Establishment of an animal model of adjacent segment degeneration after interbody fusion and related experimental studies.

BACKGROUND: Degenerative spine conditions are common and frequent clinical diseases, and adjacent segment disease (ASD) after spinal fusion (SF) is a common complication after spinal fusion (SF). In this study, we established an animal model of ASD after interbody fusion to observe the morphologic changes of adjacent segment (AS) disks and to determine the expression and significance of tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1ß) in ASD tissues to provide a good experimental basis and reference for clinical prevention and treatment of ASD after interbody fusion. METHODS: Thirty-six male and female New Zealand rabbits weighing 2.0-2.5 kg were randomly divided into control group (group A) and experimental groups (groups B, C, and D), with 9 rabbits in each group, of which groups B, C, and D were the 4-, 8-, and 12-week groups, respectively. Autologous iliac bone grafts were used as the bone graft material. In the experimental groups, a SF was performed on the C2-C3 intervertebral space. The C3-4 adjacent segments were examined. In the experimental group, the animals were subjected to gross observation, X-ray examination, hand touch inspection, and micro-computed tomography (micro-CT) 4, 8, and 12 weeks after surgery. The micromorphologic changes of the cervical disks in the segments of the control group and experimental groups were observed under light microscopy. Immunohistochemistry and Western blotting were used to detect the expression of TNF-α and IL-1ß in the AS tissues after interbody fusion in the control and experimental groups. RESULTS: The measurement data of the rabbit cervical spine bony structures indicated that the length of the vertebral body and the sagittal diameter of the lower end of the vertebral body decreased gradually from the 2nd-6th cervical vertebrae, and the difference was statistically significant (P < 0.05). The difference in the transverse diameter of the lower end of the vertebral body was not statistically significant (P > 0.05), the change in the oblique diameter of the lower end of the vertebral body fluctuated, and the difference was statistically significant (P < 0.05). The fusion rate of the cervical spine by hand touch inspection was 22.2% (2/9), 55.6% (5/9), and 88.9% (8/9) in groups B, C, and D, respectively. The differences in bone volume-to-total volume (BV/TV) and X-ray scores were statistically significant in groups B, C, and D (P < 0.05). Significant degeneration occurred in groups B, C, and D compared with group A. The expression of TNF-α and IL-1ß in the intervertebral disk tissue was significantly higher in groups B, C, and D compared with group A (P < 0.05), and increased with time. CONCLUSION: In this study, an animal model of ASD after interbody fusion fixation in rabbits was successfully established. Postoperative imaging and hand touch inspection showed a positive correlation between the amount of new intervertebral bone and the degree of fusion with time. The results of immunohistochemistry and Western blot showed that TNF-α and IL-1ß were highly expressed in the AS tissues of the experimental group after interbody fusion, and the degree of disk degeneration was positively correlated with the time after interbody fusion.

The Efficacy of Scouting Technology in Pedicle Screw Placement in the Patients With Degenerative Scoliosis.

Objective: To investigate the curative effect of ball tip technology in pedicle screw placement in the patients with degenerative scoliosis (DS), as compared to traditional freehand technique. Methods: A total of 90 patients with degenerative scoliosis who were admitted to Affiliated Hospital of Hebei Engineering University from October 2019 to October 2021 were selected as the objects in this prospective study. They were randomly divided into an experimental group and a control group with 45 cases in each. The clinical indications, the accuracy of pedicle screw placement, the occurrence of surgical complications, the measurement of spinal and pelvic parameters, the recovery of spinal function and pain degree were recorded and compared within the two groups. Results: After treatment, the operation time, intraoperative blood loss, total number of screws, and time of screwing were compared between the two groups, and the difference was not significant (P > .05). However, the bedding time and the hospital stay were shorter in the experimental group than the control group with difference (P < .05). There was no significant difference in clinical standards and poor implantation in the Gertzbein-Robbins A-E classification between the two groups (P > .05). While the number of perfect placement of screws in the experimental group was higher (P < .05). Before treatment, the Cobbs angle and pelvic incidence-lumbar lordosis (PI-LL) levels of the two groups were comparable (P > .05); after treatment, the Cobbs angle and PI-LL levels of the two groups were lower than those before treatment, and the difference was significant (P < .05). There was no significant difference in Cobbs angle and PI-LL levels between groups (P > .05). Before treatment, the JOA and DOI scores of the two groups were comparable (P > .05); after treatment, the JOA and DOI scores of the two groups were improved (P < .05); the improvement of JOA and DOI scores of the experimental group were better than those in the control group (P < .05). Before treatment, there was no significant difference in the pain degree between the two groups (P > .05); after treatment, the pain of the two groups was improved compared with that before treatment, and the pain degree of the experimental group was lower than that of the control group (P < .05). The incidence of postoperative complications in the experimental group was lower than that in the control group, but there was no significant difference in the total incidence of postoperative complications between the two groups (P > .05). Conclusion: The scouting technique-assisted screw placement can effectively improve the spinal function of patients with degenerative scoliosis, with obvious curative effect and high safety.

