Finite element analysis of different reconstruction methods of coracoclavicular ligament for acromioclavicular joint dislocation / 中国骨伤

OBJECTIVE@#This study aims to examine the biomechanical effects of different reconstruction methods, including single-bundle, double-bundle anatomical reconstruction, and double-bundle truly anatomical reconstruction of the coracoclavicular ligament on the acromioclavicular joint using finite element analysis, to provide a theoretical basis for the clinical application of truly anatomical coracoclavicular ligament reconstruction.@*METHODS@#One volunteer, aged 27 years old, with a height of 178 cm and a weight of 75 kg, was selected for CT scanning of the shoulder joint. Three-dimensional finite element models of single-bundle reconstruction, double-bundle anatomical reconstruction, and double-bundle truly anatomical reconstruction of coracoclavicular ligament were established by using Mimics17.0, Geomagic studio 2012, UG NX 10.0, HyperMesh 14.0 and ABAQUS 6.14 software. The maximum displacement of the middle point of the distal clavicle in the main loading direction and the maximum equivalent stress of the reconstruction device under different loading conditions were recorded and compared.@*RESULTS@#The maximum forward displacement and the maximum backward displacement of the middle point of the distal clavicle in the double-bundle truly anatomic reconstruction were the lowest, which were 7.76 mm and 7.27 mm respectively. When an upward load was applied, the maximum displacement of the distal clavicle midpoint in the double-beam anatomic reconstruction was the lowest, which was 5.12 mm. Applying three different loads forward, backward, and upward, the maximum equivalent stress of the reconstruction devices in the double-beam reconstruction was lower than that in the single-beam reconstruction. The maximum equivalent stress of the trapezoid ligament reconstruction device in the double-bundle truly anatomical reconstruction was lower than that in the double-bundle anatomical reconstruction, which was 73.29 MPa, but the maximum equivalent stress of the conoid ligament reconstruction device was higher than that of the double-bundle anatomical reconstruction.@*CONCLUSION@#The truly anatomical reconstruction of coracoclavicular ligament can improve the horizontal stability of acromioclavicular joint and reduce the stress of the trapezoid ligament reconstruction device. It can be a good method for the treatment of acromioclavicular joint dislocation.

The clinical features and surgical treatment strategies of cervical kyphosis / 中华外科杂志

<p><b>OBJECTIVE</b>To analyze the clinical characteristics and the surgical treatment strategy of cervical kyphosis.</p><p><b>METHODS</b>From March 2006 to October 2009, 31 cases of cervical kyphosis were treated. According to the clinical features and imaging findings, different treatment methods were used. There were 9 patients in operation group, including 4 male and 5 female patients, aged from 17 to 72 years (average age of 35 years). Among them, 5 cases were idiopathic kyphosis and 4 cases were caused by laminectomy or other reasons. There were 22 patients in conservative treatment group, including 11 male and 11 female patients, aged from 14 to 40 years (average age of 29 years), who were all idiopathic cervical kyphosis. Before and 1 week after operation, clinical assessment were taken for the patients in operation group using Spinal Cord Injuries Classification Standard of American Spinal Injury Association (AISA). During the periodic review, the anteroposterior, normal sagittal films of cervical spine were taken. At 1 week and every 6 months after operation, MRI films were also taken. These films were studied to evaluate the effects of the operations. In the conservative group, assessment of treatment results by studying anteroposterior and normal lateral views of cervical spine were were taken every month. The clinical characteristics and the surgical treatment strategies of these patients were analyzed.</p><p><b>RESULTS</b>In operation group, 9 cases were followed up for 6 to 18 months, all patients did not failed in internal fixation and fusion. AISA neurological score and neurological function significantly improved. Three days after operation the average Cobb angle was -1.29 ° (preoperative 54.24 °). In conservative group, the average Cobb angle was -5.41 ° (before treatment 11.20 °) 4 months after the treatment. The symptoms of neck shoulder and back pain disappeared, and all patients were followed up for 3 to 24 months, with no recurrence of symptoms.</p><p><b>CONCLUSIONS</b>In the early period of cervical kyphosis, adopt postural therapy, plaster braces to correct an imbalance in cervical spine biomechanics can prevent deformity development. According to patients' clinical characteristics, choosing individual treatment programs can correct the severe cervical kyphosis and achieve good outcome.</p>

The surgical treatment of severe adolescent idiopathic cervical kyphosis / 中华外科杂志

