Faculty Bibliography

STUDY DESIGN:This study was a retrospective cohort database study which looked at the relationship between myocardial reinfarction following lumbar spine surgery. OBJECTIVE:Current study aimed to determine the risk of reinfarction associated with the time between initial myocardial infarction (MI) and lumbar spine surgery, type of lumbar surgical procedure, and other risk factors. SUMMARY OF BACKGROUND INFO:Several studies have demonstrated a strong temporal pattern between postoperative reinfarction rate and the period between previous MI and surgery. To the best of our knowledge, no study has looked specifically at the temporal relationship between previous MI, lumbar spine surgery and incidence of postoperative myocardial reinfarction. MATERIALS AND METHODS:The Humana database was analyzed from Q1 2007 through Q3 2016 and the Medicare database was analyzed from Q1 2005 through Q4 2014. Patients were placed into 1 of 5 groups based on time between MI and surgery: 0-3, 4-6, 7-12, 13-24, and 25+ months. Reinfarction rates were determined in these groups. Age, sex, and type of surgery were analyzed to determine association with postoperative reinfarction rates. RESULTS:There was a strong correlation between postoperative myocardial reinfarction and lumbar spine surgery occurring 0-3 months after the patient's initial MI (P<0.01). Those patients had a risk ratio >3 (P<0.01) compared with patients who underwent lumbar spine surgery after an interval >3 months between initial MI and lumbar spine surgery. In addition, spinal fusion procedures were associated with a greater risk of postoperative myocardial reinfarction than nonfusion procedures. CONCLUSION:In both databases, there was a clinically relevant and statistically significant increase in myocardial reinfarction in patients who experienced an MI 0-3 months before lumbar spine surgery. We believe that the current study helps in treatment planning for patients with a history of MI who are considering spine surgery. LEVEL OF EVIDENCE:Level III.

Growth of long bones and vertebrae is maintained postnatally by a long-lasting pool of progenitor cells. Little is known about the molecular mechanisms that regulate the output and maintenance of the cells that give rise to mature cartilage. Here we demonstrate that postnatal chondrocyte-specific deletion of a transcription factor Stat3 results in severely reduced proliferation coupled with increased hypertrophy, growth plate fusion, stunting and signs of progressive dysfunction of the articular cartilage. This effect is dimorphic, with females more strongly affected than males. Chondrocyte-specific deletion of the IL-6 family cytokine receptor gp130, which activates Stat3, phenocopied Stat3-deletion; deletion of Lifr, one of many co-receptors that signals through gp130, resulted in a milder phenotype. These data define a molecular circuit that regulates chondrogenic cell maintenance and output and reveals a pivotal positive function of IL-6 family cytokines in the skeletal system with direct implications for skeletal development and regeneration.

PURPOSE:This study evaluates the influence of patient frailty status on postoperative complications in those receiving single-level lumbar fusion surgery. METHODS:The nationwide readmission database was retrospectively queried between 2016 and 2017 for all patients receiving single-level lumbar fusion surgery. Readmissions were analyzed at 30, 90, and 180 days from primary discharge. Demographics, frailty status, and relevant complications were queried at index admission and all readmission intervals. Complications of interest included infection, urinary tract infection (UTI), posthemorrhagic anemia, inpatient length of stay (LOS), and adjusted all-payer costs. Nearest-neighbor propensity score matching for demographics was implemented to identify non-frail control patients with similar diagnoses and procedures. The analysis used nonparametric Mann-Whitney U testing and odds ratios. RESULTS:Comparing propensity-matched cohorts revealed significantly greater LOS and total all-payer inpatient costs in frail patients than non-frail patients with comparable demographics and comorbidities (p < 0.0001 for both). Furthermore, frail patients encountered higher rates of UTI (OR: 3.97, 95%CI: 3.21-4.95, p < 0.0001), infection (OR: 6.87, 95%CI: 4.55-10.86, p < 0.0001), and posthemorrhagic anemia (OR: 1.94, 95%CI: 1.71-2.19, p < 0.0001) immediately following surgery. Frail patients had significantly higher rates of 30-day (OR: 1.24, 95%CI: 1.02-1.51, p = 0.035), 90-day (OR: 1.38, 95%CI: 1.17-1.63, p < 0.001), and 180-day (OR: 1.55, 95%CI: 1.30-1.85, p < 0.0001) readmissions. Lastly, frail patients had higher rates of infection at 30-day (OR: 1.61, 95%CI: 1.05-2.46, p = 0.027) and 90-day (OR: 1.51, 95%CI: 1.07-2.16, p = 0.020) readmission intervals. CONCLUSIONS:Patient frailty status may serve as an important predictor of postoperative outcomes in patients receiving single-level lumbar fusion surgery.

