In the second of three Best Paper sessions scheduled at NASS 2017, investigators will present seven of this year’s highest rated abstracts, including studies exploring surgical and nonsurgical approaches for lumbar spinal stenosis, indications and efficacy of lumbar epidural steroid injections and the relationship between preoperative opioid use and length of hospital stay in adult spinal deformity patients.
The Scientific Program Committee received more than 1,000 abstract and session proposal submissions for this year’s Annual Meeting in Orlando. From those accepted, the 21 highest rated abstracts will be presented during three separate Best Paper sessions on Wednesday, Thursday and Friday at NASS 2017.
Following are previews of the Best Papers that will be presented on Thursday, October 26. Look for previews of the Best Paper presentations scheduled for Friday at the meeting in the September e-preview edition of the NASS Daily News. Visit the July e-preview for previews of the Best Papers scheduled for Wednesday, October 25.
BEST PAPERS: THURSDAY, OCTOBER 26, 2017
A Comparison of Nonsurgical Treatment Methods for Patients with Lumbar Spinal Stenosis
Presenting author: Michael J. Schneider, DC, PhD
Lumbar spinal stenosis (LSS) is the most common reason for spine surgery in older adults. For patients who are not surgical candidates, however, there is very little research evidence regarding the effectiveness of various nonsurgical treatment options.
In this randomized controlled trial, investigators compared the effectiveness of three common nonsurgical approaches for 260 patients diagnosed with LSS: medical care by a physiatrist with oral medications and/or epidural injection; group (nonspecific) exercise classes at community centers; and manual therapy and specific exercise by chiropractors and physical therapists.
“Outcome measures were the Swiss Spinal Stenosis (SSS) score, self-paced walking test (SPWT) and daily physical activity (PA),” said Michael J. Schneider, DC, PhD. “Treatment responders were defined as patients who showed at least a 30% improvement in any of these outcomes, which were measured at baseline, two months and six months.”
Results indicated that patients in all three groups showed modest reduction in symptom severity (SSS), but more robust improvement in walking distance (SPWT). The manual therapy group had a significantly greater proportion of SSS and SPWT responders at two months compared to the other two groups. All three groups maintained their respective improvements at six months, although there were no longer any significant between-group differences.
“The average level of daily physical activity did not show much improvement from baseline at either two or six months, although about 20% of patients in all three groups were PA responders at both time points,” Dr. Schneider said. “This study provides evidence for the safety and effectiveness of three non-surgical treatment options for LSS patients who are not surgical candidates.”
Boot Camp Programs for Lumbar Spinal Stenosis: A Randomized Controlled Trial Comparing Outcomes Following a Comprehensive vs Self-Directed Nonsurgical Approach
Presenting author: Carlo Ammendolia, DC, PhD
Lumbar spinal stenosis (LSS) is a leading cause of pain, disability and loss of independence in older adults. With the aging population, we are experiencing an exponential rise in the number of people suffering from LSS. The vast majority of people with LSS receive nonsurgical care; however, the effectiveness of nonsurgical care for LSS is unknown.
“In this study, we set out to compare the effectiveness of a six-week structured comprehensive conservative training program that included education, manual therapy, home based exercises and instruction on self-management strategies with a self-directed training program that included an educational workbook, video and pedometer,” said Carlo Ammendolia, DC, PhD. “We selected objective walking distance as our primary outcome because walking ability is the dominant functional limitation in this population.”
The researchers found that both groups showed significant improvement in walking ability, with the comprehensive group demonstrating statistically and clinically superior improvement at eight weeks, three-, six- and 12-month follow-up. Excellent improvements were also seen in physical function and bodily pain at 12 months.
“Not only did the comprehensive group demonstrate a large improvement in walking distance at eight weeks — a mean increase of 501 meters in a 30-minute walk test — but the benefits were sustained at 12 months — a mean increase in walking distance in 30 minutes of 675 meters — even after the termination of the intervention at 10 weeks post randomization,” Dr. Ammendolia said.
