The Impact of Smoking in Workers' Compensation Patients Receiving Spinal Cord Stimulation.

The objective of this study was to determine the impact of smoking on clinical outcomes in workers' compensation (WC) patients receiving spinal cord stimulation (SCS). One hundred and ninety-six patients from the Ohio Bureau of Workers' Compensation were identified who received SCS with implantation occurring between 2007-2012. Patients were divided into smokers (n = 120) and nonsmokers (n = 76). Population characteristics before and after implantation were analyzed between the two groups. A multivariate logistic regression was run to determine predictors of return to work (RTW) status. Our regression determined smoking (p = 0.006; odds ratio [OR] = 0.260) and body mass index (p = 0.036; OR = 0.905) to be negative predictors of RTW status. After implantation, smokers were less likely to RTW after 6 months and had higher pain scores after 6 and 12 months. Both smokers and nonsmokers had significance reductions in opioid use after SCS implantation. (Journal of Surgical Orthopaedic Advances 30(3):185-189, 2021).

The Effect of Diabetes Mellitus on Revision Discectomy after Single-level Lumbar Discectomy.

Diabetes currently affects over 25 million Americans, with the elderly carrying much of the disease burden. It's well known that diabetes increases the risk of surgical complications, but few studies have analyzed its effects on reoperation rates after single-level lumbar discectomy. Data was obtained using the commercially available Explorys software, which houses de-identified data for several healthcare systems. A database search was conducted to find all patients who'd undergone a lumbar discectomy. Scoliosis, spondylolisthesis, smoking history and obesity were excluded as possible confounding variables, after which 31,210 patients remained. Of them, 950 were found to have undergone a revision discectomy within 2 years. Those with diabetes were found to have a relative risk of 1.29 for revision discectomy compared to those who did not, 95% confidence interval (95% CI) 1.10-1.52, p < 0.002. These findings contribute to the importance of modifiable risk factor assessment preoperatively and their effects on surgical complications. (Journal of Surgical Orthopaedic Advances 29(3):159-161, 2020).

The Effect of Obesity on Revision Discectomy After Singlelevel Lumbar Discectomy.

The prevalence of obesity has been rising, creating a major public health concern. While several studies have shown obesity to increase the risk of surgical complications, few have analyzed its effects on reoperation, specifically after singlelevel lumbar discectomy. Data was obtained using the commercially available Explorys software that houses deidentified data for several major healthcare systems. A database search was used to find all patients who had undergone a lumbar discectomy. Scoliosis, spondylolisthesis, smoking history and depression were excluded as possible confounding variables, after which 25,960 patients remained. Of them, 690 were found to have undergone a revision discectomy within 2 years. Those who were obese were found to have a relative risk of 1.64 for revision discectomy compared to those who were nonobese, 95% confidence interval (95%CI) 1.322.03, p 0.0001. These findings contribute to the importance of modifiable risk factor assessment preoperatively and their effects on surgical complications. (Journal of Surgical Orthopaedic Advances 29(1):1012, 2020).

The Relationship Between Cigarette Smoking and the Prevalence, Frequency and Severity of Back Pain.

The purpose of this study was to examine the relationship between smoking and back pain in a cross-sectional analysis. Using the Osteoarthritis Initiative database, a multi-center, longitudinal, observational cohort study with 4796 participants, we examined the prevalence of back pain and of limitations in activity due to back pain, as well as the frequency and severity of back pain in participants who were current smokers compared to those who had never smoked. Data was evaluated using binary and ordinal logistic regression analyses. An increase in prevalence, frequency and severity of back pain was strongly associated with smoking. This demonstrates a relationship between smoking and back pain; however, further studies are needed to evaluate causation. (Journal of Surgical Orthopaedic Advances 29(3):165-168, 2020).

Multilevel Lumbar Fusion Is a Risk Factor for Lower Return to Work Rates Among Workers' Compensation Subjects With Degenerative Disc Disease.

