High preoperative expectations and postoperative fulfillment of expectations two years after decompression alone and decompression plus fusion for lumbar degenerative spondylolisthesis

Combining preoperative expectations and postoperative met expectations to predict patient-reported outcomes after knee surgery

Introduction

Both preoperative expectations and postoperative met expectations can independently influence patient-reported outcomes (PROs), however, their combined effect on PROs is not well understood. This study aimed to determine the prognostic significance of categorizing non-arthroplasty knee surgery patients into clusters based on both preoperative expectations and postoperative met expectations.

Methods

638 patients who underwent non-arthroplasty knee surgery from June 2015 to May 2021 at a single academic institution were analyzed. Patients were grouped based on both preoperative expectations and two-year postoperative met expectations scores using cluster analysis. Four distinct expectations cluster groups were formed: high preoperative-high met expectations (HIGH-HIGH), low preoperative-high met expectations (LOW-HIGH), high preoperative-low met expectations (HIGH-LOW), and low preoperative-low met expectations (LOW-LOW). Socioeconomic data and PROs were compared based on cluster group, and logistic regression was performed to determine the likelihood of achieving a patient-perceived "completely better" status based on cluster group.

Results

Patients with high met expectations, regardless of preoperative expectations, reported better two-year PROs compared to patients with low met expectations. Patients with high preoperative expectations achieved better outcomes only when those expectations were met postoperatively. Low preoperative expectations did not preclude patients from achieving good outcomes, as long as those expectations were met. The HIGH-HIGH group had increased odds of achieving completely better status compared to the LOW-HIGH group (OR = 1.68, p = .02), HIGH-LOW group (OR = 16.69, p < .001), and LOW-LOW group (OR = 5.17, p < .001). The HIGH-LOW group had decreased odds of achieving completely better status compared to the LOW-LOW group (OR = .31, p = .01).

Conclusion

Met expectations may be a stronger predictor of postoperative outcomes than preoperative expectations in non-arthroplasty knee surgery. This study highlights the importance of setting realistic preoperative expectations and focusing on achieving expectations postoperatively. These findings offer valuable insights for clinicians to manage patient expectations effectively based on individual characteristics and expected treatment outcomes.

Preoperative determinants of postoperative expectation fulfillment following elective lumbar spine surgery: an observational study from the Canadian Spine Outcome Research Network (CSORN)

BACKGROUND CONTEXT

Preoperative patient factors determining expectation fulfillment from elective lumbar surgeries are poorly defined.

PURPOSE

To identify preoperative factors associated with the levels of expectation fulfillment following elective lumbar spine surgery.

STUDY DESIGN/ SETTING

This retrospective cohort study used the Canadian Spine Outcome Research Network (CSORN) registry data with participants enrolled between January 2015 and December 2020. The registry prospectively enrolled surgical patients to treat spinal disorders from twenty-three sites. Participating patients completed preoperative and follow-up questionnaires, including information on surgery expectations. Patients recorded their levels of expectation fulfillment on a Likert scale of 1 to 5, with responses ranging from Completely met (5) to Not applicable (1) in 7 expectation dimensions.

PATIENT SAMPLE

Consecutive patients with 4 lumbar conditions (spinal stenosis, disc herniation, degenerative disc disease, or degenerative spondylolisthesis) and those with complete 1-year follow-up questionnaires were included. Patients treated for thoracic or cervical pathologies and nonelective lumbar conditions were excluded. A total of 5389 patients who underwent surgery and completed 1-year follow-up questionnaires out of 6971 eligible patients were included. Patients' socio-demographics, lifestyle, health status, and clinical factors were examined.

OUTCOME MEASURES

The primary outcome was the association between expectation fulfillment and preoperative patient factors.

METHODS

Patient factors were described for the expectation fulfillment categories using descriptive statistics. Bivariable and multivariable associations between patient factors and expectation fulfillment were estimated with ordinal logistic regression models. Point estimates represented as odd ratios, and 95% CIs were reported.

RESULTS

The mean age of the participants was 59.5 years, with 49.8% (2683) of them being women. Unmet expectations ranged from 6.7% to 25.7%, with improvement in general physical capacity being the most important expectation fulfilled from surgery for 20% of patients. Factors such as longer symptom duration (OR: 0.74; 95% CI: 0.63-0.86), previous lumbar spine surgery (OR: 0.63; 95% CI: 0.46, 0.89), and reoperations (OR: 0.36; 95% CI: 0.2, 0.63) were associated with higher unmet expectations in the leg pain reduction dimension. Similar results were noted across all other expectation dimensions.

