Preoperative motor weakness and the impact on patient reported outcomes in lateral lumbar interbody fusion.

This study measures the impact of preoperative motor weakness (MW) on Patient-Reported Outcome Measures (PROMs) in lateral lumbar interbody fusion (LLIF) patients. Retrospectively-sourced data from a prospectively-maintained, single-surgeon database created two cohorts of LLIF patients: patients with/without documented MW. Demographics/perioperative characteristics/PROMs were collected preoperatively and at six-weeks/final follow-up (FF). Studied outcomes were Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF), 12-Item Short Form (SF-12) Physical/Mental Component Score (PCS/MCS), Patient Health Questionnaire (PHQ-9), Visual Analog Scale Back/Leg Pain (VAS-BP/LP), and Oswestry Disability Index (ODI). Multivariable linear/logistic regression calculated/compared intercohort minimum clinically important difference (MCID). Mean postoperative follow-up time was 11.5 ± 7.52 months. In total, 214 LLIF patients from December 2010 to May 2023 were included, with 149 having documented MW. In Table 1, self-reported gender was significant between cohorts (p < 0.025). Other significant demographic characteristics were smoker status (p < 0.002), diabetes (p < 0.016), and CCI score (p < 0.011). Table 2 shows notably significant perioperative characteristics: spinal pathology (degenerative spondylolisthesis/foraminal stenosis/herniated nucleus pulposus) (p < 0.005, all), estimated blood loss/length of stay/postoperative day (POD)-zero narcotic consumption (p < 0.001, all). Table 3 outcomes/MCID achievement percentages demonstrated insignificant intercohort differences besides a weakly significant FF ODI score (p < 0.036). MW, a frequently reported symptom in spine surgery, is poorly studied in LLIF patients. Thus, this study evaluates MW impact on PROMs and notes no significant differences. However, one exception regarding FF disability scores was recorded. MW did not affect MCID achievement for our patient population. Therefore, the preliminary findings suggest preoperative MW imparts minimal influence on PROMs/MCID in LLIF patients.

Prognostic value in preoperative Veterans RAND-12 mental Component score on clinical outcomes for patients undergoing minimally invasive transforaminal lumbar interbody fusion.

No study has examined the prognostic value of the Veterans RAND-12 (VR-12) Mental Component Score (MCS) on postoperative outcomes in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) patients. This study examines the effect of preoperative VR-12 MCS on postoperative patient-reported outcome measures (PROMs) in MIS-TLIF patients. Patients were separated into 2 cohorts: VR-12 MCS < 50 and VR-12 MCS ≥ 50. PROMs of VR-12 MCS/Physical Component Score (PCS), Short Form-12 (SF-12) MCS/PCS, Patient-Reported Outcomes Measurement Information System-Physical Function (PROMIS-PF), Patient Health Questionnaire-9 (PHQ-9), Visual Analog Scale (VAS) Back/Leg Pain (VAS-BP/LP), and Oswestry Disability Index (ODI) were collected.Of 329 patients, 151 were in the VR-12 MCS < 50 cohort. The VR-12 MCS < 50 cohort reported significantly inferior scores in all PROMs preoperatively, significantly inferior VR-12 MCS, SF-12 MCS, PROMIS-PF, PHQ-9, and ODI scores at 6-weeks postoperatively, and significantly inferior scores in all PROMs, except for VAS-BP at final follow-up. Magnitude of 6-week postoperative improvement was significantly greater in the VR-12 MCS < 50 cohort for VR-12 MCS, SF-12 MCS, and PHQ-9. Magnitude of final postoperative improvement was significantly greater in the VR-12 MCS < 50 cohort for VR-12 MCS, SF-12 MCS/PCS, and PHQ-9. MCID achievement rates were significantly greater in the VR-12 MCS < 50 cohort for VR-12 MCS, SF-12 MCS, and PHQ-9. MIS-TLIF patients with lesser preoperative VR-12 MCS reported inferior postoperative outcomes in mental health, physical function, pain, and disability. However, patients with inferior preoperative mental health reported greater rates of clinically meaningful improvement in mental health. Inferior preoperative mental health does not limit postoperative improvement in patients undergoing MIS-TLIF.

