Alexander C. Ching

Adverse events associated with anterior cervical spine surgery.

&NA; Anterior cervical procedures for neurologic decompression and fusion, including cervical diskectomy and cervical corpectomy, are commonly performed by orthopaedic surgeons and spinal neurosurgeons. These procedures are highly successful in treating most patients with persistent pain and neurologic symptoms that have not responded to nonsurgical methods. Adverse events occur infrequently, but several have been described, including esophageal injury, vertebral artery injury, dural tear, postoperative airway compromise, spinal cord injury, hematoma, dysphagia, dysphonia, and graft dislodgement. Newer procedures, such as cervical total disk replacement and the use of bone morphogenetic protein as a supplement to fusion, have raised unique concerns. Appropriate strategies must be utilized to avoid these adverse events, and the treating surgeon should have an understanding of how to detect and manage such events when they do arise.

Relationship between preoperative expectations, satisfaction, and functional outcomes in patients undergoing lumbar and cervical spine surgery: A multicenter study

Study Design. Analysis of prospectively collected multicenter data. Objective. To explore the relationship between preoperative expectations and postoperative outcomes and satisfaction in lumbar and cervical spine surgery. Summary of Background Data. Back pain is one of the most common health problems, leading to the utilization of health care resources, work loss, and sick benefits. Patient expectations influence posttreatment outcomes, both surgical and nonsurgical. There is little research on the importance of preoperative expectations in spine surgery. Existing studies evaluate the technical aspects of interventions and functional outcomes but fail to take into account patient expectations. The authors hypothesized that expectations dramatically affect spine patient satisfaction independent of functional outcomes. Methods. Prospectively collected patient-entered data from patients undergoing lumbar and cervical spine surgery from 2 study centers collected using a Web-based patient health survey system were analyzed. The study included patients who underwent operative intervention (decompression with or without fusion) with at least a 3-month period of follow-up. Preoperative expectations were measured using the Musculoskeletal Outcomes Data Evaluation and Management Systems (MODEMS) expectation survey. Postoperative satisfaction and fulfillment of expectations were measured using the MODEMS satisfaction survey. Postoperative functional outcomes were measured using the Oswestry Disability Index and 36-item short form health survey. Ordinal logistic regression multivariate modeling was used to examine predictors of postoperative satisfaction. Linear regression multivariate modeling was used to examine predictors of functional outcomes. Results. Greater fulfillment of expectations led to higher postoperative satisfaction and was associated with better functional outcomes. Higher preoperative expectations led to decreased postsurgical satisfaction but were associated with improved functional outcomes. Higher postoperative satisfaction was associated with improved functional outcomes and vice versa. Type of surgery also influenced satisfaction and function, with cervical patients being less satisfied but having better functional outcomes than lumbar patients. Conclusion. This study showed that more than functional outcomes matter; preoperative expectations and fulfillment of expectations influence postoperative satisfaction in patients undergoing lumbar and cervical spine surgery. This underlines the importance of taking preoperative expectations into account to obtain an informed choice on the basis of the patients preferences.

Posterior fixation without debridement for vertebral body osteomyelitis and discitis

OBJECT The authors evaluated the efficacy of posterior instrumentation for the management of spontaneous spinal infections. Standard surgical management of spontaneous spinal infection is based on debridement of the infected tissue. However, this can be very challenging as most of these patients are medically debilitated and the surgical debridement requires a more aggressive approach to the spine either anteriorly or via an expanded posterior approach. The authors present their results using an alternative treatment method of posterior-only neuro-decompression and stabilization without formal debridement of anterior tissue for treating spontaneous spinal infection. METHODS Fifteen consecutive patients were treated surgically by 2 of the authors. All patients had osteomyelitis and discitis and were treated postoperatively with intravenous antibiotics for at least 6 weeks. The indications for surgery were failed medical management, progressive deformity with ongoing persistent spinal infection, or neurological deficit. Patients with simple epidural abscess without bony instability were treated with laminectomy and were not included in this series. Fourteen patients were treated with posterior-only decompression and long-segment rigid fixation, without formal debridement of the infected area. One patient was treated with staged anterior and posterior surgery due to delay in treatment related to medical comorbidities. The authors examined as their outcome the ambulatory status and recurrence of deep infection requiring additional surgery or medical treatment. RESULTS Of the initial 15 patients, 10 (66%) had a minimum 2-year follow-up and 14 patients had at least 1 year of followup. There were no recurrent spinal infections. There were 3 unplanned reoperations (1 for loss of fixation, 1 for early superficial wound infection, and 1 for epidural hematoma). Nine (60%) of 15 patients were nonambulatory at presentation. At final followup, 8 of 15 patients were independently ambulatory, 6 required an assistive device, and 1 remained nonambulatory. CONCLUSIONS Long-segment fixation, without formal debridement, resulted in resolution of spinal infection in all cases and in significant neurological recovery in almost all cases. This surgical technique, when combined with aggressive antibiotic therapy and a multidisciplinary team approach, is an effective way of managing serious spinal infections in a challenging patient population.

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.

Short segment coronal plane deformity after two-level lumbar total disc replacement.

