Objective To further investigate the possible mechanism of the correction of scol iosis with Staple by quantifying the effect of Staple on growth rate of vertebral growth plates in goat scol iosis. Methods Experimental scol iosis was created in 10 juvenile female goats by using unilateral pedicle screws asymmetric tethering. After 8-10 weeks, goats were divided randomly into Staple treated group (n=5) and control group (n=5). All tethers were removed in both groups and Staplegroup underwent anterior vertebral stapl ing with 4-5 shape memory alloy Staples along the convexity of the maximal curvature after posterior tether being removed. All goats were observed for an additional 8-13 weeks, the Cobb angle were measured to observe the correction of scol iosis. The fluorochromes Oxytetracycl ine and Calcein were administered respectively 18 and 3 days before death to label the ossifying front under the growth plates. Superior intervertebral disc of apical vertebra and two adjacent growth plates were completely harvested in all goats. All specimens were embedded with polymethyl methacrylate and sl iced undecalcified. The growth rates of the vertebral growth plates were calculated by measuring the distance between the two fluorescent l ines with fluorescence microscope. Results Nine (5 in Staple treated group and 4 in control group) of 10 tethered goats had progressive scol iotic curves of significant magnitude after 8-10 weeks of tethering. In Staple treated group, the Cobb angles were (34.8 ± 12.4)° at the instant after treatment , and (15.6 ± 11.7)° 8-13 weeks after treatment; showing statistically significant difference (P lt; 0.05). In the control group, the Cobb angles were (49.3 ± 18.0)° at the instant after treatment, and(49.0 ± 17.6)° 8-13 weeks after treatment; showing no statistically significant difference (P gt; 0.05). In Staple treated group, the growth rate of growth plate in the concavity (3.27 ± 0.96) μm/d was higher than that in convexity (1.84 ± 0.52) μm/d (P lt; 0.05), while the growth rate of the concavity did not differ significantly from that of the convexity in control group (P gt; 0.05). Conclusion Staple can significantly alter the growth rates of two sides of vertebrae in scol iosis with the growth rate of concavity exceeding the one of convexity, which results in correction of deformity.
Objective To compare the effectiveness of different puncture methods of the flexible bone cement delivery device in unilateral percutaneous curved vertebroplasty for osteoporotic vertebral upper 1/3 compression fractures. Methods A retrospective analysis was conducted on the clinical data of 67 patients with osteoporotic vertebral upper 1/3 compression fractures who were admitted and met the selection criteria between January 2023 and April 2024. The patients were divided into two groups based on the puncture method of the flexible bone cement delivery device: the oblique puncture group (n=37) and the parallel puncture group (n=30). There was no significant difference (P>0.05) between the two groups in terms of gender, age, bone mineral density (T value), distribution of fractured vertebrae, time from injury to operation, and preoperative visual analogue scale (VAS) score for pain, Oswestry disability index (ODI), anterior vertebral height of the fractured vertebra, and Cobb angle of the fractured vertebra. The following parameters were compared between the two groups: operation time, incidence of secondary puncture, incidence of bone cement leakage, volume of injected bone cement, bone cement distribution score, as well as VAS score, ODI, anterior vertebral height of the fractured vertebra, and Cobb angle of the fractured vertebra at 1 day after operation and at last follow-up. Results Two cases in the oblique puncture group and 7 cases in the parallel puncture group underwent secondary puncture during operation, and the difference in the incidence of secondary puncture was significant (P<0.05). No complications such as bone cement hypersensitivity, bone cement embolism, nerve injury, or epidural hematoma occurred in both groups. There was no significant difference in operation time, volume of injected bone cement, incidence of bone cement leakage, distribution score and rating of bone cement between the two groups (P>0.05). All patients were followed up 6-18 months (mean, 12.0 months), and there was no significant difference in the follow-up time between the two groups (P>0.05). No further fracture collapse or compression occurred in the fractured vertebra during follow-up. Both groups exhibited significant improvements in VAS score, ODI, anterior vertebral height, and Cobb angle of the fractured vertebra after operation compared to baseline (P<0.05). There were also significant differences between the two time points after operation (P<0.05). However, there was no significant difference in the above indicators between the two groups (P>0.05). Conclusion For osteoporotic vertebral upper 1/3 compression fractures treated with unilateral percutaneous curved vertebroplasty, both oblique and parallel puncture methods of the flexible bone cement delivery device can effectively relieve pain, but the former is more conducive to reducing the incidence of secondary puncture.
