Dynamic Radiographic Analysis of Sympathetic Cervical Spondylosis Instability

Objective To investigate the correlation between subaxial cervical spine instability and cervical spondylotic sympathetic symptoms as well as the difference of cervical spondylotic subaxial instability between male and female patients. Methods We analyzed retrospectively 318 surgical cases of cervical spondylosis treated at Department of Orthopedic Surgery of Peking Union Medical College Hospital between July 2003 and December 2007. All cases were divided into group A without sympathetic symptoms (n=284) and group B with sympathetic symptoms (n=34). Angular and horizontal translation values between two adjacent vertebral bodies from C2 to C7 were measured separately on hyperflexion and hyperextension lateral cervical spine radiographs. Fisher's exact test was used to evaluate the correlation between subaxial cervical instability and sympathetic symptoms. Intragroup correlation between patient gender and subaxial cervical instability was also evaluated. Results Subaxial instability incidences in groups A and B were 21.8% (62/284) and 55.9% (19/34), respectively. Statistical analysis indicated a definite correlation between subaxial cervical instability and sympathetic symptoms (P=0.000). Among patients without sympathetic symptoms, subaxial instability incidences were 21.4% (37/173) in males and 22.5% (25/111) in females, respectively (P=0.883). While among patients with sympathetic symptoms, subaxial instability incidences were 27.3% (3/11) in males and 69.6% (16/23) in females, respectively, indicating significant difference (P=0.030). Subaxial instability was most commonly seen at C4-C5 intervertebral space in sympathetic cervical spondylosis patients. Conclusions High correlation exists between subaxial cervical spine instability and cervical spondylotic sympathetic symptoms, especially in female patients. Hyperextension and hyperflexion radiographs of cervical spine are important to assess sympathetic cervical spondylotic subaxial instability.

Clinical algorithm for preventing missed diagnoses of occult cervical spine instability after acute trauma: A case report

BACKGROUND Missed or delayed diagnosis of cervical spine instability after acute trauma can have catastrophic consequences for the patient,resulting in severe neurological impairment.Currently,however,there is no consensus on the optimal strategy for diagnosing occult cervical spine instability.Thus,we present a case of occult cervical spine instability and provide a clinical algorithm to aid physicians in diagnosing occult instability of the cervical spine.CASE SUMMARY A 57-year-old man presented with cervical spine pain and inability to stand following a serious fall from a height of 2 m.No obvious vertebral fracture or dislocation was found at the time on standard lateral X-ray,computed tomography,and magnetic resonance imaging(MRI).Subsequently,the initial surgical plan was unilateral open-door laminoplasty(C3-7)with alternative levels of centerpiece mini-plate fixation(C3,5,and 7).However,the intraoperative C-arm fluoroscopic X-rays revealed significantly increased intervertebral space at C5-6,indicating instability at this level that was previously unrecognized on preoperative imaging.We finally performed lateral mass fixation and fusion at the C5-6 level.Looking back at the preoperative images,we found that the preoperative T2 MRI showed non-obvious high signal intensity at the C5-6 intervertebral disc and posterior interspinous ligament.CONCLUSION MRI of cervical spine trauma patients should be carefully reviewed to detect disco-ligamentous injury,which will lead to further cervical spine instability.In patients with highly suspected cervical spine instability indicated on MRI,lateral X-ray under traction or after anesthesia and muscle relaxation needs to be performed to avoid missed diagnoses of occult cervical instability.

SELECTION OF SURGICAL APPROACH TO TREAT TRAUMATIC INSTABILITY OF SUBAXIAL CERVICAL SPINE

Objective To evaluate the clinical outcomes of surgical therapy in treating traumatic instability of subaxial cervical spine through either anterior or posterior approach. Methods According to the Allen-Fergurson's classification, we retrospectively studied 42 cases of traumatic instability of subaxial cervical spine through either anterior or posterior surgical reconstruction. Patients requiring approach for either reduction or decompression were not included. Results The average follow-up interval was 3 years and 2 months. The anterior and posterior reconstructions were 24 and 18 cases, respectively. Before operation, the average scores of JOA and VAS were: 12.1 and 6.9 for anterior group, and 12.3 and 7.2 for posterior group. At the final assement, the scores of JOA and VAS improved to 16.0 and 2.2 for anterior group, and 15.7 and 2.6 for posterior group. The average ASIA motor scores of anterior and posterior group improved to 68.2 and 65.5 at the final follow-up from 58.4 and 59.7 before operation, respectively. The ASIA grade (A-E) was converted to a numeric score. The average scores before operation in the anterior and posterior group were 3.3 and 3.4, and increased to 3.8 and 3.7 at the final follow-up. After operation, there were different extent improvements of average radiological parameter, such as Cobb angle, vertebral body translation and disc height ratio. The average operation time and blood losing were 122 min and 125 mL for anterior group, and 153 min and 287 mL for posterior group. Fusion was achieved in all patients and 4 and 2 complications occurred at the anterior or posterior group. Conclusion The results showed that there were no obvious difference in parameters, such as neurological assements, functional grades, fusion rate, operation time and blood losing, between anterior and posterior group, except the virtues of anterior group in reconstruction and maintaining physiologic cervical lordosis and intervertrbal disc height occurred.

Free-hand cervical pedicle screw fixation for upper cervical fracture and instability

Objective To evaluate the clinical effect of the free-hand cervical pedicle screw fixation in treatment of the upper cervical fracture and instability. Methods A retrospective review was performed on 15 patients

Therapeutic strategy for traumatic instability of subaxial cervical spine

Background A simple, safe and effective therapeutic strategy for traumatic instability of the subaxial cervical spine, as well as its prognostic assessment, is still controversial. Methods The therapeutic options for 83 patients of traumatic instability of the subaxial cervical spine, whose average age was 35 years, were determined, according to the Allen-Ferguson classification, general health and concomitant traumatic conditions, neurological function, position of compression materials, concomitant traumatic disc herniation/damage, concomitant locked-facet dislocation, the involved numbers and position, and the patients＇ economic conditions. An anterior, posterior or combination approach was used to decompress and reconstruct the cervical spine. No operations with an anterior-posterior-anterior approach were performed. Results The average follow-up was three years and nine months. Distraction-flexion and compression-flexion were the most frequent injury subtypes. There were 46, 28 and 9 cases of anterior, posterior and combination operations, respectively. The average score of the Japanese Orthopaedics Association, visual analog scale and American Spinal Cord Injury Association （ASIA） motor index improved from 11.2, 7.8 and 53.5, respectively, before operation, to 15.3, 2.6 and 67.8, respectively, at final follow-up. For incomplete spinal cord injury （SCI）, the average ASIA neurological function scale was improved by 1-2 levels. Patients with complete SCI had no neurological recovery, but recovery of nerve root function occurred to different extents. After surgery, radiological parameters improved to different extents. Fusion was achieved in all patients and 12 developed complications. Conclusions The best surgical strategy should be determined by the type of subaxial cervical injury, patients＇ general health, local pathological anatomy and neurological function.