Browsing by Author "Kopjar, Branko"
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Item Open Access Anterior versus posterior surgical approaches to treat cervical spondylotic myelopathy: outcomes of the prospective multicenter AOSpine North America CSM study in 264 patients.(Spine, 2013-12) Fehlings, Michael G; Barry, Sean; Kopjar, Branko; Yoon, Sangwook Tim; Arnold, Paul; Massicotte, Eric M; Vaccaro, Alexander; Brodke, Darrel S; Shaffrey, Christopher; Smith, Justin S; Woodard, Eric; Banco, Robert J; Chapman, Jens; Janssen, Michael; Bono, Christopher; Sasso, Rick; Dekutoski, Mark; Gokaslan, Ziya LStudy design
A prospective observational multicenter study.Objective
To help solve the debate regarding whether the anterior or posterior surgical approach is optimal for patients with cervical spondylotic myelopathy (CSM).Summary of background data
The optimal surgical approach to treat CSM remains debated with varying opinions favoring anterior versus posterior surgical approaches. We present an analysis of a prospective observational multicenter study examining outcomes of surgical treatment for CSM.Methods
A total of 278 subjects from 12 sites in North America received anterior/posterior or combined surgery at the discretion of the surgeon. This study focused on subjects who had either anterior or posterior surgery (n = 264, follow-up rate, 87%). Outcome measures included the modified Japanese Orthopedic Assessment scale, the Nurick scale, the Neck Disability Index, and the Short-Form 36 (SF-36) Health Survey version 2 Physical and Mental Component Scores.Results
One hundred and sixty-nine patients were treated anteriorly and 95 underwent posterior surgery. Anterior surgical cases were younger and had less severe myelopathy as assessed by mJOA and Nurick scores. There were no baseline differences in Neck Disability Index or SF-36 between the anterior and posterior cases. Improvement in the mJOA was significantly lower in the anterior group than posterior group (2.47 vs. 3.62, respectively, P < 0.01), although the groups started at different levels of baseline impairment. The extent of improvement in the Nurick Scale, Neck Disability Index, SF-36 version 2 Physical Component Score, and SF-36 version 2 Mental Component Score did not differ between the groups.Conclusion
Patients with CSM show significant improvements in several health-related outcome measures with either anterior or posterior surgery. Importantly, patients treated with anterior techniques were younger, with less severe impairment and more focal pathology. We demonstrate for the first time that, when patient and disease factors are controlled for, anterior and posterior surgical techniques have equivalent efficacy in the treatment of CSM.Level of evidence
3.Item Open Access Effect of type II odontoid fracture nonunion on outcome among elderly patients treated without surgery: based on the AOSpine North America geriatric odontoid fracture study.(Spine, 2013-12) Smith, Justin S; Kepler, Christopher K; Kopjar, Branko; Harrop, James S; Arnold, Paul; Chapman, Jens R; Fehlings, Michael G; Vaccaro, Alexander R; Shaffrey, Christopher IStudy design
Subgroup analysis of a prospective multicenter study.Objective
Outcome analysis of nonoperatively treated elderly patients with type II odontoid fractures, including assessment of consequence of a fracture nonunion.Summary of background data
Odontoid fractures are among the most common fractures in the elderly, and controversy exists regarding treatment.Methods
Subgroup analysis of a prospective multicenter study of elderly patients (≥65 yr) with type II odontoid fracture. Neck Disability Index and Short-Form 36 (SF-36) version 2 were collected at baseline and 6 and 12 months. Fifty-eight (36.5%) of the 159 patients were treated nonoperatively.Results
Of the 58 patients initially treated nonoperatively, 8 died within 90 days and were excluded. Of the remaining 50 patients, 11 (22.0%) developed nonunion, with 7 (63.6%) requiring surgery. Four of the 39 (10.3%) patients classified as having "successful union" required surgery due to late fracture displacement. Thus, 15 (30.0%) patients developed primary or secondary nonunion and 11 (22.0%) required surgery. The overall 12-month mortality was 14.0% (nonunion = 2, union = 5; P= 0.6407). For union and nonunion groups, Neck Disability Index and SF-36 version 2 declined significantly at 12 months compared with preinjury values (P< 0.05), except for SF-36 version 2 Physical Functioning (P= 0.1370). There were no significant differences in outcome parameters based on union status at 12 months (P> 0.05); however, it is important to emphasize that the 12-month outcomes for the nonunion patients reflect the status of the patient after delayed surgical treatment in the majority of these cases.Conclusion