Cervical Disk Replacement Versus Anterior Cervical Diskectomy and Fusion: Effect of Procedural Variant on Patients With a Prolonged Preoperative Duration of Symptoms From Disk Herniation.

INTRODUCTION: Patients with a prolonged preoperative symptom duration (PSD) in the setting of cervical disk herniation (DH) may suffer inferior outcomes after surgical intervention. Comparison between anterior cervical diskectomy and fusion (ACDF) versus cervical disk arthroplasty (CDA) in this at-risk population has not yet been conducted. METHODS: Patients undergoing ACDF or CDA for DH with a PSD > 180 days were selected. Six-week (6W) and final follow-up (FF) patient-reported outcome measures (PROMs) as well as magnitude of postoperative improvements (∆PROM) were compared between cohorts using multivariable linear regression. Intercohort achievement rates of minimal clinically important difference (MCID) in each PROM were compared. RESULTS: Seventy-seven of 190 patients were in the CDA cohort. 6W Patient-Reported Outcomes Measurement Information System-Physical Function (PROMIS-PF) was superior in the CDA cohort. The ACDF cohort demonstrated notable improvements in the 6W Neck Disability Index (NDI), visual analog scale-neck pain (VAS-N), visual analog scale-arm pain (VAS-A), and 9-item Patient Health Questionnaire (PHQ-9). The CDA cohort demonstrated notable improvements in 6W PROMIS-PF, NDI, VAS-N, and VAS-A. FF VAS-A was better in the CDA cohort. The ACDF cohort demonstrated notable improvements in FF PROMIS-PF, NDI, VAS-N, and VAS-A. The CDA cohort demonstrated notable improvements in all FF PROMs. ∆PROM-6W in PROMIS-PF was greater in the CDA cohort. CONCLUSION: Patients with prolonged PSD due to cervical DH demonstrated notable improvements in physical function, disability, pain, and mental health regardless of fusion versus arthroplasty techniques. Accounting for demographic variations, patients undergoing CDA demonstrated a greater magnitude of improvement and superior scores in physical function at the first postoperative follow-up. Rates of clinically tangible improvements in PROMs did not markedly vary by surgical procedure. Patients undergoing CDA may perceive greater early improvements to physical function compared with patients undergoing ACDF for prolonged PSD due to DH.

Delayed Infection After Cervical Disc Arthroplasty: A Case Report and Review of the Literature.

STUDY DESIGN: Case report and literature review. OBJECTIVE: To report the relatively rare complication of delayed infection after cervical disc arthroplasty (CDA). BACKGROUND: Delayed infection of the M6 device has been a rarely reported complication, with all cases described outside of the United States. The reliability of positive intraoperative cultures remains an ongoing debate. METHODS: Cases were reviewed, and findings were summarized. A literature review was performed and discussed, with special consideration to current reports of delayed M6 infection, etiology, and utility of intraoperative cultures. RESULTS: We present a case of delayed infection 6 years after primary 1-level CDA with the M6 device. At revision surgery, gross purulence was encountered. Intraoperative cultures finalized with Staphylococcus epidermidis and Cutibacterium acnes. The patient was revised with removal of the M6 and conversion to anterior cervical discectomy and fusion. A prolonged course of intravenous antibiotics was followed by an oral course for suppression. At the final follow-up, the patient's preoperative symptoms had resolved. CONCLUSION: Delayed infection after CDA is a rare complication, with ongoing debate regarding the reliability of positive cultures. We describe an infected M6 and demonstrate the utility of implant removal, conversion to anterior cervical discectomy and fusion, and long-term antibiotics as definitive treatment. LEVEL OF EVIDENCE: Level V-case report and literature review.

The influence of preoperative Veterans RAND-12 physical composite score in patients undergoing anterior lumbar interbody fusion [Retrospective Review].

