Objective To explore the feasibilities, methods, outcomes and indications of atlas pedicle screw system fixation and fusion for the treatment of upper cervical diseases. Methods From October 2004 to January 2006, 17 patients with upper cervical diseases were treated with atlas pedicle screw system fixation and fusion. There were 13 males and 4 females, ageing 19 to 52 years. Of 17 cases, there were 14 cases of atlantoaxial dislocation(including 3 cases of congenital odontoid disconnection，4 cases of old odontoid fracture，2 cases of new odontoid fracture(typeⅡC), 3 cases of rupture of the transverse ligament, and 2 cases of atlas fracture； 2 cases of tumor of C2; 1case of giant neurilemoma of C2,3 with instability after the resection oftumors. JOA score before operation was 8.3±3.0. Results The mean operative time and bleeding amount were 2.7 hours (2.1-3.4 hours) and 490 ml (300-750 ml) respectively. No injuries to the vertebral artery and spinal cord were observed. The medial-superior cortex of lateral mass was penetrated by 1 C1 screw approximately 3 mmwithout affecting occipito-atlantal motions. All patients were followed up 3-18 months. The clinical symptoms were improved in some extents and the screws were verified to be in a proper position, no breakage or loosening of screw and rob occurred. All patients achieved a solid bone fusion after 3-6 months. JOA score 3 months after operation was14.6±2.2. JOA improvement rates were 73%-91%(mean 82%). Conclusion The atlas pedicle screw system fixation and fusion is feasible for the treatment of upper cervical diseases and has betteroutcomes, wider indications if conducted properly.
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 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 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.
Objective To study the cl inical appl ication of anchoring cervical intervertebral fusion cage (ACIFC) in anterior cervical discectomy with fusion. Methods From November 2006 to June 2007, 21 cases of degenerative cervical disease were treated with anterior cervical discectomy, bone graft by ACIFC and anchoring stators, and 28 ACIFCs were implanted. There were 12 males and 9 females aged 25-68 years old (average 47.9 years old). The course of disease rangedfrom 3 days to15 years (median 2.3 years). There were 7 patients with single-segment cervical spondylosis, 3 with two-segment cervical spondylosis, 2 with single-segment lower cervical spine instabil ity, 4 with single-segment cervical spondylosis and lower cervical spine instabil ity, and 5 with cervical disc herniation. Postoperatively, X-ray films were taken regularly to detect the fusion of bone graft and the intervertebral height of fused segment was measured. The symptoms, signs and cervical functions of patient before operation, shortly after operation and during the follow-up period were evaluated by “40 score” system. And the occurrence of postoperative axial symptom (AS) was assessed with the standard set by Zeng Yan et al. Results All incisions healed by first intention. AS occurred in 1 case 48 hours after operation and was improved from poor to good after symptomatic treatment. No other kind of compl ication was identified or reported during intra-operative and postoperative period. All the cases were followed up for 16-24 months (average 20.5 months), and fusion was reached in all the intervertebral discs. Evaluated by “40 score” system, the average score for the cervical spinal cord function before operation, shortly after operation and during the final follow-up period was 26.2, 30.6, and 35.5 points, respectively, indicating there were significant differences between different time points (P lt; 0.05). During the follow-up period of above 1 year, the average improvement rate was 67.4%. The average intervertebral height before operation, shortly after operation and during the last follow-up period were 1.9, 4.4 and 4.3 mm, respectively, showing there were significant differences between the preoperation and the immediate postoperative and last follow-up periods (P lt; 0.05). No degeneration of adjacent segment was observed during the follow-up period. Conclusion Using ACIFC in bone graft fusion and internal fixation for degenerative cervical disease is convenientand fast, has wide range of indications with satisfying cl inical effect, and can achieve obvious therapeutic effect in restoring and maintaining cervical intervertebral height.
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.
ObjectiveTo evaluate the mid-term clinical and radiological results of dynamic cervical implant (DCI) arthroplasty for degenerative cervical disc disease in Chinese population.MethodsBetween April 2010 and June 2011, 25 patients with single-segmental degenerative cervical disc disease underwent DCI replacement. Visual Analogue Scale (VAS), Japanese Orthopaedic Association (JOA) scores, Neck Disability Index (NDI) and 36-Item Short Form Health Survey Questionnaires (SF-36) were used for evaluation of neurological function and pain severity, before and after operation, and during follow-up period. Radiographic evaluation included range of motion (ROM) of C2–7, surgical segments and adjacent level, intervertebral height of the surgical segments, migration, subsidence of the implant and heterotopic ossification (HO).ResultsThe mean follow-up period was 72.3 months (ranged from 68 to 78 months). The VAS, JOA, NDI, and SF-36 mental and physical component summaries improved significantly after surgery (P<0.05) and remained stable over the whole observation period. The ROM (flexion/extension) and intervertebral height at the level treated with DCI remained at the first 2 years and partly reduced at the final follow-up. ROM for C2–7 and adjacent levels maintained during the follow-up period. DCI subsidence was observed in 11 segements, and 9 segements appeared heterotopic ossification.ConclusionsClinical efficacy of DCI arthroplasty improves and maintaines during the mid-to-long period of follow-up. HO formation is a common phenomenon, leading a dramatic decrease of ROM at index level and recurrence of neurological symptoms. Rate of implant subsidence and migration is relatively high, leaving a potential risk of symptom at index level and adjacent segment degeneration. It suggests that for patients with degenerative cervical disc disease, total disc replacement or anterior cervical discectomy and fusion is still the first choice instead of DCI arthroplasty.