Nonoperative treatment for type II odontoid fracture in the elderly has high rates of nonunion and mortality. Patients with nonunion did not report worse outcomes compared with those who achieved union at 12 months; however, the majority of patients with nonunion required delayed surgical treatment. These findings may prove useful for patients who are not surgical candidates or elect for nonoperative treatment.Level of evidence
2.Item Open Access Efficacy and safety of surgical decompression in patients with cervical spondylotic myelopathy: results of the AOSpine North America prospective multi-center study.(The Journal of bone and joint surgery. American volume, 2013-09) Fehlings, Michael G; Wilson, Jefferson R; Kopjar, Branko; Yoon, Sangwook Tim; Arnold, Paul M; Massicotte, Eric M; Vaccaro, Alexander R; Brodke, Darrel S; Shaffrey, Christopher I; Smith, Justin S; Woodard, Eric J; Banco, Robert J; Chapman, Jens R; Janssen, Michael E; Bono, Christopher M; Sasso, Rick C; Dekutoski, Mark B; Gokaslan, Ziya LBackground
Cervical spondylotic myelopathy is the leading cause of spinal cord dysfunction worldwide. The objective of this study was to evaluate the impact of surgical decompression on functional, quality-of-life, and disability outcomes at one year after surgery in a large cohort of patients with this condition.Methods
Adult patients with symptomatic cervical spondylotic myelopathy and magnetic resonance imaging evidence of spinal cord compression were enrolled at twelve North American centers from 2005 to 2007. At enrollment, the myelopathy was categorized as mild (modified Japanese Orthopaedic Association [mJOA] score ≥ 15), moderate (mJOA = 12 to 14), or severe (mJOA < 12). Patients were followed prospectively for one year, at which point the outcomes of interest included the mJOA score, Nurick grade, Neck Disability Index (NDI), and Short Form-36 version 2 (SF-36v2). All outcomes at one year were compared with the preoperative values with use of univariate paired statistics. Outcomes were also compared among the severity classes with use of one-way analysis of variance. Finally, a multivariate analysis that adjusted for baseline differences among the severity groups was performed. Treatment-related complication data were collected and the overall complication rate was calculated.Results
Eighty-five (30.6%) of the 278 enrolled patients had mild cervical spondylotic myelopathy, 110 (39.6%) had moderate disease, and 83 (29.9%) had severe disease preoperatively. One-year follow-up data were available for 222 (85.4%) of 260 patients. There was a significant improvement from baseline to one year postoperatively (p < 0.05) in the mJOA score, Nurick grade, NDI score, and all SF-36v2 health dimensions (including the mental and physical health composite scores) except general health. With the exception of the change in the mJOA, the degree of improvement did not depend on the severity of the preoperative symptoms. These results remained unchanged after adjusting for relevant confounders in the multivariate analysis. Fifty-two patients experienced complications (prevalence, 18.7%), with no significant differences among the severity groups.Conclusions
Surgical decompression for the treatment of cervical spondylotic myelopathy was associated with improvement in functional, disability-related, and quality-of-life outcomes at one year of follow-up for all disease severity categories. Furthermore, complication rates observed in the study were commensurate with those in previously reported cervical spondylotic myelopathy series.Item Open Access Functional and quality-of-life outcomes in geriatric patients with type-II dens fracture.(The Journal of bone and joint surgery. American volume, 2013-04) Vaccaro, Alexander R; Kepler, Christopher K; Kopjar, Branko; Chapman, Jens; Shaffrey, Christopher; Arnold, Paul; Gokaslan, Ziya; Brodke, Darrel; France, John; Dekutoski, Mark; Sasso, Rick; Yoon, S Tim; Bono, Christopher; Harrop, James; Fehlings, Michael GBackground
Dens fractures are relatively common in the elderly. The treatment of Type-II dens fractures remains controversial. The aim of this multicenter prospective cohort study was to compare outcomes (assessed with use of validated clinical measures) and complications of nonsurgical and surgical treatment of Type-II dens fractures in patients sixty-five years of age or older.Methods