No study has evaluated the preoperative impact of Veterans RAND-12 Physical Composite Score (VR-12 PCS) on anterior lumbar interbody fusion (ALIF) patients. This study examines its influence on physical function, mental health, pain, and disability outcomes. Two cohorts of ALIF patients with preoperative VR-12 PCS scores were formed using a single-surgeon registry: VR-12 PCS < 30 and VR-12 PCS ≥ 30. Demographics, perioperative characteristics, and patient-reported outcome measures (PROMs) were collected. PROMs of VR-12 PCS/Mental Composite Score (MCS), Short Form-12 (SF-12) PCS/MCS, Patient-Reported Outcomes Measurement Information System-Physical Function (PROMIS-PF), Patient Health Questionnaire-9 (PHQ-9), Visual Analog Scale-Back/Leg Pain (VAS-BP/LP), and Oswestry Disability Index (ODI) were collected pre/postoperatively up to 2-years. Demographics, perioperative characteristics, and preoperative PROMs were compared. Intercohort postoperative 6-week/final PROMs and improvements were compared. Of 80 patients, there were 41 in the VR-12 PCS < 30 cohort. Besides VR-12 PCS, VR-12 PCS < 30 patients reported inferior preoperative VR-12 MCS/SF-12 PCS/PROMIS-PF/PHQ-9/ODI scores (p ≤ 0.003, all). At 6-weeks postoperatively, VR-12 PCS < 30 reported inferior VR-12 PCS/SF-12 PCS/PROMIS-PF/PHQ-9 (p ≤ 0.030, all). There was greater improvement up to 6-weeks postoperatively in VR-12 PCS < 30 for VR-12 PCS/MCS and SF-12 PCS (p ≤ 0.020, all). VR-12 PCS < 30 reported superior improvement by final follow-up in VR-12 PCS/SF-12 PCS/PHQ-9 (p ≤ 0.006, all). MCID achievement rates were higher in VR-12 PCS < 30 for PHQ-9 and ODI (p ≤ 0.013, both). VR-12 PCS < 30 patients reported inferior postoperative physical function, mental health, and disability, yet superior magnitude of improvement in physical function and mental health. Rates of clinically meaningful improvement for VR-12 PCS < 30 were greater in mental health and disability.

Preoperative diagnosis of mental health disorder and dysphagia following anterior cervical spine surgery.

OBJECTIVE: Mental health disorders (MHDs) have been linked to worse postoperative outcomes after various surgical procedures. Past studies have also demonstrated a higher prevalence of dysphagia in both acute and community mental health settings. Dysphagia is among the most common complications following anterior cervical spine surgery (ACSS); however, current literature describing the association between an established diagnosis of an MHD and the rate of dysphagia after ACSS is sparse. METHODS: All patients who underwent ACSS between 2014 and 2020 with a minimum of 6 months of follow-up were retrospectively evaluated at a single institution. Patients were divided into cohorts depending on an established diagnosis of an MHD: the first had no established MHD (non-MHD); the second included patients with a diagnosed MHD. Outcomes were measured using pre- and postoperative patient-reported outcome scores, which included the Swallowing Quality of Life survey for dysphagia, as well as physical and mental health questionnaires. Postoperative dysphagia surveys were obtained at final follow-up for both patient cohorts. RESULTS: A total of 68 and 124 patients with and without a diagnosis of a MHD were assessed. The MHD group reported significantly worse baseline Patient-Reported Outcomes Measurement Information System depression scale scores (p < 0.001), 12-Item Short-Form Health Survey (p < 0.001), and Veterans RAND 12-Item Health Survey (p = 0.001) mental health components compared to non-MHD group. This group continued to have worse mental health status in the postoperative period, as reported by Patient-Reported Outcomes Measurement Information System depression scale scores (p = 0.024), 12-Item Short-Form Health Survey (p = 0.019), and Veterans RAND 12-Item Health Survey (p = 0.027). Postoperative assessment of Swallowing Quality of Life scores (expressed as the mean ± SD) also showed worse dysphagia outcomes in the MHD cohort (80.1 ± 12.2) than in the non-MHD cohort (86.0 ± 12.1, p = 0.001). CONCLUSIONS: ACSS is associated with significantly higher postoperative dysphagia in patients diagnosed with an MHD when compared to patients without an established mental health diagnosis. Given the high prevalence of MHDs in patients with spinal pathology, it is important for spine surgeons to take note of the increased incidence of dysphagia faced by this patient population.

