Percutaneous vertebroplasty and percutaneous kyphoplasty for osteoporotic vertebral compression fractures: medium- and long-term evaluation of clinical outcomes and affecting factors

Although some studies have reported that patients with osteoporotic vertebral compression fractures (OVCFs) can benefit more from percutaneous kyphoplasty (PKP) than from percutaneous vertebroplasty (PVP), few large-sample, long-term follow-up studies have reported medium- to long-term clinical outcomes and the factors influencing the efficacy of PKP or PVP in the treatment of OVCFs. In this retrospective study, 622 patients with OVCFs received PVP, and 758 received PKP. All patients were followed up for at least 3 years. We compared patient data, including age, sex, body mass index (BMI), bone mineral density (BMD), surgical time, blood loss, polymethylmethacrylate (PMMA) dosage, complications, hospital stay, visual analogue scale (VAS), and Oswestry Disability Index (ODI). The radiographic outcomes included local Cobb angle and anterior vertebral body height (AVH) changes. Multiple linear regression analysis was performed to identify risk factors associated with the ODI in both groups, such as BMD, fracture segments, fracture severity, PMMA dosage, PMMA leakage, vertebral recollapse, old vertebral fracture, local kyphosis, adjacent vertebral fracture, and antiosteoporosis treatment. The VAS and ODI improved significantly in both groups before discharge and at 1 year ( P < 0.05) and then significantly increased at 3 years compared with those at 1 year post-operatively ( P < 0.05), but the difference between the two groups was not significant (P˃0.05). The mean PMMA dosage in the PVP group was significantly lower than that in the PKP group ( P < 0.05). The incidence rates of PMMA leakage and spinal impingement syndrome were greater in the PVP group than in the PKP group ( P < 0.05). The incidences of local kyphosis, adjacent vertebral fracture and vertebral recollapse in the PVP group were all significantly lower than those in the PKP group ( P < 0.05) at 3 years postoperatively. The postoperative local Cobb angle and AVH changes were significantly greater in the PKP group than in the PVP group ( P < 0.05). Multiple linear regression analysis revealed that the ODI was significantly associated with BMI, BMD, fracture segments, local kyphosis, vertebral recollapse, and anti-osteoporosis treatment ( P < 0.05) in both groups at the 3-year follow-up. Both PVP and PKP are effective at treating OVCFs, and the medium- and long-term clinical effects are similar. PVP has higher PMMA leakage and spinal impingement syndrome rates. PKP is more effective at restoring the local Cobb angle and AVH, but it is also associated with a higher incidence of local kyphosis, adjacent vertebral fracture and vertebral recollapse. For either PVP or PKP, high BMI, low BMD, multiple vertebral fractures, local kyphosis, vertebral recollapse and a lack of standardized anti-osteoporosis treatment were the main risk factors for a poor long-term ODI.