Discogenic fusion is associated with variable outcomes, especially if multiple levels are fused. This study sought to determine the impact of fused levels on return to work (RTW) status in a workers' compensation (WC) setting. Nine hundred thirty-seven subjects were selected for study. The primary outcome was the ability to RTW within 2 years following fusion and to sustain this level for greater than 6 months. Many secondary outcomes were collected. A multivariate logistic regression model was used to determine the impact of multilevel fusion on RTW status. Of the multilevel fusion group, 21.7% met the RTW criteria versus 28.1% of the single-level fusion group (p < .028). Multilevel fusion was a negative predictor of RTW status (p < .041; OR 0.71). Additional negative predictors included prolonged time out of work, male gender, chronic opioid analgesia, and legal representation. Multilevel fusion led to poor clinical outcomes while overall RTW rates were low, which suggests a limited role of discogenic fusion within the WC setting. (Journal of Surgical Orthopaedic Advances 27(3):209-218, 2018).

Cervicothoracic Pedicle Morphometry: Using an Osteological Collection to Characterize Trends in Pedicle Size.

Pedicle screws are a common treatment option for spinal instability. Despite their popularity, pedicle screws carry the risk of transpedicular violation with subsequent neural and vascular damage. This study measured the pedicle dimensions of 500 dry specimens in an osteological collection. The data provide the orthopedic spine surgeon with an accurate measure of pedicle morphometry in light of previously limited and contradictory results. The study demonstrates that pedicle height at the cervicothoracic junction tends to increase with body height, particularly for females. Additionally, T1 pedicle width is smaller for females than males and, for males, tends to decrease with increasing body weight. These results are valuable to the spine surgeon because they suggest that taller patients may afford a larger margin for error in the vertical plane. However, they also demonstrate that heavier patients do not have wider pedicles and thus cannot be assumed to tolerate or require larger-diameter screws. (Journal of Surgical Orthopaedic Advances 27(1):33-38, 2018).

Lumbar Discography Is Associated With Poor Return to Work Status Following Lumbar Fusion Surgery in a Workers' Compensation Setting.

Lumbar discography (LD) is used to guide surgical decision making in patients with degenerative disc disease (DDD). Its safety and diagnostic accuracy are under contention. This study evaluates LD's efficacy within the workers' compensation (WC) population. Multivariate logistic regression analysis was used to determine the impact that undergoing LD before lumbar fusion for DDD had on return to work (RTW) rates among 1407 WC subjects. Discography was negatively associated with RTW status (p = .042; OR 0.76); 22.2% (142/641) of LD subjects met the RTW criteria, compared with 29.6% (227/766) of controls. Additional preoperative risk factors included psychological comorbidity (p < .001; OR 0.34), age greater than 50 (p < .005; OR 0.64), male gender (p < .037; OR 0.75), chronic opioid use (p < .001; OR 0.53), legal representation (p < .034; OR 0.72), and fusion technique (p < .043). LD subjects used postoperative narcotics for an average of 123 additional days (p < .001). This raises concerns regarding the utility of discography in the WC population. (Journal of Surgical Orthopaedic Advances 27(1):25-32, 2018).

Smoking is Associated with Increased Blood Loss and Transfusion Use After Lumbar Spinal Surgery.

