John K. Ratliff

Root and spinal cord compression from methylmethacrylate vertebroplasty.

Study Design. Case report and literature review. Objectives. Clinicians use methylmethacrylate vertebroplasty to treat vertebral hemangiomas, metastases, and osteoporotic fractures. Cement may leak out of the vertebral body and compress the adjacent spinal cord and nerve roots. We review a case of nerve-root and cord compression from methylmethacrylate extrusion during vertebroplasty. Summary of Background Data. A 50-year-old female presented with disabling thoracic back pain. A metastasis to T1 was discovered, with collapse of the vertebral body but without cord compression. Methylmethacrylate vertebroplasty was performed. After injection, portable computed tomography (CT) showed a leakage of methylmethacrylate into the C8 and T1 foramina and spinal canal. Radiculopathy and myelopathy developed. Surgical decompression using the anterior approach was necessary. Methods. Case report. Results. Early surgical intervention decompressed the neural elements and relieved the neurological deficits. Conclusions. Neurologic complications of methylmethacrylate vertebroplasty necessitate active involvement of spine surgeons in patient evaluation and management.

Comparison of ICD-9–based, retrospective, and prospective assessments of perioperative complications: assessment of accuracy in reporting

OBJECT large studies of ICD-9-based complication and hospital-acquired condition (HAC) chart reviews have not been validated through a comparison with prospective assessments of perioperative adverse event occurrence. Retrospective chart review, while generally assumed to underreport complication occurrence, has not been subjected to prospective study. It is unclear whether ICD-9-based population studies are more accurate than retrospective reviews or are perhaps equally susceptible to bias. To determine the validity of an ICD-9-based assessment of perioperative complications, the authors compared a prospective independent evaluation of such complications with ICD-9-based HAC data in a cohort of patients who underwent spine surgery. For further comparison, a separate retrospective review of the same cohort of patients was completed as well. METHODS a prospective assessment of complications in spine surgery over a 6-month period (May to December 2008) was completed using an independent auditor and a validated definition of perioperative complications. The auditor maintained a prospective database, which included complications occurring in the initial 30 days after surgery. All medical adverse events were included in the assessment. All patients undergoing spine surgery during the study period were eligible for inclusion; the only exclusionary criterion used was the availability of the auditor for patient assessment. From the overall patient database, 100 patients were randomly extracted for further review; in these patients ICD-9-based HAC data were obtained from coder data. Separately, a retrospective assessment of complication incidence was completed using chart and electronic medical record review. The same definition of perioperative adverse events and the inclusion of medical adverse events were applied in the prospective, ICD-9-based, and retrospective assessments. RESULTS ninety-two patients had adequate records for the ICD-9 assessment, whereas 98 patients had adequate chart information for retrospective review. The overall complication incidence among the groups was similar (major complications: ICD-9 17.4%, retrospective 19.4%, and prospective 22.4%; minor complications: ICD-9 43.8%, retrospective 31.6%, and prospective 42.9%). However, the ICD-9-based assessment included many minor medical events not deemed complications by the auditor. Rates of specific complications were consistently underreported in both the ICD-9 and the retrospective assessments. The ICD-9 assessment underreported infection, the need for reoperation, deep wound infection, deep venous thrombosis, and new neurological deficits (p = 0.003, p < 0.0001, p < 0.0001, p = 0.0025, and p = 0.04, respectively). The retrospective review underestimated incidences of infection, the need for revision, and deep wound infection (p < 0.0001 for each). Only in the capture of new cardiac events was ICD-9-based reporting more accurate than prospective data accrual (p = 0.04). The most sensitive measure for the appreciation of complication occurrence was the prospective review, followed by the ICD-9-based assessment (p = 0.05). CONCLUSIONS an ICD-9-based coding of perioperative adverse events and major complications in a cohort of spine surgery patients revealed an overall complication incidence similar to that in a prospectively executed measure. In contrast, a retrospective review underestimated complication incidence. The ICD-9-based review captured many medical events of limited clinical import, inflating the overall incidence of adverse events demonstrated by this approach. In multiple categories of major, clinically significant perioperative complications, ICD-9-based and retrospective assessments significantly underestimated complication incidence. These findings illustrate a significant potential weakness and source of inaccuracy in the use of population-based ICD-9 and retrospective complication recording.