Do Six-Week Postoperative Patient-Reported Outcomes Predict Long-Term Clinical Outcomes Following Lumbar Decompression?

BACKGROUND: Little research has been done to evaluate the prognostic value of short-term postoperative patient-reported outcomes (PROs) on long-term PROs following lumbar decompression (LD). We evaluated the prognostic value of short-term PROs on long-term PROs through 2 years after LD. METHODS: A single spine surgeon database was retrospectively queried for patients undergoing primary LD with 6-week postoperative PROs reported. The demographics, perioperative traits, and preoperative, 6-month, 1-year, and 2-year PROs were recorded. The PROs included the visual analog scale (VAS) for back pain, VAS for leg pain, PRO measure information system for physical function (PROMIS-PF), and Oswestry disability index. Two-step multivariate linear regression was performed to determine the predictive value of 6-week PROs for the 6-month, 1-year, and 2-year PROs. RESULTS: A total of 277 patients were included. The 6-week Oswestry disability index, VAS for leg pain, and 9-item patient health questionnaire (PHQ-9) are all positive predictors for their respective outcomes at 6 months. Additionally, the 6-week PROMIS-PF was a negative predictor of the 6-month PHQ-9. The 6-week PROMIS-PF positively predicted the PROMIS-PF through 1 year, and the PHQ-9 was a positive predictor of the PHQ-9 at 1 and 2 years postoperatively. CONCLUSIONS: The 6-week postoperative PROs are predictive of the same outcomes at 6 months, the PROMIS-PF is predictive through 1 year, and the PHQ-9 is predictive through 2 years. Determining the predictive value of early postoperative PROs can be helpful in understanding the likely postoperative trajectory following LD and informing patient expectations.

Severe Preoperative Disability Is Associated With Greater Mental Health Improvements Following Surgery for Degenerative Spondylolisthesis: A Cohort Matched Analysis.

OBJECTIVE: To evaluate preoperative disability's influence on patient-reported outcomes (PROs) following surgery for degenerative spondylolisthesis (DS). METHODS: DS patients who underwent surgical intervention were retrospectively identified from a single-surgeon spine registry. Cohorts based on Oswestry Disability Index (ODI) < 41 (milder disability) and ≥ 41 (severe disability) were created. Demographic differences were accounted for with 1:1 propensity score matching. For the matched sample, perioperative and PRO data were additionally collected. PROs assessed included mental health, physical function, pain, and disability. Pre- and up to 2-year postoperative PROs were utilized. Average time to final follow-up was 15.7 ± 8.8 months. Improvements in PROs and minimal clinically important difference (MCID) rates were calculated. Continuous variables were compared through Student t-test and categorical variables were compared through chi-square tests. RESULTS: Altogether, 214 patients were included with 77 in the milder disability group. The severe disability group had worse postoperative day (POD) 1 pain scores and longer hospital stays (p ≤ 0.038, both). The severe disability group reported worse outcomes pre- and postoperatively (p < 0.011, all), but had greater average improvement in 12-item Short Form health survey mental composite score (SF-12 MCS), 9-Item Patient Health Questionnaire (PHQ-9), visual analogue scale (VAS)-back, and ODI by 6 weeks (p ≤ 0.037, all) and PHQ-9, VAS-back and ODI by final follow-up (p ≤ 0.015, all). The severe disability cohort was more likely to achieve MCID for SF-12 MCS, PHQ-9, and ODI (p ≤ 0.003, all). CONCLUSION: Patients with greater baseline disability report higher POD 1 pain and discharge later than patients with milder disability. While these patients report inferior physical/mental health before and after surgery, they report greater improvements in mental health and disability postoperatively.

Risk of Subsequent Fusion After Isolated Decompression of Lumbar Facet Cysts.