One hundred and fifty-nine patients with a Type-II dens fracture were enrolled in a multicenter prospective study. Subjects were treated either surgically (n = 101) or nonsurgically (n = 58) as determined by the treatment preferences of the treating physicians and the patients. The subjects were followed at six and twelve months with validated outcome measures, including the Neck Disability Index (NDI) and Short Form-36v2 (SF-36v2). Treatment complications were prospectively recorded. Statistical analysis was performed to compare outcome measures before and after adjustment for confounding variables.Results
The two groups were similar with regard to baseline characteristics. The most common surgical treatment was posterior C1-C2 arthrodesis (eighty of 101, or 79%) while the most common nonsurgical treatment was immobilization with use of a hard collar (forty-seven of fifty-eight, or 81%). The overall mortality rate was 18% over the twelve-month follow-up period. At twelve months, the NDI had increased (worsened) by 14.7 points in the nonsurgical cohort (p < 0.0001) compared with a nonsignificant increase (worsening) of 5.7 points in the surgical group (p = 0.0555). The surgical group had significantly better outcomes as measured by the NDI and SF-36v2 Bodily Pain dimension compared with the nonsurgical group, and these differences persisted after adjustment. There was no difference in the overall rate of complications, but the surgical group had a significantly lower rate of nonunion (5% versus 21% in the nonsurgical group; p = 0.0033). Mortality was higher in the nonsurgical group compared with the surgical group (annual mortality rates of 26% and 14%, respectively; p = 0.059).Conclusions
We demonstrated a significant benefit with surgical treatment of dens fractures as measured by the NDI, a disease-specific functional outcome measure. As a result of the nonrandomized nature of the study, the results are vulnerable to the effects of possible residual confounding. We recommend that elderly patients with a Type-II dens fracture who are healthy enough for general anesthesia be considered for surgical stabilization to improve functional outcome as well as the union and fusion rates.Item Open Access In response.(Spine, 2014-07) Fehlings, Michael G; Barry, Sean; Kopjar, Branko; Yoon, Sangwook Tim; Arnold, Paul; Massicotte, Eric M; Vaccaro, Alexander; Brodke, Darrel S; Shaffrey, Christopher; Smith, Justin S; Woodard, Eric; Banco, Robert J; Chapman, Jens; Janssen, Michael; Bono, Christopher; Sasso, Rick; Dekutoski, Mark; Gokaslan, Ziya LItem Open Access Mild diabetes is not a contraindication for surgical decompression in cervical spondylotic myelopathy: results of the AOSpine North America multicenter prospective study (CSM).(The spine journal : official journal of the North American Spine Society, 2014-01) Arnold, Paul M; Fehlings, Michael G; Kopjar, Branko; Yoon, Sangwook Tim; Massicotte, Eric M; Vaccaro, Alexander R; Brodke, Darrel S; Shaffrey, Christopher I; Smith, Justin S; Woodard, Eric J; Banco, Robert J; Chapman, Jens R; Janssen, Michael E; Bono, Christopher M; Sasso, Rick C; Dekutoski, Mark B; Gokaslan, Ziya LBackground context
Cervical spondylotic myelopathy (CSM) is a chronic spinal cord disease and can lead to progressive or stepwise neurologic decline. Several factors may influence this process, including extent of spinal cord compression, duration of symptoms, and medical comorbidities. Diabetes is a systemic disease that can impact multiple organ systems, including the central and peripheral nervous systems. There has been little information regarding the effect of diabetes on patients with coexistent CSM.Purpose
To provide empirical data regarding the effect of diabetes on treatment outcomes in patients who underwent surgical decompression for coexistent CSM.Study design/setting
Large prospective multicenter cohort study of patients with and without diabetes who underwent decompressive surgery for CSM.Patient sample
Two hundred thirty-six patients without and 42 patients with diabetes were enrolled. Of these, 37 were mild cases and five were moderate cases. Four required insulin. There were no severe cases associated with end-organ damage.Outcome measures
Self-report measures include Neck Disability Index and version 2 of 36-Item Short Form Health Survey (SF-36v2), and functional measures include modified Japanese Orthopedic Association (mJOA) score and Nurick grade.Methods
