Natalie L. Zusman

Incidence of second cervical vertebral fractures far surpassed the rate predicted by the changing age distribution and growth among elderly persons in the United States (2005-2008).

Study Design. Nationwide epidemiological cohort study. Objective. To characterize the incidence of second cervical vertebral (C2) fractures by age and geographical region among the elderly Medicare population and to elucidate if the rate changed in the years 2005 to 2008. Summary of Background Data. Recent publications hypothesized that the rate of cervical vertebral fractures may be increasing. To date, there are no published nationwide reports describing the incidence and demographics of these injuries in the elderly US population. Methods. Incidence of C2 fracture in the years 2005 to 2008 was determined by querying PearlDiver Technologies, Inc. (Warsaw, IN), a commercially available database, using International Classification of Diseases code 805.02. Rates were calculated using the PearlDiver reported person-counts as the numerator and the Center for Medicare and Medicare Services midyear population file as the denominator, and reported per 10,000 person-years (10,000 p-y). The age and geographical distributions of fractures were examined. Variability in rates was analyzed using the mean, standard deviation, 95% confidence intervals, &khgr;2 tests, and Pearson correlation coefficients. Results. Although the elderly population increased by 6% between 2005 and 2008, the annual incidence of C2 fracture rose by 21%, from 1.58 to 1.91 per 10,000 p-y, trending upward in a straight-line function (r = 0.999, P = 0.0006). The incidence of fracture varied between age groups; however, an increase was observed in all age groups. Persons aged 65 to 74 years (the youngest age group) experienced the lowest incidence (0.63 in 2005 to 0.71 in 2008), and the rate of increase was the smallest among the age groups examined (13%). Persons aged 85 and older demonstrated the highest incidence (4.36–5.67) and the greatest increase (30%). Conclusion. From 2005 to 2008, the overall incidence of C2 fracture rose at a rate that was 3.5 times faster than the elderly population growth.

A scoring system to predict postoperative medical complications in high-risk patients undergoing elective thoracic and lumbar arthrodesis.

BACKGROUND CONTEXT Various surgical factors affect the incidence of postoperative medical complications following elective spinal arthrodesis. Because of the inter-relatedness of these factors, it is difficult for clinicians to accurately risk-stratify individual patients. PURPOSE Our goal was to develop a scoring system that predicts the rate of major medical complications in patients with significant preoperative medical comorbidities, as a function of the four perioperative parameters that are most closely associated with the invasiveness of the surgical intervention. STUDY DESIGN/SETTING This study used level 2, Prognostic Retrospective Study. PATIENT SAMPLE The patient sample consisted of 281 patients with American Society of Anesthesiologists (ASA) scores of 3-4 who underwent elective thoracic, lumbar, or thoracolumbar fusion surgeries from 2007 to 2011. OUTCOME MEASURES Physiologic risk factors, number of levels fused, complications, operative time, intraoperative fluids, and estimate blood loss were the outcome measures of this study. METHODS Risk factors were recorded, and patients who suffered major medical complications within the 30-day postoperative period were identified. We used chi-square tests to identify factors that affect the medical complication rate. These factors were ranked and scored by quartiles. The quartile scores were combined to form a single composite score. We determined the major medical complication rate for each composite score, and divided the cohort into quartiles again based on score. A Pearson linear regression analysis was used to compare the incidence of complications to the score. RESULTS The number of fused levels, operative time, volume of intraoperative fluids, and estimated blood loss influenced the complication rate of patients with ASA scores of 3-4. The quartile ranking of each of the four predictive factors was added, and the sum became the composite score. This score predicted the complication rate in a linear fashion ranging from 7.6% for the lowest risk group to 34.7% for the highest group (r=0.998, p<.001). CONCLUSIONS Taken together, the four factors, though not independent of one another, proved to be strongly predictive of the major medical complication rate. This score can be used to guide medical management of thoracic and lumbar spinal arthrodesis patients with preexisting medical comorbidities.

Association between advanced degenerative changes of the atlanto-dens joint and presence of dens fracture.

