Jeff S. Silber

Post-traumatic Spinal Deformity

There are approximately 50,000 fractures to the bony spinal column each year in the United States. The vast majority of unstable spinal injuries are recognized early and managed appropriately. Rarely, the initial treatment may have been inadequate, or in less obvious injuries, less aggressive immobilization techniques may have been chosen. This along with continued exposure to physiologic stresses may lead to a gradual post-traumatic deformity that may further impede the functional as well as emotional status of these often already compromised patients. The management of post-traumatic deformity can be extremely challenging. A post-traumatic kyphotic deformity may occur in the cervical, thoracic, thoracolumbar, or lumbar spine, and once appropriate imaging studies are obtained, careful surgical considerations must be undertaken. Surgical intervention is considered if the kyphotic deformity is progressive over time or there is new onset or progression of a neurologic deficit. Surgical procedures include either a posterior or anterior only approach or any variation of a combined anterior or posterior procedure. In most cases a posterior only fusion is often insufficient for optimal correction and stabilization. Although the majority of patients developing a post-traumatic deformity usually occur after spinal column trauma initially treated nonoperatively, several miscellaneous causes of post-traumatic deformity may occur after surgery. These include nonunion, implant failure, Charcot spine, and technical error. The overall outcome after the surgical management of post-traumatic deformity has been satisfactory with better outcomes in the patients treated earlier as opposed to later. Operative complications include the increased risk of neurologic injury because of the draping of the neural elements over the anterior vertebral elements, any pre-existing spinal cord injury, and possible scarring with cord tethering. Trauma to the spinal cord and column is a devastating injury that may be fraught with many complications including post-traumatic deformity. Certainly, the best treatment is prevention with close follow-up and early intervention when needed. Once present, the treatment of post-traumatic deformity follows basic biomechanical principles consisting of re-establishing the integrity of the compromised spinal columns so that spinal stability can be restored.

Measurement variability in the assessment of sagittal alignment of the cervical spine: a comparison of the gore and cobb methods.

Background: Reconstructive procedures of the cervical spine are being performed with increasing frequency. Maintenance of physiologic sagittal alignment is an essential component of reconstructive procedures of the spine. Two methods exist for measuring sagittal alignment in the cervical spine: the Gore and Cobb methods. An experimental study comparing Gore and Cobb measurement techniques for nonspondylotic and spondylotic cervical spines was conducted. The objectives were to assess the intra- and interobserver variability of both the Gore and the Cobb methods of measurement to determine the most reproducible technique for assessing sagittal alignment of the cervical spine. Methods: With use of C3 and C7 as the end vertebrae, lateral radiographs of 20 nonspondylotic (group 1) and 20 spondylotic (group 2) cervical spines were measured by the Gore and Cobb methods on three different occasions by three orthopaedic surgeons with different levels of experience. Results: For group 1, there was less intra- and interobserver variability for the Gore method than for the Cobb method (P < 0.05). Group 2 measurements were also less variable for the Gore method, although this was not statistically significant. Pooling all three observers, 95% confidence limits for intra- and inter-observer variability for the Gore method were 3° and 6° for group 1 and 4° and 7° for group 2, respectively. For the Cobb method, corresponding values were 4° and 9° for group 1 and 5° and 9° for group 2. Overall, intraobserver measurements were less variable than interobserver measurements (P < 0.01). There were no significant differences in variability based on experience level. Conclusion: Measurements of cervical spine sagittal alignment by the Gore method are more reproducible than by the Cobb method.

Pediatric Spinal Cord Injury

Significant differences exist in the anatomy and biomechanics of the pediatric spine in comparison to the adult spine. These unique anatomical characteristics and behavioral differences predispose the developing child to unique spinal injury patterns. These differences must be considered when managing spinal and spinal cord injuries (SCIs) in the pediatric population. Children less than 8 years of age are more prone to upper cervical spine injuries. After this, the maturational growth and development with regard to spinal anatomy reflect the transition to injury patterns characteristic of the adult patient. Although the prevalence of SCIs is lower in children, diagnosing subtle spinal injuries is often more difficult. This is especially true in light of the often unappreciated radiographic differences between an immature and mature spinal axis and the difficulty in obtaining an accurate physical examination in the child. The increased healing potential of the pediatric osteoligamentous structures represents another important and unique characteristic of the immature spine. Nonoperative strategies using various forms of external immobilization for injury patterns requiring surgical intervention in the adult may often be used with success in the pediatric population. Surgery on the growing spine, however, invokes concern regarding the potential for subsequent growth abnormalities, which is compounded by any disturbance related to the initial trauma. This article provides a review of the unique aspects of pediatric spinal anatomy, SCI mechanism patterns, and treatment options available for pediatric spine injuries along with their documented long-term outcomes.

Resolution of pronounced painless weakness arising from radiculopathy and disk extrusion.

