Objective To discuss the timing and methods of operative treatment of acetabular fractures of AO Type C (double- column fractures). Methods From February, 1999 to January, 2004, we treated operatively 46 cases of AO Type C acetabular fractures, including 23 cases of C- 1 type, 14 cases of C- 2 type, and 9 cases of C- 3 type. 15 cases were treated through ilioinguinal approach, 10 cases through improved Kocher- Langenbeck approach, and 21 cases through combined anterior and posterior approaches. There were 3 groups of patients according to the time from injury to operation: 15 cases got operation within 1st week after injury (Group A); 23 cases within 2nd week (Group B); 8 cases within/after 3rd week (Group C). All of them were checked with radiography and 3D CT scan before and after operation. Results 34 cases( 73.9% ) obtained anatomical reduction, 8 cases( 17.4% ) got imperfect reduction, and 4 cases( 8.7% ) had unsatisfactory reduction. All the patients were followed up for 1 year to 4 years, averaging 31 months. According to D' Aubigne and Postel Hip Score, joint function was rated as excellent in 32 cases( 69.6% ) , good in 5 cases( 10.9% ) , fair in 5 cases ( 10.9% ) and poor in 4 cases ( 8.7% ) . As far as reduction was concerned, there was a significant difference (P0.05). As far as joint function was concerned, there was a significant amelioration in Groups A and B compared with Group C (P0.05) between group A and Group B. Conclusions Good knowledge of AO classification of acetabular fractures combined with particular radiological data can result in correct diagnosis of Type C acetabular fractures. Operations should be carried out within 2 weeks after injury and efforts should be made to ensure anatomical reduction. To achieve good clinical results in treatment of Type C acetabular fractures, suitable approaches and correct reduction and internal methods are essential

Objective To simulate the process of lag screw insertion on intact pelvises under guidance of conventional fluoroscopes or 2D and Iso-C3D computer-assisted navigations and evaluate the accuracy and practicability of the computer-assisted navigation. Methods Six dried intact adult pelvic specimens were selected and divided into three groups randomly. A total of 54 hollow screws were placed in bilateral pedicles of S1 and S2, anterior column of bilateral acetabulum, anterior column of bilateral acetabulum and pubic symphysis of intact adult dried pelvic specimens of three groups under guidance of conventional fluoroscopy, 2D and Iso-C3Dcomputer assisted navigations, respectively. The accuracy of the screw positions, the average operating time of each screw insertion and the average time of radiation exposure during the insertion of each screw were compared among three groups. Results There were significant differences in the accuracy of the screw positions, the average operating time and the average time of radiation exposure among three groups (P＜0.01). The navigation with Iso-C3D appeared to provide the highest accuracy and the shortest operating time of all guidance techniques. The mean operating time and the average time of radiation exposure of the conventional fluoroscope were the longest among three groups. The average time of radiation exposure of the 2D computer-assisted navigation was the shortest.Conclusions Iso-C3D computer-assisted navigation is the most accurate and expeditious means of all guidance techniques. The time of radiation exposure can be significantly reduced by both 2D and Iso-C3D computer-assisted navigations.

Objective To study the effect of conditioned media for rat bone marrow mesenchymal stem cells (BMSCs-CM) on palmitic acid (PA)-induced insulin resistance (IR) in HepG2 cells and its underlying molecular mechanisms.Methods HepG2 cells were treated with or without BMSCs-CM and L-DMEM in the presence or absence of PA.Glucose utilization in HepG2 cells were detected with PAS,glucose and glycogen measurements.Western blotting was used to assess the expression of phospho-insulin receptor substrate (p-IRS),phosphatidylinositol 3-kinase (PI3 K) and p-AKT.Results (1) Incubation of HepG2 cells with 0.25 mmol/L PA for 24 hours significantly increased the glucose concentration and decreased the glycogen content (P ＜ 0.05) in the media.(2) Treatment with BMSCs-CM significantly ameliorated the glucose and glycogen alteration in cells pretreated with PA (P ＜ 0.05),however,no obvious effect of BMSCs-CM on the cell glucose and glycogen production.(3) BMSCs-CM treatment also increased protein expression of p-IRS,PI3K and p-AKT in PA incubated HapG2 cells (P＜ 0.05).The effect of BMSCs-CM on PI3K and p-AKT expression could be mimicked upon addition of 740Y-P,a PI3K agonist,but abolished by LY294002,a PI3K specific inhibitor.Conclusions BMSCs-CM could improve the insulin sensitivity in HepG2 cells pretreated with PA through upregulation of insulin signaling component expression.

