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.

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.

Postoperative prevertebral soft tissue swelling does not affect the development of chronic dysphagia following anterior cervical spine surgery.

STUDY DESIGN: Prospective cohort study. OBJECTIVE: To characterize the relation between postoperative soft tissue swelling and the development of chronic dysphagia after anterior cervical spine surgery. Chronic dysphagia was defined as dysphagia that persists more than 1 year. SUMMARY OF BACKGROUND DATA: Dysphagia is commonly reported in the early postoperative period after anterior cervical spine surgery. Although prevertebral soft tissue swelling (STS) has been hypothesized as a potential risk factor for development of dysphagia, no studies have assessed STS' relation to dysphagia that persists more than 1 year. METHODS: Sixty-seven patients who underwent elective anterior cervical spine surgery from 2008 to 2011 and completed a dysphagia questionnaire were included in the study. Prevertebral STS was measured at the caudal endplates of C2 and C6 on plain lateral cervical radiographs preoperatively, immediately after, and 6 and 12 weeks postoperatively. The presence and severity of chronic dysphagia was assessed using the Bazaz-Yoo Dysphagia Score. The prevalence of dysphagia in relation to STS was evaluated using the Wilcoxon rank-sum test. RESULTS: By 6 weeks after surgery, 89% of STS at C2 and 97% of STS at C6 had resolved, as compared with preoperative values. The overall dysphagia prevalence in our cohort was 73%, with 48% reporting no or mild symptoms. Moderate symptoms were present in 39% and severe symptoms were present in 13% of the patients. There was no relation between STS measured at all time points compared with the development of chronic dysphagia. Dysphagia did trend toward significance with higher cervical fusions (C4 and above) and as the number of levels fused increased, but STS did not seem to influence this. CONCLUSION: Postoperative STS is a self-limiting process. The magnitude of STS during the postoperative period does not seem to influence the development of chronic dysphagia.

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, χ 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.

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.

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.

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 CHARITE 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.

Bioabsorbable fixation in foot and ankle.

Bioabsorbable implants are playing an increasing role in the surgical management of foot and ankle pathologies. Current technology allows implants to have acceptably comparable strength and pull-out characteristics to metallic implants. The advantages include elimination of secondary surgeries, biodegradability of implants placed across mobile articular surfaces, as well as acceptable biocompatibility and resorption properties to limit historical complication concerns.