Anterior supra-acetabular external fixation for tile C1 pelvic fractures: a digital anatomical study and a finite element analysis.

OBJECTIVE: Investigating the anatomical characteristics of supra-acetabular screw corridor as well as comparing the biomechanical stability between semi- and full-length screw external fixations for Tile C1 pelvic fractures. METHODS: 50 male and 50 female uninjured pelvic CT data were converted into three-dimensional models and the supra-acetabular corridors were reconstructed by the Mimics software. The horizontal slice was redefined passing through the bilateral anterior inferior iliac spine and bilateral posterior superior iliac spine at the same time. On every horizontal slices, a 5 mm diameter virtual screw was placed along with the unilateral anterior narrowing to posterior narrowing of the supra-acetabular corridor, and the relevant parameters of the semi- and full-length screw fixations were measured from inferior to superior at an interval height of 2.5 mm until the width of the corridor was less than 5 mm. Thus, the insertion position was located, as well as the inclination angle ranges were measured. The same procedure was done on a bilateral supra-acetabular corridor for each patient. Last, a Tile C1 pelvic finite element model was simulated and fixed with either semi- or a full-length anterior supra-acetabular external fixator. A 500 N loading was tested on the model with three directions (cranial-caudal, anterior-posterior and lateral-medial) and the stiffness was determined by the max displacements. RESULTS: The insertion points of supra-acetabular screw for 66% (66/100) of men and 78% (78/100) of women were located at the outer lower part of the anterior inferior iliac spine (AIIS) (p < 0.001). The medial inclination angles of the screw were 29.50 ± 4.05° for men and 28.00 ± 3.78° for women (p = 0.007). The cranial inclination angles of the screw were 29.40 ± 5.38° for men and 28.57 ± 6.01° for women (p = 0.306). The safe inclination angle ranges of the semi-length screw were 3°-6° bigger than the full-length screw. For semi-length corridor, the widths were 14.07 ± 2.39 mm for men and 11.29 ± 1.81 mm for women (p < 0.001) and the depths were 71.77 ± 5.96 mm for men and 69.26 ± 5.21 mm for women (p < 0.001). For full-length corridor, the widths were 10.61 ± 2.10 mm for men and 8.44 ± 2.03 mm for women (p < 0.001) and the depths were 133.37 ± 7.60 mm for men and 129.01 ± 8.12 mm for women (p < 0.001). In the finite element analysis, the max displacements of the pelvis under three loading modes (cranial-caudal, anterior-posterior and lateral-medial) for semi-length fixation were 0.772 mm, 0.409 mm and 0.331 mm and for full-length fixation were 0.727 mm, 0.385 mm and 0.262 mm. CONCLUSION: The outer lower part of AIIS is recommended as an insertion point of the supra-acetabular screw with about 30° medial and cranial inclination angles, and the semi-length screw is safer for placing and has satisfactory biomechanical stability by compared with a full-length screw.

Reflection on improving the quality of the standardized training of resident in orthopaedics rotary training / 中华医学教育探索杂志

We carry out the tutorial system in the standardized training of residents,promote students to grasp the clinical skills and clinical research and thinking,and promote teachers' professional theoretical level and teaching ability.In the orthopedic rotation we define the teaching focus to the trainees of different seniority:for junior trainees,the training of medical records writing and basic clinical skills should be focused,and for senior trainees,the emphasis of training is to improve their clinical capacity of diagnosis and treatment.In teaching,the teaching methods of a combination of Multidisciplinary team (MDT) of bone and soft tissue tumors and problem based learning (PBL) have been actively tried to improve students' learning enthusiasm and initiative,which helps the trainees fully grasp the diagnosis and treatment of certain diseases.

