Objective To compare the loss of anterior column heightand cervical Cobb angle with three different types of anterior cervical discectomy and fusion(ACDF). Methods A prospective randomized study was performed on 60 patients who had undergone ACDF with the autologous iliac crest graft (group A, n=20), the autogenous bone and the anterior cervical locking plates (group B, n=20), and Syncage-C filled with the local autograft reamings (group C, n=20) from January 1998 to January 2003. The patients diagnosed as having cervical radiculopathy (RP) and cervical spondylotic myelopathy (CSM) were indicated for ACDF. Of the patients, 41 were male and 19 female with a mean age of 57 years (range, 36-68) and their average course of disease was 6.2 months (range, 1-36). There were 36 one-level and 24 two-level fusions from C3,4 to C7,T1. Radiological measurements were performed on the cervical radiographs taken before operation, 7 days and 3 months after operation, and on the last day of the follow-up; then, the height and Cobb angle of the fused segment, functional restoration, and clinical outcome were evaluated in the three groups. Results The followup of more than 2 years (range,2-7) showed that the average loss of anterior column height and Cobb angle of the fused segments in groups A and B, which had not preserved the-endplate, hada greater increase than that in group C, which had preserved the endplate. Of the patients, 12 had autograft collapse, 3 autograft displacement, and 10 postural abnormality between the fused segments, most of which happened in groups A andB. The fusion rate was 93.3% (56 cases) according the strict arthrodesis critera; their excellent and good rate in the functional assessment was 83.3% (RP 90.4%, CSM 79.5%); the overall satisfactory (excellent and good) rates in groups A,B and C were 75%, 85% and 90%, respectively. Conclusion To increase the resistance to graft subsidence, which is a major reason for narrowness of the fused segments, and to maintain normal cervical curvature, we should improve our skills of bone grafting performance, preserve the endplate, carefully evaluate the degree of osteoporosis before operation, and use anterior cervical locking plate and /or fusion with Syncage-C when necessary.
Objective To evaluate the fixation technique of using the cervical lateral mass plate in the cervical posterior approach operation. Methods Eight patients in this group were admitted from September 2001 to November 2006. Among the 8 patients, there were 6 males and 2 females, with their ages ranging from 28 to 78 years. Cervical vertebral fracture with dislocation was found in 4 patients, C2 spinal cord injury in 1, C1 fracture in 1, cervical spinal stenosis in 1, and C2-5 spinal cord neurofibroma in 1. Muscle strength 3-4. TheFrankel grading system was usedin 6 patients with traumatic injury. Before operation, Grade C was observed in 2patients，Grade D in 3，and Grade E in 1. All the operations were performed according to requirements of the Margel’s method. We positioned 40 screws in all the patients, including 4 screws at C2，6 screws at C3，12 screws at C4，4 screws at C5，4 screws at C6，2 screws at C7，and 6 screws at T1. Results The followingup for an average of 14.1 months (range,645 months) revealed that there was no malposition of the screws in the patients. One of the 8 patients developed spinal instability in the fixed segment at 3 months after operation. The headchestbrace was applied to the patient for 3 months, and the spinal fusion was achieved. The further followingup to 45 months indicated that there was no instability occurring. The remaining patients recovered to their spinal stability by the spinal fusion. The patients also recovered in their neurological function after operation. The Frankel assessment showed that 1 patient had Grade E, 3 from Grade D to Grade E, 1 from Grade C to Grade D, and 1 from Grade C to Grade E. Conclusion The cervical lateral mass plate fixation can provide the immediate and b segmental immobilization for the good cervical spine stability.
Objective To develop a high-accuracy, better-safety and low-cost cervical pedicle locator system for guiding cervical pedicle screw placement. Methods Cervical pedicle screw locator system was made of stainless steel. Ten cervical specimens from voluntary donation were divided into two groups according to compatibil ity design: control group inwhich 60 screws were planted into C2-7 by free hand; and experimental group in which 60 screws were planted into C2-7 under the guidance of three-dimensional locator system. The condition of screw insertion was observed and the accuracy was evaluated by the integrity of pedicle walls. Results In the control group, 32 screws (53.33%) were placed inside the pedicles and 28 (46.67%) were outside; 9 screws (15.00%) led to nerve root injury, 5 screws (8.33%) caused vertebral artery injury and no spinal cord injury occurred; and the qual ification ratio of screw insertion was 76.67% (excellent 32, fair 14, poor 14). While in the experimental group, 54 screws (90.00%) were placed inside the pedicles and 6 (10.00%) were outside; 1 screw (1.67%) caused vertebral artery injury and no nerve root injury and spinal cord injury occurred; and the qual ification ratio of screw insertion was 98.33% (excellent 54, fair 5, poor 1). There was significant difference between the two groups (P lt; 0.05). Conclusion Cervical pedicle screw locator system has the advantages of easy manipulation, high accuracy of screw placement and low cost. With further study, it can be appl ied to the cl inical.
