Atlantoaxial dislocation with high spinal cord compression is a common disease, which endangers people's health and is difficult to treat. Transoropharyngeal surgery is a very important method for the treatment of this disease. The author briefly reviews various operations of decompression and internal fixation through anterior transoropharyngeal approach and some correlative treatments conducted over the past few years. Although transoropharyngeal surgery has not been widely adopted at present, with increasing understanding of physiology and anatomy of the cranio-cervical junction, and development of microsurgical technic, and improvement in pre-vention and treatment of amplications, it has rapidly become a more acceptable approach for the treatment of atlantoaxial dislocation with cord compression. And with the application of new techniques, its treatment result will be conspicuously improved.

External fixators have been widely u sed in treatment of war trauma due to t heir small size,light weight,easy application,and convenience in transport.There are several types of military external fixato r,such as FESSA(Fixateur Externe du Service de Sant?des Arm?es),CMC(Croatian Medical Corps),Synthes and Hoffman-Ⅱ.All of these have been used on the battlefields of Rwandese War,Croatia Wa r and the first Persian Gulf War.Most of military external fixators are unilateral connectable-joint.For temp orary fixation,one bar is enough;by adding another parallel bar,the fixation can be use d for long-time fixing.Facing with a great demand of war trauma treatment ,we should develop new types of military external fixator with more simplicity and less size or weight. [

Objective To prepare recombinant human bone morphogenetic protein-2(rhBMP-2)loaded chitosan nanospheres and to evaluate their ectopic bone formation activity in vivo. Methods The rhBMP-2 loaded chitosan nanospheres were prepaid using the ionic crosslinking method with TPP as a crosslinking agent.The morphological properties and particle size distribution were evaluated by transmission electron microcopy(TEM) and particle size analyzer.An intramuscular ectopic bone formation test was carried out to compare the ectopic bone formation activity in 24 SD rabbits that were randomized into 4 even groups.rhBMP-2 loaded chitosan nanospheres (1 mg),rhBMP-2 (1 mg),chitosan nanospheres and nothing were implanted into the muscle pouch at the left thigh,respectively,in groups A,B,C and D. Results The rhBMP-2 loaded chitosan nanospheres were well distributed and spherical in shape.The average particle diameter was 230.0 nm,the entrapment efficiency was 66.87％ ± 4.58％,and the loading rate was 33.44 ± 2.29 μg/mg.The mean ALP activity was respectively 1.94 ± 0.35 kat/g,1.48 ± 0.56 kat/g,0.20 ±0.07 kat/g and 0.18 ±0.06 kat/g in groups A,B,C and D,with a significant difference between the 4 groups( F =42.959,P =0.000).The mean Ca2 + content was respectively 5.20 ± 1.42 μg/mg,3.80 ± 1.40 μg/mg,0.19 ± 0.08 μg/mgand 0.20 ± 0.08 μg/mg in groups A,B,C and D,with a significant difference between the 4 groups ( F =39.242,P =0.000).Groups A and B were obviously higher than groups C and D and group A was obviously higher than group B in terms of ALP activity and Ca2+ content. Conclusion The rhBMP-2 loaded chitosan nanospheres prepared by ionic crosslinking method show a good property and obvious ectopic bone formation activity.

Objective To evaluate the clinical effect and application value of internal fixation of Magerl combined with Brooks technique for atlantoaxial instability. Methods A total of 18 patients with atlantoaxial instability, reducible atlantoaxial dislocation with reduction after traction and irreducible atlantoaxial dislocation with traction reduction after anterior laxation were treated with internal fixation of Magerl combined with Brooks technique using autologous bone grafts. Results The patients were followed up for an average 18 months (6-36 months). Screw was probably cut into the vertebral artery in one case. The guide needle was cut into the pharynx due to incorrectly penetrating the C 1 anterior arch of atlas for 3.5 cm in one case but no early complications such as spinal cord injury and local infection occurred. The spinal cord function improvement was marked in 3 cases, good in 9, mild in 4 but unchanged in 2. No case got worse. There were no loosening or break of the screw and cable. Conclusions Combined fixation of Magerl and Brooks techniques reaches three-point fixation and improves the reduction effect. It is necessary to use the combined fixation with best biomechanical stability for atlantoaxial dislocation patient with reduction or near reduction if the structure of the posterior arch of C 1,2 is intact.

Objective To study the relevant position of atlas pedicle to axis lateral mass, set up a technique of C1 pedicle screw placement with the lateral mass of axis as an anatomic landmark, and evaluate the reliability of the present screw placement technique by clinical practice. Methods 50 paired atlas and axis specimens were used to measure the distance from the sagittal midline to the medial border, the midpoint (the middle point of the mediolateral border) and the lateral border of C1 pedicle and C2 lateral mass. Furthermore, the distance between the medial border of C1 pedicle and that of C2 lateral mass, the distance between the midpoint of C1 pedicle and that of C2 lateral mass and the distance between the lateral border of C1 pedicle and that of C2 lateral were calculated respectively. The technique of C1 pedicle screw fixation was established. Using the present landmark technique, C1 pedicle screws were placed in 6 patients of atlantoaxial instability, including 5 males and 1 female averaged 41 years old, with os odontoideum in 1, odontoid hypoplasia in 3, and old odontoid fractures in 2. Results The medial border, the midpoint and lateral border of C1 pedicle was averaged (1.37?0.51) mm, (1.60?0.61) mm and (2.15?0.60) mm medial to C2 lateral mass, respectively. The entry point of C1 pedicle screw in present technique was defined as the method of making a vertical line through the midpoint of C2 lateral mass, and the entry point was 3 mm under the cross point of the superior rim of C1 posterior arch with the vertical line. 12 C1 pedicle screws were placed exactly in all 6 patients, and no neural or vascular injury was observed. The postoperative radiographs and CT scans verified all of C1 screws with a good position. Conclusion There is a steady anatomic relation between C1 pedicle and C2 lateral mass, the C2 lateral mass could be as a convenient anatomic landmark to determine the location of C1 pedicle and the position of C1 pedicle screw entry point.

