Effect of Clinical and Radiographic Degenerative Spondylolisthesis Classification on Patient-reported Outcomes and Spinopelvic Parameters for Patients With Single-level L4-L5 Degenerative Spondylolisthesis After Lumbar Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To determine whether preoperative clinical and radiographic degenerative spondylolisthesis (CARDS) classification is associated with differences in patient-reported outcomes and spinopelvic parameters after posterior decompression and fusion for L4-L5 degenerative spondylolisthesis (DS). SUMMARY: The CARDS classification for lumbar DS, an alternative to the Meyerding system, considers additional radiographic findings such as disc space collapse and segmental kyphosis and stratifies DS into 4 radiographically distinct classes. Although CARDS has been shown to be a reliable and reproducible method for classifying DS, very few studies have assessed whether the CARDS types represent distinct clinical entities. PATIENTS AND METHODS: A retrospective cohort analysis was conducted on patients with L4-L5 DS who underwent posterior lumbar decompression and fusion. Changes in spinopelvic alignment and patient-reported outcomes measures, including recovery ratios and percentage of patients achieving the minimal clinically important difference, were compared among patients in each CARDS classification 1-year postoperatively using analysis of variance or Kruskal-Wallis H with Dunn post hoc analysis. Multiple linear regression determined whether CARDS groups significantly predicted patient-reported outcomes measures, lumbar lordosis (LL), and pelvic incidence-lumbar lordosis mismatch (PI-LL) while controlling for demographic and surgical characteristics. RESULTS: Preoperative type B spondylolisthesis predicted decreased improvement in "physical component and mental component score of the short form-12" compared with type A spondylolisthesis (ß-coefficient = -5.96, P = 0.031) at 1 year. Significant differences were found between CARDS groups with regards to ΔLL (A: -1.63 degrees vs B: -1.17 degrees vs C: 2.88 degrees vs D: 3.19 degrees, P = 0.010) and ΔPI-LL (A: 1.02 degrees vs B: 2.09 degrees vs C: -2.59 degrees vs D: -3.70 degrees, P = 0.012). Preoperative type C spondylolisthesis was found to predict increased LL (ß-coefficient = 4.46, P = 0.0054) and decreased PI-LL (ß-coefficient = -3.49, P = 0.025) at 1 year compared with type A spondylolisthesis. CONCLUSIONS: Clinical and radiographic outcomes differed significantly by preoperative CARDS classification type for patients undergoing posterior decompression and fusion for L4-L5 DS. LEVEL OF EVIDENCE: Level III.

Does Facet Distraction Affect Patient Outcomes After ACDF?

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim of this study is to determine if there is a correlation between the amount of facet distraction and postoperative patient-reported outcomes after ACDF. METHODS: A retrospective cohort analysis of patients undergoing 1 to 3 level ACDF for degenerative pathologies at a single academic center was performed. Each patient received upright, lateral cervical spine x-rays at the immediate postoperative time point from which interfacet distance (facet distraction) was measured. Patient-reported outcome measures including NDI, PCS-12, MCS-12, VAS Neck, and VAS Arm pain scores were obtained preoperatively and at short-term (<3 months) and long-term (>1 year) follow-up. Receiver operating curves were generated to evaluate the possibility of a critical interfacet distraction distance. Univariate and multivariate analysis were performed to compare outcomes between groups based on the degree of facet distraction. RESULTS: A total of 229 patients met the inclusion criteria. Receiver operating curves failed to yield a critical interfacet distraction distance associated with worse post-operative outcomes. Patients were instead grouped based on facet distraction distance below and above the third quartile (0.8mm-2.0 mm, 2.0mm-3.7 mm), with 173 and 56 patients in each respective group. Univariate analysis did not detect any statistically significant differences in outcome measures, recovery ratio, or % MCID achievement at short- and long-term follow-up between groups. Multivariate analysis also failed to demonstrate any significant differences between the facet distraction groups. CONCLUSION: Increased interfacet distance did not correlate with increased neck pain or disability after an ACDF.

How Do Patients With Predominant Neck Pain Improve After Anterior Cervical Discectomy and Fusion for Cervical Radiculopathy?

