Cervical Vertebrae ; injuries ; Humans ; Magnetic Resonance Imaging ; Prognosis ; Spinal Cord Injuries ; diagnosis ; etiology ; therapy ; Tomography, X-Ray Computed

Bone Transplantation ; Cervical Vertebrae ; surgery ; Humans ; Postoperative Complications ; diagnosis ; etiology ; surgery ; Pseudarthrosis ; diagnosis ; etiology ; surgery ; Reoperation ; Spinal Fusion

Humans ; Ossification of Posterior Longitudinal Ligament ; surgery

Animals ; Evoked Potentials, Motor ; physiology ; Male ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; Spinal Cord ; physiology

Objective To probe the biological degradation of composite bone cement of calcium phosphate and cancellous bone granules,as well as its biophysical and solidifying characteristics.Methods The specimens of composite bone cement were determined by its solidification,which were made of 2.5g calcium phosphate cement mixed either with10%,15%,20%,25%,30%or 35%bone granules of 0.5～1.0mm diameter.The cylindrical specimens of 10mm diameter and18mm length were used for biomechnical test.Furthermore,the bone defect of 5mm?5mm?6mm in12canines were made in L 3 and L 4 verte bral body through anterolateral lumbar vertebral body approach,and composite bone cement with20%bone granules and calcium phosphate cement were filled into the bone defects respectively.The bone formation was evaluated by X-ray and histological examination.Results The composite bone cement with less than20%cancellous bone granules displayed excellent solidifying character,while with the diameter of 0.5～1.0mm and the content of 15%to20%cancellous bone granules,the maximal load and com pressive strength of the composite bone cement were of no significant difference with calcium phosphate ce ment ;but the biomech nical characteristics would decrease if the diameter was1.0～2.0mm despite of the content 15%to20%gran ules.New bone formation were observed in the center of composite bone cement 2months later,and com posite bone cement were replaced mostly by new bone at4months;while in calcium phosphate cement group,only slight degradation occurred at the interface of implant material and host bone at2and4months.Conclusion The composite bone cement of calcium phosphate with20%content and0.5～1mm di am eter of can cellous bone granules can provide the ability of rapid degradation and bone formation.The re sults of study present the basic data of the reparative materials with the composite bone cement for verte-broplasty clinically.

Objective To study the prevention and treatment of complications occurring in anterior cervical spinal surgery.Methods3163cases with cervical spondylotic meylopathy,spinal injury,spinal tu-mor and spinal tuberculosis treated by anterior cervical surgery,were included in this study.Trephination,corpectomy,disectomy and debridement were used for decompression,iliac bone autograft,BAK cage,cubic shaped cages and titanium mesh cages were used for bone grafting,while anterior cervical spine locking plates were performed in some of the cases.1848cases were followed-up from6months to8years with an aver-age of 2years and3months.646cases suffered from operative complications,372cases were immediate due to anterior cervical surgery,and the incidence of morbidity was11.76%.Results26cases of transient laryn-geal nerve or superior laryngeal nerve injury recovered in4to12weeks without special treatment.Most of 16cases with cervical hemotoma were caused by bleeding of smaller blood vessels and obstruction of drainage.13cases of spinal cord or nerve root irritation or injury were treated with medicine for dehydration,12of them had good result.11cases of CSF leakage were cured with cervical spinal immobilization and moderate local compression.8cases of local infection were cured with antibiotics or combined with debride-ment and suturing.2cases of esophagus perforation were repaired and healed.8cases of grafted bone dis-placement were re-operated on the day or second day of occurring.17cases of pseudoarthritis had revision surgery.6of 35cases of adjacent segments degeneration with new symptoms of spinal cord compression were treated with anterior cervical decompression again,and had good results.Most of 342cases of iliac donor side com plications were local pain or lateral femoral cutaneous nerve injury,infection occurred in some cases.Compli cations related to instruments included10cases of BAK subsidence,1case of plate breakage,1case of screws and plate back-out and7cases of titanium mesh cage subsidence.216cases of cervical axial pain were cured3to6months later with medicine.There was1case of sudden death in this group.Conclusion Many kinds of operative complications could occur in anterior cervical surgery.A standardized procedure in diagnosis and surgery methods are the key points to decrease and prevent operative related complications.

