ABSTRACT
Objective:To subdivide clinical classification of refractory atlantoaxial dislocation, and evaluate the reliability of new subdivide clinical classification of refractory atlantoaxial dislocation.Methods:From January 2010 to December 2018, 48 patients with refractory atlantoaxial dislocation were treated, including 19 males and 29 females, aged 16 to 65 years, with an average of 39.2±13.3 years. According to the changes of relative anatomical position of C 1 and C 2 under general anesthesia with heavy traction of 1/6 body weight, subdivide clinical classification of refractory atlantoaxial dislocation were proposed, and refractory atlantoaxial dislocation was divided into traction loosening type (atlantoaxial angle≥5°) and traction stabilization type (atlantoaxial angle<5°). The traction loosening type was directly reduced by posterior atlantoaxial screw-rod fixation and fusion without anterior or posterior soft tissue release. For traction stabilization type, transoral soft tissue release was performed first, and then transoral anterior reduction plate fixation and fusion or posterior atlantoaxial screw-rod fixation and fusion were performed. Atlantodental interval (ADI) and atlantoaxial angle (AAA) were measured and collected before and after surgery to evaluate atlantoaxial reduction. The space available for the spinal cord (SAC) were measured to evaluate spinal cord compression. Visual analogue score (VAS) was used to evaluate the neck pain levels, and Japanese Orthopaedic Association (JOA) scores was used to evaluate the neurological function. American Spinal Cord Injury Association impairment scale (AIS) was used to evaluate the degree of spinal cord injury. One week, 3, 6, 12 months postoperatively and the annual review of the X-ray and CT scan were checked, in order to evaluate the reduction, internal fixation and bone graft fusion. Results:Among all 48 cases, 22 cases were traction loosening type, of which posterior atlantoaxial screw-rod fixation and fusion were performed in 16 cases and occipitocervical fixation and fusion in 6 cases. 26 cases were traction stabilization type, and they all underwent anterior transoral release, and then, anterior TARP fixation and fusion were performed in 24 cases and posterior screw-rod fixation and fusion in the other 2 cases. X-ray, CT and MRI images and of all patients 1 week after surgery showed good atlantoaxial reduction and decompression of spinal cord. In each of the two types, there was one case lost to follow-up. For 46 cases in follow-up, the follow-up time ranged from 6 to 72 months, with an average of 38.0±17.2 months. Among 46 cases, 21 cases of traction loosening type showed that, ADI reduced from preoperative 9.9±2.2 mm to 2.3±0.9 mm at 3 months after surgery and 2.3±1.0 mm at the last follow-up, AAA increased from preoperative 57.9°±12.3° to 91.0°±2.2° at 3 months after surgery and 90.9°±2.2° at the last follow-up, SAC increased from preoperative 9.8±1.3 mm to 15.1±0.7 mm at 3 months after surgery and 14.9±0.7 mm at the last follow-up, VAS score reduced from preoperative 1.5±2.1 to 0.7±1.0 at 3 months after surgery and 0.3±0.6 at the last follow-up, and JOA score increased from preoperative 10.2±1.7 to 13.3±1.3 at 3 months after surgery and 14.9±1.5 at the last follow-up. Twenty-five cases of traction stabilization type presented that, ADI reduced from preoperative 9.7±2.0 mm to 2.1±1.4 mm at 3 months after surgery and 2.1±1.3 mm at the last follow-up, AAA increased from preoperative 55.8°±9.2° to 90.9°±1.4° at 3 months after surgery and 90.9°±1.3° at the last follow-up, SAC increased from preoperative 10.5±1.0 mm to 15.4±0.5 mm at 3 months after surgery and 14.8±2.8 mm at the last follow-up, VAS score reduced from preoperative 1.7±2.1 to 0.7±0.9 at 3 months after surgery and 0.3±0.5 at the last follow-up, and JOA score increased from preoperative 10.1±1.3 to 12.9±1.5 at 3 months after surgery and 14.4±1.3 at the last follow-up. In the traction loosening type, all the 10 grade D patients were improved to grade E at the last follow-up. In the 2 grade C patients of traction stabilization type before surgery, 1 patient was improved to grade E, 1 patient was improved to grade D, and all 11 patients with grade D were improved to grade E at the last follow-up. Bony fusion was obtained in all patients from 3 to 6 months, with an average of 4.4±1.5 months. During follow-up period, no looseness of internal fixation or redislocation happened.Conclusion:Refractory atlantoaxial dislocation can be divided into traction loosening type and traction stabilization type. For traction loosening type, satisfactory reduction can be achieved by using posterior atlantoaxial screw-rod system without soft tissue release. For traction stabilization type, anterior release is preferable, and then anterior TARP or posterior screw-rod can be used to achieve satisfactory reduction.
ABSTRACT
BACKGROUND: Axial symptoms often occur in patients after posterior cervical single-door vertebroplasty. Some studies have proposed a modified surgical method to remove C3 lamina and retain cervical semisacinous muscle on C2 spinous to reduce the occurrence of axial symptoms after surgery. OBJECTIVE: To compare the clinical effects, cervical motion range and curvature of C3 laminectomy and mini-titanium plate fixation after single-door vertebroplasty. METHODS: Totally 43 patients with cervical spondylosis were selected from the General Hospital of Southern Theater Command of PLA from June 2012 to June 2017, including 25 males and 18 females. Among them, 27 patients underwent C3-6 or C3-7 single-door mini-titanium fixation vertebroplasty as fixation group and 16 patients underwent C4-6 or C4-7 single-door mini-titanium fixation vertebroplasty through posterior approach after C3 laminectomy as resection group. Preoperatively, 6 months postoperatively and at final follow-up, JOA score, cervical motion range, and C2-7 Cobb angle were compared between the two groups. This study was approved by the Ethics Committee of General Hospital of Southern Theater Command of PLA. RESULTS AND CONCLUSION: (1) All 43 patients successfully underwent the operation without vascular or spinal cord injury. (2) JOA score was higher in the two groups at postoperative 6 months and final follow-up than that preoperatively (P 0.05). (3) Motion range in the two groups was smaller at postoperative 6 months and final follow-up than that preoperatively (P < 0.05). Motion range was smaller in the fixation group than in the resection group at postoperative 6 months and final follow-up (P < 0.05). (4) C2-1 Cobb angle in the two groups was smaller at postoperative 6 months and final follow-up than that preoperatively (P < 0.05). C2-7 Cobb angle was smaller in the fixation group than in the resection group at postoperative 6 months and final follow-up (P < 0.05). (5) There was no hypersensitivity, rejection or immune response in the two groups. (6) Results indicate that C3 laminectomy and mini-titanium plate fixation have the same effect on improving neurological function, but the removal of C3 lamina can more effectively prevent the reduction of postoperative cervical motion range and curvature.