BACKGROUND: The presence of predominant pain in the arm vs the neck as a predictor of postoperative outcomes after anterior cervical discectomy and fusion (ACDF) has been seldom reported; therefore, the purpose of this study was to determine whether patients with predominant neck pain improve after surgery compared to patients with predominant arm pain or those with mixed symptoms in patients undergoing ACDF for radiculopathy. METHODS: A retrospective cohort study was conducted on patients who underwent ACDF at a single center from 2016 to 2018. Patients were split into groups based on preoperative neck and arm pain scores: neck (N) pain dominant group (visual analog scale [VAS] neck ≥ VAS arm by 1.0 point); neutral group (VAS neck < VAS arm by 1.0 point); or arm (A) pain dominant group (VAS arm ≥ VAS neck by 1.0 point), using a threshold difference of 1.0 point. Subsequently, individuals were substratified into 2 groups based on the arm to neck pain ratio (ANR): non-arm pain dominant defined as ANR ≤1.0 and arm pain dominant (APD) defined as ANR >1.0. Patient-reported outcome measurements including Neck Disability Index (NDI), Physical Component Score-12, and Mental Component Score (MCS-12) were compared between groups. RESULTS: No significant differences between groups when stratifying patients using a threshold difference of 1.0 point. When stratifying patients using the ANR, those in the APD group had significantly higher postoperative MCS-12 (P = 0.008) and NDI (P = 0.011) scores. In addition, the APD group showed a greater magnitude of improvement for MCS-12 and NDI scores (P = 0.043 and P = 0.038, respectively). Multiple linear regression showed that the A and the APD groups were both independent predictors of improvement in NDI. CONCLUSION: Patients with dominant arm pain showed significantly greater improvement in terms of MCS-12 and NDI scores compared to patients with dominant neck pain. CLINICAL RELEVANCE: To compare the impact of ACDF on arm and neck pain in the context of cervical radiculopathy using patient-reported outcome measures as an objective measurement.

The Impact of Upper Cervical Spine Alignment on Patient-reported Outcome Measures in Anterior Cervical Decompression and Fusion.

STUDY DESIGN: This was a retrospective cohort study. OBJECTIVE: To determine the extent to which the upper cervical spine compensates for malalignment in the subaxial cervical spine, and how changes in upper cervical spine sagittal alignment affect patient-reported outcomes. SUMMARY OF BACKGROUND DATA: Previous research has investigated the relationship between clinical outcomes and radiographic parameters in the subaxial cervical spine following anterior cervical discectomy and fusion (ACDF). However, limited research exists regarding the upper cervical spine (occiput to C2), which accounts for up to 40% of neck movement and has been hypothesized to compensate for subaxial dysfunction. MATERIALS AND METHODS: Patients undergoing ACDF for cervical radiculopathy and/or myelopathy at a single center with minimum 1-year follow-up were included. Radiographic parameters including cervical sagittal vertical axis, C0 angle, C1 inclination angle, C2 slope, Occiput-C1 angle (Oc-C1 degrees), Oc-C2 degrees, Oc-C7 degrees, C1-C2 degrees, C1-C7 degrees, and C2-C7 degrees cervical lordosis (CL) were recorded preoperatively and postoperatively. Delta (Δ) values were calculated by subtracting preoperative values from postoperative values. Correlation analysis as well as multiple linear regression analysis was used to determine relationships between radiographic and clinical outcomes. Alpha was set at 0.05. RESULTS: A total of 264 patients were included (mean follow-up 20 mo). C2 slope significantly decreased for patients after surgery (Δ=-0.8, P =0.02), as did parameters of regional cervical lordosis (Oc-C7 degrees, C1-C7 degrees, and C2-C7 degrees; P <0.001, <0.001, and 0.01, respectively). Weak to moderate associations were observed between postoperative CL and C1 inclination ( r =-0.24, P <0.001), Oc-C1 degrees ( r =0.59, P <0.001), and C1-C2 degrees ( r =-0.23, P <0.001). Increased preoperative C1-C2 degrees and Oc-C2 degrees inversely correlated with preoperative SF-12 Mental Composite Score (MCS-12) scores ( r =-0.16, P =0.01 and r =-0.13, P =0.04). Cervical sagittal vertical axis was found to have weak but significant associations with Short Form-12 (SF-12) Physical Composite Score (PCS-12) ( r =-0.13, P =0.03) and MCS-12 ( r =0.12, P =0.05). CONCLUSION: No clinically significant relationship between upper cervical and subaxial cervical alignment was detected for patients undergoing ACDF for neurological symptoms. Upper cervical spine alignment was not found to be a significant predictor of patient-reported outcomes after ACDF. LEVEL OF EVIDENCE: Level III.