Objective To investigate the effects of reciprocal inhibition on motor function connectivity in the brains of stroke patients.Methods Thirty patients with stroke were randomly divided into a treatment group (n =15) and a control group (n =15).The control group underwent normal limb positioning,medium frequency electrotherapy,circulated compression of the limbs,etc.The treatment group received conventional rehabilitation treatment plus reciprocal inhibition treatment for 30 min daily,6 times a week for 4 weeks.All of the patients were assessed before and after treatment using the Canadian neurological scale (CNS),the Frenchay activities index (FAI),the motricity index (MI) and functional magnetic resonance imaging of the motor cortex in a resting state (rs-fMRI).Results In both groups the average CNS,FAI and MI scores improved significantly.Compared with the control group,the changes in FAI and MI scores in the treatment group improved significantly more.The coefficient of functional connectivity of the bilateral motor cortex decreased significantly after treatment in both groups.In the treatment group the motor cortex functional connectivity correlated significantly with the improvements in MI scores.Conclusions Reciprocal inhibition can accelerate the improvement of extremity motor function and ability in the activities of daily living significantly after stroke.It reduces functional connectivity in the bilateral motor cortex in ways significantly correlated with improvements in motor function.

BACKGROUND:Under physiological conditions, nerve roots can move along with the movement of limbs and spine. However, the mechanisms of nerve root stretch injury under physiological conditions and the neurological dysfunction after injury are unclear.
OBJECTIVE:To review the reason of nerve root stretch injury, and to analyze the mechanism of nerve function from biomechanics, pathology and neurophysiology.
METHODS:A computer-based online search of PubMed database was undertaken by the first author to identify the articles related to the research of nerve root injury and nerve stretch injury between 1990 and 2012, with the key words of“nerve root, nerve, stretch injury”. A total of 391 articles were screened out. The articles on the anatomy and biomechanics research of nerve root were included, as wel as the pathology and neurophysiology research after nerve root stretch injury. Final y, 44 articles were included for review.
RESULTS AND CONCLUSION:Nerve root can be stretched along with limbs and spine movement. However, diseases or trauma may cause pathological nerve root stretch, and thus leading neurological dysfunction. The nerve root is often influenced stretch because of its anatomical and tissue structure. Mechanical injury mechanism of stretch composes of peripheral (peripheral nerve conduction stress) and central mechanism (displacement of spinal cord content). Pathological studies found that the local fibrosis is caused by the extracted serum protein that difficult to remove after injury, and this is because of the shortage of lymphatic system in nerve roots. Fibrosis can cause nerve root ischemia, affect the nerve function, and change the biomechanical properties of nerve root. Nerve root injury can cause primary and secondary injury of internal axons, and this is the main reason for neurological dysfunction after injury.

