A biomechanical comparison of cable tension band fixation for tibial avulsion fractures of the anterior cruciate ligament / 中华创伤骨科杂志

Objective To compare cable tension band fixation with other 3 fixations in terms of biomechanical stability for tibial avulsion fractures of the anterior cruciate ligament (ACL).Methods Eighty fresh porcine knees were randomized into 4 equal groups (n =20).For each knee,all the soft tissues were removed only to keep the femur-ACL-tibia complex.The knee complexes were used to create fracture models of standard Meyers-Mc Keever type Ⅲ at the ACL attachment region using a swing saw.The fracture fragments in the 4 groups were subjected to fixation respectively with intramedullary lag screws,high-strength suture,tension band wire and cable tension band.All the specimens were subsequently tested on a Material Testing Machine at a load rate of 60 mm/mm.The 4 groups were compared in terms of ultimate failure load,yield load,and fragmental displacement under single-cycle loading and multi-cyclic loadings.Results Cable tension band fixation displayed significantly higher ultimate failure,higher yield load and lower fragmental displacement than all the other 3 fixations (P ＜ 0.05).Conclusion As cable tension band fixation,which is convenient and economical,provides better biomechanical stability than other 3 fixations for tibial avulsion fractures of the ACL,it may allow earlier functional and weight-bearing exercise after operation.

Treatment of posterior dislocation and acetabular posterior column (wall) fracture with greater trochanteric os-teotomy via Kocher-Langenbeck approach / 局解手术学杂志

Objective To introduce the operation method and curative effect of posterior dislocation and acetabular posterior column ( wall) fracture with greater trochanteric osteotomy via Kocher-Langenbeck approach. Methods 14 cases of posterior dislocation and ace-tabular posterior column( wall) fracture who were treated by greater trochanteric osteotomy via Kocher-Langenbeck approach were collected, and the surgical methods, intraoperative situation and postoperative recovery were analyzed. Results The mean operating time is 105 min and the mean bleeding volum is 600 mL. After operation, there were 5 cases of anatomical reduction;8 cases of good reduction;1 cases of unsatisfactory reduction. Among the patients, 7 cases were of excellent clinical effect;4 cases were of good clinical effect, 3 cases were of medium clinical effect. Heterotopic ossification occurred in 3 cases and traumatic arthritis occurred in 4 case. Both acetabular posterior col-umn ( wall) and trochanter osteotomy ends were healed, and there was no iatrogenic sciatic nerve and femoral head necrosis injury. Conclu-sion In treatment of posterior dislocation and acetabular posterior column ( wall) fracture, greater trochanteric osteotomy via Kocher-Lange-nbeck approach can provide excellent exposure, and it is conducive to the reduction and fixation of fracture and dislocation.

Progress of study in auditory event-related potentials of novel events / 生物医学工程学杂志

This is a review of the progress in the study on auditory event-related potentials (ERP) of novel events. Several cognitive problems about the novelty ERP response on brain and the experiment methods are introduced. The mismatch negative potential (MMN) reflects the detection of deviant events, and MMN is related with the novelty P3. Familiarity and attention influence the novelty ERP response. Experiments results showed that the amplitude of ERPs in the frontal area was reduced with the enhancement of familiarity, while that in the parietal area had little change. Attention was helpful in increasing the amplitude of ERPs, and could make the corresponding brain area active. The functional significance of the response of ERP was discussed also.

Development of the study on emotion and electrophysiology / 生物医学工程学杂志

In this paper the state of emotion study using electroencephalogram is systemically introduced. The methods for emotion study including the analyses of EEG frequency spectrum, evoked potentials, event-related potentials and the non-linear dynamical analysis are summarized, and the latest development is reviewed. Lastly the effect of emotion on other brain functions, e.g. memory, is discussed. In the paper the developments of emotion studies are also predicted.