Study Design. Case series of 2-level lumbar disc arthroplasties treated by the authors. Objective. Identify a potentially significant failure rate of 2-level disc arthroplasty due to coronal plane instability. Summary of Background Data. Arthrodesis remains the standard for surgical treatment of degenerative disc disease, despite concerns about adjacent level degeneration and persistent postoperative pain in some patients. Total disc arthroplasty has been proposed as a way to reduce these problems. Intermediate follow-up of 1-level procedures demonstrates promising safety and improved pain scores. Some surgeons are expanding the surgical indications to more challenging settings, including multilevel disease. Methods. We report here our experience with 4 cases of failed 2-level disc arthroplasty. Results. We have seen 4 patients with failed 2-level lumbar arthroplasty, of those 2 performed in Germany and 2 performed in our state by 2 different experienced spine surgeons. The 2 local cases represent 29% (2/7) of all 2-level CHARITÉ arthroplasties performed within our state. All 4 patients presented within 11 to 13 months of implantation with increased back pain and radicular symptoms. The mechanism of failure was coronal instability due to small deviations of the prostheses from a midline position in all 4 cases. Conclusion. Disc arthroplasty appears to be a safe and effective treatment for 1-level lumbar degenerative disc disease. Although promising biomechanical reports of 2-level models are emerging, we are concerned by the rate of failures of 2-level arthroplasty that we are seeing. It appears that the potential for coronal plane instability increases as the number of levels increases. Given the costs and risks associated with these procedures, we feel that this issue deserves the attention of the spine surgery community despite the limited numbers in this report.

Predictors and prevalence of patients undergoing additional kyphoplasty procedures after an initial kyphoplasty procedure

BACKGROUND CONTEXT Vertebral cement augmentation, including kyphoplasty, has been shown to be a successful treatment for pain relief for vertebral compression fracture (VCF). Patients can sustain additional symptomatic VCFs that may require additional surgical intervention. PURPOSE To examine the prevalence and predictors of patients who sustain additional symptomatic VCFs that were treated with kyphoplasty. STUDY DESIGN A retrospective review of patients who previously underwent kyphoplasty for VCFs and had additional VCFs that were treated with kyphoplasty. PATIENT SAMPLE A total of 256 patients underwent kyphoplasty for VCFs from 2000 to 2007 at a single medical center. OUTCOME MEASURES The outcome measure of interest was the need for an additional kyphoplasty procedure for a symptomatic VCF. METHODS Risk factors such as age, sex, smoking status, and steroid use were assessed, as well as bisphosphonate use. Sagittal spinal alignment via Cobb angles for thoracic, thoracolumbar, and lumbar regions was assessed. RESULTS About 22.2% of the patients had an additional symptomatic VCF that was treated with a kyphoplasty procedure. Steroid use was the only significant risk factor for predicting patients with additional symptomatic VCFs who underwent additional kyphoplasty. The average time to the second VCF was 33 days. Adjacent-level VCFs were most common in the thoracic and thoracolumbar spine. Bisphosphonate use was not shown to be protective of preventing additional VCFs during this follow-up period. CONCLUSION This is the first single-center review of a large cohort of patients who underwent additional-level kyphoplasty for symptomatic VCFs after an index kyphoplasty procedure. Our results suggest that patients with a VCF who use chronic oral steroids should be carefully monitored for the presence of additional symptomatic VCFs that may need surgical intervention. Patients with prior thoracic VCFs who have additional back pain should be reevaluated for a possible adjacent-level fracture.

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.

How do we interpret national inpatient sample data about complications? Commentary on an article by Amit Jain, MD, et al.: "rhBMP Use in Cervical Spine Surgery: Associated Factors and In-hospital Complications".

Achieving solid osseous fusion remains a challenge in spine surgery. Autologous iliac crest bone graft remains the gold-standard graft material. In most cases, the fusion rates achievable with modern surgical techniques and autologous iliac crest bone graft are >90%. In specific scenarios, including long-segment fusion surgery and in patients with comorbidities, the fusion rates are substantially lower than this benchmark. Commercially available recombinant human bone morphogenetic protein (rhBMP) has rapidly been adopted as an alternative that can avoid the morbidity of iliac crest harvest and yet achieve similar, or possibly better, fusion rates than autograft bone. A number of recent publications have questioned the potential risks associated with the use of rhBMP1. A series of papers showing conflicting results has followed: some describing serious complications associated with rhBMP, and some reporting minimal or no effect on complication rates. In fact, two independent groups analyzed individual patient-level data supplied by the manufacturer of rhBMP-2 (Medtronic Sofamor Danek) and reached similar, but not identical, conclusions2,3. This controversy is the context for the paper by Jain et al., which describes the use of rhBMP in cervical spine surgery …

How Do We Interpret National Inpatient Sample Data About Complications

Achieving solid osseous fusion remains a challenge in spine surgery. Autologous iliac crest bone graft remains the gold-standard graft material. In most cases, the fusion rates achievable with modern surgical techniques and autologous iliac crest bone graft are >90%. In specific scenarios, including long-segment fusion surgery and in patients with comorbidities, the fusion rates are substantially lower than this benchmark. Commercially available recombinant human bone morphogenetic protein (rhBMP) has rapidly been adopted as an alternative that can avoid the morbidity of iliac crest harvest and yet achieve similar, or possibly better, fusion rates than autograft bone. A number of recent publications have questioned the potential risks associated with the use of rhBMP1. A series of papers showing conflicting results has followed: some describing serious complications associated with rhBMP, and some reporting minimal or no effect on complication rates. In fact, two independent groups analyzed individual patient-level data supplied by the manufacturer of rhBMP-2 (Medtronic Sofamor Danek) and reached similar, but not identical, conclusions2,3. This controversy is the context for the paper by Jain et al., which describes the use of rhBMP in cervical spine surgery …

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