BACKGROUND: Little is known about the association between smoking and intraoperative blood loss and perioperative transfusion use in patients undergoing spinal surgery. However, we found that although many of the common complications and deleterious effects of smoking on surgical patients had been well documented, the aspect of blood loss seemingly had been overlooked despite data reported in nonorthopaedic sources to suggest a possible connection. QUESTIONS/PURPOSES: We asked: (1) Is smoking associated with increased estimated blood loss during surgery in patients undergoing lumbar spine surgery? (2) Is smoking associated with increased perioperative transfusion usage? METHODS: Between 2005 and 2009, 581 lumbar decompression procedures (with or without fusion) were performed at one academic spine center. Of those, 559 (96%) had sufficient chart documentation to categorize patients by smoking status, necessary intra- and postoperative data to allow analysis with respect to bleeding and transfusion-related endpoints, and who did not meet exclusion criteria. Exclusion criteria included: patients whose smoking status did not fit in our two categories, patients with underlying coagulopathy, patients receiving anticoagulants (including aspirin and platelet inhibitors), history of hepatic disease, history of platelet disorder or other blood dyscrasias, and patient or family history of any other known bleeding disorder. Smoking history in packs per day was obtained for all subjects. We defined someone as a smoker if the patient reported smoking up until the day of their surgical procedure; nonsmokers were patients who quit smoking at least 6 weeks before surgery or had no history of smoking. We used a binomial grouping for whether patients did or did not receive a transfusion perioperatively. Age, sex, number of levels of discectomies, number of levels decompressed, number of levels fused, and use of instrumentation were recorded. The same approaches were used for transfusions in all patients regardless of smoking history; decisions were made in consultation between the surgeon and the anesthesia team. Absolute indications for transfusion postoperatively were: a hemoglobin less than 7 g/dL, continued symptoms of dizziness, tachycardia, decreased exertional tolerance, or hypotension that failed to respond to fluid resuscitation. Multiple linear regression analyses correcting for the above variables were performed to determine associations with intraoperative blood loss, while logistic regression was used to analyze perioperative transfusion use. RESULTS: After controlling for potentially relevant confounding variables noted earlier, we found smokers had increased estimated blood loss compared with nonsmokers (mean, 328 mL more for each pack per day smoked; 95% CI, 249-407 mL; p < 0.001). We also found that again correcting for confounders, smokers had increased perioperative transfusion use compared with nonsmokers (odds ratio, 13.8; 95% CI, 4.59-42.52). CONCLUSIONS: Smoking is associated with increased estimated surgical blood loss and transfusion use in patients undergoing lumbar spine surgery. Patients who smoke should be counseled regarding these risks and on smoking cessation before undergoing lumbar surgery. LEVEL OF EVIDENCE: Level III, therapeutic study.

Bilateral Pars Defects at the L4 Vertebra Result in Increased Degeneration When Compared With Those at L5: An Anatomic Study.

BACKGROUND: Cadaveric studies have examined disc degeneration at the L4-L5 and L5-S1 motion segments; however, we are not aware of another study that has examined the relationship between bilateral spondylolysis and its effect on degenerative disc disease at those levels. This may have been overlooked by researchers owing to the majority of spondylolysis occurring at the L5 vertebra. QUESTIONS/PURPOSES: Using osteologic specimens from a collection that included individuals who died in one city in the USA between 1893 and 1938, we asked: (1) do specimens with bilateral spondylolysis (bilateral pars defects) have increased levels of disc degeneration, at their respective motion segments, when compared with matched controls without spondylolysis, and (2) is the finding of a bilateral pars defect associated with more severe arthritis at L4-L5 than at L5-S1? METHODS: An observational study was performed on 665 skeletal lumbar spines from the Hamann-Todd Osteologic Collection at the Cleveland Museum of Natural History (Cleveland, OH, USA). The specimens included 534 males and 131 females ranging from 17 to 87 years old, with a nearly bell-shaped distribution of ages for males and a larger proportion of younger ages in the female specimens. Of those with spondylolysis, 81 had a defect at L5 and 14 had a defect at L4. The gross specimens were examined subjectively for evidence of arthrosis. At the time of examination, specific attention was not paid to the coexisting presence or absence of spondylolysis nor was the examiner blinded to the age of the specimens. Disc degeneration was measured by the classification of Eubanks et al., a modified version of the Kettler and Wilke classification. Linear regression was performed to derive a formula that would predict the amount of disc degeneration at L4-L5 and L5-S1 for the normal control population given a specimen's age, sex, and race. We then used this formula to evaluate the difference in disc degeneration at the corresponding level of the pars defect that is greater than the predicted amount for a control without spondylolysis. This allowed us to conclude that any significant differences found between the L4-L5 and L5-S1 cohorts were attributable to factors not simply inherent to their functional position in the spine of an individual without a bilateral pars defect. RESULTS: L4 spondylolysis and L5 spondylolysis showed greater amounts of degeneration compared with that of matched controls (L4 controls: mean = 1.52, SD = 0.74; L4 spondylolysis: mean = 3.21, SD = 0.87; p < 0.001; L5 controls: mean = 0.97, SD = 0.48; L5 spondylolysis: mean = 2.06, SD = 0.98; p < 0.001). When we controlled for the expected amount of degenerative disc disease at each level in controls, the observed degeneration was more severe at L4-L5 than at L5-S1 (p = 0.008, R-squared = 18.6). CONCLUSIONS: L4-L5 and L5-S1 bilateral spondylolysis groups had increased presence of degenerative disc disease compared with those without bilateral spondylolysis. For the same degree of spondylolysis, the observed amount of disc degeneration was greater at the L4-5 motion segment compared with L5-S1. CLINICAL RELEVANCE: Although not as common as the spondylolysis at L5-S1, we believe that our findings support that patients with L4-L5 spondylolysis can expect a greater degree of degenerative disc disease and increasing clinical symptoms. Multiple factors in the sacropelvic geometry of an individual, facet morphologic features at L4-L5, and the absence of the iliolumbar ligament at this level are possible contributing factors to the findings of this study.

