Anterior cervical discectomy and fusion for noncontiguous cervical spondylotic myelopathy.

BACKGROUND: Noncontiguous cervical spondylotic myelopathy (CSM) is a special degenerative disease because of the intermediate normal level or levels between supra and infraabnormal levels. Some controversy exists over the optimal procedure for two noncontiguous levels of CSM. The study was to evaluate the outcomes of the anterior cervical discectomy and fusion (ACDF) with zero-profile devices for two noncontiguous levels of CSM. MATERIALS AND METHODS: 17 consecutive patients with two noncontiguous levels of CSM operated between December 2009 and August 2012 were included in the study. There were 12 men and 5 women with a mean age of 60.7 years (range 45-75 years). Involved disc levels were C3/4 and C5/6 in 11 patients and C4/5 and C6/7 in six patients. Preoperative plain radiographs, computed tomography (CT) with 3-D reconstruction and magnetic resonance imaging (MRI) of the cervical spine were taken in all patients. All radiographs were independently evaluated by 2 spine surgeons and 1 radiologist. The outcomes were assessed by the average operative time, blood loss, Japanese Orthopedic Association (JOA) score, improvement rate, neck dysfunction index (NDI), swallowing quality of life (SWAL-QOL) score, the cervical lordosis and complications. RESULTS: The mean followup was 48.59 months (range 24-56 months). The average operative time and blood loss was 105.29 min and 136.47 ml, respectively. The preoperative JOA score was 8.35, which significantly increased to 13.7 at the final followup (P < 0.01). The NDI score was significantly decreased from preoperative 13.06 to postoperative 3.35 (P < 0.01). The operation also provided a significant increase in the cervical lordosis (P < 0.01) from preoperative 10.17° to postoperative 17.06°. The fusion rate was 94.1% at 6 months postoperatively, and 100% at 12 months after surgery. The mean SWAL-QOL score decreased from preoperative 68.06 to immediate postoperatively 65.65 and then increased to 67.65 at final followup. There was a statistically significant difference between preoperative and immediate postoperatively values (P < 0.05), but none between preoperative and at final followup (P > 0.05). Cerebrospinal fluid leak, dysphagia and radiological adjacent segment degeneration occurred in one patient, respectively. CONCLUSION: The ACDF with zero-profile devices is generally effective and safe in treating two noncontiguous levels of CSM.

A Comparison of Zero-Profile Devices and Artificial Cervical Disks in Patients With 2 Noncontiguous Levels of Cervical Spondylosis.

STUDY DESIGN: A prospective randomized and controlled study of 30 patients with 2 noncontiguous levels of cervical spondylosis. OBJECTIVE: To compare the clinical outcome between zero-profile devices and artificial cervical disks for noncontiguous cervical spondylosis. SUMMARY OF BACKGROUND DATA: Noncontiguous cervical spondylosis is an especial degenerative disease of the cervical spine. Some controversy exists over the choice of surgical procedure and fusion levels for it because of the viewpoint that the stress at levels adjacent to a fusion mass will increase. The increased stress will lead to the adjacent segment degeneration (ASD). According to the viewpoint, the intermediate segment will bear more stress after both superior and inferior segments' fusion. Cervical disk arthroplasty is an alternative to fusion because of its motion-preserving. Few comparative studies have been conducted on arthrodesis with zero-prolife devices and arthroplasty with artificial cervical disks for noncontiguous cervical spondylosis. METHODS: Thirty patients with 2 noncontiguous levels of cervical spondylosis were enrolled and assigned to either group A (receiving arthroplasty using artificial cervical disks) and group Z (receiving arthrodesis using zero-profile devices). The clinical outcomes were assessed by the mean operative time, blood loss, Japanese Orthopedic Association (JOA) score, Neck Dysfunction Index (NDI), cervical lordosis, fusion rate, and complications. RESULTS: The mean follow-up was 32.4 months. There were no significant differences between the 2 groups in the blood loss, JOA score, NDI score, and cervical lordosis except operative time. The mean operative time of group A was shorter than that of group Z. Both the 2 groups demonstrated a significant increase in JOA score, NDI score, and cervical lordosis. The fusion rate was 100% at 12 months postoperatively in group Z. There was no significant difference between the 2 groups in complications except the ASD. Three patients had radiologic ASD at the final follow-up in group Z, and none in group A. CONCLUSIONS: Both zero-prolife devices and artificial cervical disks are generally effective and safe in the treatment of 2 noncontiguous levels of cervical spondylosis. However, in view of occurrence of the radiologic ASD and operative time, we prefer to artificial cervical disks if indications are well controlled.