Obesity and spine surgery: reassessment based on a prospective evaluation of perioperative complications in elective degenerative thoracolumbar procedures

BACKGROUND CONTEXT The correlation between obesity and incidence of complications in spine surgery is unclear, with some reports suggesting linear relationships between body mass index (BMI) and complication incidence and others noting no relationship. PURPOSE The purpose of this article was to assess the relationship between obesity and occurrence of perioperative complications in an elective thoracolumbar surgery cohort. STUDY DESIGN/SETTING Prospective observational cohort study at a tertiary care facility. PATIENT SAMPLE Cohort of 87 consecutive patients undergoing elective surgery for degenerative thoracolumbar pathologies over a 6-month period (May to December 2008). OUTCOME MEASURES Incidence of perioperative complications (those occurring within 30 days of surgery). METHODS A prospective assessment of perioperative spine surgery complications was completed, and data were prospectively entered into a central database. Two independent auditors assessed for the presence and severity of perioperative complications. Previously validated binary definitions of major and minor complications were used. Patient data and early complications (those occurring within 30 days of index surgery) were analyzed using multivariate regression. RESULTS Mean BMI in this cohort was 31.3; 40.8% of patients were obese (BMI>30) and 10 patients (11.5%) were morbidly obese (BMI>40). The overall complication incidence was 67%. Minor complications occurred in 50% of patients, and major complications occurred in 17.8% of patients. No positioning palsies occurred in this series. Age correlated with an increase in complication risk (p=.006) as did hypertension (p=.004) and performance of a fusion (p<.0001). BMI did not correlate with the incidence of minor, major, or any complications (p=.58). CONCLUSIONS This prospective assessment of perioperative complications in elective degenerative thoracolumbar procedures shows no relationship between patient BMI and the incidence of perioperative minor or major complications. Specific care in perioperative positioning may limit the risk of perioperative positioning palsies in obese patients.

Revision rates and complication incidence in single- and multilevel anterior cervical discectomy and fusion procedures: an administrative database study.

BACKGROUND CONTEXT The natural history of cervical degenerative disease with operative management has not been well described. Even with symptomatic and radiographic evidence of multilevel cervical disease, it is unclear whether single- or multilevel anterior cervical discectomy and fusion (ACDF) procedures produce superior long-term outcomes. PURPOSE To describe national trends in revision rates, complications, and readmission for patients undergoing single and multilevel ACDF. STUDY DESIGN Administrative database study. PATIENT SAMPLE Between 2006 and 2010, 92,867 patients were recorded for ACDF procedures in the Thomson Reuters MarketScan database. Restricting to patients with >24 months follow-up, 28,777 patients fulfilled our inclusion criteria, of which 12,744 (44%) underwent single-level and 16,033 (56%) underwent multilevel ACDFs. OUTCOME MEASURES Revision rates and postoperative complications. METHODS We used the MarketScan database from 2006 to 2010 to select ACDF procedures based on Current Procedural Terminology coding at inpatient visit. Outcome measures were ascertained using either International Classification of Disease version 9 or Current Procedural Terminology coding. RESULTS Perioperative complications were more common in multilevel procedures (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.2-1.6; p<.0001). Single-level ACDF patients had higher rates of postoperative cervical epidural steroid injections (OR, 0.88; 95% CI, 0.8-1.0; p=.01). Within 30 days after index procedure, the multilevel ACDF cohort was 1.6 times more likely to have undergone revision (OR, 1.6; 95% CI, 1.1-2.4; p=.02). At 2 years follow-up, revision rates were 9.13% in the single-level ACDF cohort and 10.7% for multilevel ACDFs (OR, 1.2; 95% CI, 1.1-1.3; p<.0001). In a multivariate analysis at 2 years follow-up, patients from the multilevel cohort were more likely to have received a surgical revision (OR, 1.1; 95% CI, 1.0-1.2; p=.001), to be readmitted into the hospital for any cause (OR, 1.2; 95% CI, 1.1-1.4; p=.007), and to have suffered complications (OR, 1.3; 95% CI, 1.1-1.5; p=.0003). CONCLUSIONS In this study, we report rates of adverse events and the need for revision surgery in patients undergoing single versus multilevel ACDFs. Increasing number of levels fused at the time of index surgery correlated with increased rate of reoperations. Multilevel ACDF patients requiring additional surgery more often underwent more extensive revision surgeries.