Objective To evaluate the biomechanical characteristicsof titanium mesh with anterior plate fixation or ilium autograft in anterior cervical decompression.Methods Six fresh cervical spine specimens(C3-7) of young cadaver were used in the biomechanical test. After C5, C5,6 and C4-6 were given vertebrectomy,ilium autograft and titanium mesh with anterior plate fixation were performed. Their stabilities of flexion,bilateral axial rotation,the lateral bending and the extension were tested. Intact cervical spine specimens served as control group. Results Ilium autograft improved the stability of the unstable cervical vertebrae and decreased the flexion, the lateral bending or the extension, showing a significant difference when compared with control group(Plt;0.05). Whereas, axial rotational motion was decreased insignificantly(Pgt;0.05). Titanium meshwith anterior plate fixation improved the stability of the unstable spine and decreased the flexion,the bilateral axial rotation,the lateral bending or the extension, showing a significant difference when compared with control group(Plt;0.05). Conclusion The vertebrectomy and anterior cervical fusion by ilium autograft was the least stable construct of all modes tested,and the titanium mesh implantation is stabler than the intact cervical sample.
Objective To summarize the methods andskills of anterior cervical locking plate systems in clinical application and to analyze the causes of some complications as well as give some preventive or remedial countermeasures. Methods From 1998 to 2002, 159 patients with cervical spondylotic myelopathy,fracturedislocation,tumor or tuberculosis of the cervical spine were treated with anterior locking plate systems. The complications were reviewed and analyzed. Results Ten kinds of complications related to anterior locking plate systems occurred in 21 patients. Most of the complications were caused by improperly-selecting implants, experience and technique deficiency. Conclusio The important preventive or remedial countermeasures are correctly-selecting patients, meticulous preoperative preparation, properly-selecting implants, standard and skillful manipulation and rational postoperative protection.
OBJECTIVE: To discuss the value of anterior operation in fracture-dislocation of connect of cervical vertebrae and thoracic vertebrae. METHODS: From 1997, 21 patients with fracture-dislocation of connect of cervical vertebra and thoracic vertebrae were operated on. The interval between injury and operation was within 24 hours in 4 cases, 2-7 days in 9 cases, 8-14 days in 3 cases and within 4 weeks in 5 cases. The locations were C6,7 in 7 cases, C7 in 9 cases and T1 in 5 cases. The nerves function of spinal of all the cases have different degrees of injury. Classification of Frankel were the following: 3 cases of grade A, 6 cases of grade B, 9 cases of grade C, and 3 cases of grade D. The operative procedure included the following: anterior operation of cervical vertebrae; incision of most fracture vertebral body to decompress; transplantation of ilium bone grafting fusion; and internal fixation of anterior cervical vertebrae with locking-steel. RESULTS: In 21 patients, 1 died of accompanying by pulmonary infection; 20 were followed up 8 months to 3 years with an average of 21 months. All transplanted ilium had fused. The nerve function of spinal cord had recovered in different degrees(2 cases of grade A, 1 case of grade C, 9 cases of grade D and 8 cases of grade E); the turn of vertebral column was normal. No internal fixation failed. CONCLUSION: Anterior operation is a better way to treat fracture-dislocation of connect of cervical vertebrae and thoracic vertebrae with easy operation, less complications, satisfactory reduction of fracture and good stability.
