Currently, the common treatment for femoral nonunion with large segmental bone defect is difficult and complex. The effective surgical methods are rare, include vascularized bone grafting, Masquelet technique and Ilizarov distraction osteogenesis. The objective of this study is to investigate the outcomes of segmental femoral defects treated with monolateral external fixation using the distraction osteogenesis. We retrospectively analyzed patients with femoral nonunion with segmental bone defects (> 6 cm) between January 2010 and January 2014 in our single trauma center. All patients were treated by distraction osteogenesis with monolateral external fixation. All surgeries were performed by the same surgeon. Bone union, duration of distraction osteogenesis in days, time to consolidation in months, external fixation index (EFI), complications, and additional surgical interventions were recorded postoperatively. The modified Application of Methods of Illizarov (ASAMI) criteria were used to evaluate the operative effectiveness. Forty-one patients were enrolled in this study for analysis. The length of the bone defect ranged from 6 to 17 cm. All patients eventually achieved healing, and no patient experienced recurrence of infection or newly developed infection. The average time needed for healing was 13 months. In terms of the incidence of complications, 3 cases axial deviations, 5 cases docking site nonunion, 23 cases pin-tract infection, 14 cases knee joint stiffness or their joint mobility declined, 2 cases osteogenesis insufficient in the distraction area,1 case refracture, and 2 cases loose external fixation pins. In terms of the evaluations of fracture healing and function, 30 patients excellent, 6 patients good, 5 patients fair, and 0 patient poor. In terms of postoperative function evaluations, 21 patients excellent, 9 patients good, 7 patients fair, and 4 patients poor. For patients with femoral nonunion with large segmental bone defects, the monolateral external fixation can provide effective stability, improve compliance, and reduce complications.

Patients with diabetic osteoporosis (DOP) often suffer from poor osseointegration of artificial implants, which is a challenge that affects implant outcomes. The osteogenic differentiation ability of human jaw bone marrow mesenchymal stem cells (JBMMSCs) is the key to implant osseointegration. Studies have shown that the microenvironment of hyperglycemia affects the osteogenic differentiation of mesenchymal stem cells (MSC), but the mechanism is still unclear. Therefore, the aim of this study was to isolate and culture JBMMSCs from surgically derived bone fragments from DOP patients and control patients to investigate the differences in their osteogenic differentiation ability and to elucidate its mechanisms. The results showed that the osteogenic ability of hJBMMSCs was significantly decreased in the DOP environment. Mechanism study showed that the expression of senescence marker gene P53 was significantly increased in DOP hJBMMSCs compared to control hJBMMSCs according to RNA-sequencing result. Further, DOP hJBMMSCs were found to display significant senescence using β-galactosidase staining, mitochondrial membrane potential and ROS assay, qRT-PCR and WB analysis. Overexpression of P53 in hJBMMSCs, knockdown of P53 in DOP hJBMMSCs, and knockdown followed by overexpression of P53 significantly affected the osteogenic differentiation ability of hJBMMSCs. These results suggest that MSC senescence is an important reason for decreasing osteogenic capacity in DOP patients. P53 is a key target in regulating hJBMMSCs aging, and knocking down P53 can effectively restore the osteogenic differentiation ability of DOP hJBMMSCs and promote osteosynthesis in DOP dental implants. It provided a new idea to elucidate the pathogenesis and treatment of diabetic bone metabolic diseases.

Purpose: The increasing worldwide prevalence of anterior column-posterior hemi-transverse fracture (ACPHTF) brings formidable challenges to orthopaedic surgeons. Our newly-designed locking plate had previously demonstrated promising effects in ACPHTF, but evidence of their direct comparison with conventional internal fixations remains lacking. In this study, we aimed to compare our novel plate with the traditional devices via finite element analysis. Methods: The ACPHTF model was created based on a 48-year-old volunteer’s CT data, and then fixed in three different internal fixations: an anterior column locking plate with posterior column screws, double column locking plates, and our novel anatomical locking plate. These models were next loaded with a downward vertical force of 200 N, 400 N and 600 N, and the stress peaks and displacements of three different sites were recorded and analyzed. Results: We first tested the rigidity and found that our newly-designed locking plate as well as its matched screws had a greater stiffness especially when they were under a higher loading force of 600 N. Then we evaluated the displacements of fracture ends after applying these fixations. Both our novel plate and DLP showed significantly smaller displacement than LPPCS at the anterior column fracture line and the pubic branch fracture line, while our novel plate was not obviously inferior to DLP in terms of the displacement. Conclusion: This novel plate demonstrates a distinct superiority in the stiffness over LPPCS and DLP and comparable displacements to DLP in ACPHTF, which suggests this novel anatomical locking guide plate should be taken into consideration in ACPHTF.

