RESUMO
Background@#Pedicle screw augmentation with bone cement has been experimentally demonstrated to increase the pullout strength. However, the mechanisms of screw loosening are complicated and interacting. Although vertebroplasty augmentation and fenestrated screw augmentation have been compared in many studies, there has been no comparative study on their clinical effects and complications in real clinical settings. We investigated clinical effects of bone cement augmentation of a pedicle screw and differences according to augmentation methods. @*Methods@#Of the total 241 patients who had osteoporosis and underwent posterior pedicle screw fixation without anterior bone graft between January 2010 and December 2016, 132 patients with ≥2 years of radiological follow-up were included in this retrospective study. The patients were divided into group I (unaugmented) and group II (bone cement augmented). Group II was subdivided into II-S group (solid screw augmented) and II-F group (fenestrated screw augmented). The incidence of screw loosening was compared between groups I and II. Cement leakage, screw loosening, and screw fractures were investigated in the subgroups. @*Results@#In total, 36 of 71 (52%, group I) unaugmented cases and 96 of 170 (56%, group II) augmented cases were followed up for ≥2 years. Of the total 78 solid screw augmented cases, 42 (56%) were in II-S group; 54 of the total 92 (59%) fenestrated screw augmented cases were in II-F group. Groups I and II were homogenous regarding demographic characteristics; II-S and II-F groups were also homogenous. The incidence of screw loosening was 50.0% (18/36) in group I and 7.3% (7/96) in group II (p < 0.001). Cement leakage developed in 2 of 42 (4.8%) cases in II-S group and in 5 of 54 (9.3%) cases in II-F group (p = 0.462). Screw loosening developed in 6 of 42 (14.3%) cases in II-S group and in 1 of 54 cases (1.9%) in II-F group (p = 0.041). Screw fracture developed in none of 42 cases in II-S group and in 3 of 54 cases (5.6%) in II-F group (p = 0.254). @*Conclusions@#In osteoporotic patients, bone cement augmentation of a pedicle screw decreased the incidence of screw loosening, and fenestrated screw augmentation was more effective than vertebroplasty augmentation.
RESUMO
BACKGROUND: Spinal diseases are self-limited or non-progressive in many cases. Epidural steroid injection (ESI) is a common nonsurgical treatment option for spinal pain. Despite concerns about complications of repeated steroid injection, few studies reported on the adrenal function of spine disease patients undergoing surgery after ESI. We investigated the influence of preoperative multiple ESIs on adrenal function in spine surgery patients. METHODS: This was a retrospective study with prospective data collection. Those who underwent elective spinal operations and had a history of multiple ESIs from January to June 2017 were selected as a study group. Those who underwent knee arthroplasty and did not have a history of ESI and any kind of steroid injection in other areas during 6 months before surgery were selected as a control group. Demographic data were compared to assess homogeneity between groups. We assessed the preoperative serum cortisol level (SCL) to compare the basal adrenal function between groups. Also, we assessed the elevation of SCL postoperatively to evaluate the adrenal response to the surgical stress in each group. For subgroup analysis, we divided all patients into normal (7–28 µg/dL) and subnormal groups according to SCL and analyzed risk factors of adrenal suppression with multivariate logistic regression test. RESULTS: There were 53 patients in the study group and 130 in the control group. Age and sex were homogeneous between groups. There was significant intergroup difference in preoperative SCL (10.4 ± 4.8 µg/dL in the study group vs. 12.0 ± 4.2 µg/dL in the control group; p = 0.026).The postoperative day one SCL was 11.6 ± 5.0 µg/dL in the study group without significant increase from the preoperative level (p = 0.117), whereas the increase was significant in the control group with a postoperative level of 14.4 ± 4.4 µg/dL (p < 0.001). Among all patients, the SCL was subnormal in 18 patients and within the normal range in 165. Spine surgery was the independent risk factor irrespective of age and sex (odds ratio, 3.472; p = 0.015). CONCLUSIONS: Our results suggest that concern should be raised about the influence of preoperative multiple ESIs on adrenal suppression in spine surgery patients.