CONCLUSION

Utilizing information on the preoperative factors in presurgical consultations can improve patient satisfaction and expectations from surgery.

The Influence of Previous Joint Arthroplasty on Fulfillment of Patients' Expectations of Subsequent Lumbar Surgery

INTRODUCTION

Hip, knee, and lumbar spine surgeries are prevalent with arthroplasty often preceding lumbar surgery. The objective of this analysis was to ascertain whether previous arthroplasty was associated with patients' postlumbar surgery fulfillment of expectations.

METHODS

Identical systematically acquired data were pooled from 3 prospective studies that included assessments of preoperative expectations of lumbar surgery and 2-year postoperative assessment of fulfillment of expectations using a valid survey with points assigned for amount of improvement expected for symptoms and function. The proportion of expectations fulfilled was defined as total points for improvement received postoperatively divided by total points for improvement expected preoperatively (range 0 [no expectations fulfilled] to >1 [expectations surpassed]). Enrollment data included the expectations survey, demographic/clinical characteristics, Oswestry Disability Index (ODI) scores, and previous hip/knee arthroplasty. Postoperative data included follow-up expectations survey, ODI scores, and any spine complications. The proportion was the dependent variable in multivariable linear regression with demographic/clinical independent variables.

RESULTS

1137 patients were included (mean age 59 years, 51% male); 993 (87%) did not have previous arthroplasty, and 144 (13%) had arthroplasty (51 hip only, 77 knee only, 16 both hip/knee). Patients with any arthroplasty had similarly high expectations compared with patients with no arthroplasty but lower proportion of expectations fulfilled (0.69 versus 0.76, P = 0.03). In multivariable analysis, variables associated with a lower proportion of expectations fulfilled were greater preoperative expectations ( P < 0.0001), not working ( P < 0.0001), positive depression screen ( P = 0.0002), previous lumbar surgery ( P < 0.0001), previous arthroplasty ( P = 0.03), surgery on ≥3 vertebrae ( P = 0.007), less preoperative-to-postoperative ODI improvement ( P < 0.0001), and postoperative complications ( P < 0.0001).

CONCLUSIONS

After accounting for a spectrum of highly associated covariates, patients with previous arthroplasty still had less fulfillment of expectations of subsequent lumbar surgery. For patients with previous arthroplasty, surgeons should discuss potential differences between arthroplasty and lumbar surgery during preoperative evaluations and during shared postoperative assessments of the outcome.

Previous Hip or Knee Arthroplasty is Associated With Less Favorable Patient-reported Outcomes of Lumbar Surgery

STUDY DESIGN

Review of cohort studies.

OBJECTIVE

To ascertain if previous hip (THA) or knee (TKA) arthroplasty was associated with patients' outcomes assessments of subsequent lumbar surgery, specifically overall satisfaction, less disability due to pain, and an affective appraisal reflecting emotional assessment of results.

BACKGROUND

Hip, knee, and lumbar symptoms often co-exist and increasingly are managed with surgery. Whether previous total joint arthroplasty (TJA) impacts patients' perspectives of results of subsequent lumbar surgery is not known.

METHODS

Identical and systematically acquired preoperative and postoperative data from 3 studies assessing psychosocial characteristics and outcomes of lumbar surgery were pooled. Data obtained during interviews included preoperative demographic and clinical variables and 2-year postoperative global overall assessment (very satisfied/satisfied, neither, dissatisfied/very dissatisfied) and global affective assessment (delighted/pleased, mostly satisfied/mixed/mostly dissatisfied, unhappy/terrible). Patients completed the ODI and preoperative to postoperative change was analyzed according to an MCID (15 points). At 2 years patients also reported any untoward events since surgery (ie, fracture, infection, or repeat lumbar surgery). Associations with outcomes were assessed with multivariable logistic ordinal regression controlling for untoward events. Type of arthroplasty was evaluated in subanalyses.

