Anterior Decompression In Patients Research Articles

Vertebral Body Sliding Osteotomy for Cervical Myelopathy With Rigid Kyphosis.

Cervical spondylotic myelopathy is surgically demanding when associated with rigid kyphosis. Posterior surgery cannot restore cervical lordosis, and adequate decompression is not possible with rigid kyphosis. Vertebral body sliding osteotomy (VBSO) is a safe and novel technique for anterior decompression in patients with multilevel cervical spondylotic myelopathy. It is safe in terms of dural tear, pseudarthrosis, and graft dislodgement, which are demonstrated at high rates in anterior cervical corpectomy and fusion. In addition, VBSO is a powerful method for restoring cervical lordosis through multilevel anterior cervical discectomy and fusion above and below the osteotomy level. It may be a feasible treatment option for patients with cervical spondylotic myelopathy and kyphotic deformity. This is a technical note and literature review that describes the procedures involved in VBSO.

Improvement in cervical lordosis and sagittal alignment after vertebral body sliding osteotomy in patients with cervical spondylotic myelopathy and kyphosis.

Vertebral body sliding osteotomy (VBSO) is a safe, novel technique for anterior decompression in patients with multilevel cervical spondylotic myelopathy. Another advantage of VBSO may be the restoration of cervical lordosis through multilevel anterior cervical discectomy and fusion (ACDF) above and below the osteotomy level. This study aimed to evaluate the improvement and maintenance of cervical lordosis and sagittal alignment after VBSO. A total of 65 patients were included; 34 patients had undergone VBSO, and 31 had undergone anterior cervical corpectomy and fusion (ACCF). Preoperative, postoperative, and final follow-up radiographs were used to evaluate the improvements in cervical lordosis and sagittal alignment after VBSO. C0-2 lordosis, C2-7 lordosis, segmental lordosis, C2-7 sagittal vertical axis (SVA), T1 slope, thoracic kyphosis, lumbar lordosis, sacral slope, pelvic tilt, and Japanese Orthopaedic Association scores were measured. Subgroup analysis was performed between 15 patients with 1-level VBSO and 19 patients with 2-level VBSO. Patients with 1-level VBSO were compared to patients who had undergone 1-level ACCF. C0-2 lordosis (41.3° ± 7.1°), C2-7 lordosis (7.1° ± 12.8°), segmental lordosis (3.1° ± 9.2°), and C2-7 SVA (21.5 ± 11.7 mm) showed significant improvements at the final follow-up (39.3° ± 7.2°, 13° ± 9.9°, 15.2° ± 8.5°, and 18.4 ± 7.9 mm, respectively) after VBSO (p = 0.049, p < 0.001, p < 0.001, and p = 0.038, respectively). The postoperative segmental lordosis was significantly larger in 2-level VBSO (18.8° ± 11.6°) than 1-level VBSO (10.3° ± 5.5°, p = 0.014). The final segmental lordosis was larger in the 1-level VBSO (12.5° ± 6.2°) than the 1-level ACCF (7.2° ± 7.6°, p = 0.023). Segmental lordosis increased postoperatively (p < 0.001) and was maintained until the final follow-up (p = 0.062) after VBSO. However, the postoperatively improved segmental lordosis (p < 0.001) decreased at the final follow-up (p = 0.045) after ACCF. Not only C2-7 lordosis and segmental lordosis, but also C0-2 lordosis and C2-7 SVA improved at the final follow-up after VBSO. VBSO improves segmental cervical lordosis markedly through multiple ACDFs above and below the VBSO level, and a preserved vertebral body may provide more structural support.

Incidence of C5 Palsy: Meta-Analysis and Potential Etiology

Among the proposed hypotheses for C5 palsy, the most acceptable etiologies have been the tethering effect of the spinal nerve or reperfusion injury of the spinal cord. We performed a meta-analysis to determine a potential etiology of C5 palsy. The PubMed, Embase, Web of Science, and Cochrane Library databases were searched up to 2017 for relevant studies of the incidence of C5 palsy after cervical decompression surgery. Relevant incident estimates of C5 palsy stratified by the surgical approach and underlying diagnosis were calculated using an appropriate meta-analysis. A total of 107 studies were included for our meta-analysis. The pooled incidence of C5 palsy was 0.00 (95% confidence interval [CI], 0.00-0.01) for anterior decompression in patients with radiculopathy, 0.04 (95% CI, 0.03-0.05) for anterior decompression and 0.07 (95% CI, 0.06-0.08) for posterior decompression in patients with myelopathy. A two-tailed ttest with unequal variance accepted the null hypothesis of no differences in the incidence between anterior and posterior decompression in patients with myelopathy (P= 0.999) and rejected the hypothesis of no differences in the incidence between the patients with radiculopathy and myelopathy in anterior decompression (P < 0.001). With no significant difference found in the incidence of C5 palsy between anterior and posterior cervical decompression in patients with myelopathy, the tethering effect of the spinal nerve might not be a plausible etiology for C5 palsy. In contrast, we found a significantly greater incidence of C5 palsy in patients with myelopathy compared with those with radiculopathy undergoing anterior decompression, which might support the reperfusion injury of the spinal cord as the etiology of C5 palsy.