[Objective]To investigate the method of anterior transsternal approach for the patients with upper thoracic spine diseases and the clinic results.[Method]Six cases upper thoracic spinal diseases,1 case of C7/T1 grade V dislocation,1 case of T1、2 TB,2 cases of upper thoracic tumor,1 case of T2 fracture and 1 case of T2、3 disc prolapse,were treated with the anterior transsternal approach operation since Oct.2001.The lesions areas were exposed via partial or complete sternotomy.The relative articles were reviewed.[Result]The average follow-up was 12.4 months(range from 6 to 22 months,except the died one).The case of C7/T1 grade V dislocation died of respiratory tract obstruction and one case of malignant schwannoma recurred 6 months post-operation.Good results were obtained in the other 4 cases.No operative complication happened in all cases.[Conclusion]While the transthoracic lateral approach cannot expose the upper thoracic spine clearly,the anterior cervical approach cannot expose the T2、3 clearly also.The anterior transsternal approach can provide a safe access to the lesions located on the upper thoracic spine above T4.

[Objective]To discuss the surgical extension and clinical effects of CAD custom-made hemipelvic for treating malignant pelvic tumors.[Method]The pelvis model was generated with its CT data by rapid prototyping.Simulated bone resection and prosthesis design were performed on the models.Surgical extension and made hemi-pelvic were designed.Nine patients received resection of pelvic tumor and reconstruction by individualized hemi-pelvic from June 2003 to June 2007.The series comprised three males and six females,four were diagnosed having giant cell tumor,two having chordoma,two having chondrosarcoma and one having osteosarcoma.According to Enneking's division,region Ⅱ(n=3),the region Ⅱ and Ⅲ(n=5),involved region Ⅰ,Ⅱand Ⅲ(n=1).[Result]The resection of tumor the implantation of prosthesis was easily accessible.The amount of bleeding was 5700 ml on an average.One patient suffered from infection and recovered after debridement.All patients began non-weight bearing walk with double crutches 4～6 weeks after operation and gradually abandoned crutches in 4 months.Three patients had local relapse,one osteosarcoma patient died of lung metastasis at 18 months after operation,one chondrosarcoma patient relapsed locally at 13 months after operation and died at 17 months after operation.One chordoma patient relapsed locally at 6 months operation and received the second operation.It was relapsed again at 6 months after the second operation and died at 3 months.Bolt was loosened in one patient,but the patient can walk with one crutch.No loosening was found in the 5 patients.The position of bilateral hips was symmetric.[Conclusion]The surgical extension of tumor designed by computer aided technical makes thorough resection possible.The custom-made hemi-pelvic is highly similar to the pelvis of patient in appearance,which makes the operation easy and produces good clinic results.The custom-made hemi-pelvic offers a good promise for the reconstruction of pelvic malignant tumors.

Objective To study the repair of great vessels injured by firearm in extremities. Methods From May 2002 to Sep. 2005, 15 cryopreserved homologous arteries were transplanted to repair the defects of great vessels of extremities in 14 patients, including 5 cases of defect of brachial arteries, 1 case of defect of axillary artery, 1 case of popliteal artery damage and 7 cases of defect of femoral arteries. The average length of homologous arterial transplants was 9.5 cm. After operation, all the 14 patients were monitored and treated according to principles of microsurgery. Result No early reject reaction was found in all the 14 cases, and all the wounds healed after Ⅱ stage treatment. With Doppler ultrasonic examination 2-3 weeks after healing, it was proved that 100% of the vessels were patent. In 4 to 8 month follow up, the function of the extremities recovered well, and no delayed reject reaction was observed. Conclusion The vessels after cryopreservation is a suitable biomaterial in homologous transplantation for repairing the defect of great vessels of the extremities as a result of firearm injury.

To summarize the clinical results of combined transoral anterior decompression and posterior decompression and internal fixation of irreducible atlantoaxial dislocation with spinal cord compression. 12 cases of irreducible atlantoaxial dislocation with spinal cord compression were operated on with transoral anterior decompression combined with posterior decompression and occipitocervical internal fixation with occipitocervical CD rod or Cervifix. With an average of 20 month follow up, clinical cure rate was evaluated according to Symon and Lavender . Vertebral canal vector diameters in MR were measured. The results showed that the total clinical effective rate was 91.6%, and the remarkable effective rate was 50%. The average improvement rate of vertebral canal decompression was 73.6 %. These results suggest that transoral anterior decompression combined with posterior decompression and internal fixation is more suitable for irreducible atlantoaxial dislocation with spinal cord compression.

From July 1998 to May 2000, 31 cases of lumbar spondylolisthesis accompanied with lumbar stenosis were treated with spinal cord decompression, autograft interbody fusion and fixed by Dyna lok system. All the patients were followed up for 6 to 28 months, averaged 12 7 months. 29 of the 31 patients were recovered completely. 2 cases of cauda equina were recovered within 2 months. Lowback pain remained in 1 case of multi segements spondylolisthesis which had been fixed for 3 vertebrae. 1 patient accompanied with cervical spinal stenosis had some residual claudication. In conclusion, spondylolisthesis fixed with the Dyna lok system can achieve a satisfactory result.