Stability in Direct Lateral vs Direct Anterior Total Hip Arthroplasty in the Context of Lumbar Spinal Fusion.

INTRODUCTION: Lumbar spinal fusion (LSF) may increase the risk of dislocation in patients who have undergone total hip arthroplasty (THA), especially when the LSF was done before the THA. Most publications evaluated patients who had undergone THA using a posterior approach to the hip, yet there are little data on the influence of other surgical approaches. The goal of this study was to evaluate the risk of THA dislocation with anterior supine-based surgical approaches to the hip in patients who have undergone surgical management of concurrent hip and spine pathology. METHODS: Patients older than 18 years who underwent an LSF and THA using a supine approach-either direct anterior (DA) or direct lateral (DL)-between 2000 and 2018 were identified. Only standard bearings (28-32-36-40 mm) were used. The dislocation rate was determined in this cohort. A subsequent analysis was conducted, stratifying patients based on the order in which they received the LSF or THA. RESULTS: A total of 582 surgical hip-spine patients were retrospectively identified and included in the cohort. Of total, 332 patients (57.0%) received an LSF before the THA; 250 (43.0%) had the fusion after a primary hip replacement. There were 143 patients (24.6%) in the DA group and 439 (75.4%) in the DL group. Overall, there were five dislocations (0.9%) in the entire cohort. CONCLUSIONS: In patients with simultaneous degenerative hip and lumbar spine pathology, anterior supine-based approaches demonstrate a low (<1%) risk of instability. Given the small number of total dislocation events (n = 5), additional analysis is warranted to assess the effect of different anterior approaches (DA versus DL) or timing of lumbar spinal surgery (before or after THA). LEVEL OF EVIDENCE: Level III.

Does the Size or Location of Lumbar Disc Herniation Predict the Need for Operative Treatment?

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The goal of this study was to determine whether the absolute size (mm2), relative size (% canal compromise), or location of a single-level, lumbar disc herniation (LDH) on axial and sagittal cuts of magnetic resonance imaging (MRI) were predictive of eventual surgical intervention. METHODS: MRIs of 89 patients were reviewed, and patients were split into groups based on type of management received (34 nonoperative vs 55 microdiscectomy). Radiographic characteristics-including size of disc herniation (mm2), size of spinal canal (mm2), location of herniation on axial (central, paracentral, foraminal) and sagittal (disc level, suprapedicle, pedicle, infrapedicle) planes, and type of herniation (bulge, protrusion, extrusion, sequestration)-were measured by 2 independent, orthopedic spine fellows and compared between groups via univariate and multivariate analyses. RESULTS: The operative group showed a significantly higher percentage of canal compromise (39.5% vs 31.1%, P = .001) compared to the nonoperative group. Multiple logistic regression analysis showed higher odds of eventual operative intervention for a disc protrusion (odds ratio [OR] 6.30 [1.99, 19.86], P = .002) or disc extrusion (OR 11.5 [1.63, 81.2], P = .014) for Rater 1 and a higher odds of eventual surgical management for a paracentral location for both Rater 1 and Rater 2 (OR = 3.39 [1.25, 9.22], P = .017, and OR = 5.46 [1.77, 16.8], P = .003, respectively). CONCLUSIONS: Disc herniations in a paracentral location were more likely to undergo operative treatment than those more centrally located, on axial MRI views.

Do Patients with Back Pain-Dominant Symptoms Improve After Lumbar Surgery for Radiculopathy or Claudication?