The influence of fracture mechanism and morphology on the reliability and validity of two novel thoracolumbar injury classification systems.

Study Design. The Thoracolumbar Injury Severity Score (TLISS) and the Thoracolumbar Injury Classification and Severity Score (TLICS) were prospectively evaluated. Objectives. To compare the reliability and validity of the TLISS and TLICS schemes to determine the importance of injury mechanism and morphology to the identification and treatment of thoracolumbar fractures. Summary of Background Data. Two novel algorithms have been developed for the categorization and management of thoracolumbar injuries: the TLISS system emphasizing injury mechanism and the TLICS scheme involving injury morphology. Methods. The clinical and radiographic findings of 25 patients with thoracolumbar fractures were prospectively presented to 5 groups of surgeons with disparate levels of training and experience with spinal trauma. These injuries were consecutively scored, first using the TLISS and then 3 months later with the TLICS. The recommended treatments proposed by the 2 schemes were compared with the actual management of each patient. Results. For both algorithms, the interrater kappa statistics of all subgroups (mechanism/morphology, status of the posterior ligaments, total score, predicted management) were within the range of moderate to substantial reproducibility (0.45–0.74), and there were no statistically significant differences noted between the respective kappa values. Interrater correlation was higher for the TLISS paradigm on mechanism/morphology, integrity of the posterior ligaments, and proposed management (P ≤ 0.01). The TLISS and TLICS schemes both exhibited excellent overall validity. Conclusions. Although both schemes were noted to have substantial reproducibility and validity, our results indicate the TLISS is more reliable than the TLICS, suggesting that the mechanism of trauma may be a more valuable parameter than fracture morphology for the classification and treatment thoracolumbar injuries. Since these injury characteristics are interrelated and are critical to the maintenance of spinal stability, we think that both concepts should be considered during the assessment and management of these patients.

ASA grade and Charlson Comorbidity Index of spinal surgery patients: correlation with complications and societal costs

BACKGROUND CONTEXT The Charlson Comorbidity Index (CCI) and the American Society of Anesthesiologists (ASA) Physical Status Classification System (ASA grade) are useful for predicting morbidity and mortality for a variety of disease processes. PURPOSE To evaluate CCI and ASA grade as predictors of complications after spinal surgery and examine the correlation between these comorbidity indices and the cost of care. STUDY DESIGN/SETTING Prospective observational study. PATIENT SAMPLE All patients undergoing any spine surgery at a single academic tertiary center over a 6-month period. OUTCOME MEASURES Direct health-care costs estimated from diagnosis related group and Current Procedural Terminology (CPT) codes. METHODS Demographic data, including all patient comorbidities, procedural data, and all complications, occurring within 30 days of the index procedure were prospectively recorded. Charlson Comorbidity Index was calculated from International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes and ASA grades determined from the operative record. Diagnosis related group and CPT codes were captured for each patient. Direct costs were estimated from a societal perspective using Medicare rates of reimbursement. A multivariable analysis was performed to assess the association of the CCI and ASA grade to the rate of complication and direct health-care costs. RESULTS Two hundred twenty-six cases were analyzed. The average CCI score for the patient cohort was 0.92, and the average ASA grade was 2.65. The CCI and ASA grade were significantly correlated, with Spearman ρ of 0.458 (p<.001). Both CCI and ASA grade were associated with increasing body mass index (p<.01) and increasing patient age (p<.0001). Increasing CCI was associated with an increasing likelihood of occurrence of any complication (p=.0093) and of minor complications (p=.0032). Increasing ASA grade was significantly associated with an increasing likelihood of occurrence of a major complication (p=.0035). Increasing ASA grade showed a significant association with increasing direct costs (p=.0062). CONCLUSIONS American Society of Anesthesiologists and CCI scores are useful comorbidity indices for the spine patient population, although neither was completely predictive of complication occurrence. A spine-specific comorbidity index, based on ICD-9-CM coding that could be easily captured from patient records, and which is predictive of patient likelihood of complications and mortality, would be beneficial in patient counseling and choice of operative intervention.