Lipetz JS, Misra N, Silber JS: Resolution of pronounced painless weakness arising from radiculopathy and disk extrusion. Am J Phys Med Rehabil 2005;84:528–537. In this retrospective, consecutive case series, we report the nonsurgical and rehabilitation outcomes of consecutive patients who presented with pronounced painless weakness arising from disk extrusion. Seven consecutive patients who chose physiatric care were followed clinically, and strength return was monitored. Each presented with predominantly painless radiculopathy, functionally significant strength loss, and radiographic evidence of disk extrusion or sequestration. Each patient participated in a targeted strengthening program, and in some cases, transforaminal injection therapy was employed. Each patient demonstrated an eventual full functional recovery. In most cases, electrodiagnostic studies were performed and included a needle examination of the affected limb and compound muscle action potentials from the most clinically relevant and weakened limb muscle. The electrodiagnostic findings and, in particular, the quantitative compound muscle action potential data seemed to correlate with the timing of motor recovery. Patients with predominantly painless and significant weakness arising from disk extrusion can demonstrate successful rehabilitation outcomes. Despite a relative absence of pain, such patients can present with a more rapidly reversible neurapraxic type of weakness. The more quantitative compound muscle action potential data obtained through electrodiagnostic studies may offer the treating physician an additional means of characterizing the type of neuronal injury at play and the likelihood and timing of strength return.

Advances in Surgical Management of Lumbar Degenerative Disease

The past several years have seen many advances in spine technology. Some of these advances have improved the quality of life of patients suffering from disabling low back pain from degenerative disk disease. Traditional fusion procedures are trending toward less invasive approaches with less iatrogenic soft-tissue morbidity. The diversity of bone graft substitutes is increasing with the potential for significant improvements in fusion success with the future introduction of several well tested bone morphogenic proteins to the spinal market. Biologic solutions to modify the natural history of disk degeneration are being investigated. Recently, electrothermal modulation of the posterior annulus fibrosis has been published as a semi-invasive technique to relieve low back pain generated by fissures in the outer annulus and ingrowing nociceptors (intradiskal electrothermal therapy, and intradiskal electrothermal annuloplasty). Initial results are promising, however, prospective randomized studies comparing this technique with conservative therapy are still lacking. The same is true for artificial nucleus pulposus replacement using hydrogel cushions implanted in the intervertebral space after removal of the nucleus pulposus posterior or through an anterior approach. Intervertebral disk prostheses are presently being studied in small prospective patient cohorts. As with all new developments, careful prospective, long-term trials are needed to fully define the role of these technologies in the management of symptomatic lumbar degenerative disk disease.

Rheumatoid Arthritis of the Cervical Spine

This is a comprehensive review article on rheumatoid arthritis and its effect on the cervical spine. After reading this article, it is hoped the spine surgeon will develop an understanding of the epidemiology, pathophysiology, clinical signs and symptoms, laboratory evaluation, radiographic evaluation, and surgical and nonsurgical management of rheumatoid arthritis of the cervical spine.

Severe Coronary Artery Disease Presenting with a Chief Complaint of Cervical Pain

We present the case of a 49-yr-old man with cervical pain of 14 wk of duration. Physical examination and magnetic resonance imaging of the cervical spine demonstrated no neurologic abnormality or corroborative pathology. Cardiac catheterization demonstrated advanced multivessel disease. The patient underwent successful coronary bypass grafting and was symptom free 12 mo later. Spine practitioners are often consulted by the medical community to determine if a patients limb or chest complaints might be caused by a spinal pain generator. This atypical case reminds us of the overlap between cardiac and cervical symptom referral. A patient with critical cardiac ischemia can present with predominant cervical complaints.

Poster 85: Severe aortoiliac occlusive disease presenting as suspected symptomatic high lumbar stenosis: a report of 2 cases1

Abstract Setting: Outpatient physiatric spine center. Patients: 2 patients with the chief complaint of proximal thigh pain. Case Descriptions: 2 middle-aged female smokers were referred by their primary care physician with bilateral thigh pain that had persisted for several years. Each presented with a lumbar magnetic resonance imaging, which demonstrated upper lumbar stenosis. In each case, bilateral and circumferential thigh pain was described, which prohibited the patient from ambulating extended distances and was relieved through quiet standing. A detailed history and radiographic review were not convincing for a corroborative radicular stressor. Each patient was neurologically intact and had diminished lower-extremity pulses. Segmental arterial Doppler studies were performed. Assessment/Results: In each case, a markedly diminished ankle-brachial index was observed. Although a focal drop in pressure was not observed between lower-limb segments, a significant reduction was appreciated when comparing the high thigh to brachial pressure measurements. Computed tomography (CT) angiograms confirmed severe aortoiliac atherosclerotic disease. Each patient was treated with an antiplatelet agent prior to further considering aortofemoral bypass. One patient’s carotid Doppler image revealed severe bilateral occlusion that led to a prompt endarterectomy. Discussion: Neurogenic claudication can present with proximal and anterior lower-extremity pain arising from a high lumbar and stenotic radicular stressor. Vascular claudication most commonly arises from atherosclerosis obliterans, and smoking remains a primary risk factor. Isolated proximal limb pain with ambulation, Leriche’s syndrome, can arise from aortoiliac occlusive disease. Conclusions: Spine practitioners are often consulted to determine if a patient’s limb complaints are arising from a spinal pain generator. These atypical cases highlight a less common pain distribution in the vascular patient, the symptomatic overlap between neurogenic and vascular claudication, and the challenges that arise when evaluating the patient with combined disease.