Indications for screw fixation of posterior malleolas fractures / 中国组织工程研究

BACKGROUND:Posterior maleolar fractures are often accompanied by ankle joint instability,if the stability of ankle joint is not recovered,it is prone to traumatic arthritis of the ankle.However,the indications of internal fixation of posterior maleolar fractures remain controversial.OBJECTIVE:To explore the indications for internal fixation of posterior maleolar fractures by comparing the clinical effects of posterior maleolar fractures treated with internal fixation or not.METHODS:42 patients with maleolar fractures involving posterior ankle were recruited from the First Affiliated Hospital of Chongqing Medical University from January 2007 to January 2012.According to preoperative CT scans of ankle joint,42 cases were divided into the internal fixation group and the non-fixation group.27 cases in the fixation group had posterior maleolar fractures in more than 10％of the distal tibial articular surface and/or dislocation of the posterior maleolar fractures greater than 2 mm,and were treated with screws.15 cases in the non-fixation group had posterior maleolar fractures in less than 10％of the distal tibial articular surface anddislocation of the posterior maleolar fractures less than 2 mm,and were treated with non-operation.The average healing time of posterior maleolar fractures,postoperative complications,ankle-hindfoot scores of American Orthopedic Foot and Ankle Society were compared during the folow-up postoperatively.RESULTS AND CONCLUSION:Al of 42 patients with ankle fractures achieved bony union within 6 months.In the fixation group,1 case had postoperative superficial infection of the wounds in the medial ankle and lateral ankle,and the wound got healed completely with anti-infection therapy.One case in each group had postoperative superficial necrosis in the incisional edges,and got healed by dress changing.For the other cases,there was no wound infection,internal fixation loosening,breakage or failure and other adverse events during the folow-ups.Ankle functions were evaluated one year after operations according to the ankle-hindfoot score standard of American Orthopedic Foot and Ankle Society.The score of the fixation group was (83.74±10.35) points,with excelent ankle functions in 10 cases,good in 12 cases,fair in 5 cases,and no poor case,and the rate of patients achieving excelent and good ankle functions reached 82％; the score of non-fixation group was (85.60±10.40) points,with excelent ankle functions in 7 cases,good in 5 cases,fair in 3 cases and no poor case.The rate of patients achieving excelent and good ankle functions reached 80％.The ankle function evaluation results of both groups showed no statistical difference (P＞0.05).It is reasonable to consider posterior maleolar fractures is higher than 10％of the distal tibial articular surface and/or dislocation of the posterior maleolar fractures greater than 2 mm as the indications for internal fixation of posterior maleolar fractures.

QWIX screw fixation in repair of patellar fractures:continuous dynamic and static pressure in the broken ends of the bones / 中国组织工程研究

BACKGROUND:The most important influence caused by patel ar fracture is the breakage of knee extension apparatus continuity and potential uncoordination of patel ofemoral joint. The aim of patel ar fracture surgery is to restore the smoothness of patel ar articular surface and to maintain the continuity of knee extension apparatus, to provide stable effective fixation, so as to do early functional exercises. OBJECTIVE:To evaluate the clinical effectiveness of a fixation technique for patel ar fractures using QWIX combined with Kirschner wire and wire. METHODS:From September 2011 to September 2012, 30 patients with patel ar fractures were treated using QWIX screws combined with Kirschner wire and wire in the First Affiliated Hospital of Chongqing Medical University, China. There were 17 males and 13 females, at the age of 47.7 years on average. In accordance with the situation of comminuted fracture and the degree of displacement, QWIX screws or QWIX screws+tension band wire or QWIX screws+Kirschner wire+tension band wire were used for fixation. Active and passive knee motion exercises began at 1 day after surgery, without any external fixation. At 6 weeks, 3, 6, 12 months, and 1 year after surgery, the patients were fol owed up in out-patient clinic to identify fracture healing and to make sure whether complications appeared or not. The range of flexion and extension of bilateral knee was measured. The knee function of the affected side was evaluated using Bostman score at 1 year postoperatively. RESULTS AND CONCLUSION:Al patients were fol owed up for 12 to 24 months. 24 cases were healed within 3 months after surgery, and 6 cases were healed within 4 months after surgery, with an average healing time of 3.2 months. With time prolonged, the range of flexion and extension of bilateral knee gradual y increased. The knee function of patients recovered to the level before injury at 1 year after surgery. During fol ow-up, one patient experienced knee pain due to Kirschner wire loosening. No infection, knee pain, fixation failure, or flexion dysfunction occurred in the remaining patients. In accordance with Bostman score, there were excellent in 27 cases, good in 3 cases, and poor in 0 case, with an excellent and good rate of 100%at 1 year fol owing surgery. Results data suggested that QWIX screws combined with Kirschner wire and wire fixation in repair of patel ar fracture have some advantages such as continuous dynamic and static pressure at the broken ends of the bones, early flexion and extension exercises, and reducing the fixation-related complications. It is an effective method to repair patel ar fracture.