We compared presurgery symptoms and treatment outcomes between patients with and without diabetes using univariate and multivariate models, adjusting for demographics and comorbidities.Results
Diabetic patients were older, less likely to smoke, and more likely to be on social security disability insurance. Patients with diabetes presented with a worse Nurick grade, but there were no differences in mJOA and SF-36v2 at presentation. Overall, there was a significant improvement in all outcome parameters at 12 and 24 months. There was no difference in the level of improvement between the patients with and without diabetes, except in the SF-36v2 Physical Functioning, in which diabetic patients experienced significantly less improvement. There were no differences in surgical complication rates between diabetic patients and nondiabetic patients.Conclusions
Except for a worse Nurick grade, diabetes does not seem to affect severity of symptoms at presentation for surgery. More importantly, with the exception of the SF-36v2 Physical Functioning scores, outcomes of surgical treatment are similar in patients with diabetes and without diabetes. Surgical decompression is effective and should be offered to patients with diabetes who have symptomatic CSM and are appropriate surgical candidates.Item Open Access Novel Method Using Baseline Normalization and Area Under the Curve to Evaluate Differences in Outcome Between Treatment Groups and Application to Patients With Cervical Spondylotic Myelopathy Undergoing Anterior Versus Posterior Surgery.(Spine, 2015-12) Liu, Shian; Tetreault, Lindsay; Fehlings, Michael G; Challier, Vincent; Smith, Justin S; Shaffrey, Christopher I; Arnold, Paul M; Scheer, Justin K; Chapman, Jens R; Kopjar, Branko; Protopsaltis, Themistocles S; Lafage, Virginie; Schwab, Frank; Massicotte, Eric M; Yoon, Sangwook T; Ames, Christopher PRetrospective review of a prospective database.To describe a novel method that uses baseline normalization and area under the curve (AUC) to compare surgical outcomes between patients surgically treated anteriorly versus posteriorly for cervical spondylotic myelopathy (CSM).It is important to control for baseline characteristics, especially disease severity, when evaluating differences in outcomes between 2 treatment groups. However, current methods of reporting outcomes are limited perhaps diminish the health impact of the entire postoperative recovery experience.In the prospective, multicenter AO Spine North America CSM database, 147 patients had complete modified Japanese Orthopaedic Association (mJOA) data at baseline and at 6-, 12-, and 24-months postoperatively and were either treated anteriorly (n = 94) or posteriorly (n = 53). Each patient's follow-up mJOA scores were normalized by dividing them by the patient's baseline value. A graph was then plotted with the time point on the x-axis and the normalized score or "recovery index" on the y-axis. The AUC was calculated and then compared between the anterior and posterior surgical approach groups.The non-normalized recovery profile of the anterior group was better than that of the posterior group, as the patients treated anteriorly had less functional impairment at baseline. After normalization, patients in the anterior and posterior group had similar recovery indices and AUCs at 6-months following surgery. At 24-months, patients treated posteriorly had a significantly higher recovery index (1.32) and a larger AUC (16.3) than those treated anteriorly (1.11, 14.5, P = 0.004 and P = 0.006, respectively).This is the first study to apply AUC analysis to patients with CSM. In surgical patients with CSM, those treated anteriorly achieved a higher mJOA score at all time points than those treated posteriorly. The recovery indices, however, were not significantly different between approach groups at 6 months.3.Item Open Access Perioperative and delayed complications associated with the surgical treatment of cervical spondylotic myelopathy based on 302 patients from the AOSpine North America Cervical Spondylotic Myelopathy Study.(Journal of neurosurgery. Spine, 2012-05) Fehlings, Michael G; Smith, Justin S; Kopjar, Branko; Arnold, Paul M; Yoon, S Tim; Vaccaro, Alexander R; Brodke, Darrel S; Janssen, Michael E; Chapman, Jens R; Sasso, Rick C; Woodard, Eric J; Banco, Robert J; Massicotte, Eric M; Dekutoski, Mark B; Gokaslan, Ziya L; Bono, Christopher M; Shaffrey, Christopher IObject
