Mark Bernstein and Beverly C. Walters
Beverly C. Walters
✓ Bone grafts are usually an integral part of cervical spine fixation following spinal trauma. Unfortunately, many currently used bone graft donor sites (including the rib, iliac crest, and fibula) cause unacceptable patient morbidity, especially postoperative pain. A readily available source of autologous bone graft for posterior cervical fusion is the occipital bone. This membranous bone offers the advantage of strength and less bone resorption. It has been used at the Sunnybrook Health Science Centre for 4 years as a standard source of bone graft with no morbidity and excellent results for fusion.
Jacob R. Lepard, Beverly C. Walters and Curtis J. Rozzelle
Neurosurgery, and particularly spine surgery, is among the most highly litigated medical specialties in the US, rendering the current malpractice climate of primary importance to spine surgeons nationwide. One of the primary methods of tort reform in the civil justice system is malpractice damage capitation (or “caps”); however, its efficacy is widely debated. The purpose of this article is to serve as a review for the practicing neurosurgeon, with particular emphasis on short- and long-term effects of damage caps and on the current debate regarding their utility, based on a systematic review of the literature.
The Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines for systematic review of observational studies were used in the design of the study. Multiple medical and legal online databases (MEDLINE, Scopus, EMBASE, and JSTOR) were queried using the key words “malpractice” and “damage capitation” for articles from 2000 to 2014. A total of 96 abstracts were screened for inclusion and exclusion criteria. Of these, 22 articles were reviewed in full and another 15 were excluded for study design or poor quality of data. Five more studies were added after cross-checking the bibliographies of the included articles. The resulting 12 articles were evaluated; relevant data were extracted using a standardized metric.
Five studies were found showing varying effects of capitation on physician availability, with only 1 of these specifically showing increased availability of neurosurgery and elective spine coverage in states with capitation. Four studies demonstrated that capitation overall succeeds in decreasing jury awards and frequency of claims filed. Last, 3 studies were found showing an overall decrease in malpractice premiums for states that passed damage capitation.
There is evidence in the literature showing that total and noneconomic damage capitation has the potential to improve the practice environment for neurosurgeons nationwide. Additionally, there are other factors that affect malpractice premium rates, such as the investment markets, which are not affected by these laws. All of these are important for spine surgeons to consider and be aware of in advocating for appropriate reform measures in their states.
Mark A. Mittler, Beverly C. Walters and Edward G. Stopa
✓ This study provides an objective assessment of the reliability of histological grading of astrocytoma specimens obtained using stereotactic biopsy. Pathological diagnosis of brain tumors provides an index of disease severity and guides clinical practice in their treatment. It also functions as the gold standard in assessing the validity of diagnostic tests such as magnetic resonance imaging. Often diagnoses are made from biopsy material obtained using stereotactic technique. The current study was designed to evaluate this gold standard with regard to interobserver and intraobserver variability.
Four certified neuropathologists from academic centers in the United States and Canada were asked to grade 30 brain biopsy specimens obtained stereotactically in patients with astrocytomas. Intraobserver agreement was analyzed in individual observers by comparing their first and second readings, separated by 5 to 14 weeks. Interobserver data were analyzed by comparing initial readings across all observers for individual diagnoses. Kappa analysis was used to measure agreement beyond chance.
Intraobserver agreement was 74.73% for glioblastomas multiforme, 51.43% for anaplastic astrocytomas, and 65.22% for low-grade astrocytomas. The most common disagreements were between anaplastic astrocytomas and glioblastomas multiforme, followed by disagreements between anaplastic and low-grade astrocytomas. Interobserver agreement on initial readings was 62.41% (κ 0.39) for glioblastomas, 36.04% (κ 0.06) for anaplastic astrocytomas, and 57.14% (κ 0.48) for low-grade astrocytomas.
A significantly greater degree of reliability was seen in histopathological diagnoses of low- or high-grade astrocytomas than in those of intermediate-grade astrocytomas. Therefore, the highest variability occurs at the point of clinical decision making—namely, intermediate-grade tumors that may or may not be selected to receive adjuvant therapy. This considerable variability is an issue that needs to be recognized and further addressed by analysis of current and proposed astrocytoma grading schemes.
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.