Early Complications Related to Approach in Cervical Spine Surgery: Single-Center Prospective Study

BACKGROUND Surgical intervention is performed on the cervical spine in a heterogeneous number of pathologic conditions in a diverse patient population. Several authors have examined complication prevalence in cervical spine surgery using retrospective analysis. However, few prospective studies have directly examined perioperative complications. Most prospective studies in the spine literature have assessed only specific spinal implants in carefully selected surgical patients, and complication incidence in broader patient populations is limited. OBJECTIVES To prospectively collect data on all patients who underwent cervical spine surgery at a large tertiary care center and to evaluate the effect of the approach and the incidence of early complications. METHODS Data were collected prospectively on 119 patients admitted to the neurosurgical service at Thomas Jefferson University hospital from May to December 2008. Data collected consisted of preoperative diagnosis, medical comorbidities, body mass index, surgical approach, length of stay, and complications, and were analyzed using multivariate regression analysis. Complications occurring within 30 days after each operative procedure were included. Medical adverse events, regardless of their relationship to the operative intervention, were also included as complications. A previously validated binary definition of major and minor complications was used to stratify the data. RESULTS Overall, 53 of 119 patients (44.5%) experienced at least one complication. Eleven of 41 patients (26.8%) undergoing only an anterior cervical procedure had a perioperative complication, compared with 26 of 53 patients (49.0%) undergoing only a posterior cervical procedure (P = .01). In patients undergoing a combined anterior and posterior surgical procedure, 16 of 25 (66%) experienced a complication, a significant difference in comparison with solitary anterior procedures (P = .004). Anterior procedures were associated with postoperative dysphagia and vocal cord paresis, whereas wound infection and C5 palsy was more frequently recorded in the group undergoing surgery via an isolated posterior approach. CONCLUSIONS The incidence of complications or adverse events is not definitely known for most spinal procedures because of the complexity of defining complications and obtaining accurate data. Therefore, to obtain a more accurate assessment of spinal procedures, a prospective algorithm was designed to collect and record complications during the acute perioperative period. Using this technique, a significantly higher complication rate was documented than had been previously reported for cervical spine operative interventions. In addition, use of a broad definition of perioperative complications likely increased the recorded incidence of perioperative adverse events and complications. Complications were more common in patients undergoing posterior and anteroposterior procedures.

Geographic variation and regional trends in adoption of endovascular techniques for cerebral aneurysms

OBJECT Considerable evolution has occurred in treatment options for cerebral aneurysms. Development of endovascular techniques has produced a significant change in the treatment of ruptured and unruptured intracranial aneurysms. Adoption of endovascular techniques and increasing numbers of patients undergoing endovascular treatment may affect health care expenditures. Geographic assessment of growth in endovascular procedures has not been assessed. METHODS The National Inpatient Sample (NIS) was queried for ICD-9 codes for clipping and coiling of ruptured and unruptured cerebral aneurysms from 2002 to 2008. Patients with ruptured and unruptured cerebral aneurysms were compared according to in-hospital deaths, hospital length of stay, total hospital cost, and selected procedure. Hospital costs were adjusted to bring all costs to 2008 equivalents. Regional variation over the course of the study was explored. RESULTS The NIS recorded 12,588 ruptured cerebral aneurysm cases (7318 clipped and 5270 coiled aneurysms) compared with 11,606 unruptured aneurysm cases (5216 clipped and 6390 coiled aneurysms), representing approximately 121,000 aneurysms treated in the study period. Linear regression analysis found that the number of patients treated endovascularly increased over time, with the total number of endovascular patients increasing from 17.28% to 57.59% for ruptured aneurysms and from 29.70% to 62.73% for unruptured aneurysms (p < 0.00001). Patient age, elective status, and comorbidities increased the likelihood of endovascular treatment (p < 0.00001, p < 0.00004, and p < 0.02, respectively). In patients presenting with subarachnoid hemorrhage (SAH), endovascular treatments were more commonly chosen in urban and academic medical centers (p = 0.009 and p = 0.05, respectively). In-hospital deaths decreased over the study period in patients with both ruptured and unruptured aneurysms (p < 0.00001); presentation with SAH remained the single greatest predictor of death (OR 38.09, p < 0.00001). Geographic analysis showed growth in endovascular techniques concentrated in eastern and western coastal states, with substantial variation in adoption of endovascular techniques (range of percentage of endovascular patients [2008] 0%-92%). There were higher costs in patients treated endovascularly, but these differences were likely secondary to presenting diagnosis and site-of-service variations. CONCLUSIONS The NIS database reveals a significant increase in the use of endovascular techniques, with the majority of both ruptured and unruptured aneurysms treated endovascularly by 2008. Differences in hospital costs between open and endovascular techniques are likely secondary to patient and site-of-service factors. Presentation with SAH was the primary factor affecting hospital cost and a greater percentage of endovascular procedures completed at urban academic medical centers. There is substantial regional variation in the adoption of endovascular techniques.

