakage rate, and re-fracture incidence. Anti-osteoporosis compliance was analyzed for its impact on efficacy. Results Both groups showed significant postoperative improvement in VAS and ODI ( p < 0.05). PCKP achieved superior early pain relief (VAS: 1.99 ± 0.77 vs. 3.47 ± 0.50; ODI: 27.07 ± 1.78 vs. 35.33 ± 3.12 at 2 days, p < 0.001), a higher cement distribution excellence rate (91.04% vs. 76.39%), and a lower leakage rate (10.45% vs. 26.39%). However, outcomes converged from 3 months onward ( p > 0.05), with no significant differences in re-fracture (11.94% vs. 15.28%) or anti-osteoporosis compliance (28.36% vs. 33.33%). Subgroup analysis revealed that PCKP provided more symmetric cement distribution ( p = 0.02) and a 21% lower leakage risk in moderate-to-severe OVCFs (Genant 2–3). Conclusion PCKP enhances early biomechanical stability in moderate-to-severe OVCFs through optimized cement dispersion, while long-term efficacy relies on standardized anti-osteoporosis therapy. A stepwise decision model (“PCKP for Genant 2–3, UPKP for mild cases”), combined with a “vertebral augmentation–bone metabolism modulation–behavioral intervention” strategy, is recommended.