Twenty-year experience in the diagnosis and treatment of hepatic trauma / 国际外科学杂志

Objective To summarize the experience in the diagnosis and treatment of hepatic trauma. Methods The clinical data of 260 patients with hepatic trauma admitted from January 1988 to December 2007 were retrospectively reviewed with regard to degree of trauma, treatment methods, therapeutical effects, complications and SO on. Results One hundred and fifty-three eases were treated by operative management,1 07 cases by nonoperative management.236 cases were cured,24 cases died,and the case fatality rate was 10.2%.There were no death among 139 patients with hepatic trauma grades Ⅰ～Ⅱ,22 death among 119 grades Ⅲ～Ⅴ patients, all death of 2 in grade VI, which demonstrated the correlation between death and hepatic trauma grade was statistically significant. Complications appeared in 82 eases, mainly including Secondary hemorrhage, abdominal infection and so on. Conclusions Nonoperative management is suitable for hepatic trauma with stable hemodynamics. Operative management is rapidly selected when the hemodynamics aren't stable. The cooperation of many specialities can enlarge the application of nonoperative management and decrease complications.

Effects of GDNF gene-activated matrix on neuron protection after sciatic nerve injury in rats / 重庆医科大学学报

Objective:To evaluate the effects of glial cell line-derived neurotrophic factor(GDNF) gene-activated matrix(GAM) in protection of neurons after sciatic nerve injury.Methods:The peripheral nerve extracellular matrix was harvested by chemical extraction.GDNF GAM was comprised of the extracellular matrix and plasmids encoding GDNF.Sixty adult Wistar rats were randomly divided into three groups:group A(GDNF GAM conduits,n=20),group B(ECM conduits,n=20),group C(autografts,n=20).Lumbar enlargement was processed for Nissl staining,immunohistochemistry and RT-PCR for GDNF or iNOS and fluorescence observation.Fluorescence observation was used to confirm the expressing of GDNF in the spinal cord.Motoneurons(MN) of lesioned(L) and normal(N) sides were counted,and MN survival ratio(MSR=L/N) was calculated.Results:GDNF DNA can be retained in GAM,promoting transgene expressing in axotomized neurons in spinal cord for 12 weeks.In GAM group,the expression of GDNF mRNA was maintained for 12 weeks while the number of iNOS positive cells was decreased in comparison with ECM group.GAM grafts obviously increased the survival rate of motor neurons than that of ECM grafts(78.04%?3.50% vs 56.09%?1.89%) at 12 weeks postaxotomy.Conclusion:These results suggest that(1) GDNF GAM increases the GDNF mRNA and the amount of Nissl positive cells in the lumber enlargement;(2) GDNF GAM protects MN through a mechanism in relation to iNOS.

Effects of glial cell line-derived neurotrophic factor gene-activated matrix on repair of sciatic nerve defect of rats / 第三军医大学学报

Objective To evaluate the effects of glial cell line-derived neurotrophic factor(GDNF) gene-activated matrix(GAM) in bridging rat sciatic nerve defect.Methods The peripheral nerve extracellular matrix was harvested by chemical extraction.GDNF gene-activated matrix was comprised of the extracellular matrix and plasmids encoding GDNF.Ninety adult Wistar rats were randomly divided into three groups: group A(GDNF GAM conduits),group B(extracellular matrix conduits),group C (autografts).At the end of 12 weeks,rats from each group were subjected to walking tract analysis,electrophysiological and histomorphological studies.Results GDNF DNA could be retained in GAM,promoting transgene expression in the sciatic nerve,in GAM,and more importantly,in axotomized neurons in spinal cord for 12 weeks.The number of regenerated axons for the GAM grafts in the distal sciatic nerve was lower than that for autografts(2 117?294 vs 2 474?297) at 12 weeks.The sciatic nerve function index for the GAM grafts was lower than that for autografts [(30.92?2.98)% vs(26.27?2.71) %] at 12 weeks.Conclusion GDNF GAM may be a promising alternative to autografts for repair of rat sciatic nerve.

