Hucheng Liu

Comparing the efficacy of short-segment pedicle screw instrumentation with and without intermediate screws for treating unstable thoracolumbar fractures

Abstract It is generally acknowledged that short-segment pedicle screw instrumentation is the preferred surgical method for thoracolumbar fractures. However, the use of short-segment instrumentation with or without intermediate screws at the fracture level remains controversial. We retrospectively evaluated 44 patients (28 men, 16 women) with unstable thoracolumbar fractures. The patients were divided into 2 groups according to the surgical method used. In group 1, 24 patients underwent surgery with a posterior approach via short-segment pedicle screw instrumentation (1 level above and 1 level below the fractured level). In group 2, 20 patients received an additional 2 screws at the fractured vertebrae. Clinical and radiologic parameters were evaluated before surgery and at 1 week, 6 months, and 1 year after surgery. We found no significant difference in the demographic characteristics between the 2 groups. No significant difference was observed in the operative time and intraoperative blood loss between the 2 groups. Clinical outcomes also showed no significant differences between the groups preoperatively or at all follow-up periods. The correction of the Cobb angle (CA) 1 week after surgery was better in group 2, whereas the anterior vertebral body height of the fractured level (AVHF) and compression ratio of the AVHF (AVHFCR) were not significantly different between the 2 groups 1 week after surgery. Moreover, group 2 had better maintenance of restored CA, AVHF, and AVHFCR at the fractured level than did group 1 at 6 months and 1 year postoperatively. In addition, the reduction of mid-sagittal diameter (MSD) of spinal canal 1 week and 1 year after surgery was better in group 2. Besides, bone fragments in the spinal canal have a tendency to be less in group 2 1 week and 1 year after surgery. Reinforcement with intermediate screws for a single thoracolumbar fracture not only enhanced the stability of the internal fixation system, but it was also conducive to the correction of kyphosis and the maintenance of the reduction effects. Furthermore, this method is helpful to restore the spinal canal and reduce the bone fragments in the spinal canal. However, more long-term follow-up studies are needed.

Inhibitory Effects of Lanthanum Chloride on Wear Particle-Induced Osteolysis in a Mouse Calvarial Model

Osteolysis is a bone disorder associated with progressive destruction of bone tissues. However, the effects of lanthanum chloride (LaCl3) on osteolysis remain unknown. Therefore, the aim of this study was to determine the effects of LaCl3 on osteolysis in vivo. In a mouse calvarial model, C57BL/6J mice were injected with wear particles with or without LaCl3. Microcomputed tomography, hematoxylin and eosin staining, and tartrate-resistant acid phosphatase staining were performed for the pathological characterization of calvariae, and eight calvariae per group were prepared for the assay of TNF-α, IL-1β, and RANKL secretion using quantitative enzyme-linked immunosorbent assay (ELISA). In mice treated with high-dose LaCl3, particle-induced osteolysis and inflammatory reaction were reduced compared with that in the vehicle-treated control. Moreover, treatment with high-dose LaCl3 suppressed the wear particle-induced decrease in bone mineral content, bone mineral density, and bone volume fraction. Bone destruction and resorption were higher in the LaCl3-treated group than in the saline-treated group but lower than those in the wear particle group. Finally, our results showed that treatment with a high dose of LaCl3 suppressed osteoclastogenesis. Thus, LaCl3 may represent a novel therapeutic agent for the treatment or prevention of wear particle-induced osteolysis and aseptic loosening.

Beclin-1 knockdown decreases proliferation, invasion and migration of Ewing sarcoma SK-ES-1 cells via inhibition of MMP-9

Although Beclin-1, a well-known key regulator of autophagy, has been demonstrated to serve a function in a number of disorders, including cancer, aging and degenerative diseases, its biological function in Ewing sarcoma (ES) remains unresolved. The objective of the present study was to determine the in vitro effect of Beclin-1 knockdown on the growth and malignant phenotype of ES SK-ES-1 cells, which have increased endogenous expression of Beclin-1 compared with RD-ES cells, and to investigate the underlying molecular mechanism. Cell proliferation, invasion and migration were investigated using CCK-8, Boyden chamber Transwell, and wound healing assays, respectively. Western blot analysis was used to detect expression levels of matrix metalloproteinase (MMP)-2 and MMP-9, which are associated with the malignant phenotype. Beclin-1 knockdown significantly inhibited proliferation, invasion and migration of SK-ES-1 cells. Western blot analysis revealed that Beclin-1 knockdown caused a significant reduction in the expression of MMP-9; no marked changes in MMP-2 expression were observed in the si-Beclin-1 group compared with the control group. The results of the present study suggest that Beclin-1 serves a function in proliferation, tumor progression and inhibition of autophagy in ES, and demonstrates its potential as a target to increase the efficacy of anticancer agents.

Therapeutic effect of neoadjuvant chemotherapy combined with curettage to treat distal femoral osteosarcoma: A case report

Rationale: Osteosarcoma is the most common malignant bone tumor in children and adolescents. Metastasis occurs early, the mortality rate is high, and the tumor results in a tremendous physical, mental, and economic burden on patients. Therefore, the treatment of osteosarcoma has been important for orthopedic surgeons. However, treatment has always been a difficult problem globally. Patient concern: We present the case of a 22-year-old girl with increasing local pain in the distal left thigh. Diagnoses: The patient was initially diagnosed as bone cancer according to computed tomography (CT) and X-ray imaging. And the patient was further diagnosed as osteosarcoma via to puncture biopsy of the left distal femur. Interventions: Local arterial infusion chemotherapy, systemic intravenous chemotherapy, and curettage was conducted because of limb salvage program. Outcomes: The patient was doing well with no evidence of local or distant recurrence 7 years after the surgery. Lessons: Our case indicated that limb osteosarcoma patients can undergo a limb salvage program of local arterial infusion chemotherapy, systemic intravenous chemotherapy, and curettage.