RESUMO
BACKGROUND: Coronal shear fractures of the distal humerus are not only rare and prone to misdiagnosis, but their surgical treatment can be challenging. We aimed to investigate the feasibility of exposing distal humeral coronal shear fractures with a combined lateral approach that preserves the extensors and lateral ulnar collateral ligament (LUCL) and to analyze the clinical efficacy of open reduction and internal fixation (ORIF) in the treatment of these injuries. METHODS: We included 45 patients who sustained coronal shear fractures of the distal humerus with the lateral epicondyle intact and were treated with ORIF from January 2013 to August 2020. The fractures were exposed by the lateral combined approach in which the tendons involving the common extensor, the extensor carpi ulnaris (ECU), and the LUCL were preserved. Two observation windows were formed anterior to and posterior to these tendons and the LUCL was used to achieve fracture reduction. Countersunk screws, with or without a plate placed on the posterior lateral condyle, were used to fix the fragments. The functional outcomes of these patients were reviewed and assessed with physical and radiographic examinations, range of motion (ROM) measurements, and self-evaluation Mayo Elbow Performance Index (MEPI) and Disabilities of the Arm, Shoulder, and Hand (DASH) scores. RESULTS: In total, 40 patients were followed up with for over 1 year and were included in the final analysis. The mean follow-up duration was 42±30 months (range, 12-107 months). The patients' mean age was 42 years (range, 14-74 years). According to the Dubberley Classification, there were 15 type I, 17 type II, and 8 type III fractures. At the final follow-up, the mean flexion-extension arc was 131° (range, 65-150) and mean pronation and supination was 73° (range, 45-80) and 71° (range, 40-80), respectively. The mean MEPI score was 88 (range, 61-97) points; the results were excellent in 21, good in 13, fair in 4, and poor in 2 patients. The mean DASH score was 11 (range, 0-42) points. Neither functional score nor range of movement was associated with age, sex, fracture type, injury type, or surgical timing. CONCLUSION: Reduction and stable fixation with internal fixation for coronal shear fractures of the distal humerus can be achieved by the lateral combined approach. Early functional mobilization allows for satisfactory restoration of elbow function.
RESUMO
OBJECTIVE: Depression is a common mental illness. Neural stem cell-derived extracellular vesicles (NSC-EVs) are involved in repairing neuronal injury. We estimated the mechanism of miR-16-5p in depression rats. METHODS: EVs were extracted from NSCs. The depression rat model was established by corticosterone (CORT) induction and treated with NSC-EVs. The depression behavioral/pathological changes in rats were assessed using forced swimming test, open field test, sucrose consumption test and western blotting. The neuronal apoptosis in hippocampal tissue were detected. CORT-induced PC12 cell model was established. EV uptake by PC12 cells was measured and PC12 cell apoptosis was detected. The downstream targets of miR-16-5p were predicted and verified. The expressions of miR-16-5p and MYB in rats, PC12 cells, and EVs were measured. Functional rescue experiments were conducted to verify the role of miR-16-5p and MYB in PC12 cell apoptosis. RESULTS: CORT induction increased neuronal apoptosis in hippocampal tissue and induced depression-like behaviors in rats, while NSC-EV treatment improved depression-like behaviors and apoptosis in rats. In PC12 cells, NSC-EVs decreased CORT-induced PC12 cell apoptosis. NSC-EVs carried miR-16-5p into PC12 cells. miR-16-5p knockdown in EVs partially reversed the inhibitory effects of NSC-EVs on CORT-induced PC12 cell apoptosis. miR-16-5p targeted to inhibit MYB to repress CORT-induced PC12 cell apoptosis. In vivo experiments further verified that NSC-EVs reduced neuronal injury in CORT-induced depression rats via the miR-16-5p/MYB axis. CONCLUSION: NSC-EVs-mediated alleviation on neuronal injury by carrying miR-16-5p to target MYB was highly likely one of the mechanisms by which NSC-EVs mediated miR-16-5p in neuroprotection of depression rats.