BACKGROUND: Currently, few studies have examined whether patients with back or leg pain-predominant symptoms fare better clinically after lumbar spine surgery; therefore, the purpose of this study was to determine whether patients with back pain-dominant symptoms improved to a similar degree as patients with mixed or leg pain-dominant symptoms after lumbar surgery. METHODS: A retrospective cohort study was conducted at a single academic center, in which patients were stratified into three groups: (1) back pain-dominant group (B) (visual analog score [VAS] back - VAS leg ≥ 1.0 point), (2) neutral group (N) (VAS back - VAS leg < 1.0 point), or (3) leg pain-dominant group (L) (VAS leg - VAS back ≥ 1.0 point), using a VAS threshold difference of 1.0 point. As a secondary analysis, the VAS leg-to-back pain (LBR) ratio was used to further stratify patients: (1) nonleg pain-dominant (NLPD) group (LBR ≤ 1.0) or (2) leg pain-dominant (LPD) group (LBR > 1.0). Patient outcomes, including physical component score of the short form-12 survey (PCS-12), mental component score of the short form-12 survey (MCS-12), and Oswestry Disability Index (ODI), were identified and compared between groups using univariate and multivariate analysis. RESULTS: There were no significant differences in preoperative, postoperative, or delta scores for PCS-12 or ODI scores between groups. In patients undergoing decompression surgery, those with back pain-dominant or mixed symptoms (B, N, or NLPD groups) did not improve with respect to MCS-12 scores after surgery (P > .05), and those with leg pain-dominant symptoms (LPD group) had greater delta MCS-12 scores (P = .046) and greater recovery rates (P = .035). Multiple linear regression did not find LPD to be an independent predictor of PCS-12 or ODI scores. CONCLUSION: Patients undergoing lumbar decompression surgery and leg pain-dominant symptoms noted a greater improvement in MCS-12 scores; however, there were no differences in PCS-12 or ODI scores. LEVEL OF EVIDENCE: 3. CLINICAL RELEVANCE: Patients undergoing lumbar decompression surgery demonstrate no major clinically significant differences when split up by pain-dominance groups.

Can Imaging Characteristics on Magnetic Resonance Imaging Predict the Acuity of a Lumbar Disc Herniation?

BACKGROUND: Currently, no authors of existing studies have attempted to classify the signal characteristics of disc herniation on magnetic resonance imaging (MRI) and their temporal relationship to symptoms of lumbar radiculopathy. The purpose of this study was to determine whether the MRI signal characteristics are predictive of acuity of symptoms in patients with lumbar disc herniation (LDH). METHODS: A retrospective cohort study was conducted on patients treated at an academic center for LDH from 2015 to 2018. Patients were divided into 2 groups based on symptom duration (acute: ≤6 weeks; or chronic: >4 months). Two independent observers measured T1, T2 signal, and other MRI characteristics at the affected disc level. Univariate analysis was used to compare differences between groups. Multiple logistic regression was used to determine predictors of acuity. RESULTS: Eighty-nine patients were included (33 acute, 56 chronic) with no significant baseline differences between groups. Rater 2 observed a higher proportion of disc bulges in the chronic group (P = .021) and a higher abnormal T1 herniation signal in the acute group (P = .048). Rater 1 found a higher Pfirrmann grade (P = .005) and a higher prevalence of vertebral body spurring (P = .007) in the chronic group. Interobserver agreement for T1 central and herniation signals demonstrated poor to fair agreement, whereas the remainder of the measurements showed moderate to substantial agreement (κ = 0.4-0.8). Multiple logistic regression showed that Pfirrmann Grade 5 (odds ratio = 0.12, 95% confidence interval [0.02, 0.74], P = .022) and anterior/posterior spurring (odds ratio = 0.053 [0.03, 0.85], P = .023) were not associated with acuity. CONCLUSIONS: Other than Pfirrmann grade or vertebral body spurring, no MRI characteristics could be reliably identified that correlate with acuity of symptoms. LEVEL OF EVIDENCE: 3.

How Does the Presence of a Surgical Trainee Impact Patient Outcomes in Lumbar Fusion Surgery?