RESULTS

Among 1227 patients (mean: 59 y, 50% women), 12% had arthroplasty (+TJA) and 88% did not (-TJA). In multivariable analysis, +TJA was associated with less global satisfaction (OR: 1.9, CI: 1.3-2.7, P=0.0007), worse global affective assessment (OR: 1.6, CI: 1.1-2.2, P=0.009), and not meeting MCID15 (OR: 1.5, CI: 1.0-2.3, P=0.05). Covariables associated with less favorable outcomes were not working, positive depression screen, and prior lumbar surgery. Compared with -TJA, patients with THA had worse affective assessments and patients with TKA had less satisfaction and were less likely to meet MCID15.

CONCLUSIONS

Previous hip or knee arthroplasty was associated with less favorable patient-reported outcomes of lumbar surgery. Surgeons and patients should discuss differences between procedures preoperatively and during shared postoperative outcome assessment.

LEVEL OF EVIDENCE

Level II.

Expectations in patients undergoing spine surgery are high and unmet

BACKGROUND CONTEXT

Defining success in spine surgery lacks a standardized approach, and all existing concepts are based on registrations after surgery.

PURPOSE

To examine patients' expectations before spine surgery assessed by a modified Oswestry Disability Index (ODI) and Numeric Rating Scale (NRS). The authors asked: how do the expectations align with actual outcomes and can a patient's individual expectations be used as a success criterion in itself?

STUDY DESIGN /SETTING

Prospective single-center study.

PATIENT SAMPLE

Patients scheduled for spine surgery at Akershus University Hospital (AHUS) were included in the study. They underwent 1 of 3 procedures: decompression for spinal stenosis, disc removal for lumbar disc herniation, or spinal fusion for degenerative disc disease.

OUTCOME MEASURES

Modified and standard version of ODI and NRS (back and leg pain).

METHODS

Preoperatively, the patients were given a modified ODI and NRS questionnaire in which they were asked to register the minimum acceptable functional impairment and pain they anticipated to have postsurgery. The patients' expectations were compared with 3-and 12-month follow-up data from the Norwegian Registry for Spine Surgery (NORspine) with ODI, NRS and Global Perceived Effect (GPE) scale. We used simple descriptive statistics.

RESULTS

A total of 93 patients completed the pre-op questionnaire. Of these, 65 responded to the 3-month follow-up and 53 at 12-month follow-up. The mean (95%CI) ODI before surgery was 38.3 (34.2-42.3), the mean (95% CI) preoperative NRS back pain was 6.34 (5.81-6.88), and leg pain was 6.67 (6.08-7.26). The patients expected a mean (95% CI) ODI of 10.5 (7.5-13.5), mean (95%CI) NRS back pain of 2.5 (2.1-3.0), and NRS leg pain of 1.8 (1.5-2.2). The actual clinical outcome after 12 months were a mean (95% CI) ODI of 21.7 (17.0-26.5), NRS back pain of 3.4 (2.8-4.1), and leg pain of 2.8 (2.0-3.5). Only 12 (30.8%) patients achieved their expected ODI, while 26 (65.0%) classified themselves as significantly better according to GPE.

CONCLUSIONS

Patients seem to have high expectations before spine surgery, and the expectations may exceed the clinical outcome. Only 30.8% had their ODI expectations met, but perceived benefit was higher. High expectations may be due to inadequate preoperative information and/or the unsuitability of ODI for capturing expectations.

Examining the Role of Paraspinal Musculature in Postoperative Disability After Lumbar Fusion Surgery for Degenerative Spondylolisthesis

STUDY DESIGN

Retrospective analysis of prospectively enrolled patients.

OBJECTIVE

To evaluate the relationship between paraspinal muscle (PM) atrophy and Oswestry Disability Index (ODI) improvement after spinal fusion surgery for degenerative lumbar spondylolisthesis.

BACKGROUND

Atrophy of the PM is linked to multiple spinal conditions, sagittal malalignment, and increased postoperative complications. However, only limited evidence for the effect on patient-reported outcomes exists.

METHODS

Patients with degenerative lumbar spondylolisthesis undergoing decompression and fusion surgery were analyzed. Patients with missing follow-up, no imaging, or inadequate image quality were excluded. The ODI was assessed preoperatively and two years postoperatively. A cross-sectional area of the PM was measured on a T2-weighted magnetic resonance imaging sequence at the upper endplate of L4. On the basis of the literature, a 10-point improvement cutoff was defined as the minimum clinically important difference. Patients with a baseline ODI below the minimum clinically important difference were excluded. Logistic regression was used to calculate the association between fatty infiltration (FI) of the PM and improvement in ODI, adjusted for age, sex, and body mass index.

