Objective To develop a tractive spinal cord injury model in rats with a novel spinal distractor so as to supply the rel iable animal model for researching the pathological mechanism and rehabil itation treatment of tractive spinal cordinjury. Methods A novel spinal distractor was prepared based on previous study. Sixty adult Sprague Dawley rats (weighing 250-300 g) were randomly divided into 5 groups, 12 rats in each group. T12-L3 spinal structures in the rear area were exposed and then T13-L2 spinal cords were revealed via dual laminectomy and kept integrity. In group A, a novel spinal distractor was placed without distraction; in groups B, C, D, and E, the T12-L3 spines were tracted with a novel spinal distractor which put on transverses process of T12-L3 vertebrae. During the tractive period, the somatosensory evoked potential (SEP) was used to monitor spinal cord function. The SEP ampl itudes descended 50% and kept distracting for 5 minutes in group B and for 10 minutes in group C, and descended 70% and kept distracting for 5 minutes in group D and for 10 minutes in group E, respectively to establ ish the tractive spinal cord injury model of T11-L2. The improved combine behavioral score (ICBS) was recorded at 1 and 7 days after injury in 6 rats of each group. The T13-L2 spinal tissue specimens were harvested for the morphological observation by HE and Nissl’s staining and for neurons counting. Results In group A, the ICBS score was 0 at 1 and 7 days after operation, showing significant difference when compared with the scores of the other groups (P lt; 0.05). The ICBS scores of groups D and E were significantly higher than those of groups B and C (P lt; 0.05). Edema and hemorrhage were observed in spinal cord surface and normal morphological structures were destroyed at different extent in groups B, C, D, and E at 1 day. There were adherence and congestion between spinal cord surface and peripheral issue without luster at 7 days, and dura depression was observed at the injury section, especially in group E. Necrosis and dissolution occurred in some neurons, and Nissl body structure dissolved or disappeared in groups B, C, D, and E. The neuron counting gradually decreased in accordance with the aggravation of injury in groups B, C, D, and E, showing significant difference when compared with group A (P lt; 0.05). Significant differences in neuron counting were found among groups B, C, D, and E (P lt; 0.05). Conclusion The tractive spinal cord injury model in rats can be successfully establ ished with novel spinal distractor, and the model establ ished by SEP ampl itude descending 70% and keeping distracting for 10 minutes is more suitable for study in tractive spinal cord injury.
Objective To investigate the operative method and to evaluate the cl inical outcome of proximal femoral nail antirotation (PFNA) in treating reverse obl ique fractures of intertrochanteric region of the femur. Methods From January 2007 to February 2008, 30 cases of reverse obl ique fractures of intertrochanteric region of the femur were treated by closed reduction and fixation with PFNA, including 14 males and 16 females and aging 40-88 years old with an average of 68.6years old. All patients had closed fractures. According to AO classification, there were 6 cases of 31-A3.1 type, 7 cases of 31-A3.2 type and 17 cases of 31-A3.3 types. The time from injury to operation was 2-14 days (with an average of 5.3 days). All 31-A3.1 and 31-A3.2 type farctures and 9 cases of AO 31-A3.3 type fractures were fixed with the standard PFNA, and 8 cases of 31-A3.3 type fractures with the PFNA-long. The cl inical and radiological examinations were done at 1, 2, 3, 6, 12, and 18 months after operation. The cl inical outcomes were evaluated according to the Sanders scoring. Results Iatrogenic fracture of femoral shaft occurred in 1 case; no additional procedures were appl ied as fracture kept favorable stabil ity. Superficial infection occurred in 1 case at 5 days after operation, wound healed after dressing change and intravenous antibiotic therapy. Other wounds healed by first intention. All cases were followed up for 12-19 months (mean 14.1 months). All fractures healed uneventfully after 12-30 weeks (mean 16.2 weeks). Five patients complained of hip pain, 2 patients had lateral leg pain, and the pain was el iminated after symptomatic treatment. One case compl icated by ipsilateral fracture of the tibial plateau had functional disturbance of knee, and one case compl icated by ipsilateral fracture of the acetabulum and pelvis had functional disturbance of hip, and the function was improved after functional exercise. No compl ications such as cut-out or breakage of the implants occurred. According to Sanders criteria, the cl inical results were excellent in 22 cases, good in 6 cases, and poor in 2 cases. The excellent and good rate was 93.3%. Conclusion PFNA is an effective treatment method for reverse obl ique fractures of intertrochanteric region of the femur, with a high rate of bone union, minor soft tissue damage, early functional exercise and acceptable compl icationrelated to implant.
Laparoscopic Roux-en-Y gastric bypass (LRYGB) was recommended as the gold standard procedure for metabolic and bariatric surgery by the National Institutes of Health in the 1990s and then had been adopted till now, which could effectively control excess weight and treat metabolic diseases relevant to obesity in a long term. The current LRYGB procedure had been performed more than half a century of development and update, and is still constantly evolving. Standardized and precise surgical procedures are of great significance in ensuring treatment effect and reducing the incidence of complications. Thus, the author reviewed the development process of LRYGB, further understanding and emphasizing the importance of standardized and precise surgical procedures.