Randolph C. Bishop, Karen A. Moore and Mark N. Hadley
✓ The authors conducted a prospective study of 132 patients requiring interbody fusion without instrumentation following anterior cervical discectomy to compare the efficacy of tricortical iliac crest allograft versus autograft fusion substrates. The objectives of the study were to assess the potential differences in interspace collapse, angulation, maintenance of cervical alignment and lordosis, and clinical and radiographic fusion success rates between the two fusion substrates. The impact of habitual cigarette smoking on fusion rates was also examined.
Autograft tricortical iliac crest bone was found to be superior to allograft bone as an interbody fusion substrate after both single- and multiple-level anterior cervical decompression procedures with respect to maintenance of cervical interspace height, interspace angulation, and radiographic and clinical fusion success rates. Cigarette consumption had a significant adverse effect on successful anterior cervical interbody fusion for both autograft and allograft substrate, an effect that was most pronounced among smokers treated with allograft bone (p = 0.004).
The case for the future role of evidence-based medicine in the management of cervical spine injuries, with or without fractures
JNSPG 75th Anniversary Invited Review Article
Mark N. Hadley and Beverly C. Walters
The authors believe that the standardized and systematic study of immobilization techniques, diagnostic modalities, medical and surgical treatment strategies, and ultimately outcomes and outcome measurement after cervical spinal trauma and cervical spinal fracture injuries, if performed using well-designed medical evidence–based comparative investigations with meaningful follow-up, has both merit and the remarkable potential to identify optimal strategies for assessment, characterization, and clinical management. However, they recognize that there is inherent difficulty in attempting to apply evidence-based medicine (EBM) to identify ideal treatment strategies for individual cervical fracture injuries. First, there is almost no medical evidence reported in the literature for the management of specific isolated cervical fracture subtypes; specific treatment strategies for specific fracture injuries have not been routinely studied in a rigorous, comparative way. One of the vulnerabilities of an evidenced-based scientific review in spinal cord injury (SCI) is the lack of studies in comparative populations and scientific evidence on a given topic or fracture pattern providing level II evidence or higher. Second, many modest fracture injuries are not associated with vascular or neural injury or spinal instability. The application of the science of EBM to the care of patients with traumatic cervical spine injuries and SCIs is invaluable and necessary. The dedicated multispecialty author groups involved in the production and publication of the two iterations of evidence-based guidelines on the management of acute cervical spine and spinal cord injuries have provided strategic guidance in the care of patients with SCIs. This dedicated service to the specialty has been carried out to provide neurosurgical colleagues with a qualitative review of the evidence supporting various aspects of care of these patients. It is important to state and essential to understand that the science of EBM and its rigorous application is important to medicine and to the specialty of neurosurgery. It should be embraced and used to drive and shape investigations of the management and treatment strategies offered patients. It should not be abandoned because it is not convenient or it does not support popular practice bias or patterns. It is the authors’ view that the science of EBM is essential and necessary and, furthermore, that it has great potential as clinician scientists treat and study the many variations and complexities of patients who sustain acute cervical spine fracture injuries.
A summary of seven cases
Mark N. Hadley, Volker K. H. Sonntag and Hal W. Pittman
✓ The suprascapular nerve, formed from the upper trunk of the brachial plexus, can be entrapped at the suprascapular notch and result in significant patient morbidity. Seven patients with suprascapular nerve palsy are presented, and their evaluation, treatment, and outcome over a mean follow-up period of 24 months are described. Six of these patients were treated surgically and one medically; all experienced good results. In a review of the relevant literature, this entity is distinguished from other causes of shoulder pain, the typical presenting signs and symptoms are outlined, and the appropriate management of these patients is addressed.
A review of 53 cases of extradural cervicomedullary compression
Mark N. Hadley, Robert F. Spetzler and Volker K. H. Sonntag
✓ The transoral-transclival surgical approach is the most direct operative approach to pathology ventral to the brain stem and superior spinal cord. In selected patients, this approach is efficacious in the treatment of extradural compressive lesions from the cervicomedullary junction to the C-4 vertebra.
The authors have used the transoral surgical approach in treating 53 patients with lesions compressing the ventral extradural brain stem or the cervical cord. The evaluation, management, and long-term outcome of these patients are described (median follow-up time 24 months). The operative morbidity rate in this series was 6%, and the operative mortality rate was zero. The authors review specific features of the transoral procedure, including methods of retraction, microsurgical techniques, and adjunctive measures to avoid cerebrospinal fluid fistulae, that contributed to these good results.