Objective To investigate the feasibil ity, safety and operative techniques of percutaneous vertebroplasty (PVP) in treating osteolytic bone metastasis of cervical vertebra and reconstructing the function of cervical vertebra. Methods From March 2005 to December 2007, 10 patients with osteolytic bone metastatic carcinoma in single cervical vertebral body received PVP, including 5 males and 5 females aged 38-75 years (mean 54.5 years). Among them, 5 patients had primary lung tumor, 1 primary renal tumor, 1 primary breast tumor, 1 primary cervical tumor and 2 unknown primary lesion. The course of disease was 2-4 years. All the patients suffered from obviously cervical pain and l imitation of activity, including 4 cases of metastatic tumor of the C2 vertebral body, 2 of C3, 2 of C6 and 2 of C7. The general condition of patients was stable before operation, and no blood coagulation dysfunction, radiculalgia and spinal cord compression were detected. Lateral PVP was performed on 6 cases, approaching between the vertebral artery and the carotid sheath under CT guidance and anterolateral PVP was performed on the rest 4 cases, approaching between the trachea and the internal carotid artery under continuously X-ray fluoroscopy. The amount of bone cement injected was 3-4 mL, and the fill ing rate was 50%-100%. Results Without obvious bleeding or organ injury, the puncture was performed successfully on all the patients. Without symptom of spinal cord compression, patients suffered from pain during operation (1 case) and such compl ications noted by immediate CT or X-rays examination after operation as paravertebral epidural cement leakage (2 ases),transverse foramen cement leakage (1 case) and pinhole reflux (3 cases). The pain of patients was improved to various degree postoperatively, the visual analogue scales score was (5.9 ± 1.2) points before operation, which was changed to (2.6 ± 1.2) points at 1 hour after PVP and (1.6 ± 1.3) points at 1 week after PVP, indicating there was a significant difference between pre- and postoperation (P lt; 0.05). During the regular follow-up at 1 week, 3 and 12 months after PVP, all patients had no dislocation of cervical vertebra body, spinal cord compression and paralysis. Five patients died from multiple organ failure due to primary tumor progression, including 3 cases at 6 months after PVP and 2 at 12 months after PVP, and the rest 5 patients’ cervical pain were under control, with sound functional recovery. Conclusion PVP can rel ieve pain quickly and reinforce the stabil ity of the vertebral body, and has sl ight compl ications; the lateral approach is safe and effective.
Objective To evaluate the therapeutic effect of open-door cervical expansive laminoplasty (ELP) with anchor fixation on flurosis cervical stenosis (FCS). Methods From February 2005 to February 2006, 20 patients with FCS underwent ELP using anchor fixation (group A) and 24 patients with FCS received ELP using conventional silk thread fixation (group B). In group A, there were 11 males and 9 females aged (58.0 ± 11.2) years old, the course of disease ranged from 6 months to 5 years, and the stenosis involved 3 vertebral levels in 3 cases, 4 levels in 8 cases, and 5 levels in 9 cases, andthe sagittal diameter of the cervical spinal canal was (7.30 ± 5.23) mm. While in group B, there were 11 males and 13 females aged (61.0 ± 9.1) years old, the course of disease ranged from 5 months to 5 years, the stenosis involved 3 vertebral levels in 5 cases, 4 levels in 10 cases, and 5 levels in 9 cases, and the sagittal diameter of the cervical spinal canal was (7.11 ± 4.92) mm. No significant differences were evident between two groups in terms of the general information (P gt; 0.05). Before operation and at 24 months after operation, the nerve function was assessed by JOA score, the axial symptom (AS) was evaluated using Chiba 12-point method, and the changes of cervical lordosis index (CLI) and cervical range of motion (CRM) were detected by imaging examination. Results All wounds healed by first intention. All patients were followed up for 24 months. JOA score: in group A, it was improved from 7.4 ± 1.5 before operation to 14.6 ± 2.1 at 24 months after operation with an improvement rate of 61% ± 3%; in group B, the score was increased from 7.1 ± 2.2 to 12.6 ± 2.5 with an improvement rate of 52% ± 5%; significant differences were evident in two groups between before and after operation, and between two groups in terms of the improvement rate (P lt; 0.05). AS score: in group A, it was improved from 6.2 ± 2.1 before operation to 10.8 ± 0.3 at 24 months after operation with an improvement rate of 74% ± 4%; in group B, the score was increased from 6.3 ± 1.9 to 8.8 ± 0.5 with an improvement rate of 39% ± 3%; significant differences were evident in two groups between before and after operation, and between two groups in terms of improvement rate (P lt; 0.05). X-ray films and CT scan at 24 months after operation displayed that there was no occurrence of “breakage of door spindle” or “re-close of door” in two groups, there was no occurrence of anchor loosing in group A, and the molding of the spinal canal was satisfactory in two groups. Preoperatively, the CLI was 11.9 ± 1.9 in group A and 11.3 ± 2.2 in group B and the CRM was (39.5 ± 2.4)° in group A and (40.2 ± 1.8)° in group B. While at 24 months after operation, the CLI was 9.5 ± 2.2 in group A and 8.2 ± 2.8 in group B, and the CRM was (30.6 ± 2.0)° in group A and (28.7 ± 2.4)° in group B, suggesting there was a significant decrease when compared with the preoperative value and group A was superior to group B (P lt; 0.05). The saggital diameter of the cervical spinal canal 24 months after operation was (13.17 ± 2.12) mm in group A and (12.89 ± 3.21) mm in group B, indicating there was a significant difference when compared with the preoperative value (P lt; 0.01). Conclusion Compared with conventional silk thread fixation, ELP using anchor fixation brings more stabil ity to vertebral lamina, less invasion to the posterior muscular-skeletal structure of the cervical spine, sl ight postoperative neck AS, andsatisfactory cl inical outcomes.