BACKGROUND Dens fractures in elderly patients are often related to issues associated with aging. We examined the association between degenerative changes of the atlanto-dens joint and the risk of dens fracture. METHODS We conducted a retrospective study of trauma patients, fifty-five years of age or older, who had undergone a computed tomography scan of the cervical spine as part of their admission to a single level-I trauma center. There were 1794 patients who met the inclusion criteria; scans were evaluated for all fifty-six who presented with a dens fracture and for a random sample of 736 without a dens fracture. Intraosseous cyst formation, synovitis, and joint space narrowing were recorded from the scans. The prevalence of degenerative changes was compared between patients with and patients without a dens fracture. RESULTS An intraosseous cyst in the dens was found in 16.4% of the patients without a dens fracture and in 64.3% of those with a fracture (p < 0.001). The dens fracture extended through the existing cyst in twenty-four (66.7%) of thirty-six patients with a cyst and a dens fracture. Retro-dens synovitis was present in 4.2% of the patients without a dens fracture and 25.0% of those with a fracture (p < 0.001). After adjustment for age and sex, both cysts (odds ratio [OR] = 7.7, 95% confidence interval [CI] = 4.2 to 14.1) and synovitis (OR = 4.6, 95% CI = 2.1 to 10.0) were significantly associated with dens fracture. CONCLUSIONS Intraosseous dens cysts and retro-dens synovitis were associated with dens fracture; those with a dens fracture were nearly eightfold more likely to have an intraosseous cyst and nearly fivefold more likely to have synovitis compared with those without a dens fracture. Because the atlanto-dens joint is a synovial joint, its degeneration can lead to subchondral cyst formation and synovitis and predispose affected individuals to fracture.

Life Expectancy and Metastatic Spine Scoring Systems: An Academic Institutional Experience

Study Design: A retrospective data collection study with application of metastatic spine scoring systems. Objectives: To apply the Tomita and revised Tokuhashi scoring systems to a surgical cohort at a single academic institution and analyze spine-related surgical morbidity and mortality rates. Summary of Background Data: Surgical management of metastatic spine patients requires tools that can accurately predict patient survival, as well as knowledge of morbidity and mortality rates. Methods: An Oregon Health & Science University (OHSU) Spine Center surgical database was queried (years 2002–2010) to identify patients with an ICD-9 code indicative of metastatic spine disease. Patients whose only surgical treatment was vertebral augmentation were not included. Scatter plots of survival versus the Tomita and revised Tokuhashi metastatic spine scoring systems were statistically analyzed. Spine-related morbidity and mortality rates were calculated. Results: Sixty-eight patients were identified: 45 patients’ (30 male patients, mean age 45 y) medical records included operative, morbidity, and mortality statistic data and 38 (26 male patients, mean age 54 y) contained complete metastatic spine scoring system data. Of the 38 deceased spine metastatic patients, 8 had renal cell, 7 lung, 4 breast, 2 chondrosarcoma, 2 prostate, 11 other, and 4 unknown primary cancers. Linear regression analysis revealed R2 values of 0.2570 and 0.2009 for the revised Tokuhashi and Tomita scoring systems, respectively. Overall transfusion, infection, morbidity, and mortality rates were 33% and 9%, and 42% and 9%, respectively. Conclusions: Application of metastatic prognostic scoring systems to a retrospective surgical cohort revealed an overall poor correlation with the Tomita and revised Tokuhashi predictive survival models. Morbidity and mortality rates concur with those in the medical literature. This study underscores the difficulty in utilizing metastatic spine scoring systems to predict patient survival. We believe a scoring system based on cancer type is needed to account for changes in treatment paradigms with improved patient survival over time.

Traditional threshold for retropharyngeal soft-tissue swelling is poorly sensitive for the detection of cervical spine injury on computed tomography in adult trauma patients.

Study Design. Retrospective cohort study. Objective. To examine the diagnostic value of prevertebral soft-tissue swelling in the setting of cervical spine trauma. Summary of Background Data. In adult patients with trauma, an increase in the thickness of the retropharyngeal soft tissues is commonly used as a potential indicator of occult injury, but no studies have examined this parameter using computed tomography (CT) as a screening modality. Methods. A total of 541 patients with trauma with injuries at any level of the spine underwent CT. Patients with cervical injury were divided into those requiring noninvasive (observation or cervical collar, n = 142) management, and those requiring invasive (surgery or halo, n = 61) treatment. A control group of patients with isolated thoracic or lumbar injuries was used for comparison (n = 542). Retropharyngeal soft tissues were measured at the cranial and caudal endplates of all cervical levels on sagittal and axial CT. Sensitivity and specificity were calculated for +1, +2, and +3 standard deviations from mean values. Results. Sensitivity for detection of injury was found to be universally poor for all measurement groups. This ranged from 14.4% to 21.2% at +1 SD to 5.3% to 8.7% at +2 SD. Positive and negative predictive values for injury were also universally poor, ranging from 38% to 75%. Soft-tissue swelling as a sentinel sign of cervical spine injury demonstrates consistently high specificity and low sensitivity, precisely the opposite of what would be desired in a screening test. This study shows at best a sensitivity of 21.6% when using this parameter for the detection of these injuries in adult patients with trauma. Conclusion. On the basis of the results of this study, we recommend against the routine use of measurement of the prevertebral soft tissues on CT as a screening tool for cervical spine injury in adult patients with trauma. Level of Evidence: 3