Michael J. Glantz, Marc C. Chamberlin and Beverly C. Walters
Innovative approaches to the treatment of neoplastic meningitis are being widely tested. Unfortunately, research on diagnostic strategies and outcome measures on which any advances in treatment ultimately depend, has not been avidly pursued.
A critical review of the literature on neoplastic meningitis published since 1978 was undertaken by using MEDLINE and other English language databases. All articles addressing the issues of diagnostic or response criteria were included. Randomized clinical trials (RCTs) were emphasized. Prospectively collected data from the authors' institution correlating the results of cerebrospinal fluid (CSF) cytological examinations with Karnofsky Performance Scale (KPS) score are also discussed.
Twenty-six studies (representing 1208 patients) fulfilled search criteria. Only three were RCTs. Cerebrospinal fluid cytology was the sole diagnostic criterion in two-thirds of studies. The results of CSF cytological examination alone or in combination with other clinical or laboratory endpoints constituted the primary outcome measure in 85%. Few studies attempted to address known deficiencies in the reliability and validity of these measures, and correlation between measures was poor. Quality of life was never used as a primary outcome measure.
All currently available measurements, including CSF cytology, biochemistry, immunological, and molecular markers, neuroimaging studies, clinical examination, and survival, suffer from poor sensitivity and/or specificity, and often correlate poorly with each other. Although CSF cytological examination, performed according to a rigorous, research-supported protocol, may be the optimum diagnostic and outcome measure at this time, additional research is a prerequisite for any further advances in the clinical care of patients with neoplastic meningitis.
Influences on initial management and subsequent outcome
Beverly C. Walters, Harold J. Hoffman, E. Bruce Hendrick and Robin P. Humphreys
✓ A retrospective study of the management of patients with infected cerebrospinal fluid (CSF) shunts was undertaken, covering the 20 years from 1960 to 1979, inclusive, and involving 222 patients with 267 infections. The data were analyzed with emphasis on influences surrounding treatment choice and subsequent outcome. Treatment was classified into three major categories: medical management (antibiotics alone), surgical management (antibiotics plus operative removal of the infected shunt), and no treatment (ranging from admission and observation only to shunt revision), the diagnosis of shunt infection having been missed. Results showed surgical treatment to be more efficacious than medical or no treatment, with a higher rate of initial cure, and lower morbidity and mortality rates.
Also examined were the relationships among clinical presentation, infection rate, and results of specimens sent for culture, and initial treatment. The definitive nature of initial treatment was revealed to be directly proportional to the aggressiveness of microbiological investigation. This latter aspect was related to clinical presentation, with shunt malfunction being the least recognized symptom of shunt infection. Patients presenting with blocked shunts were less likely to receive therapy appropriate for infection than any other group, leading to the conclusion that shunt malfunction may be more specific to infection than heretofore believed.
Matthew S. Erwood, Mark N. Hadley, Amber S. Gordon, William R. Carroll, Bonita S. Agee and Beverly C. Walters
Recurrent laryngeal nerve (RLN) injury is one of the most frequent complications of anterior cervical discectomy and fusion (ACDF) procedures. The frequency of RLN is reported as 1%–11% in the literature.4,15 The rate of palsy after reoperative ACDF surgery is not well defined. This meta-analysis was performed to review the current medical evidence on RLN injury after ACDF surgery and to determine a relative rate of RLN injury after reoperative ACDF.
MEDLINE, PubMed, and Google Scholar searches were performed using several key words and phrases related to ACDF surgery. Included studies were written in English, addressed revisionary ACDF surgery, and studied outcomes of RLN injury. Statistical analysis was then performed using a random-effects model to calculate a pooled rate of RLN injury. The heterogeneity of the studies was assessed using Cochran's Q statistic and I2 statistic, and a funnel plot was constructed to evaluate publication bias.
The search initially identified 345 articles on this topic. Eight clinical articles that met all inclusion criteria were included in the meta-analysis. A total of 238 patients were found to have undergone reoperative ACDF. Thirty-three of those patients experienced an RLN injury. This analysis identified a rate of RLN injury in the literature after reoperative ACDF of 14.1% (95% confidence interval [CI] 9.8%–19.1%).
The rate of RLN palsy of 14.1% was greater than any published rate of RLN injury after primary ACDF operations, suggesting that there is a greater risk of hoarseness and dysphagia with reoperative ACDF surgeries than with primary procedures as reported in these studies.