Rates of complications associated with the surgical treatment of cervical spondylotic myelopathy (CSM) are not clear. Appreciating these risks is important for patient counseling and quality improvement. The authors sought to assess the rates of and risk factors associated with perioperative and delayed complications associated with the surgical treatment of CSM.Methods
Data from the AOSpine North America Cervical Spondylotic Myelopathy Study, a prospective, multicenter study, were analyzed. Outcomes data, including adverse events, were collected in a standardized manner and externally monitored. Rates of perioperative complications (within 30 days of surgery) and delayed complications (31 days to 2 years following surgery) were tabulated and stratified based on clinical factors.Results
The study enrolled 302 patients (mean age 57 years, range 29-86) years. Of 332 reported adverse events, 73 were classified as perioperative complications (25 major and 48 minor) in 47 patients (overall perioperative complication rate of 15.6%). The most common perioperative complications included minor cardiopulmonary events (3.0%), dysphagia (3.0%), and superficial wound infection (2.3%). Perioperative worsening of myelopathy was reported in 4 patients (1.3%). Based on 275 patients who completed 2 years of follow-up, there were 14 delayed complications (8 minor, 6 major) in 12 patients, for an overall delayed complication rate of 4.4%. Of patients treated with anterior-only (n = 176), posterior-only (n = 107), and combined anterior-posterior (n = 19) procedures, 11%, 19%, and 37%, respectively, had 1 or more perioperative complications. Compared with anterior-only approaches, posterior-only approaches had a higher rate of wound infection (0.6% vs 4.7%, p = 0.030). Dysphagia was more common with combined anterior-posterior procedures (21.1%) compared with anterior-only procedures (2.3%) or posterior-only procedures (0.9%) (p < 0.001). The incidence of C-5 radiculopathy was not associated with the surgical approach (p = 0.8). The occurrence of perioperative complications was associated with increased age (p = 0.006), combined anterior-posterior procedures (p = 0.016), increased operative time (p = 0.009), and increased operative blood loss (p = 0.005), but it was not associated with comorbidity score, body mass index, modified Japanese Orthopaedic Association score, smoking status, anterior-only versus posterior-only approach, or specific procedures. Multivariate analysis of factors associated with minor or major complications identified age (OR 1.029, 95% CI 1.002-1.057, p = 0.035) and operative time (OR 1.005, 95% CI 1.002-1.008, p = 0.001). Multivariate analysis of factors associated with major complications identified age (OR 1.054, 95% CI 1.015-1.094, p = 0.006) and combined anterior-posterior procedures (OR 5.297, 95% CI 1.626-17.256, p = 0.006).Conclusions
For the surgical treatment of CSM, the vast majority of complications were treatable and without long-term impact. Multivariate factors associated with an increased risk of complications include greater age, increased operative time, and use of combined anterior-posterior procedures.Item Open Access Safety and efficacy of riluzole in patients undergoing decompressive surgery for degenerative cervical myelopathy (CSM-Protect): a multicentre, double-blind, placebo-controlled, randomised, phase 3 trial.(The Lancet. Neurology, 2021-02) Fehlings, Michael G; Badhiwala, Jetan H; Ahn, Henry; Farhadi, H Francis; Shaffrey, Christopher I; Nassr, Ahmad; Mummaneni, Praveen; Arnold, Paul M; Jacobs, W Bradley; Riew, K Daniel; Kelly, Michael; Brodke, Darrel S; Vaccaro, Alexander R; Hilibrand, Alan S; Wilson, Jason; Harrop, James S; Yoon, S Tim; Kim, Kee D; Fourney, Daryl R; Santaguida, Carlo; Massicotte, Eric M; Kopjar, BrankoBackground
Degenerative cervical myelopathy represents the most common form of non-traumatic spinal cord injury. This trial investigated whether riluzole enhances outcomes in patients undergoing decompression surgery for degenerative cervical myelopathy.Methods
This multicentre, double-blind, placebo-controlled, randomised, phase 3 trial was done at 16 university-affiliated centres in Canada and the USA. Patients with moderate-to-severe degenerative cervical myelopathy aged 18-80 years, who had a modified Japanese Orthopaedic Association (mJOA) score of 8-14, were eligible. Patients were randomly assigned (1:1) to receive either oral riluzole (50 mg twice a day for 14 days before surgery and then for 28 days after surgery) or placebo. Randomisation was done using permuted blocks stratified by study site. Patients, physicians, and outcome assessors remained masked to treatment group allocation. The primary endpoint was change in mJOA score from baseline to 6 months in the intention-to-treat (ITT) population, defined as all individuals who underwent randomisation and surgical decompression. Adverse events were analysed in the modified intention-to-treat (mITT) population, defined as all patients who underwent randomisation, including those who did not ultimately undergo surgical decompression. This study is registered with ClinicalTrials.gov, NCT01257828.Findings