Objective To explore the feasibility of Ilizarov technique in managing large tibia defects combined with soft tissue defects.Methods A total of 24 patients with large tibial defects combined with soft tissue defects caused by compound open tibial fractures were fixed with Ilizarov technique from September 2003 to September 2010.All patients belonged to open tibial fractures,including 20 patients with Gustilo type Ⅲ B and four with Gustilo type Ⅲ C.After debridement,the soft tissue defect areas was 10 cm ×6 cm and the bone defect was(8 ±4)cm.Fifteen patients with tibial defects ＜5 cm were treated with one stage debridement,fibula resection and tibial defect end compression.The other nine patients with tibial defect ＞ 5 cm were managed by one stage debridement,bone transport and bone lengthening.Then,15 patients were treated with one stage debridement,wound closure or wound reduction,bone grafting treatment and second stage cleansing of the incarcerated skin and fracture end.Results All patients were followed up for average 14 months(10-24 months),which showed reconstruction of the bone defects,restoration of the limb length,fracture healing and less than 2 cm difference between health limb and contralateral limb.One patient experienced common peroneal nerve palsy after operation,but recovered three months later.Of all,19 patients recovered without extra surgery,three restored with skin graft and two received skin flap.Conclusion Ilizarov technique is an effective option for treating the tibial defects combined with soft tissue defects at one stage.

Objective To explore the efficacy of temporary occlusion of abdominal aorta in the treatment of massive bleeding after pelvic fracture.Methods From May 2003 to May 2010,temporary occlusion of abdominal aorta was performed for 23 patients with massive bleeding after pelvic fracture.There are 15 male and 8 female patients with a mean age of 32 years (range,17-62 years).The mechanisms of injury included traffic accidents in 17 cases,falls in 4,engine injury in 1 and crash injury in 1 case.According to AO classification,4 cases were of type B2,4 of type B3,2 of type B3,1 of type C1,4 of type C2,and 12 of type C3.After aorta occlusion,the internal iliac vessel was ligated and the bleeding sites were tamponed.The fractures of pelvis were reduced.External fixation was used in 17 cases and screws and plates were used to fixation in 6 cases.Results All cases were rescued successfully.The average volume of blood transfusion was 4000 ml (range,1500-8500 ml).Intraoperative self-blood transfusion was performed in 14 patients.The average volume of self-blood transfusion was 1500 ml (range,700-5000 ml).Twenty-one patients were followed;the duration of follow-up was 26 months (range,5-36 months).The functional results were excellent in 11 cases,good in 4,fair in 3 and poor in 2 according to Majeed scores system.Complications included 2 cases of infection,1 of lower limb deep venous thrombosis,1 of malreduction of sacroiliac joint,and 1 of malunion of pelvic fracture.No complication was found due to the aorta occlusion or the internal iliac vessel ligation.Conclusion Temporary occlusion of abdominal aorta was an efficient and quick method in the treatment of massive bleeding after pelvic fracture.

BACKGROUND: Previous studies have demonstrated that LRP16 is an estrogen-responsive gene. Its expression level is strongly associated with the proliferation and invasive growth of human breast cancer cells.OBJECTIVE: To construct a LRP16 targeting vector and screen mouse embryonic stem cell clones with homolougous recombination of an inactive LRP16 gene.DESIGN: Constructing an inserting inactivation target by inserting SA-RIES-β geo expression cassette.SETTING: Bioregulatory Laboratory of the Third Medical Department of Kyushu University in Japan and Department of Molecular Biology, General Hospital of Chinese PLA.MATERIALS: The materials used here were mainly provided by the Bioregulatory Laboratory, the Third Medical Department of Kyushu University in Japan. The mouse genomic library in pBeloBAC11 Vector was purchased from lnvitrogen Corp. The competent TopF10 was purchased from Beijing Tiangen Biotech Corp. pcDNA3.1(+) vector was kept in our laboratory. Mouse ES cells were provided by Kyushu University.METHODS: The experiment was performed in Kyushu University and Department of Molecular Biology of PLA General Hospital from November 2004 to May 2005. Targeting sequence of LRP16 gene was obtained from 129 mouse genomic Bacterial Artificial Chromosomes library based on polymerase chain reaction (PCR) screening. The SA-RIES-β geo fragment was inserted within LRP16 fifth exon to inactivate LRP16. ES cells were screened with G418 and the homologously recombinant clone was identified by Southern blot analysis.MAIN OUTCOME MEASURES: Clones with homologous recombination.RESULTS: The LRP16 fragment including exon 5 to 11 was subcloned into the pBluescript SK Ⅱvector. Restriction map demonstrated that the SA-IRES-β geo fragment was correctly inserted into the LRP16 fifth exon. Southern blot results showed that there was an ES clone with targeting sequence homologously inserted.CONCLUSION: A LRP16 gene targeting vector is constructed and a homologous recombinant is obtained.