BACKGROUND: While the impact of trainee involvement in other surgical fields is well established, there is a paucity of literature assessing this relationship in orthopaedic spine surgery. The goal of this study was to further elucidate this relationship. METHODS: A retrospective cohort study was initiated on patients undergoing 1-3 level lumbar spine fusion at a single academic center. Operative reports from cases were examined, and patients were divided into 2 groups depending on whether a fellow or resident (F/R) or a physician's assistant (PA) was used as the primary assist. Patients with less than 1-year follow-up were excluded. Multiple linear regression was used to assess change in each patient-reported outcome, and multiple binary logistic regression was used to determine significant predictors of revision, infection, and 30- or 90-day readmission. RESULTS: One hundred and seventy-two patients were included in the F/R group compared with 178 patients in the PA group. No differences existed between groups for total surgery time, length of stay, 30- or 90-day readmissions, infection, or revision rates. No differences existed between groups in terms of patient-reported outcomes preoperatively or postoperatively. In addition, presence of a surgical trainee was not a significant predictor of patient outcomes or rates of infection, overall revision, or 30- and 90-day readmission rates. CONCLUSIONS: The results of this study indicate the presence of an orthopaedic spine F/R does not increase complication rates and does not affect short-term patient-reported outcomes in lumbar decompression and fusion surgery. LEVEL OF EVIDENCE: 3.

Lumbar Pedicle Morphology and Vertebral Dimensions in Isthmic and Degenerative Spondylolisthesis-A Comparative Study.

BACKGROUND: The pedicle screw is the most common device used to achieve fixation in fusion of spondylolistheses. Safe and accurate placement with this technique relies on a thorough understanding of the bony anatomy. There is a paucity of literature comparing the surgically relevant osseous anatomy in patients with a degenerative spondylolisthesis (DS) and an isthmic spondylolisthesis (IS). The goal of this study was to determine the differences in the osseous anatomy in patients with a DS and those with an IS. METHODS: A retrospective comparative cohort study was conducted on patients with a single-level, symptomatic L4-L5 DS or a single-level, symptomatic L5-S1 IS. Magnetic resonance imaging for these patients was reviewed. Morphometries of the pedicle and vertebral body were analyzed by 2 independent observers for the levels from L3 to S1, and radiographic parameters were compared between groups. RESULTS: A total of 572 levels in 143 patients were studied, including 103 patients with a DS and 40 with an IS. After accounting for confounders, IS and DS had an independent effect on transverse vertebral body width, pedicle height and width, and sagittal pedicle angle. Patients with an IS had a smaller pedicle height (P < .001) and pedicle width (P = .001) than patients with DS. In addition, the angulation of the pedicles varied on the basis of the diagnosis. CONCLUSIONS: The osseous anatomy is significantly different in patients with a DS than with an IS. Patients with an IS have smaller pedicles in the lumbar spine. Also, the L4 and L5 pedicles are more caudally angulated and the S1 pedicle is less medialized. LEVEL OF EVIDENCE: 3. CLINICAL RELEVANCE: Understanding the differences in pedicle anatomy is important for the safe placement of pedicle screws.

Combined Depression and Anxiety Influence Patient-Reported Outcomes after Lumbar Fusion.

BACKGROUND: Currently, no studies have assessed what effect the presence of both anxiety and depression may have on patient-reported outcome measurements (PROMs) compared to patients with a single or no mental health diagnosis. METHODS: Patients undergoing 1- to 3-level lumbar fusion at a single academic hospital were retrospectively queried. Anyone with depression and/or anxiety was identified using an existing clinical diagnosis in the medical chart. Patients were separated into 3 groups: no depression or anxiety (NDA), depression or anxiety alone (DOA), and combined depression and anxiety (DAA). Absolute PROMs, recovery ratios, and the percentage of patients achieving minimal clinically important difference (% MCID) between groups were compared using univariate and multivariate analysis. RESULTS: Of the 391 patients included in the cohort, 323 (82.6%) were in the NDA group, 37 (9.5%) in the DOA group, and 31 (7.9%) in the DAA group. Patients in the DAA group had significantly worse outcome scores before and after surgery with respect to Short Form-12 mental component score (MCS-12) and Oswestry Disability Index (ODI) scores (P <.001); however, the change in PROMs, recovery ratio, % MCID were not found to be significantly different between groups. Using multivariate analysis, the DAA group was found to be an independent predictor of worse improvement in MCS-12 and ODI scores (P = .026 and P = .001, respectively). CONCLUSIONS: Patients with combined anxiety and depression fared worse with respect to disability before and after surgery compared to patients with a single diagnosis or no mental health diagnosis; however, there were no significant differences in recovery ratio or % MCID. LEVEL OF EVIDENCE: 3. CLINICAL RELEVANCE: Combined anxiety and depression may predict less improvement in MCS-12 and ODI after lumbar arthrodesis compared with single or no mental health diagnosis.