Can Internet information on vertebroplasty be a reliable means of patient self-education?

BACKGROUND: Studies of the quality and accuracy of health and medical information available on the Internet have shown that many sources provide inadequate information. However, to our knowledge, there are no published studies analyzing the quality of information available online regarding vertebroplasty. Because this has been a high-volume procedure with highly debated efficacy, it is critical that patients receive complete, accurate, and well-balanced information before deciding a treatment course. Additionally, few studies have evaluated the merit of academic site authorship or site certification on information quality, but some studies have used measurements of quality that are based primarily on subjective criteria or information accuracy rather than information completeness. QUESTIONS/PURPOSES: The purposes of our study were (1) to evaluate and analyze the information on vertebroplasty available to the general public through the Internet; (2) to see if sites sponsored by academic institutions offered a higher quality of information; and (3) to determine whether quality of information varied according to site approval by a certification body. METHODS: Three search engines were used to identify 105 web sites (35 per engine) offering information regarding vertebroplasty. Sites were evaluated for authorship/sponsorship, content, and references cited. Information quality was rated as "excellent," "high," "moderate," "low," or "unacceptable." Sites also were evaluated for contact information to set up an appointment. Data were analyzed as a complete set, then compared between authorship types, and finally evaluated by certification status. Academic sites were compared with other authorship groups and certified sites were compared with noncertified sites using Student's t-test. RESULTS: Appropriate indications were referenced in 74% of sites, whereas only 45% discussed a contraindication to the procedure. Benefits were expressed by 100% of sites, but risks were outlined in only 53% (p < 0.001). Ninety-nine percent of sites provided step-by-step descriptions of the procedure, and 44% of sites also included images. Alternative treatments were mentioned by 51% of sites. Twenty-seven percent of sites referenced peer-reviewed literature, 41% offered experiential or noncited data based on American populations, and 7% offered analogous data from international populations. Thirty percent of sites provided contact information for patient appointment scheduling. Seven percent of sites were classified as excellent quality, 6% as high quality, 11% as moderate quality, 19% as poor quality, and 57% as unacceptable. Sixteen percent of sites were sponsored by academic institutions, 62% by private groups, 8% by biomedical device companies, and 14% were sponsored otherwise. Academic sites reported fewer risks of the procedure than private sites or other sites (p = 0.05 and p = 0.04), but reported more risks than industry sites (p = 0.007). Academic sites were more likely than sites classified as other to offer contact information for patient appointment scheduling (p = 0.004). Nine percent of sites evaluated were Health on the Net Foundation (HONCode) certified. No association with improved information quality was observed in these sites relative to noncertified sites (all p > 0.05). CONCLUSIONS: Internet information regarding vertebroplasty is not only inadequate for proper patient education, but also potentially misleading as sites are more likely to present benefits of the procedure than risks. Although academic sites might be expected to offer higher-quality information than private, industry, or other sites, our data would suggest that they do not. HONCode certification cannot be used reliably as a means of qualifying website information quality. Academic sites should be expected to set a high standard and alter their Internet presence with adequate information distribution. Certification bodies also should alter their standards to necessitate provision of complete information in addition to emphasizing accurate information. Treating physicians may want to counsel their patients regarding the limitations of information present on the Internet and the pitfalls of current certification systems. LEVEL OF EVIDENCE: Level IV, economic and decision analyses. See the Instructions for Authors for a complete description of levels of evidence.

