For more than a century,the treatment of cervical disorders has been greatly improved.The researches for the complications of cervical spine surgery have been enhanced during the same period.The objective of this paper is to summarize the progressive results of researches on the complications of cervical spine surgery through literature review.Common surgical complications include hematoma,dural tear,postoperative infection,C5 nerve root palsy,recurrent/superior laryngeal nerve injury,axial pain,etc.Rare complications such as esophageal injury,Homer's syndrome,vertebral artery injury,dysphagia and dyspnea caused by posterior upper cervical spine surgery have also been reported in recent years.The application of cervical instruments provides great support for the improvement of clinical efficacy.However,reports about the related complications also increases year by year,including implant displacement or broken,and special complications associated with cervical artificial disc replacement.Prevention and treatment of complications is the key in clinical practice.For those complications which already have relatively clear causes,such as soft tissue or spinal cannel hematoma,recurrent/superior laryngeal nerve injury,dural tear,accurate and effective operation is highly suggested.However,there's still no standard of operating process for preventing the complications (C5 nerve root palsy,dysphagia,axial pain,etc.),whose pathogeny are still unclear,and further studies are needed in the future.Instrument related complications caused by mal-operation or abnormal patient condition can be effectively controlled through correct medical procedures.Those instrument shortcomings of material or design aspects need to be improved by the auxiliary of cutting-edge technology for further improvement of the results of clinical application.

In recent years,nano - materials have represented the superior biocompatibiliry and the arena of medical nano - materials have been extensively studied by various means all over the world. Is it possible that nano - bone implants overcome the existing limitations of the traditional bone implants for fusing operations in the future? State Food and Drug Administration (SFDA, CN) authorized the nano-bone implants- - nHA/ PA66 (YZB/0063 -2003) in 2005 but there were still lots of counterviews in this field. This review considers the advanced researches via comparing and analyzing the correlatire literatures recently.

[Objective]To investigate residual low back pain and recurrent herniation after standard discectomy for lumbar disc herniation.[Method]The long-term follow-up was analyzed in 84 patients who were selected randomly from 200 patients during a minimum of 5 years after standard discectomy,which was based on the rating of JOA and image methodology on both before and after the operations.[Result](1)Residual low back pain was found in 79.8% of the patients,of which 14.3% had severe low back pain(JOA 1).The majority of the patients with severe low back pain were under age of 35 at time of operation.(2)Twelve patients had operations again because of herniation and 1 patient had operation again because of the unstable of lumbar,who were mainly male adults under age of 50.[Conclusion]It is easier for young man to have severe low back pain and herniation recurrence.When conducting the operation for those young patients for the first time,we can consider fusion of spine properly according to their condition.

[Objective]To evaluate the restoration of the cervical curvature after segmental anterior cervical decompression.[Method]Thirty-seven patients(male 31,female 6,mean age 57.8)with cervical spondylotic myelopathy were treated by segmentai anterior decompression,JOA(17 scores)was used to evaluate the improvement of nerve function of the patients.The measurement of the lordosis was according to the Harrion posterior tangent angle which is presented on the tangent of posterior vertebral body margins of C2 and C7 in the cervical spine.E-film software was used to measure the tangent angles which were obtained by pre operation and post operation.All patients were divided into two groups in terms of the fifteen degree of lordosis of the cervical spine before the operation.[Result]All of the cases were obtained the improvement of the nerve function of the extremities.The mean JOA scores was 10.6 in pre-operation,and was 12.8 in post-operation(P

[Objective]To investigate imaginological evidences of hyperxtensive injury of cervical spine and to evaluate its use in clinics.[Method]Seventy-eight patients with hyperextension injury at cervical spine by different cause were estimated by radiograph、CT and MRI.Fifty-seven cases(73.1%) appeared with widen of soft tissue of anteriorspine,including focal type(17.5%) and diffused type(82.5%). Thirty-six cases showed avulsion fracture of anterior edge in the cervical spine. Sixty-three cases showed degeneration and developmental spinal stenosis,twenty-one cases appeared integral vertebral canal. No contrast CT scan showed osteophyte of thirty-seven cases and intervertebral discs degeneration and protrusion of twenty-one cases.Sixty-one cases(78.2%) with both disc and anterior-longitudinal-ligament injury showed by MRI,fifty-seven cases showed haematoma and oedema at the anterior of the vertebral body. Sixty-four cases accompanied with different spinal cord injury.[Result]Obvious imaging feature for hyperextension injury of cervical spine,including anterior longitudinal ligament,intervertebral disc and spinal cord were found.There exists good relationship between spinal cord injury and imaging appearance. Clinically it showed typical central syndrome,but mostly showed us neuron-functional disturbance of different degree.[Conclusion]Combining of imaginological apperarance including radiograph,CT,MRI can provide evidences for diagnosis of hyperextension and help to treat acute hyperextension cervical injury.