STUDY DESIGN/METHODS:Retrospective cohort study. OBJECTIVE:The aim of this study was to compare different aspects of fusion surgery in patients with osteoporosis with regard to graft subtype and surgical approach. SUMMARY OF BACKGROUND DATA/BACKGROUND:Osteoporosis and chronic lower back pain are common in elderly populations and significantly increase the risk of compression fractures within the spine. METHODS:Using the 2016-2017 National Readmission Database we identified 11,086 osteoporotic patients who received lumbar fusion using ICD-10 coding. Information regarding biologic graft type and surgical approach was collected. Patients were stratified by number of levels fused. Perioperative complications were collected at 30-, 90-, and 180-day follow-up intervals. Statistical analysis included univariate testing and multivariate regression modeling, controlling for patient demographics and comorbidities. RESULTS:Patients receiving single-level fusion with autologous grafts had higher rates of hardware failure (P = 0.00014) at 30-day follow-up and 90-day follow-up (P < 0.0001) and higher rates of lumbar vertebral fractures at 90-day follow-up (P = 0.045) compared to those treated with nonautologous grafts. Patients receiving lumbar fusion with anterior and posterior approaches had no difference in readmission or infection rates, but the anterior approach was associated with a higher cost. CONCLUSION/CONCLUSIONS:In this study, osteoporotic patients treated with autologous grafts had higher rates of complications compared to those treated with nonautologous grafts. Anterior and posterior approaches had similar complication rates; however, the anterior approach was associated with a higher total cost.Level of Evidence: 4.

STUDY DESIGN:This was a large database study. OBJECTIVE:The objective of this study was to compare the incidence of complications and reoperation rates between the most common surgical treatments for cervical spondylotic myelopathy (CSM): anterior cervical discectomy and fusion (ACDF), anterior cervical corpectomy and fusion (ACCF), and posterior laminectomy and fusion (Lamifusion). SUMMARY OF BACKGROUND DATA:CSM is a major contributor to disability and reduced quality of life worldwide. METHODS:Humana insurance database was queried for CSM diagnoses between 2007 and 2016. The initial population was divided based on the surgical treatment and matched for age, sex, and Charlson Comorbidity index. Specific postoperative complications or revisions were analyzed at individual time points. Pearson χ2 analysis with Yate continuity correction was used. RESULTS:Lamifusion had significantly higher rates of wound infection/disruption than ACDF or ACCF (5.03%, 2.19%, 2.29%; P=0.0008, 0.002, respectively) as well as iatrogenic deformity (4.75%, 2.19%, 2.10%; P=0.0036, 0.0013). Lamifusion also had a significantly higher rate of shock and same-day transfusion than ACDF (4.75%, 2.01%, P=0.0005), circulatory complications (2.01%, <1%, P=0.0183), and C5 palsy (4.84%, 1.74%, P≤0.0001). Compared with ACDF, Lamifusion had higher rates of hardware complication (3.29%, 2.01%, P=0.0468), and revision surgery (8.23% 5.85%, P=0.0395). Lamifusion had significantly lower rates of dysphagia than either ACDF (3.93% vs. 6.58%, P=0.0089) or ACCF (3.93% vs. 8.59%, P<0.0001). When comparing ACCF to ACDF, ACCF had significantly higher rates of circulatory complications (2.38%, <1%, P=0.0053), shock/same-day transfusion (3.2%, 2.0%, P=0.59), C5 palsy (3.47%, 1.74%, P=0.0108), and revision surgery (9.51%, 5.85%, P=0.0086). CONCLUSIONS:The data shows that posterior Lamifusion has higher overall rate of complications compared with ACDF or ACCF. Furthermore, when comparing the anterior approaches, ACDF was associated with lower rate of complication and revision. ACCF had the highest overall rate of revision surgery.

OBJECTIVE:The aim of the current study was to classify and analyze trends in lumbar disc degeneration across age, sex, and disc level using weightbearing kinematic MRI. MATERIALS AND METHODS/METHODS:Between January 2019 and July 2019, 1198 cases were retrospectively analyzed with kinematic MRI. Patients were divided into 5 groups based on age (20-29, 30-39, 40-49, 50-59, and 60+) and evaluated using the Pfirrmann classification to assess for disc degeneration at 5 vertebral levels: L1/2, L2/3, L3/4, L4/5, and L5/S1. Trends in degeneration were analyzed with regression and time series. RESULTS:The L5/S1 vertebral disc had the highest prevalence of severe degeneration across all age groups. The most common multi-level degeneration combinations were L4/5 and L5/S1 for two levels and L3/4, L4/5, and L5/S1 for three levels. All vertebral levels showed significant difference in mean Pfirrmann grade among the age groups (p < 0.001 at all levels). Statistically significant differences in mean Pfirmmann grade among males and females were found only in ages 20-29 and 30-39, in which males showed more degeneration. CONCLUSION/CONCLUSIONS:Our findings using kinematic MRI demonstrate that degeneration increases with age and is most severe in the L5/S1 disc. In multi-level degeneration the most prevalent combinations are those that are contiguous and include L5/S1. Young males were more likely to have degeneration than young females, but there was no significant difference from the fifth decade of life on.