RESULTS

A total of 133 patients were included in the final analysis, with only two lost to follow-up. The median age was 68 years (IQR 62-73). The median preoperative ODI was 23 (IQR 17-28), and 76.7% of patients showed improvement in their ODI score by at least 10 points. In the multivariable regression, FI of the erector spinae and multifidus increased the risk of not achieving clinically relevant ODI improvement ( P =0.01 and <0.001, respectively). No significant association was found for the psoas muscle ( P =0.158).

CONCLUSIONS

This study demonstrates that FI of the erector spinae and multifidus is significantly associated with less likelihood of clinically relevant ODI improvement after decompression and fusion. Further research is needed to assess the effect of interventions.

Association Between Osteoarthritis Burden and Intervertebral Disk Degeneration in Patients Undergoing Lumbar Spine Surgery for Degenerative Lumbar Spondylolisthesis

STUDY DESIGN

A retrospective analysis of prospectively collected data.

OBJECTIVE

To assess the association between intervertebral disk degeneration and hip and knee osteoarthritis (OA) in patients with degenerative lumbar spondylolisthesis.

BACKGROUND

The co-occurrence of hip OA and degenerative spinal pathologies was first described as the "hip-spine syndrome" and has also been observed in knee OA. It remains unclear whether both pathologies share an underlying connection beyond demographic factors.

MATERIALS AND METHODS

Intervertebral disk degeneration was classified by the Pfirrmann Classification and intervertebral vacuum phenomenon. Intervertebral vacuum phenomenon was classified into mild (1 point), moderate (2 points), and severe (3 points) at each level and combined into a lumbar vacuum score (0-15 points). Similarly, a lumbar Pfirrmann grade was calculated (5-25 points). Patients with previous hip or knee replacement surgery were classified as having an OA burden. We used multivariable regression to assess the association between OA and disk degeneration, adjusted for age, body mass index, and sex.

RESULTS

A total of 246 patients (58.9% female) were included in the final analysis. Of these, 22.3% had OA burden. The multivariable linear regression showed an independent association between OA burden and lumbar vacuum (β = 2.1, P <0.001) and Pfirrmann grade (β = 2.6, P <0.001). Representing a 2.1 points higher lumbar vacuum and 2.6 points higher lumbar Pfirrmann grade after accounting for demographic differences.

CONCLUSIONS

Our study showed that OA burden was independently associated with the severity of the intervertebral disk degeneration of the lumbar spine. These findings give further weight to a shared pathology of OA of large joints and degenerative processes of the lumbar spine.

LEVEL OF EVIDENCE

3.

Decision-making Algorithm for the Surgical Treatment of Degenerative Lumbar Spondylolisthesis of L4/L5

STUDY DESIGN

A retrospective analysis of prospectively collected data.

OBJECTIVE

To report the decision-making process for decompression alone (DA) and decompression and fusion (DF) at a tertiary orthopedic center and compare the operative outcomes between both groups.

BACKGROUND

Controversy exists around the optimal operative treatment for DLS, either with DF or DA. Although previous studies tried to establish specific indications, clinical decision-making algorithms are needed.

MATERIALS AND METHODS

Patients undergoing spinal surgery for DLS at L4/5 were retrospectively analyzed. A survey of spine surgeons was performed to identify factors influencing surgical decision-making, and their association with the surgical procedure was tested in the clinical data set. We then developed a clinical score based on the statistical analysis and survey results. The predictive capability of the score was tested in the clinical data set with a receiver operating characteristic (ROC) analysis. To evaluate the clinical outcome, two years follow-up postoperative Oswestry Disability Index (ODI), postoperative low back pain (LBP) (Numeric Analog Scale), and patient satisfaction were compared between the DF and DA groups.

RESULTS

A total of 124 patients were included in the analysis; 66 received DF (53.2%) and 58 DA (46.8%). Both groups showed no significant differences in postoperative ODI, LBP, or satisfaction. The degree of spondylolisthesis, facet joint diastasis and effusion, sagittal disbalance, and severity of LBP were identified as the most important factors for deciding on DA or DF. The area under the curve of the decision-making score was 0.84. At a cutoff of three points indicating DF, the accuracy was 80.6%.

CONCLUSIONS

The two-year follow-up data showed that both groups showed similar improvement in ODI after both procedures, validating the respective decision. The developed score shows excellent predictive capabilities for the decision processes of different spine surgeons at a single tertiary center and highlights relevant clinical and radiographic parameters. Further studies are needed to assess the external applicability of these findings.