The Effect of High-Normal Preoperative International Normalized Ratios on Outcomes and Complications After Anterior Cervical Spine Surgery.

Hematoma after anterior cervical spine surgery can result in neurologic and airway compromise. Current guidelines recommend an international normalized ratio (INR) <1.5 before elective spine surgery because of increased complications. The risk associated with an INR of 1.25 is not well studied. The purpose of this study was to determine the risk of complications associated with a preoperative INR >1.25 and ≤1.5 in patients undergoing elective anterior cervical spine surgery. The American College of Surgeons National Surgical Quality Improvement Program database was queried. Patients undergoing elective anterior cervical spine surgery from 2012 to 2016 who had an INR recorded within 24 hours of surgery were included. Outcomes of interest included postoperative hematoma requiring surgery, 30-day mortality, and 30-day readmissions and reoperations. A total of 2949 patients were included. The incidence of a postoperative hematoma that required surgical management was 0.2%, 0.6%, and 4.5% in the INR≤1, 11.25 and ≤1.5 before elective anterior cervical spine surgery is associated with significantly higher rates of postoperative hematoma formation as well as 30-day readmission and reoperation; there was a trend toward significance in mortality rate. [Orthopedics. 2024;47(1):e26-e32.].

Volar and Dorsal Blood Supply to the Lunate: A Cadaveric Study.

Although various studies have proposed vascular and mechanical factors, the etiology of Kienböck disease is unknown. Kienböck theorized that lunatomalacia resulted from traumatic disruption of blood supply and bony nutrition to the lunate. Extraosseous supply to the lunate, as far as volar or dorsal vessels are concerned, is still controversial. This study evaluated the extraosseous nutrient foramina from the dorsal and volar aspects of lunate specimens. A total of 913 specimens from the Hamann-Todd Osteological Collection in Cleveland, Ohio, were examined. The nutrient artery foramina on left and right lunate specimens were examined from dorsal and volar aspects. The number of nutrient artery foramen was tabulated. Age, sex, and race data were collected. Specimens were divided into groups according to the number of nutrient artery foramina, and the dorsal and volar foramina were compared. The average number of foramina on the dorsal aspect of the lunate (1.71) was greater than the volar aspect (1.64), except in specimens younger than 35 years. A greater number of specimens had 3 or more foramina on the dorsal side compared with the volar aspect. Based on this study, there was significant contribution of dorsal arterial vessels to the blood supply of lunate specimens older than 35 years, which contrasts with findings in earlier studies. The disruption of dorsal intercarpal and radiocarpal ligaments leading to the disruption of the dorsal arterial arches may contribute to vascular insufficiency of the lunate and should be evaluated further in the etiopathogenesis of Kienböck disease. [Orthopedics. 2021;44(2):e243-e247.].

Time to Surgery Affects Return to Work Rates for Workers' Compensation Patients With Single-Level Lumbar Disk Herniation.

The optimal timing of lumbar diskectomy in patients with lumbar disk herniation and radiculopathy has not been studied in the workers' compensation (WC) population. A total of 10,592 patients received lost-work compensation from the Ohio Bureau of Workers' Compensation for a lumbar disk herniation between 2005 and 2012. The primary outcome was whether subjects return to work (RTW). To determine the impact time to surgery had on RTW status, the authors performed a multivariate logistic regression analysis. They compared other secondary outcomes using chi-square and t tests. The authors identified 1287 WC patients with single-level disk herniation and radiculopathy. Average time from injury to surgery was 364 days (range, 2-2710 days). The WC patients with shorter duration of radiculopathy before diskectomy had higher RTW rates; fewer physical therapy, chiropractic, and psychotherapy sessions; and fewer postoperative diagnoses of psychological illnesses (P<.05). A multivariate logistic regression model showed that time to surgery was an independent, negative predictor of RTW (odds ratio [OR], 0.97 per month; P<.01). Legal representation (OR, 0.56; P<.01), psychological comorbidity (OR, 0.32; P=.01), and mean household income (OR, 1.01 per $1000; P<.01) also significantly affected RTW status. These results confirm that the duration of radiculopathy due to single-level lumbar disk herniation has a predictive value for the WC population undergoing diskectomy. Within 12 weeks of injury, post-diskectomy patients do reasonably well, with 70.0% of subjects returning to work. [Orthopedics. 2021;44(1):e43-e49.].