»:Lumbar disc herniation is one of the most common spinal pathologies, often occurring at the L4-L5 and L5-S1 levels. The highest incidence has been reported in patients between the fourth and sixth decades of life. »:The severity of symptoms is influenced by the patient's risk factors, the location, and the extent and type of disc herniation. »:Lumbar disc herniation can be effectively treated with multiple treatment protocols. In most cases, first-line treatment includes oral analgesic medication, activity modification, and physical therapy. When nonoperative treatments do not provide adequate relief, patients may elect to undergo a fluoroscopically guided contrast-enhanced epidural steroid injection. A subgroup of patients whose condition is refractory to any type of nonoperative modalities will proceed to surgery, most commonly an open or minimally invasive discectomy. »:The treatment algorithm for symptomatic lumbar disc herniation often is a stepwise approach: failure of initial nonoperative measures leads to more aggressive treatment when symptoms mandate and, as such, necessitates the use of a multidisciplinary team approach. The core team should consist of an interventional physiatrist, an orthopaedic surgeon, a physician assistant, and a physical therapist. Additional team members may include nurses, radiologists, neurologists, anesthesiologists, spine fellows, psychologists, and case managers. »:This review article describes a case scenario that uses a multidisciplinary team approach for the treatment of an acute L4-L5 disc herniation in a 31-year-old patient without any major comorbidities.

STUDY DESIGN:Systematic review. OBJECTIVE:To characterize the effects of postoperative physical therapy (PT) after surgery for cervical spondylosis on patient-reported outcomes and impairments. Secondarily, to identify associated complications, adverse effects, and health care costs with postoperative PT, and to describe the content, timing, and duration of the PT. SUMMARY OF BACKGROUND DATA:Cervical spine surgery is common; however, it is unclear if the addition of postoperative PT leads to improved patient outcomes and decreased health care costs. MATERIALS AND METHODS:PubMed, Embase, Cochrane Central Register of Controlled Trials, Physiotherapy Evidence Database, and Web of Science were searched until July 2019. All peer-reviewed articles involving cervical spine surgery with postoperative PT for cervical spondylosis were considered for inclusion. Risk of bias was assessed using the Revised Cochrane risk-of-bias tool for randomized trials. Findings were described narratively, and GRADE approach was used to define the quality of evidence. RESULTS:A total of 10,743 studies were screened. Six studies met inclusion criteria; 2 randomized controlled trials and 4 subsequent follow-up studies containing study arms that included postoperative PT after cervical spine surgery. Meta-analysis was not performed due to study heterogeneity and no study compared PT+surgery to surgery alone. PT treatment included exercise therapy, cognitive behavioral therapy, and optional vestibular rehabilitation. Included studies indicated PT appeared to have positive effects on patient outcomes, however, there were no treatment control groups and the quality of evidence was very low to low. Timing, duration, and content of PT programs varied. No studies reported complications, adverse effects, or cost-effectiveness relating to PT after surgery. CONCLUSIONS:Current literature prevents a definitive conclusion regarding the impact of postoperative PT, given the lack of treatment control groups. PT treatment was limited to exercise therapy, cognitive behavioral therapy, and optional vestibular rehabilitation in the included studies. PT treatment varied, limiting consistent recommendations for content, timing, and treatment duration. Controlled trials are needed to determine the effectiveness of the addition of postoperative PT following cervical spine surgery for cervical spondylosis. LEVEL OF EVIDENCE:Level II.

STUDY DESIGN:This was a retrospective cohort study. OBJECTIVE:The aim of this study was to compare the hospital charges and postoperative complications of minimally invasive surgery (MIS) and open approaches to sacroiliac joint (SIJ) fusion. SUMMARY OF BACKGROUND DATA:The data source utilized in this study is the Healthcare Cost and Utilization Project National Readmission Database (NRD) from 2016 and 2017. The NRD is a yearly nationally representative inpatient database from the Agency for Healthcare Research and Quality with information regarding patient demographics, diagnoses, procedures, and readmissions. MATERIALS AND METHODS:The 2016-2017 NRD was used to identify 2521 patients receiving SIJ fusion with open (n=1990) or MIS approaches (n=531) for diagnosed sacrum pain, sacroiliitis, sacral instability, or spondylosis after excluding for those who received prior SIJ fusion, those diagnosed with neoplasms or trauma of the pelvis or sacrum, and nonelective procedures. We then one-to-one propensity-matched the open (n=531) to the MIS approach (n=531) for age, sex, and Charlson Comorbidity Index. Statistical analysis was performed to compare total hospital charges, immediate surgical complications, nonelective readmission rate, and 30-, 90-, and 180-day postoperative complications between the 2 approaches. RESULTS:The mean total hospital charge was the only significant difference between 2 group. Open SIJ fusion had significantly higher charge compared with the MIS approach (open $101,061.90±$81,136.67; MIS $83,594.78±$49,086.00, P<0.0001). The open approach was associated with nonsignificant higher rates of novel lumbar pathology at 30-, 90-, and 180-day readmissions and revision surgeries at 30 and 180 days. MIS approach had higher rates nervous system complications at 30-, 90-, and 180-day readmission, as well as infection and urinary tract infection within 30 days, none being significant. Novel postprocedural pain was similar between the 2 groups at 90 and 180 days. CONCLUSIONS:The current study found that open SIJ fusion was associated with significantly higher hospital charges. Although no significant differences in postoperative complications were found, there were several notable trends specific to each surgical approach.