Association of abdominal aortic calcification and lower back pain in patients with degenerative spondylolisthesis

ABSTRACT

Abdominal aortic calcification (AAC) is hypothesized to lead to ischemic pain of the lower back. This retrospective study aims to identify the relationship between AAC and lower back pain (LBP) in patients with degenerative lumbar spondylolisthesis. Lower back pain was assessed preoperatively and 2 years after surgery using the numeric analogue scale. Abdominal aortic calcification was assessed according to the Kauppila classification and was grouped into no, moderate, and severe. A multivariable regression, adjusted for age, sex, body mass index, hypertension, and smoking status, was used to assess the association between AAC and preoperative/postoperative LBP as well as change in LBP after surgery. A total of 262 patients were included in the final analysis. The multivariable logistic regression demonstrated an increased odds ratio (OR) for preoperative LBP ≥ 4 numeric analogue scale (OR = 9.49, 95% confidence interval [CI]: 2.71-40.59, P < 0.001) and postoperative LBP ≥ 4 (OR = 1.72, 95% CI: 0.92-3.21, P = 0.008) in patients with severe AAC compared with patients with no AAC. Both moderate and severe AAC were associated with reduced improvement in LBP after surgery (moderate AAC: OR = 0.44, 95% CI: 0.22-0.85, P = 0.016; severe AAC: OR = 0.41, 95% CI: 0.2-0.82, P = 0.012). This study demonstrates an independent association between AAC and LBP and reduced improvement after surgery. Evaluation of AAC could play a role in patient education and might be considered part of the differential diagnosis for LBP, although further prospective studies are needed.

Severe Intervertebral Vacuum Phenomenon is Associated With Higher Preoperative Low Back Pain, ODI, and Indication for Fusion in Patients With Degenerative Lumbar Spondylolisthesis

STUDY DESIGN

Retrospective study of prospective collected data.

OBJECTIVE

To analyze the association between intervertebral vacuum phenomenon (IVP) and clinical parameters in patients with degenerative spondylolisthesis.

SUMMARY OF BACKGROUND DATA

IVP is a sign of advanced disc degeneration. The correlation between IVP severity and low back pain in patients with degenerative spondylolisthesis has not been previously analyzed.

METHODS

We retrospectively analyzed patients with degenerative spondylolisthesis who underwent surgery. Vacuum phenomenon was measured on computed tomography scan and classified into mild, moderate, and severe. A lumbar vacuum severity (LVS) scale was developed based on vacuum severity. The associations between IVP at L4/5 and the LVS scale, preoperative and postoperative low back pain, as well as the Oswestry Disability Index was assessed. The association of IVP at L4/5 and the LVS scale and surgical decision-making, defined as decompression alone or decompression and fusion, was assessed through univariable logistic regression analysis.

RESULTS

A total of 167 patients (52.7% female) were included in the study. The median age was 69 years (interquartile range 62-72). Overall, 100 (59.9%) patients underwent decompression and fusion and 67 (40.1%) underwent decompression alone. The univariable regression demonstrated a significantly increased odds ratio (OR) for back pain in patients with more severe IVP at L4/5 [OR=1.69 (95% CI 1.12-2.60), P =0.01]. The univariable regressions demonstrated a significantly increased OR for increased disability with more severe L4/L5 IVP [OR=1.90 (95% CI 1.04-3.76), P =0.04] and with an increased LVS scale [OR=1.17 (95% CI 1.02-1.35), P =0.02]. IVP severity of the L4/L5 were associated with higher indication for fusion surgery.

CONCLUSION

Our study showed that in patients with degenerative spondylolisthesis undergoing surgery, the severity of vacuum phenomenon at L4/L5 was associated with greater preoperative back pain and worse Oswestry Disability Index. Patients with severe IVP were more likely to undergo fusion.

Predicting postoperative outcomes in lumbar spinal fusion: development of a machine learning model

BACKGROUND CONTEXT

Degenerative lumbar spondylolisthesis (DLS) is a prevalent spinal disorder, often requiring surgical intervention. Accurately predicting surgical outcomes is crucial to guide clinical decision-making, but this is challenging due to the multifactorial nature of postoperative results. Traditional risk assessment tools have limitations, and with the advent of machine learning, there is potential to enhance the precision and comprehensiveness of preoperative evaluations.