Symptomatic Epidural Hematoma after Elective Posterior Lumbar Decompression: Incidence, Timing, Risk Factors, and Associated Complications.

BACKGROUND: Symptomatic post-operative lumbar epidural hematoma (PLEH) is a complication of lumbar spine surgery that can cause permanent neurologic consequences through compression of the cauda equina and nerve roots. QUESTIONS/PURPOSES: We sought to investigate the incidence, timing, and risk factors for symptomatic epidural hematomas following posterior lumbar decompression, as well as to identify additional post-operative complications associated with symptomatic lumbar epidural hematomas. METHODS: Elective lumbar spine procedures were identified in the National Surgical Quality Improvement Program (NSQIP) database between 2012 and 2016. Analyzed predictors of reoperation or readmission within 30 days for symptomatic PLEH included demographics, comorbidities, pre-operative laboratory values, peri-operative characteristics, and post-operative complications. RESULTS: There were 75,878 cases included in the analysis. The incidence rate of symptomatic PLEH was 0.27% (n = 206), 54.4% (n = 112) of which occurred within 5 days of the procedure. Increased age, obesity (body mass index of 35 or higher), peri-operative transfusion, multilevel surgery (two or more levels), dural tear repair, and microscope use were independently associated with PLEH. Post-operative complications associated with PLEH included surgical site infection and urinary tract infection. CONCLUSIONS: Readmission or reoperation for symptomatic PLEH following elective lumbar spine surgery is rare and can occur many days or weeks after a procedure. There are modifiable risk factors for PLEH and associated additional post-operative complications that physicians should be suspicious of following posterior lumbar decompression.

Effect of Nicotine Dependence and Smoking on Revision Diskectomy After Single-Level Lumbar Diskectomy.

Removal of a herniated disk that is causing neural compression is among the most common indications for spinal surgery. Previous population database studies of risk factors for reoperation after this procedure analyzed small to medium numbers of patients. To date, no study has concurrently assessed the effect of modifiable risk factors, such as smoking and nicotine dependence, with a large number of patients. Data were obtained with commercially available software that houses de-identified data for several major US health care systems. A database search was conducted to find all patients who had undergone lumbar diskectomy. Obesity, scoliosis, spondylolisthesis, and depression were excluded as possible confounding variables. The remaining patients were divided into smoking and nonsmoking groups. Those who had undergone revision lumbar diskectomy within 2 years were counted. Pearson's chi-square statistical test was used to determine significance at P<.05. Of the 50 million patient records in the software platform, 53,360 patients were identified who had undergone single-level lumbar diskectomy. Of these, 26,980 fulfilled the inclusion criteria. A total of 890 of those patients had undergone revision lumbar diskectomy within 2 years of their original procedure. Those who smoked were found to have a relative risk of 2.47 compared with nonsmokers (95% confidence interval, 2.17-2.82; P<.0001). Nicotine dependence and smoking had a significant effect on the rate of reoperation. These findings support the importance of preoperative assessment of modifiable risk factors and their effects on surgical complications. [Orthopedics. 2020;43(5):e438-e441.].

Shorter Time to Surgery Is Associated With Better Outcomes for Spondylolisthesis in the Workers' Compensation Population.