Factors associated with intramedullary MRI abnormalities in patients with ossification of the posterior longitudinal ligament.

STUDY DESIGN: A retrospective clinical study of 113 patients with ossification of the posterior longitudinal ligament (OPLL), who underwent either anterior or posterior surgery between 2006 and 2009. OBJECTIVE: To evaluate the risk factors affecting the intramedullary spinal cord changes in signal intensity on magnetic resonance imaging (MRI) for the patients with OPLL. SUMMARY OF BACKGROUND DATA: The relationship between the intramedullary spinal cord changes in signal intensity on MRI and neurological deficits, as well as the surgical outcomes, has been described. To obtain better prognosis, early surgery should be conducted in patients with OPLL who have potential abilities to develop intramedullary spinal cord changes in signal intensity on MRI. Various factors may be affecting the development of intramedullary spinal cord changes in signal intensity on MRI. MATERIALS AND METHODS: The clinical and radiographic data of 113 patients with OPLL who underwent either anterior or posterior surgery between 2006 and 2009 were reviewed. Age, sex, complication, mean occupying ratio of OPLL (the greatest thickness of OPLL divided by the anteroposterior diameter of the bony spinal canal), duration of symptoms, type of OPLL, preoperative Japanese Orthopedic Association (JOA) score, and range of motion of the cervical spine were collected. Logistic regression analysis was used. RESULTS: Changes in the intramedullary signal intensity on MRI were observed in 33 of the 113 patients. Statistical results show that duration of symptoms, occupying ratio of OPLL, preoperative JOA score, kyphosis, and instability of the cervical spine are the relevant risk factors for intramedullary spinal cord changes in signal intensity on MRI, with regression coefficients of 2.437, 0.953, -1.952, 2.093, and 1.516, respectively. For patients with OPLL, the longer the duration of the symptoms, or the higher occupying ratio of OPLL, or the lower preoperative JOA score, the greater the likelihood of intramedullary spinal cord changes in signal intensity on MRI. CONCLUSIONS: As intramedullary spinal cord changes in signal intensity on MRI indicated severe damage to spinal cord and poor prognosis as we described before, early surgery is suggested for patients with OPLL who manifest one of the following factors: prolonged symptoms, high occupying ratio, low preoperative JOA score, kyphosis, or instability of the cervical spine. These factors are closely related to the intramedullary spinal cord changes in signal intensity on MRI.

Segmental anterior decompression and fusion for multilevel ossification of the posterior longitudinal ligament.

The purpose of this study was to evaluate the outcome of segmental anterior decompression and fusion for multilevel ossification of the posterior longitudinal ligament. Data were collected from 23 patients with multilevel ossification of the posterior longitudinal ligament. Average operative time and blood loss were 121 minutes and 201.6 mL, respectively. The Nurick score significantly decreased from 2.7±0.9 preoperatively to 1.8±0.9 at last follow-up (P<.01). The preoperative Japanese Orthopaedic Association score was 8.2, which significantly increased to 13.8 points at last follow-up (P<.01), with an improvement rate of 64.5%. The operation also significantly increased cervical lordosis (P<.01) from 7.7° preoperatively to 13.3° postoperatively. The fusion rate was 95.7% at 6 months postoperatively, and 100% at 12 months postoperatively. The loss of cervical lordosis and height of fusion segments were 1.2° and 0.9 mm at last follow-up, respectively. No hardware complications occurred. Cerebrospinal fluid leakage occurred in 2 patients, and hematoma occurred in 1 patient who needed an emergency operation. Segmental anterior decompression and fusion was generally effective and safe in the treatment of multilevel ossification of the posterior longitudinal ligament if indications were well controlled.

Experimental study on ischemic injury of certical spinal cord after acute artery block / 中国矫形外科杂志

[Objective]To study the effect on ischemic injury of cervical spinal cord(CSC) by comparison on two different blocks of arteries supplying CSC.[Method]Forty-eight rabbits were divided into two groups: Group A,ligation and section of anterior cervical spinal cord artery(ASCA);group B ligation and section of both ACSCA and bilateral vertebral arteries before its entramce the foraman(indirect block of Anterior cervical radicular artery(ACRA).Bdood flow changes of CSC were meansured after 6 h,24 h and 72 h(each N=6) and muscle motor cooked potential(MMEP),local energy metabolism,and cell morplotogical changes of CSC were observed.[Result]In group A,blood flow of CSC was going down markedly and showed 50.2% decrease,but got partial recovery at 24 h and 72 h.Delitescence of MMEP prolongcd,ATP and EC descended profressivtly,showing an ischemic changes,In group B there showed greate,changes about every observation thay that in group A with significant difference at every time poinl between two groups(P