The treatment of complex acetabular fractures remains a complicated clinical challenge. Our self-designed novel anatomical locking guide plate (NALGP) has previously shown promising potential in T-shaped acetabular fractures (TAF), but a direct comparison with conventional fixations is yet to be made. The TAF model was established based on a volunteer’s computer tomography data and then fixed with double column locking plates (DLP), a posterior column locking plate with anterior column screws (LPACS), and our NALGP. Forces of 200 N, 400 N, and 600 N were then loaded on the model vertically downward, respectively. The stress distribution and peaks and maximum displacements at three sites were assessed. We found that the stress area of all three plates was mainly concentrated around the fracture line, while only the matching screws of the NALGP showed no obvious stress concentration points. In addition, the NALGP and DLP showed significantly less fracture fragment displacement than the LPACS at the three main fracture sites. The NALGP was found to have less displacement than DLP at the posterior column and ischiopubic branch sites, especially under the higher loading forces of 400 N and 600 N. The fixation stability of the NALGP for TAF was similar to that of DLP but better than that of LPACS. Moreover, the NALGP and its matching screws have a more reasonable stress distribution under different loads of force and the same strength as the LPACS.

Background: Targeted gene delivery to the dorsal root ganglion (DRG) has been developed as a valuable approach for pain research. Nevertheless, conventional DRG microinjection approaches suffer from notable drawbacks: vertebral bone resection and facet joint destruction induce spinal instability, extensive tissue adhesion impedes repeated surgery, and multi-segment targeting remains challenging. Methods: To establish a multi-segmental DRG injection workflow, we developed a vertebral counting scheme based on mouse anatomical dissection. To guide our selection of target segments for viral delivery, Thy1-YFP-H transgenic mice was used to trace segmental DRG innervation patterns with good resolution. Anatomical dissection was then performed to examine the precise spatial relationship between each target DRG and its neighboring facet joints. With this anatomical roadmap, together with a custom designed temporary spinal stabilizer, we established a standardized injection procedure applicable to user-specified levels. Post-operatively, animal behavior was serially assessed, and finally in vivo GCaMP calcium imaging was conducted to verify functional viral transduction. Results: Vertebral counting based on the V-shaped white lines on the spinous processes enabled reliable identification of lumbar segmentation. YFP tracing clarified distinct segmental innervation patterns: L1-L2 fibers do not contribute to the sciatic nerve; L3-L5 collectively form the sciatic nerve; L6 fibers, plus minor L5 branches, constitute the pudendal nerve. Additional anatomical dissection confirmed that drilling at the base of the inferior articular process of the cranial vertebra provided a direct access route to the L3-L6 DRGs. Serial behavioral monitoring post-injection revealed transient functional disturbances, most of which resolved by postoperative day 21. Finally, concurrent jGCaMP8s imaging confirmed successful functional transduction: air-puff stimulation elicited robust calcium responses in transduced DRG neurons, whereas no such signals were detected in wild-type controls. Conclusion: We have established a reproducible viral delivery method that minimizes bone resection and avoids gross facet joint destruction through laminar drilling, while enabling multi-segmental injection into mouse L3-L6 DRGs. The combination of longitudinal behavioral monitoring and stimulus-evoked calcium imaging supported the surgical feasibility and functional transduction of this approach. This method thus provides an experimental toolkit that should be useful for dissecting somatic-visceral pain crosstalk through multi-segmental DRG genetic manipulation.