Effects of unilateral and bilateral diffusion of cement on osteoporotic vertebral compression fractures treated with percutaneous kyphoplasty / 中华创伤杂志

ABSTRACT

Objective To evaluate the effects of unilateral and bilateral diffusion of cement on osteoporotic vertebral compression fractures treated with percutaneous kyphoplasty (PKP). Methods A retrospective case control study was conducted on the clinical data of 127 patients with single segment osteoporosis vertebral compression fracture (OVCF) treated by unilateral puncture PKP between July 2013 and July 2015. According to whether the diffusion of bone cement crossed the median, all cases with OVCF were divided into unilateral and bilateral diffusion groups. The unilateral diffusion group (72 cases) included 29 males and 43 females, with an average age of 69.5 ± 2.6 years (range, 63-76 years). In terms of the injured segment, there were 38 cases of L1, 20 L2, 11 L3, two L4, and one L5. In the unilateral diffusion group, the preoperative visual analog score (VAS) was (7.8 ±0.9) points, the preoperative anterior vertebral height compression ratio was (32.5 ±6. 3)％, and the preoperative Cobb's angle of the injured vertebra was (9.2±1.3)°. The bilateral diffusion group (55 cases) included 22 males and 33 females, with an average age of 71.2 ±2.9 years (range, 61-80 years). In terms of the injured segment, there were 32 cases of L1, 13 L2, six L3, three L4, and one L5. In the bilateral diffusion group, the preoperative VAS was (7.6 ±0. 9)points, the preoperative anterior vertebral height compression ratio was (34.5 ±5.8)％, and the preoperative Cobb's angle of the injured vertebra (9.8± 1.5)°. The VAS, anterior vertebral height compression ratio of the injured vertebra, Cobb's angle of the injured vertebra, and injured and non-injured vertebra refracture 1 month and 1 year after operation were recorded. Results The patients were followed up for 12-16 months (mean, 14.6 ± 0.6 months) in unilateral diffusion group and for 13- 16 months (mean, 15.2 ±0.2 months) in bilateral diffusion group. The VAS score of the unilateral diffusion group was (3.0 ±0.4) points at 1 month after the operation and (2.2±0. 4) points at 1 year after the operation, respectively. The VAS score of the bilateral diffusion group was (2.1 ±0.4) points at 1 month after the operation and (1.5 ± 0.4) points at 1 year after the operation, respectively. The VAS score decreased significantly 1 year after operation compared with that before operation (P ＜0.05), and significant difference was noted between two groups (P ＜0.05). The anterior vertebral height compression ratio of the unilateral diffusion group was (15.2±3.9)％ at 1 month after the operation and (16.3 ±3.4)％ at 1 year after the operation, respectively. The anterior vertebral height compression ratio of the bilateral diffusion group was (15.6±3.5)％ at 1 month after the operation and (16.8 ±3.9)％ at 1 year after the operation, respectively. The Cobb's angle of the injured vertebra of the unilateral diffusion group was (2.9±0.7)° at 1 month after the operation and (3.0±0.6)°at 1 year after the operation, respectively. The Cobb's angle of the injured vertebra of the bilateral diffusion group was (3.0 ± 0.7) ° at 1 month after the operation and (3.2 ± 0.7) ° at 1 year after the operation, respectively. The anterior vertebral height compression ratio and Cobb's angle of the injured vertebra decreased significantly after surgery (P ＜ 0.05), but no statistically significant differences were observed between two groups (P＞0.05). The injured vertebra refracture ratio was 6.9％ in unilateral diffusion group and 0 in bilateral diffusion group. The non-injured vertebra refracture ratio was 5.6％ in unilateral diffusion group and 5.5％ in bilateral diffusion group. No nerve root injury, cerebrospinal fluid leakage, pulmonary embolism, anaphylactic shock and postoperative infection were found in the two groups. Paravertebral bone cement leakage occurred in two cases of the unilateral diffusion group and anterior vertebral bone cement leakage occurred in one case of the bilateral diffusion group. Conclusion Compared with unilateral diffusion, bilateral diffusion of bone cement has better analgesic effect and can reduce the incidence of re fracture of injured vertebra, without increasing the risk of re-fracture of the non-injured vertebrae.