Patient Outcomes Following Short-segment Lumbar Fusion Are Not Affected by PI-LL Mismatch.

STUDY DESIGN: This is a retrospective cohort study. OBJECTIVE: The objective of this study was to further elucidate the relationship between pelvic incidence-lumbar lordosis (PI-LL) mismatch and surgical outcomes in patients undergoing short segment lumbar fusions for degenerative lumbar disease. SUMMARY OF BACKGROUND DATA: There are few studies examining the relationship between spinopelvic parameters and patient reported outcome measurements (PROMs) in short segment lumbar degenerative disease. MATERIALS AND METHODS: A retrospective review was conducted at single academic institution. Patients undergoing 1- or 2-level lumbar fusion were retrospectively identified and separated into 2 groups based on postoperative PI-LL mismatch ≤10 degrees (NM) or PI-LL mismatch >10 degrees (M). Outcomes including the Physical Component Score (PCS)-12, Mental Component Score (MCS)-12, Oswestry Disability Index (ODI), Visual Analog Scale (VAS) back and leg scores were analyzed. Absolute PROM scores, the recovery ratio and the percentage of patients achieving minimum clinically important difference between groups were compared and a multiple linear regression analysis was performed. RESULTS: A total of 306 patients were included, with 59 patients in the NM group and 247 patients in the M group. Patients in the M group started with a higher degree of PI-LL mismatch compared with the NM group (22.2 vs. 7.6 degrees, P<0.001) and this difference increased postoperatively (24.7 vs. 2.5 degrees, P<0.001). There were no differences between the 2 groups in terms of baseline, postoperative, or Δ outcome scores (P>0.05). In addition, having a PI-LL mismatch was not found to be an independent predictor of any PROM on multivariate analysis (P>0.05). CONCLUSION: The findings in this study show that even though patients in the M group had a higher degree of mismatch preoperatively and postoperatively, there was no difference in PROMs. LEVEL OF EVIDENCE: Level III.

Transpsoas Lumbar Interbody Fusion Without Psoas Stimulated Electromyography.

STUDY DESIGN: This is a retrospective case review. OBJECTIVE: The objective of this study was to present an anatomic approach to transpsoas interbody fusion without psoas stimulated electromyography (sEMG) and to evaluate the rate of neurological and approach-related complications. BACKGROUND: The transpsoas approaches have become commonly utilized for lumbar interbody fusion and may have certain advantages compared with other methods of interbody stabilization. Traditionally, transpsoas approaches have been performed utilizing sEMG as it has been purported to reduce the risk of injury to the lumbar plexus; however, an anatomic approach to transpsoas surgery is also possible as cadaveric studies have demonstrated the anatomy of the psoas muscle and lumbar plexus. METHODS: Patients who underwent transpsoas interbody fusion using an anatomic approach without psoas sEMG between 2005 and 2018 were enrolled in this study. The preoperative and postoperative medical records for this cohort were carefully reviewed to identify any new or persistent radicular symptoms, neurological deficits or approach-related complications. RESULTS: A total of 133 patients (48 males, 85 females) underwent transpsoas interbody fusion at 222 levels in this cohort-which had a mean age of 63 (61, 65) years and body mass index of 28.8 (27.8, 29.9). New neurological complications were seen in 5 patients (3.8%) and 5 patients (3.8%) were found to have new postoperative radicular pain, up to 3 months postoperatively. The total number of perioperative, approach-related complications was 7 (5.3%) for the entire cohort. CONCLUSION: An anatomic transpsoas approach to the interbody space without psoas sEMG demonstrated a rate of neurological and approach-related complications that was comparable or superior to the rate of complications reported using the traditional transpsoas approach with sEMG.

How Does Smoking Influence Patient-reported Outcomes in Patients After Lumbar Fusion?