Objective To explore changes in the height and width of the cervical intervertebral foramina of C6,7 before and after the C5,6 discetomy, the replacement or the anterior intervertebral fusion so as to provide the theoretical basis for the clinical practice. Methods Eleven fresh cervical spinal specimenswere obtained from young adult cadavers. The specimens of C5,6 were divided into the integrity group, the discectomy group, the artificial disc replacement group, and the intervertebral fusion group. The range of variety (ROV) of the C6,7 intervertebral foramen dimensions (height, width) before and after the loading tests (0.75, 1.50 Nm) were measured in the 4 groups. Results The C6,7 intervetebral foramen height and width increased significantly during flexion (Plt;0.01) but decreased significantly during extension (Plt;0.01). There was a significantdifference between the two test conditions in each of the 4 groups (Plt;0.01). However, in the two test conditions there was no significant difference in ROV of the C6,7 intervetebral foramen height and width during flexion and extension betweenthe integrity group, the discectomy, and the artificial disc replacement group（Pgt;0.05）, but a significant difference in the above changes existed in the intervertebral fusion group when compared with the other 3 groups (Plt;0.05). In the same group and under the same conditions, the ROV of the C6,7 intervetebral foramen height and width was significantly different in the two test conditions (Plt;0.01). Conclusion The results have indicated thatartificial disc replacement can meet the requirements of the normal cervical vitodynamics. The adjacent inferior cervical intervetebral foramen increases during flexion but decreases during extension. The intervertebral fusion is probably one of the causes for the cervical degeneration or the accelerated degeneration and for the cervical spondylotic radiculopathy and the brachial plexus compression.
Objective To evaluate surgical results of the titanium screwplate internal fixation in treatment of the lower cervical fracture dislocation. Methods From September 2001 to March 2006, 31 patients(24 males, 7 females; age range, 2063 years) with the lower cervical fracturedislocation were treated in our department. The injuries were caused by a road accident in 25 patients, a high crash in 4, and a heavy object crash in 2. The fracture dislocation occurred in the following cervical segments:C3(1 patient),C4(5 patients), C5(12 patients), C6(10 patients), and C7(3 patients). The disease course ranged from 1 to 23 days. The associated spinal nerve root injury occurred in 29 patients. The Frankle scaling revealed that 14 patients were at Grade A, 3 at Grade B, 7 at Grade C, 3 at Grade D, and 2 at Grade E (associated nerve root injury with hand and shoulder numbness). The 29 patients underwentthe spinal cord decompression, the grafting fusion of the small joints, and thelateral mass titanium screwplate internal fixation; 2 patients without nerve injury underwent only the grafting fusion of the small joints and the lateral mass titanium screwplate internal fixation. The bone fusion, cervical vertebra movement, and internal fixation condition were observed by the X-ray examinations postoperatively. The nerve function recovery was evaluated by the Frankle scaling system. Results The followedup in all the patients for 6months to 4 years revealed that the small joint fusion time was 36 months, with an average of 3.6 months. The cervical X-ray films showed that there was no instability or fracture looseness of the internal fixation at 6 months. Among the 29 patients with the spinal nerve root injury, 14 were at Grade A preoperatively but 13 were improved at Grade B and 1 at Grade C postoperatively; 3 were at Grade B preoperatively but 2 were improved at Grade C and 1 at Grade D postoperatively; 7 were at Grade C preoperatively but 3 were improved at Grade D and 4 at Grade E postoperatively; 3 at Grade D preoperatively but all the 3 were improvedat Grade E postoperatively; 2 were at Grade E preoperatively and remained unchanged postoperatively. In the 2 patients with only the nerve root injury, numbness disappeared soon after operation. Conclusion This posteriorapproach has two advantages: the mobility range of the cervical vertebra can preserved to the greatest extent because of the short segment fixation; the betterstability can obtained because of the titanium screwplate internal fixation on the cervical jointcolumn to prevent the hyperextension and hyperflexion. Therefore, the titanium screwplate internal fixation on the cervical lateral massis an effective treatment of the lower cervical fracture dislocation.