Estimating Quality Adjusted Life Years Using the Patient Reported Outcomes Measurement Information System (PROMIS) Health Domains
Presenting author: Richard L. Skolasky, ScD
As clinicians and researchers become more familiar with the Patient Reported Outcomes Measurement Information System (PROMIS) and incorporate assessment of PROMIS health domains into their clinical practices and research trials, it is critical to understand how to use the new information to estimate health utility (a rating scale to assess general health and health-related quality of life).
“In our study, we developed and validated an algorithm to estimate health utility using the PROMIS health domains that were identified as important by spine patients — pain, physical function, fatigue, anxiety, depression, sleep disturbance and satisfaction with participation in social roles,” said Richard L. Skolasky, ScD.
The study utilized data prospectively collected on 424 patients with cervical and/or lumbar spine disease who were randomly allocated to a derivation cohort and a validation cohort in a 1:1 fashion. In the derivation sample, quality-adjusted life years (QALYs) were estimated, using linear regression, as a function of PROMIS health domains. Model fit statistics were used to determine the most parsimonious QALY estimation equation. In the validation sample, QALYs were calculated using the QALY estimation equation. QALYs based on the PROMIS health domains were correlated with QALYs derived from the Medical Outcomes Study Short Form 12, version 2 (SF12v2). Sensitivity analyses were also conducted.
“Our results demonstrate that our final QALY estimating equation can be used by clinicians and health researchers to estimate the impact that medical care or other intervention has on a patient’s quality of life — a key component of measuring the value of health care,” Dr. Skolasky said.
Lumbar Epidural Steroid Injections: Incidence and Determinants of Subsequent Surgery
Presenting author: Jayme Koltsov, PhD
Lumbosacral epidural steroid injection (ESI) use has increased dramatically; however, the indications for use and efficacy remain unclear. Previously reported success rates range from 18% to 90%, depending on the methodology, patient selection, techniques and outcome measures used. A major goal of ESIs is to avoid or delay surgery, yet little information exists regarding what proportion of ESI patients progress to surgery and the typical time frame within which this occurs.
“Therefore, the goal of our research is to determine what proportion of patients receiving ESI subsequently undergo lumbar surgery, the typical timing of this progression, and the factors that are associated with subsequent surgery,” said Jayme Koltsov, PhD.
In a retrospective review of a large national administrative claims database, the investigators found that, within one year of lumbar ESI for a diagnosis of stenosis and/or herniation, 25% of patients underwent lumbar surgery and 34% required a second injection. After risk-adjustment, the rate of surgery after ESI for herniation was 2.4 times that for stenosis.
Younger age, concomitant spine diagnoses, previous treatment for tobacco use, and patient residence in a rural location were associated with increased risk for subsequent surgery. Conversely, female sex, comorbidities — including cardiopulmonary and neurologic comorbidities, obesity, diabetes, chronic pain, anxiety and previous treatment for drug use — were associated with lower risk for subsequent surgery.
“Although one-fourth of lumbar ESI patients required surgery within one year, it is unknown how many of these patients initially would have been surgical candidates,” Dr. Koltsov said. “Additional study, including symptom severity and the extent of neural compression, will shed further light on the effectiveness of ESI for delaying or preventing surgery.”
Cost-Effectiveness of Operative vs Nonoperative treatment of Adult Lumbar Scoliosis
Presenting author: Leah Y. Carreon, MD, MSc
Uncertainty continues regarding the cost-effectiveness of treatments for adult symptomatic lumbar scoliosis (ASLS). Nonoperative care provides little health-related quality of life (HRQOL) benefit, although these patients may have worsened without treatment. Surgery improves HRQOL, but is costly with high revision rates. This study explores this issue via a cost-effectiveness analysis using data from an NIH-sponsored trial.
Patients undergoing operative or nonsurgical treatment (as treated) with at least two-year follow-up within the specific treatment arm were included. Surgical costs for the index and revision surgeries within two years were determined using Medicare allowable rates. Data collected every three months included utilization of nonoperative resources (physical therapy, chiropractor, pain management, steroid injection), medication use (NSAIDs, opioids, muscle relaxants) and employment status.
Direct costs were determined using Medicare allowable rates. Medication costs were determined using the Red Book and indirect costs were determined based on reported employment status and income. Quality-adjusted life years (QALYs) were calculated by two methodologies, deriving Short-Form Six-Dimension (SF6D) values from both the Oswestry Disability Index (ODI) and Short Form Health Survey (SF-12).