Objective To perform anatomic study on percutaneous cannulated-screw fixation of symphysis pubis diastasis in human cadaveric pelvic specimens so as to provide a basis for clinical practice of the technique.Methods Fifteen adult pelvic cadaveric specimens were dissected to expose pubic symphysis,peripheral major vascular nerve,spermatic cord and round ligament of the uterus.Thickness of pubic symphysis and distance between the outer edge of pubic tubercle and spermatic funicle or round ligament of uterus were measured respectively.Distances were measured respectively from entry and exit points to the above-mentioned structures in the direction of guide pin.Entry depth and angles of guide pin with the coronal plane and cross section of the human body were measured.Surgery was simulated to prove the surgery effect through post-surgery filming and CT.Results Thickness of symphysis pubis was gradually reduced from up to down.Pubic tubercle part was the most thick and it could accommodate a 7.3 mm cannulated-screw.Entry and exit points of cannulated-screw were in certain distances with the important nervusvascularis and spematicfunicle (or round ligament of uterus) in the periphery,which were invulnerable to damages in the process of surgery.Proper lengths of cannulated screws were (73.6 ± 1.3) mm for males and (72.4 ± 1.7)mm for females (t =3.146,P ＜ 0.05).Screw thread was completely embedded in pubic tubercle.Angles of guide pin with coronal plane and cross section of human body were (7.3 ± 1.1) °and (6.4 ± 1.0) ° for males (6.9 ± 1.5) ° and (6.1 ± 0.6) ° for females.Radiography and CT findings confirmed that all pin tracks were in the bone substances with angle and length of screws staying within the scope of experiment.Conclusion Percutaneous cannulated screw fixation is reliable and safe for symphysis pubis diastasis.

Objective To establish a reliable unstable pelvic fracture model with sacral plexus stretch injury in goats and to detect electrophysiological signals when pelvis is shifted in different orientations and distance.Methods Twenty-four goats were divided into three groups of 8 animals each:pelvic longitudinal displacement was induced in group A,pelvic lateral displacement in group B,and pelvic dorsal displacement in group C.Animal left L6 and S1 nerve root and initial segment of sciatic nerve were exposed to connect stimulating and receiving electrodes respectively.Left pelvis was shifted at the speed of 0.25 mm/s to produce the model of unstable pelvic fracture with sacral plexus stretch injury.Electrophysiological signals of L6 and S1 were recorded when the placement of pelvis was 0,0.5 and 1.0 cm respectively.Results With pelvic displacement,the threshold potential,maximum stimulus potential and incubation period were gradually increased,but the peak-to-peak value became smaller gradually.When the pelvis displaced 0.5 cm at different orientations,group A showed improved threshold potential and incubation period (P ＜0.05),decreased peak-to-peak value (P ＜0.05),and no significant change in maximum stimulus potential(P ＞0.05);group B only showed lowered peak-to-peak value with no significant variations in other electrophysiological signals (P ＜ 0.05);group C had no significant variations in all electrophysiological signals (P ＞ 0.05).When the pelvis displaced 1.0 cm at different orientations,groups A and B showed improved threshold potential,maximum stimulus potential and incubation period (P ＜ 0.05) and lowered peak to peak value (P ＜ 0.05);group C showed higher incubation period with no significant variations in other electrophysiological signals(P ＜0.05).Between groups,the amplitude of variation in electrophysiological signals was the most in group A and the least in group C.Conclusion After unstable pelvis fracture in goats,sacral plexus stretch injury is the most serious in longitudinal displacement of the pelvis.