<p><b>OBJECTIVE</b>To summarize the clinical characteristics of severe adolescent idiopathic cervical kyphosis and the operation method.</p><p><b>METHODS</b>A retrospective study was performed in 12 adolescent patients with severe cervical kyphosis treated from July 2003 to January 2007. Preoperative the Cobb angle of kyphosis range from 55 degrees to 73 degrees (average 61 degrees ). According to the angles between the posterior vertebral body tangents at every involved level on lateral cervical radiograph in extension, the osteotomy angles and range of lamina and facet were decided. The anterior release and posterior osteotomy were performed firstly. Then skull traction was maintained in order to correct the deformity as long as possible, fusion and internal fixation was completed after 7-10 days. The cervical coronal and sagittal planes X-rays and the MR were hold after operation 3 days, 3 months, 6 months, 1 year and 2 years. At the same time the treatment result, bone fusion and the instrumentation were followed up, and the symptoms were compared between pre-operation and post-operation.</p><p><b>RESULTS</b>The defect appearance of the patients was improved significantly, with the total disappearance of neck pain and improvement of nerve function. Post-operational cervical spine MR showed that the physiological curve of cervical spine was restored, cerebral spinal fluid line was clear in the kyphosis area and no spinal cord compression was found. X-ray imaging of post-operation 3 d showed that Cobb angle ranged from -12.3 degrees to 11.2 degrees with an average of -2.0 degrees . Beside one patient's AISA score was D, other patient's AISA score was E.</p><p><b>CONCLUSIONS</b>The severe adolescent idiopathic cervical kyphosis has its own clinical manifestation. It is an ideal treatment to completely assess the deformity, have staging operation and skull traction between two operations.</p>

Clinical research of delayed hyperextension injury concomitance spinal cord injury of cervical spine / 中华外科杂志

<p><b>OBJECTIVE</b>To discuss Clinic feature and turnover of delayed hyperextension injury concomitance spinal cord injury of cervical spine.</p><p><b>METHODS</b>The clinic data of 30 patients delayed hyperextension injury of cervical spine were reviewed and analyzed. Course of disease was from 3 months to 8 years. Thirty patients were divided into three groups according to course of disease. The first group, 3 - 6 months, 17 cases; the second group, 6 - 12 months, 8 cases; the third group, 12 months-8 years, 5 cases. Neurological function improvement rates were evaluated according to the JOA scores at preoperative, 3 months and 1 year post operation, and complications were observed in three groups. Twenty-six cases were treated with anterior decompression, bone graft and plate fixation. Four cases were treated with posterior decompression, bone graft and plate fixation.</p><p><b>RESULTS</b>The patient number of the three group exist with statistical significance. Thirty patients were followed up for 18 - 39 months, 23 months on average. Neurological function recovery rates were 23.8% in the first group, 53.9% in the second group and 54.3% in the third group at 1 year post operation. JOA scores of the first group and the second group with statistical significance at 3 months and 1 year post operation. JOA scores of the first group and the third group with statistical significance at 3 months and 1 year post operation. JOA scores of the second group and the third group without statistical significance at 3 months and 1 year post operation.</p><p><b>CONCLUSIONS</b>Incidence of hyperextension injury associated with spinal cord injury of cervical spine would degrade along with course of disease prolong. If delayed spinal cord injury occurred earlier, the patient's condition was severer and badly improvement rate.</p>

Sagittal diameters measurements on MR of the cervical spinal cord in normal subjects / 中华外科杂志

<p><b>OBJECTIVE</b>To offer normal reference of diameter of the cervical spinal cord and available diameter of cervical spinal canal and to screen scientific radiographic criteria to define and quantify cervical spinal cord disease.</p><p><b>METHODS</b>The magnetic resonance images of 120 normal people had been measured. The data of diameters of cervical spinal cord, CSF, M, the ratio of diameters of cord and CSF, and the ratio of diameters of cord and M had been collected and statistical analysis was made. And the relationships between the data above and each of gender, the length of C-spine and age were evaluated. In addition, the ratio of diameters of cord and CSF, and the ratio of diameters of cord and M was evaluated.</p><p><b>RESULTS</b>The study showed that in healthy people, the diameters of cervical spinal cord, CSF and M was larger in the males than in the females, decreased with age, and increased with the length of C-spine but the diameter of CSF. And the ratio of diameters of cord and CSF increased with age and not affected by the length of C-spine. However, the ratio of diameters of cord and M was not affected by age and the length of C-spine.</p><p><b>CONCLUSION</b>The ratio of diameters of cord and M is not affected by individual variation and can be used to evaluate cervical spinal cord atrophy, compression and impaired in patients with cervical myelopathy and can be important information in looking for clinically critical points.</p>