OBJECTIVETo comparatively study the efficacy and safety of unilateral and bilateral balloon kyphoplasty in the treatment of painful multi-vertebral osteoporotic compression fractures.

METHODSFrom May 2002 to June 2007, 41 consecutive patients with painful multi-vertebral osteoporotic compression fractures underwent unilateral or bilateral kyphoplasty. The unilateral group included 3 male and 14 female with an average age of 70.4 (range 52 to 91 years old). The bilateral group included 4 men and 20 women with an average age of 72.4 (range 61 to 87 years old). Each procedure included insertion of inflatable balloon, fracture reduction and cement filling under "C"-arm monitoring. Preoperative and postoperative pain level, SF-36 score, radiographs and complications were recorded and analyzed.

RESULTSAll 41 patients tolerated the operation well. The mean operation time were (86 +/- 32) min and (120 +/- 26) min for unilateral and bilateral groups respectively; the mean volume of cement injected into one level were (3.9 +/- 1.6) ml and (5.4 +/- 2.1) ml for unilateral and bilateral groups respectively. The mean follow-up were (32.5 +/- 17.2) months and (30.7 +/- 14.3) months for unilateral and bilateral groups respectively. The mean VAS pain score of unilateral group decreased significantly from 7.4 +/- 2.1 preoperatively to 2.7 +/- 1.9 postoperatively (t = 2.50, P < 0.05) and 3.1 +/- 2.2 at final follow-up, the mean VAS pain score of bilateral group decreased significantly from 7.9 +/- 2.1 preoperatively to 2.3 +/- 2.5 postoperatively (t = 2.41, P < 0.05) and 2.7 +/- 2.2 at final follow-up, no significant difference was found between two groups. Significant increase of the mean height of anterior and medial vertebral body were recorded after the operation and maintained at final follow-up. The mean correction of local kyphosis was 7.2 degrees +/- 4.9 degrees for unilateral group and 7.3 degrees +/- 5.9 degrees for bilateral group, no significant difference was found between two groups. Postoperatively, 6 of 8 subscales measured by SF-36 were significantly improved for both groups. Complications were found in 7 patients including 6 cases of cement leakage and 1 case of pulmonary embolization.

CONCLUSIONAs a minimally invasive procedure, unilateral or bilateral kyphoplasty is effective and relatively safe for multi-vertebral osteoporotic compression fracture.