Osteochondroma of the C5 lamina with cord compression: case report and review of the literature.

STUDY DESIGN Case report of a solitary osteochondroma of the cervical spine causing myelopathy in a 66-year-old woman. OBJECTIVES To review the relevant literature and describe a highly unusual clinical manifestation of solitary osteochondroma. SUMMARY OF BACKGROUND DATA Osteochondromas are common benign bony lesions that seldom occur in the axial skeleton. These lesions are more commonly reported with neural compression in cases of hereditary multiple exostoses (Bessel-Hagel syndrome, diaphyseal aclasis). METHODS Chart review, review of relevant radiographic examinations and histopathologic specimens, clinical follow-up with examination, and literature review. RESULTS Manifestation with new neurologic deficit in a 66-year-old patient was singular. CONCLUSIONS Osteochondromas are unusual in the axial skeleton, and are rarely signaled by neural compression. Occurrence is generally in young adults in the second and third decades. Initial manifestation with a new neurologic deficit in a 66-year-old patient was highly unusual.

High-resolution ultrasonography in the diagnosis and intraoperative management of peripheral nerve lesions

OBJECT The diagnosis of peripheral nerve lesions relies on clinical history, physical examination, electrodiagnostic studies, and radiography. Magnetic resonance neurography offers high-resolution visualization of structural peripheral nerve lesions. The availability of MR neurography may be limited, and the costs can be significant. By comparison, ultrasonography is a portable, dynamic, and economic technology. The authors explored the clinical applicability of high-resolution ultrasonography in the preoperative and intraoperative management of peripheral nerve lesions. METHODS The authors completed a retrospective analysis of 13 patients undergoing ultrasonographic evaluation and surgical treatment of nerve lesions at their institution (nerve entrapment [5], trauma [6], and tumor [2]). Ultrasonography was used for diagnostic (12 of 13 cases) and intraoperative management (6 of 13 cases). The authors examine the initial impact of ultrasonography on clinical management. RESULTS Ultrasonography was an effective imaging modality that augmented electrophysiological and other neuroimaging studies. The modality provided immediate visualization of a sutured peroneal nerve after a basal cell excision, prompting urgent surgical exploration. Ultrasonography was used intraoperatively in 2 cases to identify postoperative neuromas after mastectomy, facilitating focused excision. Ultrasonography correctly diagnosed an inflamed lymph node in a patient in whom MR imaging studies had detected a schwannoma, and the modality correctly diagnosed a tendinopathy in another patient referred for ulnar neuropathy. Ultrasonography was used in 6 patients to guide the surgical approach and to aid in intraoperative localization; it was invaluable in localizing the proximal segment of a radial nerve sectioned by a humerus fracture. In all cases, ultrasonography demonstrated the correct lesion diagnosis and location (100%); in 7 (58%) of 12 cases, ultrasonography provided the correct diagnosis when other imaging and electrophysiological studies were inconclusive or inadequate. CONCLUSIONS High-resolution ultrasonography may provide an economical and accurate imaging modality with utility in diagnosis and management of peripheral nerve lesions. Further research is required to assess the role of ultrasonography in evaluation of peripheral nerve pathology.