Objective To study the characteristics of the transcranial electric stimulation(TES)-elicited motor evoked potentials(MEP)recorded from different points of the diaphragm,and to determine the optimal record- ing site in the diaphragm.Methods One EEG electrode was placed subcutaneously in the midline of the skull as stimulation electrode and another EEG electrode was inserted into hard palate submucously as cathode in 30 male rats.And single square wave electrical pulse was used for stimulation.The stimulation intensity was 15 mA,the du- ration of the pulse was 0.2 ms,and the stimulating interval was 200 ms.The concentric needle electrode were insert- ed into the following eight sites:the medial,intermediate,lateral crura of the diaphragm,the junction of the posterior axilla line and the inferior border of the eleventh rib,the junction of the anterior axilla line and the inferior border of the ninth rib,the junction of the intermediate line of the clavicle and the inferior border of the eighth rib,the junction of the para-sternal line and the inferior border of the seventh rib,the pars sternalis.The MEP was recorded from each point,respectively.The optimal sites of the diaphragm MEP were found and recorded.Results The MEPs were re- corded from each of the 8 sites of the diaphragm in all the rats after TES.There was no statistically significant differ- ence among the latencies of every site.But the amplitude varied from 6.08?0.46 mV in maximum along the inferior border of the ninth rib at the anterior line of the axilla to the minimum of O.91?0.03 mV at the pars sternalis. Conclusion It is safer to insert the needle along the inferior border of the ninth rib at the anterior line of the axilla, because there was certain distant from the folding part of the pleura and the amplitude of the recorded wave at this point is maximal.

OBJECTIVETo compare the biomechanical performances of different wires and cable fixation devices in posterior instrumentation for atlantoaxial instability, and test the effect of different fixation strengths and fixation approaches on the surgical outcomes.

METHODSSix specimens of the atlantoaxial complex (C0-C3) were used to establish models of the normal complex, unstable complex (type II odontoid fracture) and fixed complex. On the wd-5 mechanical testing machine, the parameters including the strength and rigidity of anti-rotation, change and strength of stress, and stability were measured for the normal complex, atlantoaxial instability complex, the new type titanium cable fixation system, Atlas titanium cable, Songer titanium cable, and stainless wire.

RESULTSThe strength and rigidity of anti-rotation, change and strength of stress, stability of flexion, extension and lateral bending of the unstable atlantoaxial complex fixed by the new double locking titanium cable fixation system were superior to those of the Songer or Atlas titanium cable (P<0.05) and medical stainless wire (P<0.05). Simultaneous cable fastening on both sides resulted in better fixation effect than successive cable fastening (P<0.05). Better fixation effect was achieved by fastening the specimen following a rest (P<0.05).

CONCLUSIONSThe fixation effects can be enhanced by increased fastening strengths. The new type double locking titanium cable fixation system has better biomechanical performance than the conventional Songer and Atlas titanium cables. Fastening the unstable specimens after a rest following simultaneous fastening of the specimen on both sides produces better fixation effect.

Atlanto-Axial Joint ; physiopathology ; surgery ; Biomechanical Phenomena ; Bone Wires ; Cadaver ; Humans ; Internal Fixators ; Joint Instability ; physiopathology ; surgery ; Orthopedic Fixation Devices

Objective: To study the biocompatibility of CFR/PEEK composite in bone tissue after implanted in lumbar intervertebral space and to evaluate its role in the interbody fusion compared to the allograft bone. Methods: Thirteen beagles were chosen among which 7 were implanted with the disk-like CFR/PEEK composite in the lumbar intervertebral space and the other 6 were implanted with allograft bone. X-ray, QCT and histological examination were employed at 6, 12 and 24 months postoperatively. Results: The X-ray results of fusion segment were in conformity with the QCT's as well as that of histological results. All animals obtained a complete fusion at 24 months. Histological examination revealed that the anterior soft tissue to the implant exhibited a nonspecific foreign body reaction with connective tissue embed the biomaterials. Carbon fragment were seen in the surrounding tissue and some of the debric were phagocytosed by foreign body giant cell. Histological examination of bone and material revealed that new bone grew along the hole of CFR/PEEK implant. Conclusion: CFR/PEEK has an excellent biocompatibility to bone tissue.

Whiplash injury is a common injures in our daily lives, but the mechanism of it and the best treatment is largely unknown. The development of chronic pain and disability following whiplash injury is not uncommon and results in substantial social and economic costs. Clinical manifestation and recovery time are difference, which make it difficult for doctor diagnosis and treatment. The current study have shown that the social class, severity of collision, compensation and lawsuit, physical and psychological factors were relevant predictors for the outcome of whiplash. This article is try to overview the status quo of the whiplash injury.
Cervical Vertebrae ; injuries ; Humans ; Prognosis ; Whiplash Injuries ; diagnosis ; pathology ; physiopathology ; therapy