Objective To approach the treatment principle of lumbar spondylolisthesis with spina bifida occulta. Methods Twenty-six patients(male19,female 7,average 23.2 years old)with spondylolisthesis and spina bifida occulta were analyzed retrospectively.All cases were evaluated by radiological examinations including X-rays,computed tomography,magnetic resonance image.Based on the radiological results,the degeneration of intervertebual disc were varied by Ⅰ~Ⅴ types.Meyerdin’s score was used to evaluate the severe slip of the body of spondylolysis.At same time spina bifida occulta was divided into 4 models as follows,type A meant that the semi-lamina of sacrum was hypoplasia and still linked with spinous process;type B meant that the both sides of the lamina of sacrum was hypoplasia and the spinous process was free;type C meant that the lamina of sacrum was absent;type D meant that the spina bifida occulta was companied by other deformities such as the round formation of the end-plate of sacrum,the deformity of the transverse process of L5. Results The modality of the operations included 9 cases in single-vertabra fixation,13 cases in single-segment fixation,4 cases in two-segment fixation.All patients had been follow-up for 6~37 months(average 11.2 months).The effect of treatment was also obtained(8 in excellent,13 in good,5 in fair). Conclusions As for how to do with spondylolisthesis with spina bifida occulta(SBO),the type of SBO,degeneration scores of the disc and the degree of the slip of spondylolysis should be taken into consideration.

[Objective] To observe the structure characteristics of nano decalcified bone matrix(DBM)produced by MICROS super fine mill,and to study the nano-technologies of DBM and the biocompatibility of nano-DBM as bone graft substitutes.[Methods]Improved Urist method was used to produce DBM.The pieces of DBM was pre-porphyrizated by liquid nitrogen frozen ball mill equipment.The DBM powder were further porphyrizated by MICROS super fine mill to be nano-DBM.The structure of nano-DBM was observed by electron microscope.The experiments on acute toxicity,pyrogen and hemolysis were performed according to theTechnical Evaluation Standards of Biomedical Materials and Medical Instruments promulgated by Chinese Ministry of Health.[Results]The DBM was porphyrizated to the size of 50-200 nm in diameter.No toxicity,pyrogen nor hemolysis of nano-DBM was noted.Nano-DBM exhibited excellent biocompatibility.[Conclusion]Nano-DBM produced under the conditions of low or controlled temperature,is a kind of biomaterial which is avirulent,nonirritant,nonpyrogenic,nonimmunological reaction and reveals good biocompatibility.

Objective To explore the diagnosis and treatment of compartment syndromes of the foot after calcaneal fractures. Methods Between October 1994 and June 1999, the intracompartmental pressures of foot were measured with the Whitesides method for 98 patients with calcaneal fractures. The interstitial pressures in 9 patients averaged 46 mmHg (range from 30 to 55 mmHg). All of the 9 patients were treated by fasciotomy through a hindfoot medial incision, then each intracompartment pressure were measured,respectively. An interosseous compartment pressure still was 40 mmHg. The patient whose foot had a severe crushing injury had fasciotomy of his interosseous compartment through two dorsal forefoot incisions. After a week, the wounds were covered with a split thinkness skin graft. The calcaneal fractures were treated with open reduction and internal fixation at 2 weeks after fasciotomy through a lateral incision. Results All of the 9 patients were followed up for a mean of 2 years (range from 18 to 35 months) after injury. Two patients had occasional hindfoot and ankle pain after walking or standing for a long time. One of them decreased pin stick sensation and two point discrimination. None of the cases developed stiffness of the forefoot or claw toes, nor soft tissue contracture and motor deficit. Conclusion It should not be neglected that the compartment syndromes of the foot may occur after calcaneal fractures. Intracompartment pressure measurements should be performed to confirm the diagnosis. Fasciotomy, which could be performed through a medial hindfoot incision, is the optimal way of treatment.

BACKGROUND:Current studies on the pathogenesis of ossification of the ligamentum flavum are stil in a preliminary stage, and any single factor influencing incidence of ossification of ligamentum flavum cannot completely explain the pathogenesis of this disease. OBJECTIVE:To summarize the pathogenesis of ossification of ligamentum flavum. METHODS:A computer-based online search was conducted in PubMed, Wanfang, and CNKI databases from January 1990 to December 2015 to screen the relevant literatures regarding the pathogenesis of ossification of the ligamentum flavum using Chinese and English key words“ossification of ligamentum flavum, basic research, pathogenesis, gene, bone morphogenetic protein, osteopontin”. Consequently, 63 eligible literatures were included after the exclusion of the repetitive and old ones. RESULTS AND CONCLUSION:Current studies have shown that ossification of the ligamentum flavum is a disease that results from multiple genetic and environmental causes and is one of the main causes of spinal stenosis. Tissue degeneration, local biomechanics, genetic factors, metabolic disorders, trace elements and vascular inflammation are all shown to be involved in the pathogenesis of ossification of ligamentum flavum.

BACKGROUND:Current decelularized methods have the certain damage to the extracelular matrix and reduce the biomechanical properties of acelular scaffolds. OBJECTIVE:To explore the biomechanical properties of decelularized scaffold of lyophilized bovine tendon. METHODS:Sixty lyophilized fiber bundles from fresh flexion tendon of calf toes were randomly divided into two groups: control group and experimental group. In the experimental group, serine protease inhibitors were placed asepticaly for 24 hours at room temperature, then the samples were rinsed with PBS and transferred to the low concentration of trypsin+ethanol mixed solution to remove the cel wal without destruction of the extracelular matrix at room temperature for 5 hours; after that, the fiber bundles were cultured in DNA enzyme solution for 5 hours, finaly the acelular scaffold was completed and rinsed with PBS for 48 hours and dried at room temperature in sterile room. No treatment was done in the control group. Modulus of elasticity, durability and maximum stress were determined in the two groups. RESULTS AND CONCLUSION:Similar elastic modulus and durability were found in the two groups, but the maximum stress in the experimental group was significantly lower than that in the control group (P < 0.01). These findings indicate that the lyophilized acelular tendon fibers can mimic the biological function of bovine tendon fibers to a certain extent.