OBJECTIVETo investigate the surgical options and clinical effects of delayed osteoporotic vertebral collapse.

METHODSFrom May 2010 to October 2014, 19 patients (20 vertebrae) with delayed osteoporotic vertebral collapse(Kümmell's disease) were enrolled in this study. There were 7 males and 12 females, aged from 65 to 87 years old with a mean of (73.5±5.62) years. According to Li staging system of Kümmell's disease, 3 cases were stage II, 13 cases (14 vertebrae) were stage III without spinal cord injury, 3 cases were stage III with spinal cord injury. Patients were respectively treated with percutaneous vertebroplasty(PVP) or percutaneous kyphoplasty(PKP) on the basis of the degree of postural reduction during operation. Injected cement volume, cement leakage, vertebral height restoration and local kyphotic reduction were observed. Visual analogue scale (VAS) and Oswestry Disability Index(ODI) were respectively used to assess the pain and function before and after operation. Frankel grade were used to evaluate neurological status.

RESULTSSeven vertebrae with satisfactory postural reduction were treated with PVP, 13 vertebrae with unsatisfactory postural reduction were treated with PKP, 3 patients with spinal cord injury were treated with decompression and posterior short segment fixation at the same time. All patients were followed up from 10 to 48 months with an average of 21.2 months. Cement leakage occurred in 4 cases with no symptom, 1 cases in PVP group and 3 cases in PKP group, there was no significant difference between two groups(=0.561). The priming volume of cement was (6.40±0.94) ml in PVP group and (5.46±1.09) ml in PKP group (>0.05). Three days after operation vs preoperation, the vertebral height restoration and kyphotic improvement was(31.71±11.35)%, (9.79±4.64)° in PVP group and (24.77±8.51)%, (8.15±2.97)° in PKP. There was no significant difference between two groups(>0.05). Three days after operation, VAS of low back pain and ODI in all patients were improved than preoperative data(<0.05), but there was no significant difference between two groups or between postoperative at 3 d and final follow up(>0.05). Nerve function of 3 patients underwent decompression and fixation from Frankel D to E.

CONCLUSIONSAccording to Li staging system and the degree of introperative postural reduction, individualized surgical treatment for Kümmell's disease can obtain good clinical results. Bad postural reduction during operation maybe a risk factor of cement leakage.