Correlation of kyphosis and wedge angles with outcome after percutaneous vertebroplasty: a prospective cohort study.

PURPOSE To evaluate the correlation of kyphosis and wedge angles with pain relief and functional outcome after percutaneous vertebroplasty (PV). METHODS 15 men and 19 women aged 41 to 85 (mean, 62) years who presented with osteoporotic wedge compression fractures of the dorsolumbar spine below T5 and had failed conservative treatment were included. Patients were assessed before and one year after PV. Kyphosis and wedge angles were measured on standardised radiographs. Pain and function were assessed using the visual analogue scale (VAS) score and the Ronald Morris Disability Questionnaire (RMDQ) score, respectively. Patients were dichotomised based on their preoperative kyphosis (≤ 10 vs. >10 degrees) and wedge angles (≤ 7 vs. >7 degrees). Outcomes were classified as excellent, fair, and poor in terms of VAS scores (<3, 3-6, >6) and RMDQ scores (<8, 8-16, >16). Correlations between the kyphosis and wedge angles and VAS and RMDQ scores were assessed. RESULTS VAS and RMDQ scores correlated positively with the kyphosis and wedge angles; the highest correlation was between the VAS score and kyphosis angle (r=0.93). A significantly greater proportion of excellent outcomes (in terms of RMDQ and VAS scores) were noted in patients with preoperative kyphosis and wedge angles of ≤ 10 and ≤ 7 degrees, respectively. CONCLUSION PV is a viable treatment for vertebral compression fractures with regard to pain relief and improvement of function. Preoperative kyphosis and wedge angles were predictive of post-PV outcomes in terms of VAS and RMDQ scores.