This study sought to determine the impact of time to surgery on clinical outcomes in patients with spondylolisthesis in the workers' compensation (WC) population. There is conflicting evidence regarding the effect of time to surgery on patients with spondylolisthesis. Patients receiving WC are known to have worse outcomes following spine surgery compared with the general population. A total of 791 patients from the Ohio Bureau of Workers' Compensation were identified who underwent lumbar fusion for spondylolisthesis between 1993 and 2013. The patients were divided into those who had surgery within 2 years of injury date and after 2 years. Confounding factors were corrected for in a multivariate logistic regression to determine predictors of return to work (RTW) status. Multivariate logistic regression determined that longer time to surgery (P=.003; odds ratio, 0.89 per year), age at index fusion (P=.003; odds ratio, 0.98 per year), and use of physical therapy before fusion (P=.008; odds ratio, 0.54) were negative predictors of RTW status. Patients who had surgery within 2 years were more likely to RTW and have fewer days absent from work, lower medical costs, and fewer sessions of psychotherapy, physical therapy, and chiropractor care. The authors demonstrated that for WC patients with spondylolisthesis, longer time to surgery was a negative predictor of RTW status. Patients who had surgery within 2 years of injury date were significantly more likely to RTW compared with after 2 years. [Orthopedics. 2020;43(3):154-160.].

30-day Mortality Following Surgery for Spinal Epidural Abscess: Incidence, Risk Factors, Predictive Algorithm, and Associated Complications.

STUDY DESIGN: Retrospective case-control study. OBJECTIVE: To determine incidence and timing of mortality following surgery for spinal epidural abscess (SEA), identify risk factors for mortality, and identify complications associated with mortality. SUMMARY OF BACKGROUND DATA: SEA is a serious condition with potentially devastating sequelae. There is a paucity of literature characterizing mortality following surgery for SEA. METHODS: The National Surgical Quality Improvement Program (NSQIP) database was used. Patients with a diagnosis of SEA were included. A Cox proportional hazards model identified independent risk factors for 30-day mortality. A predictive model for mortality was created. Multivariate models identified postoperative complications associated with mortality. RESULTS: There were 1094 patients included, with 40 cases of mortality (3.7%), the majority of which occurred within 2 weeks postoperatively (70%). Independent risk factors for 30-day mortality were age>60 years (hazard ratio [HR]: 2.147, P = 0.027), diabetes (HR: 2.242, P = 0.015), respiratory comorbidities (HR: 2.416, P = 0.037), renal comorbidities (HR: 2.556, P = 0.022), disseminated cancer (HR: 5.219, P = 0.001), and preoperative thrombocytopenia (HR: 3.276, P = 0.001). A predictive algorithm predicts a 0.3% mortality for zero risk factors up to 37.5% for 4 or more risk factors. A ROC area under curve (AUC) was 0.761, signifying a fair predictor (95% CI: 0.683-0.839, P < 0.001). Cardiac arrest (adjusted odds ratio [aOR]: 72.240, 95% confidence interval [CI]: 27.8-187.721, P < 0.001), septic shock (aOR: 15.382, 95% CI: 7.604-31.115, P < 0.001), and pneumonia (aOR: 2.84, 95% CI: 1.109-7.275, P = 0.03) were independently associated with mortality. CONCLUSION: The 30-day mortality rate following surgery for SEA was 3.7%. Of the mortalities that occurred within 30 days of surgery, the majority occurred within 2 weeks. Independent risk factors for mortality included older age, diabetes, hypertension, respiratory comorbidities, renal comorbidities, metastatic cancer, and thrombocytopenia. Risk for mortality ranged from 0.3% to 37.5% based on number of risk factors. Septic shock, cardiac arrest, and pneumonia were associated with mortality. LEVEL OF EVIDENCE: 3.

The Effect of Age on the Benefits of Early Decompression for Cervical Spondylotic Myelopathy.

Cervical myelopathy is the most common cause of acquired spinal cord dysfunction in people aged >55 years. Advanced age and duration of symptoms have been implicated in the literature as negative prognostic indicators for postoperative functional improvement, but very few studies have evaluated the interaction of these factors. We retrospectively reviewed 125 patients who underwent surgery for cervical myelopathy. Patients were stratified according to age greater or less than 65 years and duration of symptoms of greater or less than 12 and 24 months. Functional outcomes were assessed using the Nurick score. Simple regression and multiple regression analyses were done, controlling for sex, preoperative Nurick score, surgical approach, smoking status, diabetes status, prior surgery, number of levels fused, ethanol use, and signal change on preoperative magnetic resonance imaging. The average change in Nurick score in all patients was 1.36, with a significant difference between patients with symptoms for <24 months and those with symptoms for >24 months (1.54 vs 0.98, P = .03). Multiple regression analysis revealed that older patients had a significant difference at 24 months (1.69 vs 1.25, P = .01), whereas younger patients showed slightly lower improvement overall and a change in Nurick score at both thresholds that was statistically nonsignificant.