Based on their findings, the researchers report that cost-effectiveness of operative and nonoperative treatment of lumbar scoliosis is similar at two years. Depending on the QALY valuation methodology used, the incremental cost effectiveness ratio (ICER) may favor either surgical or nonsurgical treatment. Neither treatment reaches the commonly cited threshold of $100,000/QALY. Longer followup is needed to determine if the ICER for surgical treatment will improve based on durability of clinical benefit or deteriorate due to additional costs associated with revision surgery.
Preoperative Opioid Use is an Independent Predictor of a Prolonged Length of Hospital Stay (LOS) following Adult Spine Deformity Surgery: A Multicenter Study of 819 Patients
Presenting author: Micheal Raad, MD
The efforts to improve pain treatment awareness among physicians in the late 1980s culminated in soaring opioid prescriptions over the next decades. Today, both medical and recreational opioid are dubbed “epidemic.” Although effective at pain relief, opioid use is known to be associated with substantial side effects and the very well known risks of dependence and overdose. Additionally, opioid use has been shown to significantly increase costs and complications while negatively affecting outcomes in surgical patients.
“Given the high levels of pain, adult spinal deformity patients have relatively high rates of opioid consumption; however, no previously published reports have attempted to investigate the effects of preoperative opioid use on postoperative outcomes in this patient population,” said Micheal Raad, MD. “The aim of our study is to describe and investigate opioid use in these patients and determine its effects on the postoperative course.”
The investigators looked at 819 patients who underwent surgery for adult spinal deformity. They found that patients who reported heavy opioid use preoperatively were at a significantly higher risk of requiring a prolonged length of intensive care unit stay and total length of hospital stay. They also looked at a robust set of potential confounders — including levels of pain, demographics, radiographic deformity and surgical invasiveness — and found the correlation between opioid use and postoperative outcomes was still present after controlling for all potential confounders.
“Our results suggest that physicians should consider a patient’s use of opioids preoperatively as a risk factor for a longer hospital course,” Dr. Raad said. “We believe that understanding and highlighting this relationship will help in patient risk stratification, optimizing health care utilization plans and providing a foundation for further research into the matter.”
Adult Spinal Surgery in Patients with Previous THA: Should We Do the Spine First?
Presenting author: Bassel G. Diebo, MD
Patients with spine-hip syndrome could require both total hip arthroplasty (THA) and spinal fusions; however, the literature examining the outcomes of these patients when spinal fusion occurs after THA is conflicting. In this study, researchers aimed to determine the incidence of postoperative dislocation and THA in patients who underwent a spinal fusion following THA.
“For these patients, we wanted to further understand whether fusion length has a significant impact on postoperative complication rates,” said Bassel G. Diebo, MD.
In a retrospective review of 50,300 THA patients from the New York State Department of Health database, the researchers used ICD-9 codes to identify adult patients who underwent elective THA from 2009-2011. Patients who had subsequent spinal fusion (Short: 2-3 levels or Long: ≥4 levels) with diagnoses of degenerative disc disease (DDD) or adult idiopathic scoliosis (AIS) were also identified. Univariate analysis compared demographics, complications, subsequent THA, and readmissions between short, long and no spinal fusion groups. Multivariate binary logistic regression models controlling for age, gender and Deyo score were utilized to investigate the impact of spinal fusion on THA outcomes up to the end of 2013.
Based on their findings, the investigators believe this study demonstrates the complex interplay between the spinal fusion constructs and arthroplasty implants. Patients with prior THA who underwent spinal fusion had higher hip dislocation and need for revision THA. Moreover, the researchers found these risks to be higher in those patients with longer fusion constructs.
“When THA must be done first in patients with concomitant hip-spine pathology, spinopelvic parameters should be taken into account by the hip surgeon preoperatively in anticipation of what subsequent procedures the patient may have, especially if there is clinically significant sagittal malalignment,” Dr. Diebo said. “Regardless of the situation, communication and collaboration between hip and spine surgeons is crucial to optimizing outcomes for this patient population.”