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: The goal of this study was to determine the effect of smoking on patient-reported outcome measurements (PROMs) after lumbar fusion surgery. SUMMARY OF BACKGROUND DATA: Although smoking is known to decrease fusion rates after lumbar fusion, there is less evidence regarding the influence of smoking on PROMs after surgery. METHODS: Patients undergoing between 1 and 3 levels of lumbar fusion were divided into 3 groups on the basis of preoperative smoking status: never smokers (NS); current smokers (CS); and former smokers (FS). PROMs collected for analysis include the Physical Component Score (PCS-12), Mental Component Score (MCS-12), Oswestry Disability Index (ODI), and Visual Analogue Scale back (VAS back) and leg (VAS leg) pain scores. Preoperative and postoperative PROMs were compared between groups. A multiple linear regression analysis was performed to determine whether preoperative smoking status was a predictor of change in PROM scores. RESULTS: A total of 220 (60.1%) NS, 52 (14.2%) CS, and 94 (25.7%) FS patients were included. Patients in most groups improved within each of the PROMs analyzed (P<0.05). VAS leg pain (P=0.001) was found to significantly differ between groups, with NS and FS having less disability than CS (3.6 vs. 2.0, P=0.010; and 3.6 vs. 2.4, P=0.022; respectively). Being a CS significantly predicted less improvement in ODI (P=0.035), VAS back (P=0.034), and VAS leg (P<0.001) compared with NS. In addition, NS had a significantly lower 30-day readmission rate than CS or FS (3.2% vs. 5.8% and 10.6%, respectively, P=0.029). CONCLUSION: CS exhibited worse postoperative VAS leg pain and a lower recovery ratio than never smokers. In addition, being in the CS group was a significant predictor of decreased improvement in ODI, VAS back, and VAS leg scores. LEVEL OF EVIDENCE: Level III.

Processing and Handling Cost of Single-use Versus Traditional Instrumentation for 1 Level Lumbar Fusions.

STUDY DESIGN: A single center, observational prospective clinical study. OBJECTIVE: The aim of this study was to compare the instrumentation-related cost and efficiency of single-use instrumentation versus traditional reusable instrument trays. SUMMARY OF BACKGROUND DATA: Single-use instrumentation provides the opportunity to reduce costs associated with cleaning and sterilizing instrumentation after surgery. Although previous studies have shown single-use instrumentation is effective in other orthopedic specialties, it is unclear if single-use instrumentation could provide economic advantages in spine surgery. MATERIALS AND METHODS: A total of 40 (20 reusable instrumentation and 20 single-use instrumentation) lumbar decompression (1-3 level) and fusion (1 level) spine surgeries were collected. Instrument handling, opening, setup, re-stocking, cleaning, sterilization, inspection, packaging, and storage were recorded by direct observation for both reusable and single-use instrumentation. The rate of infection was noted for each group. RESULTS: Mean time of handling instruments by the scrub nurse was 11.6 (±3.9) minutes for reusable instrumentation and 2.1 (±0.5) minutes for single-use instrumentation. Mean cost of handling reusable instruments was estimated to be $8.52 (±$2.96) per case, and the average cost to reprocess a single tray by Sterilization Processing Department (SPD) was $58. Thus, the median cost for sterilizing 2 reusable trays per case was $116, resulting in an average total Costresuable of $124.52 (±$2.96). Mean cost of handling single-use instrumentation was estimated to be $1.57 ($0.38) per case. CONCLUSION: Single-use instrumentation provided greater cost savings and reduced time from the opening of instrumentation to use in surgery when compared with reusable instrumentation.

Are Patient Outcomes Affected by the Presence of a Fellow or Resident in Lumbar Decompression Surgery?

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim of this study was to determine whether the presence of a fellow or resident (F/R) compared to a physician assistant (PA) affected surgical variables or short-term patient outcomes. SUMMARY OF BACKGROUND DATA: Although orthopedic spine fellows and residents must participate in minimum number of decompression surgeries to gain competency, the impact of trainee presence on patient outcomes has not been assessed. METHODS: One hundred and seventy-one patients that underwent a one- to three-level lumbar spine decompression procedure at a high-volume academic center were retrospectively identified. Operative reports from all cases were examined and patients were placed into one of two groups based on whether the first assist was a F/R or a PA. Univariate analysis was used to compare differences in total surgery duration, 30-day and 90-day readmissions, infection and revision rates, patient-reported outcome measures (Short Form-12 Physical Component Score and Mental Component Score, Oswestry Disability Index, Visual Analog Scale [VAS] Back, VAS Leg) between groups. Multiple linear regression was used to assess change in each patient reported outcome and multiple binary logistic regression was used to determine significant predictors of revision, infection, and 30- or 90-day readmission. RESULTS: Seventy-eight patients were included in the F/R group compared to 93 patients in the PA group. There were no differences between groups for total surgery time, 30-day or 90-day readmissions, infection, or revision rates. Using univariate analysis, there were no differences between the two groups pre- or postoperatively (P > 0.05). Using multivariate analysis, presence of a surgical trainee did not significantly influence any patient reported outcome and did not affect infection, revision, or 30- and 90-day readmission rates. CONCLUSION: This is one of the first studies to show that the presence of an orthopedic spine fellow or resident does not affect patient short-term outcomes in lumbar decompression surgery. LEVEL OF EVIDENCE: 3.

