Objective:To summarize long-term clinical follow-up results of segment instability between the upper instrumented vertebra (UIV) and the adjacent upper vertebra (UIV+1) and to establish the optimal timing for surgery for UIV+1.Methods:A retrospective analysis was conducted on 265 patients with lumbar degenerative diseases who underwent transforaminal lumbar interbody fusion (TLIF) surgery at the Department of Spinal Surgery, Zhongda Hospital, from January 2014 to December 2018. The cohort included 119 male and 146 female patients, with an average age of 64.93 years (range: 32-86 years). Preoperative dynamic imaging measured sagittal angulation (SA) and sagittal translation (ST) of the UIV+1/UIV segment. Patients with SA>10° or ST>2 mm were categorized into the unstable group, further divided into the unstable non-fusion group and the unstable fusion group based on whether UIV+1 expansion fusion was performed. The remaining patients were classified into the stable group. Imaging indicators, Visual Analogue Scale (VAS) scores, Oswestry disability index (ODI) scores, and Japanese Orthopaedic Association (JOA) scores were compared among the groups, with JOA improvement rates calculated to assess clinical efficacy. Pearson correlation coefficient analysis was employed to examine correlations between preoperative imaging indicators and final follow-up JOA improvement rates. Receiver Operating Characteristic (ROC) curves and the maximum Youden index were utilized to determine thresholds for preoperative SA and ST.Results:The follow-up duration for all patients was 73.53±12.92 months (range: 61-108 months). The stable group (124 cases) included 61 males and 63 females, aged 64.31±9.83 years (range: 44-82 years). The unstable non-fusion group (59 cases) included 22 males and 37 females, aged 65.76±11.01 years (range: 32-86 years). The unstable fusion group (82 cases) included 36 males and 46 females, aged 65.26±8.68 years (range: 47-80 years). At the last follow-up, the unstable non-fusion group exhibited ΔSA 0.90°±1.97° and ΔST 0.77±1.27 mm, both significantly higher than the stable group's ΔSA 0.25°±1.57° and ΔST 0.34±0.34 mm ( t=3.564, P<0.001; t=2.311, P=0.022). Clinical improvements were lower in the unstable non-fusion group compared to the other two groups: VAS (2.28±0.83), ODI (5.91%±3.46%), JOA (24.11±1.78), with a JOA improvement rate of 60%. The stable group showed VAS (1.51±0.69), ODI (3.71%±1.75%), JOA (27.33±1.91), with a JOA improvement rate of 83%. The unstable fusion group had VAS (1.46±0.83), ODI (3.46%±1.81%), JOA (26.48±1.66), with a JOA improvement rate of 78%. These differences were statistically significant ( F=32.117, P<0.001; F=24.827, P<0.001; F=92.658, P<0.001; F=93.341, P<0.001). The JOA improvement rate was negatively correlated with preoperative SA ( r=-0.363, P<0.001) to a low extent, and with preoperative ST ( r=-0.596, P<0.001) to a moderate extent. ROC curve analysis determined the preoperative SA threshold as 11.5° and the preoperative ST threshold as 1.85 mm. Conclusion:Pre-existing instability of the responsible segment UIV and UIV+1 (SA>10° or ST>2 mm) may worsen during long-term follow-up after TLIF. When preoperative SA exceeds 11.5° and ST exceeds 1.85 mm between UIV and UIV+1, performing an extended fusion involving UIV+1 can ensure surgical efficacy over long-term follow-up.

Ex vivo culture-amplified mesenchymal stem cells (MSCs) have been studied because of their capacity for healing tissue injury. MSC transplantation is a valid approach for promoting the repair of damaged tissues and replacement of lost cells or to safeguard surviving cells, but currently the efficiency of MSC transplantation is constrained by the extensive loss of MSCs during the short post-transplantation period. Hence, strategies to increase the efficacy of MSC treatment are urgently needed. Iron overload, reactive oxygen species deposition, and decreased antioxidant capacity suppress the proliferation and regeneration of MSCs, thereby hastening cell death. Notably, oxidative stress (OS) and deficient antioxidant defense induced by iron overload can result in ferroptosis. Ferroptosis may inhibit cell survival after MSC transplantation, thereby reducing clinical efficacy. In this review, we explore the role of ferroptosis in MSC performance. Given that little research has focused on ferroptosis in transplanted MSCs, further study is urgently needed to enhance the in vivo implantation, function, and duration of MSCs.
Humans ; Antioxidants/metabolism* ; Ferroptosis ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stem Cells ; Iron Overload/metabolism*

OBJECTIVE: To review the clinical research progress of spinal epidural lipomatosis (SEL). METHODS: The clinical studies on SEL at home and abroad in recent years were extensively reviewed, and the pathogenesis, clinical and imaging manifestations, and treatment status of SEL were summarized and analyzed. RESULTS: SEL is a disease characterized by compression of the spinal cord and nerve roots due to abnormal accumulation of epidural adipose tissue in the spinal canal. Its prevalence and diagnosis rate are low and the pathogenesis is not fully understood. MRI is the most sensitive and specific diagnostic test for SEL. Surgical decompression and removal of excess adipose tissue are the only options for patients with acute SEL or those who have failed conservative management, and conservative management should be considered for other patients. CONCLUSION SEL is a rare disease and related research still needs to be improved. In the future, high-quality, multi-center and large-sample studies will be of great significance for evaluating the choice of treatment methods and effectiveness of SEL patients.
Humans ; Decompression, Surgical/methods* ; Epidural Space/surgery* ; Lipomatosis/surgery* ; Magnetic Resonance Imaging ; Spinal Cord Diseases/surgery*