For orthopaedic care of patients to continue to improve, new approaches, especially minimally invasive spinal technique, must be continually developed.To verify this technique actually provides improved outcomes, these approachs must be subjected to rigorous scientific study. However, because outcomes of clinical interventions only can be studied in human subjects, this practice must not only meet scientific criteria. it also must meet strict ethical criteria. The author analysised the state of minimally invasive spinal technique in china and foreign countries, and illustrated ethical problems and countermeasure on playing of minimally invasive technique into spinal practice.

Objective To explore a new method in the treatment of odontoid pr ocess fracture with a self-designed screw and anterior percutaneous odontoid fix ation. Methods Computerized tomography (CT) was used to measure the coronal and sagittal external diameter of the base of odontoid process, the length of the od ontoid process, the total height of the axis and the angle between the axial lin e of the odontoid process and the vertical line of the anterosuperior border of the C3 vertebral body in 40 normal adults aged from 20 to 45 years. Ten odontoid process fractures were fixed with cannulated anterior odontoid screws and monit ored under fluoroscope. According to Anderson's classfication, there were 4 of t ype Ⅱand 6 of type Ⅲ. 4 had no any displacement of the dens, 3 had displacemen t less than 5 mm, and 3 had displacement of 5 mm or more. The fractures were fre sh in 8, and the other 2 were old. Each fracture was fixed by one screw, and ant erior bone-graft was performed in old fracture after screw fixation. Results The coronal external diameter of the base of odontoid process was (8.8?1.2) mm, wh ile the sagittal external diameter was (10.9?1.0) mm, the length of the odontoi d process was (14.2?1.2) mm, the total height of the axis was (38.2?1.8) mm an d the angle between the axial line of the odontoid process and the vertical line of the anterosuperior border of the C3 vertebral body was 23.1??1.4?. Satis factory results were achieved in all patients, and all screws were in good posit ion. No neurological deterioration occurred. After a mean follow-up of 19 months (range, 10 to 25 months), 8 cases showed radiographic union, while 2 nonunion. Neither clinical symptoms nor screw loosening or breakage occurred. Conclusion The direct anterior percutaneous screw fixation is practical for fractures of t he dens with appropriate instrumentation, as long as the surgeon is familiar wit h the topographic anatomy and makes sure the insertion point, the depth and the angle on percutaneous insertion of the screws, the satisfactory outcome will be obtained. There is no stiffening of the C1,2 and the motion limitation. The ant erior percutaneous procedure is surgically less traumatic than the conventional cervical approaches. One screw is optimal for this procedure.

The author analysised the state of playing of human cadaver specimens in orthopedic biomechanical study in china and illustrated ethical problems an countermeasure on this issue.

ObjectiveTo study the effect of angiotensin Ⅱ type 1 receptor antagonist (ARB) losartan on reducing the incidence of stroke in patients which suffer from hypertension and atrial fibrillation(AF).MethodsProspective randomized analysis was used to divide one hundred and eighty hypertemion patients with atrial fibrillation into two groups.ARB treatment group was treated with losartan (n =90) and beta-blockers treatment group was treated with metoprolol ( n =90),all patients were treated for three years and followed up.Blood pressure,pulse pressure,incidence of stroke and myocardial infarction and mortality of cardiovascular events were evaluated.ResultsAfter antihypertensive treatment,blood pressure was reduced in two groups,the pulse pressure in losartan group was reduced obviously( all P ＜0.01 ).The incidence of stroke and myocardial infarction and mortality of cardiovascular events in losartan group were 22.2％,10.0％ and 13.3％,respectively,lower than that in metoprolol group 70.0％,40.0％ and 44.4％ ( all P ＜0.01 ).ConclusionLosartan reduced the incidence of stroke in the hypertension patients with AF.