The Association Between Body Mass Index and the Prevalence, Severity, and Frequency of Low Back Pain: Data From the Osteoarthritis Initiative.

STUDY DESIGN: Cross-sectional study. OBJECTIVE: To determine whether there is an association between body mass index (BMI) and the prevalence, severity, and frequency of low back pain and identify other potential patient risk factors for the development of low back pain. SUMMARY OF BACKGROUND DATA: Many studies have implicated that a high BMI is a risk factor for low back pain. However, few studies have examined the association between increased BMI and the prevalence, severity, and frequency of low back pain. METHODS: Data from the Osteoarthritis Initiative, a multicenter, prospective study of knee osteoarthritis, were used to conduct this study, which included 4796 patients. BMI was categorized according to the World Health Organization classification and the prevalence, severity, and frequency of low back pain were assessed. Logistic regression was performed to identify additional patient risk factors associated with low back pain. RESULTS: The prevalence of low back pain was found to be significantly higher in patients with an elevated BMI compared to those with normal or underweight BMI and demonstrated a stepwise increase with each BMI category. Approximately 47.4% of patients with normal or underweight BMI complained of low back pain compared with 72.8% of morbidly obese patients (P < 0.0001). No association was seen between BMI and the frequency or severity of low back pain episodes. Osteoarthritis of the back and depression were patient variables found to be associated with all three measures (prevalence, severity, and frequency) of low back pain. CONCLUSION: Elevated BMI is strongly associated with an increased prevalence of low back pain. Depression and osteoarthritis of the back are associated with the prevalence, severity, and frequency of low back pain. LEVEL OF EVIDENCE: 3.

Preoperative Opioid Use: A Risk Factor for Poor Return to Work Status After Single-level Cervical Fusion for Radiculopathy in a Workers' Compensation Setting.

STUDY DESIGN: Retrospective comparative case-control study. OBJECTIVES: The objectives of this study are: (1) How preoperative opioid use impacts RTW status after single-level cervical fusion for radiculopathy? and (2) What are other postsurgical outcomes affected by preoperative opioid use? SUMMARY OF BACKGROUND DATA: Opioid use has increased significantly in the past decade. The use of opioids has a drastic impact on workers' compensation population, an at-risk cohort for poorer surgical and functional outcomes than the general population. METHODS AND MATERIALS: Data was retrospectively collected from Ohio Bureau of Workers' Compensation between 1993 and 2011. The study population included patients who underwent single-level cervical fusion for radiculopathy as identified by current procedural terminology codes and International Classification of Diseases-9 codes. On the basis of opioid use before surgery, two groups were constructed (opioids vs. non-opioids). Using a multivariate logistic regression model, the effect of preoperative opioid use on return to work (RTW) status after fusion was analyzed and compared between the groups. RESULTS: In the regression model, preoperative opioid use was a negative predictor of RTW status within 3-year follow-up after surgery. Opioid patients were less likely to have stable RTW status [odds ratio (OR), 0.50; 95% confidence interval (CI), 0.38-0.65; P=0.05] and were less likely to RTW within the first year after surgery (OR, 0.50; 95% CI, 0.37-0.66; P=0.05) compared with controls. Stable RTW was achieved in 43.3% of the opioids group and 66.6% of control group (P=0.05). RTW rate within the first year after fusion was 32.5% of opioids group and 57% of control group (P<0.05).Reoperation and permanent disability rates after surgery were higher in the opioid group compared with the control group (P<0.05). CONCLUSIONS: In a workers' compensation, patients with work-related injury who underwent single-level cervical fusion for radiculopathy and received opioids before surgery had worse RTW status, a higher reoperation rate, and higher rate of awarded permanent disability after surgery.