Effects of full-threaded headless cannulated compression screws and anatomical plates on the efficacy, safety, and prognosis of patients with triplane fractures of the distal tibia.

OBJECTIVE: To compare the clinical efficacy, safety, and prognosis of full-threaded headless cannulated compression screws (HCCSs) and anatomical plates (APs) in the treatment of triplane fractures of the distal tibia. METHODS: In this retrospective study, 74 patients with triplane fractures of the distal tibia treated in our hospital from April 2017 to March 2019 were selected as the research subjects. Among them, 38 patients receiving full-threaded HCCSs were assigned to the research group (RG), and the remaining 36 patients receiving APs were assigned to the control group (CG). The general indices, including operation, fracture healing, and ambulation times, efficacy, and complications were recorded and compared between the two groups. Visual analogue scale (VAS) was applied to assess pain, and a quality of life (QOL) survey was conducted at 6 months after surgery. RESULTS: Compared with the CG, the operation time, fracture healing time, and ambulation time of the RG were significantly shortened (P<0.05). The proportion of patients with excellent and good outcomes and Mazur Scores in the RG were higher than those in the CG (P<0.05). The frequency of complications in the RG was lower than that in the CG (P<0.05). The preoperative VAS score did not exhibit significant differences between the two groups (P<0.05), but the scores in the RG at T1 and T2 were significantly lower than those in the CG (P<0.001). The QOL score in the RG (76.17±8.57) was also significantly higher than in the CG (71.54±8.02) (P<0.05). CONCLUSION: Full-threaded HCCSs are more effective and safer than APs and can effectively improve the prognosis of patients with triplane fractures of the distal tibia.

Quantitative Evaluation of Compressed L4-5 and S1 Nerve Roots of Lumbar Disc Herniation Patients by Diffusion Tensor Imaging and Fiber Tractography.

OBJECTIVE: To delineate fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of compressed nerve roots in patients with lumbar disc herniation by diffusion tensor imaging and fiber bundle tracing and investigate the relationship between FA and ADC values and Swiss Spinal Stenosis Questionnaire and visual analog scale scores. METHODS: Twenty patients with lumbar disc herniation and 20 age- and sex-matched healthy volunteers were assessed using the Swiss Spinal Stenosis Questionnaire and visual analog scale. All subjects underwent conventional sagittal T1-weighted and T2-weighted magnetic resonance imaging, axial T2-weighted imaging, and diffusion tensor imaging and fiber tractography. RESULTS: In 20 patients with lumbar disc herniation, there were 31 nerve roots involved (9/31 L4, 15/31 L5, and 7/31 S1). Mean Swiss Spinal Stenosis Questionnaire scores of patients were 53.55% ± 11.91%, and mean visual analog scale scores were 5.96 ± 1.64. FA values of lumbar nerve roots were 0.332 ± 0.014 in healthy volunteers. FA values of compressed lumbar nerve roots were 0.251 ± 0.022, significantly lower than FA values of contralateral noncompressed nerve roots and lumbar nerve roots of healthy volunteers. ADC values of lumbar nerve roots were 1.763 ± 0.075 in healthy volunteers. ADC values of compressed lumbar nerve roots were 2.090 ± 0.078, significantly higher than ADC values of contralateral noncompressed nerve roots and lumbar nerve roots of healthy volunteers. CONCLUSIONS: Fiber tractography is capable of delineating microstructural changes of lumbosacral nerve roots, and radiculopathy in lumbar disc herniation is associated with significant changes in FA and ADC values.