Report of 10 cases
Mark J. Cuffe, Mark N. Hadley, Guillermo A. Herrera and Richard B. Morawetz
✓ Ten patients undergoing long-term renal dialysis for end-stage renal failure developed a destructive, noninfectious spondylarthropathy. All 10 patients had biopsy-proven dialysis-associated spondylarthropathy and subsequent spinal instability secondary to beta 2-microglobulin deposition in the vertebrae, intervertebral disc spaces, and support structures of the spine. Nine patients had cervical spinal instability and one had thoracolumbar spinal instability, with resultant neural compression. In at least one patient, the spinal instability was rapidly progressive. All had received renal dialysis for 34 months or longer (mean 109 months, range 34 to 154 months). Each patient required spinal stabilization (external in seven patients, internal in three). Nine of the 10 patients underwent neural decompression and spinal stabilization and fusion procedures.
One patient's neurological condition was worse following surgery due to a postoperative cervical epidural hematoma; in the other nine patients, the presenting symptoms and signs improved. Three of these chronically ill patients did not survive their hospitalization, for a perioperative mortality rate of 30%. Death was due to cardiopulmonary arrest in two patients on Day 5 and 9 postoperatively and to sepsis in the third on Day 14. Of the seven early survivors, two additional patients died: one on Day 59 due to congestive heart failure and the other on Day 273 due to a cerebrovascular accident. Four of five patients who were followed for 8 months or longer (mean 14 months, range 8 to 20 months) had successful neural decompression and spinal stabilization procedures with evidence of stable bone fusion, indicating that these chronically ill, difficult-to-manage patients can be successfully treated. Clinicians who treat patients with renal disease and neurosurgeons who treat spinal disorders should be aware of dialysis-associated spondylarthropathy as a potential cause of degenerative vertebral column instability.
A review of 25 cases
Curtis A. Dickman, Mark N. Hadley, Carol Browner and Volker K. H. Sonntag
✓ Combination atlas-axis fractures occur relatively frequently and have a higher incidence of neurological morbidity than isolated C-1 or isolated C-2 injuries. Patients with combination C1–2 fracture-subluxation injuries should be studied with thin-section computerized tomography. Appropriate treatment is determined by the type of axis fracture present and includes surgical and nonsurgical strategies. An experience with 25 patients with combination C1–2 fractures is presented, and management and follow-up guidelines are reviewed.
Jay M. Meythaler, Anne McCary and Mark N. Hadley
✓ Twelve consecutive patients with severe spasticity and hypertonia following acquired brain injury were treated with continuous intrathecal infusion of baclofen via an implanted, programmable infusion pump—catheter system for a minimum of 3 months. In every case intrathecal baclofen therapy resulted in a statistically significant reduction in upper- and lower-extremity tone, spasm frequency, and reflexes, contributing to improved functional abilities. There were no untoward side effects or complications associated with treatment.
This preliminary assessment indicates that intrathecal administration of baclofen is effective in treating the disabling spasticity caused by acquired brain injury in selected patients.
Fernando L. Vale, Jennifer Burns, Amie B. Jackson and Mark N. Hadley
✓ The optimal management of acute spinal cord injuries remains to be defined. The authors prospectively applied resuscitation principles of volume expansion and blood pressure maintenance to 77 patients who presented with acute neurological deficits as a result of spinal cord injuries occurring from C-1 through T-12 in an effort to maintain spinal cord blood flow and prevent secondary injury. According to the Intensive Care Unit protocol, all patients were managed by using Swan—Ganz and arterial blood pressure catheters and were treated with immobilization and fracture reduction as indicated. Intravenous fluids, colloid, and vasopressors were administered as necessary to maintain mean arterial blood pressure above 85 mm Hg. Surgery was performed for decompression and stabilization, and fusion in selected cases. Sixty-four patients have been followed at least 12 months postinjury by means of detailed neurological assessments and functional ability evaluations.
Sixty percent of patients with complete cervical spinal cord injuries improved at least one Frankel or American Spinal Injury Association (ASIA) grade at the last follow-up review. Thirty percent regained the ability to walk and 20% had return of bladder function 1 year postinjury.
Thirty-three percent of the patients with complete thoracic spinal cord injuries improved at least one Frankel or ASIA grade. Approximately 10% of the patients regained the ability to walk and had return of bladder function.
As of the 12-month follow-up review, 92% of patients demonstrated clinical improvement after sustaining incomplete cervical spinal cord injuries compared to their initial neurological status. Ninety-two percent regained the ability to walk and 88% regained bladder function.
Eighty-eight percent of patients with incomplete thoracic spinal cord injuries demonstrated significant improvements in neurological function 1 year postinjury. Eighty-eight percent were able to walk and 63% had return of bladder function.
The authors conclude that the enhanced neurological outcome that was observed in patients after spinal cord injury in this study was in addition to, and/or distinct from, any potential benefit provided by surgery. Early and aggressive medical management (volume resuscitation and blood pressure augmentation) of patients with acute spinal cord injuries optimizes the potential for neurological recovery after sustaining trauma.