Hip and pelvic fractures and sciatic nerve injury / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the influence of hip and pelvic fracture, especially acetabular fracture complicated by sciatic nerve injury on clinical features and prognosis of sciatic nerve injury.</p><p><b>METHODS</b>From January 1987 to January 2000, 17 patients (14 male and 3 female) who had hip and pelvic fractures complicated by sciatic nerve injury were treated with operative reduction and internal fixation and followed up from 10 months to 5 years. The average age was 38 years (ranging 23-56 years). The left extremities were involved in 11 patients and the right in 6. Twelve patients underwent primary exploration and neurolysis and 5 patients underwent secondary operation.</p><p><b>RESULTS</b>Preoperatively, 8 patients were treated with large doses of oral narcotics to control their severe sciatic pain. Three of the 8 patients underwent patient-controlled analgesia and epidural analgesia. After operation, excellent and good rates of reduction and functional recovery of sciatic nerve were 94.1% and 88% respectively. Four patients still had sciatic pain and 2 patients failed to recover. Sciatic nerve function improved within 3-6 months after surgery in 11 patients.</p><p><b>CONCLUSIONS</b>Hip and pelvic fractures can result in sciatic nerve injury, especially common peroneal nerve injury and prognosis is poor. Open reduction and internal fixation combined with nerve exploration and neurolysis should be used as early as possible for severe sciatic pain.</p>

Curative effects of patellar fractures treated by open reduction and internal fixation with Cable Pin or tension band wire / 第三军医大学学报

Objective To explore the curative effects of open reduction and internal fixation with Cable Pin or tension band wire for patellar transverse fractures.Methods Totally 28 cases and another 30 cases were enrolled in the Cable Pin group(8 months for average follow-up time) and the tension band wire group respectively(16 months for average follow-up time).The operative time,the average clinical healing time and the average range of the knee flexion between the 2 groups were compared.Results Obvious superiority was observed in the Cable Pin group over the tension band wire group concerning the average clinical healing time and the average range of the knee flexion 6 months postoperatively (P

Surgical treatment of vascular injury / 中国普通外科杂志

Objective To study the management of vascular injury.Methods Retrospective analysis was made on the clinical data of 59 cases of vascular injury,including 55 cases of vascular injury in neck and(extremity) and 4 cases of portal vein and vena cava injury.Among them,21 cases had femoral artery injury with infection and 4 cases had vascular injury due to intervention therapy.All patients with vascular wound of extremity or neck had undergone hemostasis by compression and antishock treament before hospital admission.All cases of femoral artery injury with infection underwent hemostasis by arterial ligation and incision and(drainage) of abscess.Vascular anastomosis was performed in 11 cases,vascular grafting in 12 cases,and(vascular) repair in 14 cases.Results There were 2 deaths.5 cases had amputation(including a case of(femoral) embolism due to intervention trerapy).Postoperative intermittent claudication,decreased skin(temperature) and other signs of ischemia occurred in 21 cases of femoral artery injury with infection,but none developed limb gangrene. The other cases were discharged in good health.Conclusions In the treatment of vascular injury,wound hemostasis and antishock treatment should be done first to save the patient′s life and the management of the vascular injury depends on the situation,with the aim to try by all means to save the extremity.Vascular reconstruction is the main method for treatment of vassular injury.Vascular ligation can be done in cases of femoral artery injury with infection.

Surgical treatment of acute deep vein thrombosis of lower extremity / 中国普通外科杂志

Objective To evaluate the effects of surgical treatment of acute deep vein thrombosis (DV T) of lower extremity. Methods Thirty-six patients with a cute DVT of lower extremity were treated by thrombectomy with thrombolytic,a nticoagulant and compression on the affected lower extremity during and after op eration. Results No death and serious complications happened i n this series. Thirty-one patients were followed-up for 2 to 20 months with a n average of 9 months. Symptoms disappeared totally in 23 patients , 8 patien ts had slight edema in the lower extremities. Conclusions Com bination of thrombectomy the thrombolytic and anticoagulant agent,and comp ression of the affected lower extremity is a safe and effective method in the t reatment of acute DVT of lower extremity.