Does Smoking Status Influence Health-Related Quality of Life Outcome Measures in Patients Undergoing ACDF?

STUDY DESIGN: Retrospective comparative study. OBJECTIVE: Whereas smoking has been shown to affect the fusion rates for patients undergoing an anterior cervical discectomy and fusion (ACDF), the relationship between smoking and health-related quality of life outcome measurements after an ACDF is less clear. The purpose of this study was to evaluate whether smoking negatively affects patient outcomes after an ACDF for cervical degenerative pathology. METHODS: Patients with tumor, trauma, infection, and previous cervical spine surgery and those with less than a year of follow-up were excluded. Smoking status was assessed by self-reported smoking history. Patient outcomes, including Neck Disability Index, Short Form 12 Mental Component Score, Short Form 12 Physical Component Score (PCS-12), Visual Analogue Scale (VAS) arm pain, VAS neck pain, and pseudarthrosis rates were evaluated. Outcomes were compared between smoking groups using multiple linear and logistic regression, controlling for age, sex, and body mass index (BMI), among other factors. A P value <.05 was considered significant. RESULTS: A total of 264 patients were included, with a mean follow-up of 19.8 months, age of 53.1 years, and BMI of 29.6 kg/m2. There were 43 current, 69 former, and 152 nonsmokers in the cohort. At baseline, nonsmokers had higher PCS-12 scores than current smokers (P = .010), lower VAS neck pain than current (P = .035) and former (P = .014) smokers, as well as lower VAS arm pain than former smokers (P = .006). Postoperatively, nonsmokers had higher PCS-12 scores than both current (P = .030) and former smokers (P = .035). Smoking status was not a significant predictor of change in patient outcome in multivariate analysis. CONCLUSIONS: Whereas nonsmokers had higher function and lower pain than former or current smokers preoperatively, smoking status overall was not found to be an independent predictor of outcome scores after ACDF. This supports the notion that smoking status alone should not deter patients from undergoing ACDF for cervical degenerative pathology.

Does Smoking Affect Short-Term Patient-Reported Outcomes After Lumbar Decompression?

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The goal of this study was to determine how smoking status influences patient-reported outcome measurements (PROMs) in patients undergoing lumbar decompression surgery. METHODS: Patients undergoing lumbar decompression between 1 to 3 levels at a single-center, academic hospital were retrospectively identified. Patients <18 years old, and those undergoing surgery for infection, trauma, tumor, or revision, with less than 12 months of follow-up were excluded. Patients were divided into 3 groups: (1) never smokers (NSs); (2) current smokers (CSs); and (3) former smokers (FSs). PROMs analyzed included the Physical Component Score and Mental Component Score of the Short Form-12 Health Survey, the Oswestry Disability Index, and Visual Analogue Scale Back and Leg pain scores. One-way ANOVA was used to compare preoperative and postoperative scores between smoking groups, and multiple linear regression analysis was performed to determine whether smoking status predicted change in each outcome score, controlling for factors such as age, sex, body mass index, and other clinical variables. A P value <.05 was considered to be significant. RESULTS: A total of 195 patients were included in the final cohort, with 121 (62.1%) patients in the NS group, 22 (11.3%) in the CS group, and 52 (26.6%) in the FS group. There were no significant differences between groups at baseline or postoperatively. Smoking status was also not a significant predictor of change in any outcome scores over time on multivariate analysis. CONCLUSION: These results suggest that smoking status does not significantly affect short-term complications or outcomes in patients undergoing lumbar decompression surgery.