Influence of pedicle transverse diameter on security of screw implantation in adult thoracic vertebrae / 吉林大学学报(医学版)

Objective To identify the effect of morphology of adult upper and middle thoracic pedicle on security of screw implantation.Methods Five fresh adult cadaveric thoracic spine from T1 to T8 were harvested.Pedicle transverse diameters were measured and compared with the smallest diameter(4.5 mm) of screw used in clinic.The screws were inserted and implant effect was observed.Results The mean transverse diameter of adult thoracic(T1-T8) were T1:4.74(3.85-5.25)mm,T2:4.51(3.45-5.25)mm,T3:4.15(3.60-4.65)mm,T4:3.75(3.10-4.50)mm,T5:4.25(3.70-4.65)mm,T6: 4.53(4.40-4.70)mm,T7:5.38(5.25-5.60)mm,T8:5.55(5.50-5.80)mm.Of all specimens,there were 9 specmen(22.5%) whose tranverse diameters were smaller than 4.5 mm.After implantation,two screws broke through pedicle lateral wall.Conclusion Adult pedicle transverse diameters in T3-T4 are smallest,transpedicular screw placement is difficult in some of these vertebrae,but in most of thoracic vertebrae,pedicle tranverse diameter could permit screw implanting in security.

Investigation by comparison on the posttraumatic stress response among SARS patients, hospital staffs and the public exposed to SARS / 中华行为医学与脑科学杂志

Objective This paper focuses on the investigation of the occurrence and influential factors of post-traumatic stress disorder (PTSD)in SARS patients, hospital staffs and the public expo sed to SARS. Methodes Three groups were assessed by scale of self-compiled stressor Questionnaire, impact of event scale-revised (IES-R) , PSSS, SCSQ, SES and EPQ. Results 1. The incidence of PTSD symptoms in the three groups were 55.1% ,25.8 % and 31.18 %. 2. The main cause of the different incidence was the difference of the stressor intensity and characters. Negative coping was the risk factor of SARS patients and the public; Self-esteem was the protected factor of SARS patients and the hospital staffs; Social support was a protected factor on the hospital staffs. 3. Comparing to the first investigate in September,2003 ,the data of follow-up study in September,2004 showed that the prevalence items significant decreased. Conclusions 1. The investigation concludes that all three groups of people exposed o SARS exhibit PTSD symptom. SARS patients have the highest occurrence ( P ＜ 0.01 ). 2. The main influencing factors of different incidence of PTSD in different groups are intensities and characteristics of stressors. Different people who had PTSD symptoms have different influencing factors. 3. With the change of time , the PTSD symptoms significant relieve with the attenuation gradually of exposure degree of stressor.

Follow-up study on mental symptoms of SARS patients / 中华行为医学与脑科学杂志

Objective To investigate mental symptoms of SARS patients and its related factors for three period-admission, discharge and three months after SARS crisis and to carry out mental intervention and effect evaluation.Methods The mental problems of SARS patients in three periods of admission, discharger and three months after discharger were continuously investigated.114 SARS patients came from seven designated hospitals in Taiyuan of Shanxi. The participants were assessed by self- compiled stressor Questionnaire, PSSS, SCSQ, SES, SCL-90 and EPQ.Results 1.Change tendency of factor score: The SCL-90 total and factors scores including obsessive-compulsion, phobic anxiety went up during discharge compared with admission. After that,these factors scores went down. The factors scores of somatization and depression descended continuously for three period. 2.Change tendency of the incidence:The incidence on factors of obsessive-compulsive, interpersonal sensitivity, phobic anxiety ascended during discharge compared with admission. Then,these factors scores descended. The other factors went down continually for three periods.3. The self-esteem was influencing factor on mental symptoms of SARS patients for three periods.Conscientious condition severity was influencing factor in admission and discharge.Negative coping was influencing factor in discharge and three months after SARS crisis. Education was influencing factor in three months after SARS crisis.4.After intervention ,the most mental symptoms of 35 SARS patients had mental problems were improved. Dissimilarly, a part of mental symptoms got severity.Conclusions 1.SARS patients exist severe mood disorders and have different influencing factors for three periods. They should be evaluated continuously and be intervened in time.2.The effect of mental intervention by telephone is not uncertainty.

Development of the ultrasonic characterization of biological tissue elasticity / 生物医学工程学杂志

The variation of tissue elasticity or stiffness is related with diseases of tissue, so the characterization of tissue elasticity is important to diagnosis. There are four methods for ultrasonic characterization of tissue elasticity: imaging inspection techniques, vibration velocity measurements, quasi-static strain measurements and parametric methods. The theories of the method of vibration velocity measurements and the method of quasi-static strain measurements and their new developments are discussed in this paper. The applications and the problems of this technique are discussed also.