【Abstract】 Objective To investigate the feasibility of transpositional anastomosis of C4 anterior trunk and accessory nerve for functional reconstruction of the trapezius muscle so as to provide theoretical basis of repairing accessory nerve defects. Methods Thirty-six adult male Sprague-Dawley rats (weighing 200-250 g) were randomly divided into the experimental group (n=18) and control group (n=18). The transpositional anastomosis of C4 anterior trunk and accessory nerve was performed in the left sides of experimental group; the accessory nerve was transected in the left sides of control group; and the right sides of both groups were not treated as within-subject controls. The electrophysiological and histological changes of the trapezius muscle were measured. The values of the latencies and amplitudes of compound muscle action potential (CMAP) were recorded in the experimental group at 1, 2, and 3 months; the latency delaying rate, amplitude recovery rate, and restoration rate of muscular tension were caculated. The counts of myelinated nerve fibers from distal to the anastomotic site were analyzed. The transverse area of the trapezius muscle was also measured and analyzed in 2 groups. Meanwhile, the muscles and nerves were harvested for transmission electron microscope observation in the experimental group at 1 and 3 months. Results As time passed by, the experimental group showed increased amplitudes of CMAP, shortened latencies of CMAP, and improved muscular tension. At 3 months, the amplitude recovery rates were 63.61% ± 9.29% in upper trapezius muscle and 73.13% ± 11.85% in lower trapezius muscle; the latency delaying rates were 130.45% ± 37.27% and 112.62% ± 19.57%, respectively; and the restoration rate of muscular tension were 77.27% ± 13.64% and 82.47% ± 22.94%, respectively. The passing rate of myelinated nerve fibers was 82.55% ± 5.00%. With the recovery of innervation, the transverse area of the trapezius muscle increased, showing significant differences between experimental group and control group at different time points (P lt; 0.05). The transmission electron microscope showed that the myotome arranged in disorder at 1 month and tended to order at 3 months. Conclusion Transpositional anastomosis of C4 anterior trunk and the accessory nerve can effectively reconstruct the function of the trapezius muscle of rats.
Objective To evaluate the effectiveness of posterior malleolus fixation on the function of ankle in patients with ankle fracture. Methods Between June 2007 and June 2009, 110 patients with ankle fracture were treated with posteriormalleolus fixation in 59 patients (fixation group) or without fixation in 51 patients (non-fixation group). In fixation group, there were 31 males and 28 females with an average age of 62.6 years (range, 19-75 years); the causes of injury included traffic accident (20 cases), falling (18 cases), and sprain (21 cases) with a disease duration of 1-3 days (2.2 days on average); and the locations were left ankle in 32 cases and right ankle in 27 cases, including 6 cases of type I, 23 of type II, 19 of type III, and 11 of type IV according to the ankle fracture clssification. In non-fixation group, there were 38 males and 13 females with an average age of 64.5 years (range, 16-70 years); the causes of injury included traffic accident (15 cases), falling (12 cases), and sprain (24 cases) with a disease duration of 1-3 days (2.5 days on average); and the locations were left ankle in 22 cases and right ankle in 29 cases, including 8 cases of type I, 16 of type II, 19 of type III, and 8 of type IV according to the ankle fracture clssification. There was no significant difference in general data between 2 groups (P gt; 0.05). Results All patients of 2 groups achieved wound heal ing by first intention. The patients were followed up 12-18 months (16 months on average). X-ray films showed that fractures healed at 8-12 weeks (10 weeks on average) in fixation group and at 10-14 weeks (12 weeks on average) in non-fixation group. There were significant differences in the cl inical score (89.28 ± 8.62 vs. 86.88 ± 9.47, P lt; 0.05), postoperative reposition score (33.34 ± 2.15 vs. 31.24 ± 2.89, P lt; 0.05), and osteoarthritis score (13.22 ± 1.66 vs. 12.46 ± 2.03, P lt; 0.05) according to Phill i ps ankle scoring system between 2 groups at last follow-up. There was no significant difference in cl inical score of type I and II patients between 2 groups (P gt; 0.05), but significant differences were found in cl inical score and osteoarthritis score of type III and IV patients between 2 groups (P lt; 0.05). There were significant differences in the postoperative reposition score between 2 groups in all types of fractures (P lt; 0.05). Conclusion The posterior malleolus fixation may provide satisfactory cl inical functional outcomes for ankle fracture. Proper fracture classification and correct method of internal fixation are important for achieving good reduction and improving the long-term results.
Sports-related traumatic brain injury (srTBI) is a traumatic brain injury (TBI) caused by sports, which can result in cognitive and motor dysfunction. Currently, research on the molecular mechanism of srTBI and related drug development mainly relies on monolayer culture models and animal models. However, many differences exist in cell populations and inflammatory responses between these models and human pathophysiological processes. Most of the researches derived from the models can’t effectively conducted translational research. Emerging three-dimensional (3D) in vitro models bridge the limitations of traditional models in simulating the pathophysiological processes of human srTBI and provide new means to understand srTBI. A literature has reported the research progress of emerging 3D in vitro models in neurological diseases, but there is a lack of systematic summary of the mentioned models in srTBI studies. Here, we review the research progress of emerging 3D in vitro models of srTBI, discuss the advantages and limitations of existing models, and further prospect the future trend of srTBI models. This paper aims to provide a new research perspective for researchers in tissue engineering and sports medicine to study the molecular mechanisms of srTBI and develop neuroprotective drugs.