ObjectiveTo observe the in vivo three-dimensional (3-D) transient motion characteristics of the subaxial cervical spine in healthy adults. MethodsSeventeen healthy volunteers without cervical spine related diseases were recruited for this study, including 8 males and 9 females with a mean age of 26 years (range, 23-41 years). The vertebral segment motion of each subject was reconstructed with CT, and Rhinoceros 4.0 solid modeling software were used for 3-D reconstruction model of the subaxial cervical spine. In vivo cervical vertebral motion in flexionextension, left and right bending, left and right rotation was observed with dual fluoroscopic imaging system (DFIS). Coordinate systems were established at the vertebral center of C3-7 to obtain the intervertebral range of motion (ROM) and displacement at C3, 4, C4, 5, C5, 6, and C6, 7. The X-axis pointed to the left along the coronal plane, the Y-axis pointed to the back along the sagittal plane, and the Z-axis perpendicular to the X-Y plane pointed to the head. The ROM along X, Y, and Z axises were represented by rotation in flexion-extension (α), in left-right bending (β), and in left-right twisting (γ) respectively, and the displacement in left-right direction (x), in anterior-posterior direction (y), and in proximaldistal direction (z), respectively. ResultsIn flexion and extension, the displacement in anterior-posterior direction of C6, 7 was significantly less that of other segments (P<0.05), but the displacements in left-right direction and in proximaldistal direction showed no significant difference between segments (P>0.05); the ROM values in flexion-extension of C4, 5 and C5, 6 were significantly larger than those of C3, 4 and C6, 7 (P<0.05), and the ROM value in left-right twisting of C4, 5 was significantly larger than those of C5, 6 and C6, 7 (P<0.05), but the ROM value in left-right bending showed no significant difference between segments (P>0.05). In left and right bending, there was no significant difference in the displacement between other segments (P>0.05) except that the displacement in anterior-posterior direction of C3, 4 was significantly larger than that of C4, 5 (P<0.05), and that the displacement in proximal-distal direction of C6, 7 was significantly less than that of C3, 4 and C4, 5 (P<0.05); no significant difference was shown in the ROM value between segments (P>0.05), except that the ROM value in left-right twisting of C3, 4 was significantly larger than that of C5, 6 and C6, 7 (P<0.05). In left and right rotation, the ROM value in left-right twisting of C3, 4 was significantly larger than that of C4, 5 and C6, 7 (P<0.05), and the displacement and ROM value showed no significant differece between other segments (P>0.05). ConclusionThe intervertebral motions of the cervical spine show different characters at different levels. And the 6-degree-of-freedom data of the cervical vertebrae are obtained, these data may provide new information for the in vivo kinematics of the cervical spine.
Objective To investigate the treatment methods and the cl inical therapeutic effects of symptomatic cervical vertebral hemangioma associated with cervical spondylotic myelopathy. Methods A retrospective analysis was performed in 18 patients (10 males and 8 females, aged 30-62 years with an average age of 45.3 years) with cervical vertebral hemangioma associated with cervical spondylotic myelopathy between January 2006 and September 2008. The disease duration was 10-26 months (mean, 15.6 months). All patients had single vertebral hemangioma, including 2 cases at C3, 3 cases at C4, 5 cases at C5, 5 cases at C6, and 3 cases at C7. The X-ray films showed a typical “pal isade” change. According to the cl inical and imaging features, there were 13 cases of type II and 5 cases of type IV of cervical hemangioma. The standard anterior cervical decompression and fusion with internal fixation were performed and then percutaneous vertebroplasty (PVP) was used. The cervical X-ray films were taken to observe bone cement distribution and the internal fixation after operation. The recovery of neurological function and the neck pain rel ief were measured by Japanese Orthopaedic Association (JOA) score and visual analogue scale (VAS) score. Results All operations were successful with no spinal cord and nerves injury, and the incisions healed well. Anterior bone cement leakage occurred in 2 cases without any symptoms. All cases were followed up 24-28 months (mean, 26 months) and the symptoms were improved at different degrees without fracture and collapse of vertebra or recurrence of hemangioma. During the follow-up, there was no implant loosening, breakage and displacement, and the mean fusion time was 4 months (range, 3-4.5 months). The JOA score and VAS score had a significant recovery at 3 months and at last follow-up when compared with preoperative values (P lt; 0.05). Based on JOA score at last follow-up, the results were excellent in 9 cases, good in 6 cases, fair in 2 cases, and poor in 1 case. Conclusion The anterior cervical decompression and fusion with internalfixation combined with PVP treatment is one of the ideal ways to treat symptomatic cervical vertebral hemangioma associated with cervical spondylotic myelopathy, which could completely decompress the spinal cord and effectively alleviate the cl inical symptoms caused by vertebral hemangioma.