Objective To study the feasibility and clinical effect of percutaneous C2 pedicle lag screw in treatment of Hangman's fracture and define the indications of the technique. Methods There were 9 patients including 5 males and 4 females at average age of 36 years (26-68 years). According to a Levine and Edwards System, there were 5 patients with type Ⅰ hangman' s fracture, 3 with type Ⅱ hangman' s fracture and 1 with type Ⅱ A hangman' s fracture. According to American spinal injury association (ASIA) system, the spinal cord function was ranked at Type D in 2 patients and Type E in 7. All patients achieved anatomic reduction by skull traction. Under general anesthesia, 9 patients were fixed with percutaneons C2 pedicle lag screw. The whole procedure was done under monitoring of "C"-arm fluoroscopy for safety and accuracy. Results All patients obtained bony fusion within 2-3 months, with no infection, neurological deficits, vertebra artery injury or other complications. CondusionsThe percutaneous C2 pedicle lag screw fixation is minimally invasive and effective for treatment of Hangman's fracture. During the course of treatment, the function of upper cervical spine remains unaffected.

Objective To explore different treatment choices for unilateral cervical facet locking. Methods The study involved 32 patients with cervical unilateral facet locking. Successful reduction by the skull traction was done in eight patients, of whom three were fixated by the head and neck chest plas-ter after a month of traction. Five patients were treated with anterior decompression and internal fusion fixation. The other 23 patients resulted in failure of traction and then were treated with anterior reduction, discectomy and internal fusion fixation in 14 patients, subtotal vertebral decompression and bone graft fix-ation in three, posterior open reduction and anterior bone graft fixation in one, posterior reduction, fixation and internal fusion fixation in three and posterior reduction and decompression plus anterior discectomy decompression and bone graft fixation in two. Due to misdiagnosis, one patient was treated with anterior decompression and fusion eight months after injury. Results A follow-up for average 18 months showed cervical instability in two patients who were treated with only traction, without fusion. The patients treated with anterior cervical fusion obtained bone union after 12 weeks, with satisfactory cervical physiological curvature and vertebral height. There were no internal fixation complications or neurological complications. Conclusions The treatment of lower cervical unilateral facet locking needs a compre-hensive considerations on whether there associates with disc injury, posterior column fractures or spinal cord injuries. As for patients with lower cervical unilateral facet locking combined with traumatic cervical disc herniation, the anterior reduction and decompression is the choice of treatment. While for those with-out disc herniation, traction or posterior open reduction and fixation can be carried out directly.

Objective To evaluate the mid-term clinical effects and the imaging changes of Coflex interspinous dynamic internal fixation for low back pain. Methods From February 2007 to June 2009,Coflex interspinous dynamic internal fixation was performed in a consecutive 45 patients. They included 26 males and 19 females, with an average of 51.4 years ranging in age from 45 to 70 years. Thirty-two cases were in L4.5 level, 11 in L5S1 level and 2 in both two levels. The patients were treated with limited laminectomy and implanted with Coflex device. Clinical outcomes were assessed by Oswestry disability index (ODI)scores and Japanese Orthopaedic Association (JOA) questionnaires before and after operation. The imaging examination was obtained to assess height of the intervertebral space, area of the intervertebral foramen,segment movement of the operation level, low lumbar curvature and signal of the lumbar disc on MRI. Results The follow-up time ranged from 10 to 34 months, with an average of 24 months. The ODI scores decreased significantly from 62.82±10.42 preoperatively to 11.80±3.35 postoperatively. The JOA scores were improved remarkably from 9.00±2.63 preoperatively to 24.65±1.86 postoperatively. The proportion with optimal effect was 89% (40 cases). The Cobb angle after operation of L4.5 and L5S1 level was 15.1°±3.9° and 16.3°±3.8° respectively, which was significantly decreased after operation. The range of motion of the L4.5 level increased from 6.5°±1.5° to 8.4°±2.6° while the L5S1 level did not change notedly. The heights of the dorsal intervertebral disc, distance of the spinous processes, intervertebral foramen height and area were significantly higher than those before operation. Conclusion The Coflex interspinous dynamic internal fixation is available to reserve segment movement, to increase intervertebral space height and foramen area. Meanwhile,it is effective to self-repair and prevent degeneration for the disc in adjacent levels.