PURPOSE

We aimed to develop a machine-learning algorithm to predict surgical outcomes in patients with degenerative lumbar spondylolisthesis (DLS) undergoing spinal fusion surgery, only using preoperative data.

STUDY DESIGN

Retrospective cross-sectional study.

PATIENT SAMPLE

Patients with DLS undergoing lumbar spinal fusion surgery.

OUTCOME MEASURES

This study aimed to predict the occurrence of lower back pain (LBP) ≥4 on the numeric analogue scale (NAS) 2 years after surgery. LBP was evaluated as the average pain patients experienced at rest in the week before questioning. NAS ranges from 0 to 10, 0 representing no pain and 10 representing the worst pain imaginable.

METHODS

We conducted a retrospective analysis of prospectively enrolled patients who underwent spinal fusion surgery for degenerative lumbar spondylolistheses at our institution in the United States between January 2016 and December 2018. The initial patient characteristics to be included in the training of the model were chosen by clinical expertise and through a literature review and included demographic characteristics, comorbidities, and radiologic features. The data was split into a training and validation datasets using a 60/40 split. Four different machine learning models were trained, including the modern XGBoost model, logistic regression, random-forest, and support vector machine (SVM). The models were evaluated according to the area under the curve (AUC) of the receiver operating characteristics (ROC) curve. An AUC of 0.7 to 0.8 was considered fair, 0.8 to 0.9 good, and ≥ 0.9 excellent. Additionally, a calibration plot and the Brier score were calculated for each model.

RESULTS

A total of 135 patients (66% female) were included. A total of 38 (28%) patients reported LBP ≥ 4 after 2 years, representing the positive class. The XGBoost model demonstrated the best performance in the validation set with an AUC of 0.81 (95% CI 0.67-0.95). The other machine learning models performed significantly worse: with an AUC of 0.52 (95% CI 0.37-0.68) for the SVM, 0.56 (95% CI 0.37-0.76) for the logistic regression and an AUC of 0.56 (95% CI 0.37-0.78) for the random forest. In the XGBoost model age, composition of the erector spinae, and severity of lumbar spinal stenosis as were identified as the most important features.

CONCLUSIONS

This study represents a novel approach to predicting surgical outcomes in spinal fusion patients. The XGBoost demonstrated a better performance compared with classical models and highlighted the potential contributions of age and paraspinal musculature atrophy as significant factors. These findings have important implications for enhancing patient care through the identification of high-risk individuals and modifiable risk factors. As the incorporation of machine learning algorithms into clinical decision-making continues to gain traction in research and clinical practice, our insights reinforce this trajectory by showcasing the potential of these techniques in forecasting surgical results.

Differences in imaging and clinical characteristics are associated with higher rates of decompression-fusion versus decompression-alone in women compared to men for lumbar degenerative spondylolisthesis

PURPOSE

The goals were to ascertain if differences in imaging/clinical characteristics between women and men were associated with differences in fusion for lumbar degenerative spondylolisthesis.

METHODS

Patients had preoperative standing radiographs, CT scans, and intraoperative fluoroscopic images. Symptoms and comorbidity were obtained from patients; procedure (fusion-surgery or decompression-alone) was obtained from intraoperative records. With fusion surgery as the dependent variable, men and women were compared in multivariable logistic regression models with clinical/imaging characteristics as independent variables. The sample was dichotomized, and analyses were repeated with separate models for men and women.

RESULTS

For 380 patients (mean age 67, 61% women), women had greater translation, listhesis angle, lordosis, and pelvic incidence, and less diastasis and disc height (all p ≤ 0.03). The rate of fusion was higher for women (78% vs. 65%; OR 1.9, p = 0.008). Clinical/imaging variables were associated with fusion in separate models for men and women. Among women, in the final multivariable model, less comorbidity (OR 0.5, p = 0.05), greater diastasis (OR 1.6, p = 0.03), and less anterior disc height (OR 0.8, p = 0.0007) were associated with fusion. Among men, in the final multivariable model, opioid use (OR 4.1, p = 0.02), greater translation (OR 1.4, p = 0.0003), and greater diastasis (OR 2.4, p = 0.0002) were associated with fusion.

CONCLUSIONS

There were differences in imaging characteristics between men and women, and women were more likely to undergo fusion. Differences in fusion within groups indicate that decisions for fusion were based on composite assessments of clinical and imaging characteristics that varied between men and women.