From Jan 31, 2012, to May 16, 2017, 408 patients were screened. Of those screened, 300 were eligible (mITT population); 290 patients underwent decompression surgery (ITT population) and received either riluzole (n=141) or placebo (n=149). There was no difference between the riluzole and placebo groups in the primary endpoint of change in mJOA score at 6-month follow-up: 2·45 points (95% CI 2·08 to 2·82 points) versus 2·83 points (2·47 to 3·19), difference -0·38 points (-0·90 to 0·13; p=0·14). The most common adverse events were neck or arm or shoulder pain, arm paraesthesia, dysphagia, and worsening of myelopathy. There were 43 serious adverse events in 33 (22%) of 147 patients in the riluzole group and 34 serious adverse events in 29 (19%) of 153 patients in the placebo group. The most frequent severe adverse events were osteoarthrosis of non-spinal joints, worsening of myelopathy, and wound complications.Interpretation
In this trial, adjuvant treatment for 6 weeks perioperatively with riluzole did not improve functional recovery beyond decompressive surgery in patients with moderate-to-severe degenerative cervical myelopathy. Whether riluzole has other benefits in this patient population merits further study.Funding
AOSpine North America.Item Open Access The AOSpine North America Geriatric Odontoid Fracture Mortality Study: a retrospective review of mortality outcomes for operative versus nonoperative treatment of 322 patients with long-term follow-up.(Spine, 2013-06) Chapman, Jens; Smith, Justin S; Kopjar, Branko; Vaccaro, Alexander R; Arnold, Paul; Shaffrey, Christopher I; Fehlings, Michael GSTUDY DESIGN: Retrospective, multicenter cohort study. OBJECTIVE: Assess for differences in short- and long-term mortality between operative and nonoperative treatment for elderly patients with type II odontoid fractures. SUMMARY OF BACKGROUND DATA: There is controversy regarding whether operative or nonoperative management is the best treatment for elderly patients with type II odontoid fractures. METHODS: This is a retrospective study of consecutive patients aged 65 years or older with type II odontoid fracture from 3 level I trauma centers from 2003-2009. Demographics, comorbidities, and treatment were abstracted from medical records. Mortality outcomes were obtained from medical records and a public database. Hazard ratios (HRs) and 95% confidence intervals (CI) were calculated. RESULTS: A total of 322 patients were included (mean age, 81.8 yr; range, 65.0-101.5 yr). Compared with patients treated nonoperatively (n = 157), patients treated operatively (n = 165) were slightly younger (80.4 vs. 83.2 yr, P = 0.0014), had a longer hospital (15.0 vs. 7.4 d, P < 0.001) and intensive care unit (1.5 vs. 1.1 d, P = 0.008) stay, and were more likely to receive a feeding tube (18% vs. 5%, P = 0.0003). Operative and nonoperative treatment groups had similar sex distribution (P = 0.94) and Charlson comorbidity index (P = 0.11). Within 30 days of presentation, 14% of patients died, and at maximal follow-up (average = 2.05 yr; range = 0 d-7.02 yr), 44% had died. On multivariate analysis, nonoperative treatment was associated with higher 30-day mortality (HR = 3.00, 95% CI = 1.51-5.94, P = 0.0017), after adjusting for age (HR = 1.10, 95% CI = 1.05-1.14; P < 0.0001), male sex (P = 0.69), and Charlson comorbidity index (P = 0.16). At maximal follow-up, there was a trend toward higher mortality associated with nonoperative treatment (HR = 1.35, 95% CI = 0.97-1.89, P = 0.079), after adjusting for age (HR = 1.07, 95% CI = 1.05-1.10; P < 0.0001), male sex (HR = 1.55, 95% CI = 1.10-2.16; P = 0.012), and Charlson comorbidity index (HR = 1.28, 95% CI = 1.16-1.40; P < 0.0001). CONCLUSION: Surgical treatment of type II odontoid fracture in this elderly population did not negatively impact survival, even after adjusting for age, sex, and comorbidities. The data suggest a significant 30-day survival advantage and a trend toward improved longer-term survival for operatively treated over nonoperatively treated patients. LEVEL OF EVIDENCE: 4.