Objective To develop a three-dimensional finite element model of atlantoaxial instability and compare the biomechanical properties of percutaneous anterior transarticular screw (ATS) and posterior transarticular screw (PTS) fixations.Methods A pathologic three-dimensional finite element model of atlantoaxial instability was developed from CT images of the upper cervical spine of volunteers with the aid of softwares,such as Mimics,Freeform,and Ansys.Percutaneous C1-2 ATS and PTS fixation modes were simulated and implanted to the model.Under the preload of 40 N and force moment of 1.5 Nm in anterior flexion,posterior extension,lateral bending,and axial rotation,biomechanical properties of the two fixation modes were compared.Results Under the four loading modalities,both fixation techniques provided maximal inhibition on C1-2 movement.The maximal stress for ATS was larger than that for PTS and maximal displacement for ATS was smaller than that for PTS.Conclusions Both ATS and PTS provide similar outlook and are effective to stabilize the atlantoaxial joint.Biomechanical performance of percutaneous C1-2 ATS is better than that of percutaneous C1-2 PTS.

Monoclonal antibodies (mAbs) contribute a lot to the development of numerous fields in life science as a pivotal tool in modern biological research. Development of the PCR methods and maturation of antibody production have made it possible to generate mAbs from single human B cells by single cell RT-PCR with successional cloning and expression in vitro. Compared to traditional monoclonal antibody technologies, single B cell technologies require relatively fewer cells, which are highly efficient in obtaining specific mAbs in a rapid way with preservation of the natural heavy and light chain pairing. With so many advantages, single B cell technologies have been proved to be an attractive approach for retrieval of naive and antigen-experienced antibody repertoires generated in vivo, design of rationale structure-based vaccine, evaluation and development of basic B cell biology concepts in health and autoimmunity, and prevention of infectious diseases by passive immunization and therapy for disorders. Accordingly, this review introduced recent progresses in the single B cell technologies for generating monoclonal antibodies and applications.
Antibodies, Monoclonal ; biosynthesis ; genetics ; immunology ; Antibody Specificity ; B-Lymphocytes ; cytology ; immunology ; metabolism ; Humans ; Immunologic Techniques

Objective To analyze the incidence and risk factors of contralateral radiculopathy in patients after unilateral transforaminal lumbar interbody fusion (TLIF) surgery.Methods A retrospective study was conducted within 587 patients (average age 57.1 years,range 19-71 years) who underwent unilateral TILF from January 2010 to January 2014 in our hospital,including 334 males and 253 females.Patients were divided into a symptomatic group and an asymptomatic group.The causes of contralateral neurological symptom were evaluated according to the radiological data.The difference of pre-and post-operative contralateral foramen area (CFA),segmental angle (SA) and the clinical treatment outcomes (VAS,JOA score) were compared between two groups.Results Patients were followed up for 9-21 months,average 15.1 months.Post-operative contralateral radiculopathy occurred in 28 (4.8％) of the patients who underwent unilateral TLIF,including contralateral foraminal stenosis in 16 (57.1％,16/28),screw malposition in 5 (17.9％,5/28),contralateral lateral recess stenosis and/or newly developed disc herniation in 3 (10.7％,3/28),hematoma in 1 (3.6％,1/28),cement compression in 1 (3.6％,1/28),and unknown origin in 2 patients (7.1％,2/28).Nineteen (3.2％,19/587) of the 28 patients received revision surgery because of ineffective conservative treatment.Compared with the asymptomatic group,the difference of pre-and post-operative CFA was significantly smaller (-13.8±13.2 mm2) in symptomatic group,while the SA was significantly greater (7.0°±9.8°) in symptomatic group.The JOA score at 3 months after the surgery was significantly improved in asymptomatic group (63.0％±18.1％,P＜0.05).Conclusion The incidence rate of contralateral neurological symptom was 4.8％ in the present study.The potential risk factors associated with contralateral radiculopathy were predominantly contralateral foraminal stenosis and screw malposition.The excessive restoration of SA might have an effect on contralateral nerve compression,which should arouse the attention of the surgeon.