Anterior Decompression in the Management of Unilateral Cervical Spondylotic Amyotrophy

Cervical spondylotic amyotrophy is a rare clinical condition. The purpose of this study was to investigate the effects of anterior decompression in patients with unilateral upper-extremity amyotrophy caused by cervical spondylosis. The authors retrospectively analyzed the records of 31 patients (23 men and 8 women) who underwent anterior decompressive surgery for cervical spondylotic amyotrophy at the authors' institution between 2000 and 2011. Demographic characteristics, pre- and postoperative results of imaging studies, and postoperative muscle power improvement were reviewed at a mean follow-up of 22.2 months (range, 14-36 months). Patients were divided into proximal (n=21) and distal (n=10) types according to the most severely atrophic muscle, and the 2 groups were compared statistically. The most commonly affected intervertebral level in proximal-type patients was C4-C5, whereas that in distal-type patients was C5-C6. Impingements against the ventral nerve root and anterior horn were observed in 22 and 25 cases, respectively, with 16 cases having both impingements. Eighty-one percent of proximal-type patients gained 1 or more grades of muscle power improvement on manual muscle testing, whereas 40% of distal-type patients improved. Within 15 postoperative days, 57% of proximal-type patients attained subjective or objective improvement of muscle power, whereas all distal-type patients failed to improve. Anterior decompression was effective for most patients with unilateral cervical spondylotic amyotrophy, although postoperative muscle power improvement in distal-type patients was inferior to that in proximal-type patients. Furthermore, compared with the proximal type, the distal type showed a slower postoperative recovery.

Sublabial Approach for the Treatment of Symptomatic Basilar Impression in a Patient With Klippel-Feil Syndrome

Basilar impression (BI) is an uncommon condition in which there is upward displacement of the elements forming the foramen magnum, causing translocation of vertebral elements into the brainstem. Most commonly a developmental anomaly, BI is often associated with congenital conditions such as Down syndrome. Symptomatic BI is often difficult to treat surgically secondary to the anatomic variants associated with many of the coinciding congenital syndromes. To present a feasible approach for the treatment of BI. We present an alternative surgical approach for the treatment of symptomatic BI in a 37-year-old woman with Klippel-Feil syndrome. Because of the altered anatomy, traditional approaches such as the transoral-transpharyngeal, transmandibular circumglossal, and transcervical endoscopic routes were not feasible. We chose a staged sublabial, transnasal, transpalatal route for the anterior brainstem decompression followed by posterior fixation. The patient tolerated the procedures well and at last follow-up had nearly complete resolution of symptoms. The sublabial route is an alternative approach for anterior decompression in patients with symptomatic basilar impression and altered anatomic circumstances such as that caused by Klippel-Feil syndrome.

Anterior decompression combined with corpectomies and discectomies in the management of multilevel cervical myelopathy: a hybrid decompression and fixation technique

The authors retrospectively evaluated the safety and efficacy of a decompression and fixation technique in the treatment of patients with multilevel cervical spondylotic myelopathy (CSM). The authors describe the "hybrid decompression fixation" technique, a procedure involving a combination of corpectomies and discectomies to preserve a vertebra intact within the area of the decompression, thus augmenting mechanical stability. The authors retrospectively reviewed outcomes in 25 patients with multilevel CSM in whom the hybrid technique was performed between 1999 and 2003. Twelve patients underwent a single-level corpectomy and three-level discectomies. In 13 patients a two-level corpectomy and adjacent four-level discectomies were conducted, leaving a vertebral bridge the middle. All patients underwent fusion involving placement of disc and vertebral body cages filled with autogenous local bone and supplemental anterior dynamic plate fixation. The mean preoperative Nurick grade was 3 and improvement in status was reflected by a postoperative decrease to 2.6 (p < 0.05). In one patient neurological deterioration was demonstrated. At the end of the follow-up period (mean 29 months) radiography revealed evidence of osseous fusion in 24 patients; fusion status could not be determined in one patient. No evidence of late-onset instrumentation-related failure was observed in any of the 25 patients. The authors found the hybrid technique to be safe and efficient for anterior decompression in patients with multilevel CSM. The use of this technique obviates the need for staged circumferential procedures.

Delayed Anterior Decompression in Patients with Spinal Cord and Cauda Equina Injuries of the Thoracolumbar Spine

Forty-nine patients with complete and incomplete injuries of the spinal cord or cauda equina who had undergone anterior decompression at a minimum of 3 months after injury were examined. Follow-up was from 12 months to 19 years. Postoperative neurologic improvement occurred in 46.5% of patients with incomplete injuries. If the surgery was performed less than 2 years after injury, neurologic improvement occurred in 68% with an improvement in Frankel grade of 32%. Bladder function improved in 27% of patients and if operated on less than 2 years after injury improvement occurred in 43%. Conus medullaris decompression resulted in a 50% improvement. There was an 83% improvement in the pattern of pain after decompression. Of 23 patients with preoperative spasticity, 10 improved but 6 were worse after surgery.