INTRODUCTION: Lumbar facet cysts represent a potential source of nerve root compression in elderly patients. Isolated decompression without fusion has proven to be a reasonable treatment option in properly indicated patients. However, the risk of lumbar fusion after isolated decompression and facet cyst excision has yet to be elucidated. METHODS: The PearlDiver database was reviewed for patients undergoing isolated laminectomy for lumbar facet cyst from January 2015 to December 2018 using Current Procedural Terminology coding. Patients undergoing concomitant fusion or additional decompression, as well as those diagnosed with preexisting spondylolisthesis or without a minimum of 5-year follow-up, were excluded. Rates of subsequent lumbar fusion and potential risk factors for subsequent fusion were identified. Statistical analysis included descriptive statistics, chi square test, and multivariate logistic regression. Results were considered significant at P < 0.05. RESULTS: In total, 10,707 patients were ultimately included for analysis. At 5-year follow-up, 727 (6.79%) of patients underwent subsequent lumbar fusion after initial isolated decompression. Of these, 301 (2.81% of total patients, 41.4% of fusion patients) underwent fusion within the first year after decompression. Multivariate analysis identified chronic kidney disease, hypertension, and osteoarthritis as risk factors for requiring subsequent lumbar fusion at 5 years following the index decompression procedure ( P < 0.033; all). CONCLUSION: Patients undergoing isolated decompression for lumbar facet cysts undergo subsequent lumbar fusion at a 5-year rate of 6.79%. Risk factors for subsequent decompression include chronic kidney disease, hypertension, and osteoarthritis. This study will assist spine surgeons in appropriately counseling patients on expected postoperative course and potential risks of isolated decompression.

Effect of Baseline Veterans RAND-12 Mental Composite Score on Postoperative Patient-Reported Outcome Measures for Cervical Disk Replacement.

STUDY DESIGN: Retrospective review. OBJECTIVE: To examine the effect of baseline Veterans RAND-12 (VR-12) Mental Composite Score (MCS) on clinical outcomes in patients undergoing cervical disk replacement (CDR) for herniated disk. BACKGROUND: Few studies in spine surgery have evaluated the impact of preoperative VR-12 MCS on postoperative outcomes in patients undergoing CDR. METHODS: Patients undergoing CDR for herniated disk were separated into 2 cohorts based on the VR-12 MCS standardized mean: VR-12 MCS<50 (worse mental health) and VR-12 MCS≥50 (better mental health). Patient-reported outcome measures of VR-12 MCS, VR-12 Physical Composite Score, Short Form-12 (SF-12) MCS, SF-12 Physical Composite Score, Patient-Reported Outcomes Measurement Information System Physical Function, Patient Health Questionnaire-9 (PHQ-9), Visual Analog Scale (VAS) Neck Pain, VAS Arm Pain, and Neck Disability Index were collected at preoperative and up to 2-year postoperative time points. RESULTS: In all, 109 patients were identified, with 50 patients in the worse mental health cohort. The worse mental health cohort reported inferior patient-reported outcome measures in all domains at preoperative, 6-week postoperative, and final postoperative time points. For 6-week postoperative improvement, the worse mental health cohort reported greater improvement for VR-12 MCS, SF-12 MCS, and PHQ-9. For final postoperative improvement, the worse mental health cohort reported greater improvement in VR-12 MCS and SF-12 MCS. Minimum clinically important difference achievement rates were higher in the worse mental health cohort for VR-12 MCS, SF-12 MCS, and PHQ-9. CONCLUSION: Patients undergoing cervical disk replacement for herniated disk with worse baseline mental health reported inferior clinical outcomes in mental health, physical function, pain, and disability outcomes throughout the postoperative period. Patients with worse baseline mental health demonstrated greater clinically meaningful improvement in mental health. In cervical disk replacement patients, those with worse baseline mental health may report inferior postoperative clinical outcomes but experience greater rates of tangible improvement in mental health.

Prognostic Value in Preoperative Veterans RAND-12 Mental Component Score on Clinical Outcomes for Patients Undergoing Minimally Invasive Lateral Lumbar Interbody Fusion.

OBJECTIVE: To evaluate the effect of Veterans RAND 12-item health survey mental composite score (VR-12 MCS) on postoperative patient-reported outcome measures (PROMs) after undergoing lateral lumbar interbody fusion. METHODS: Retrospective data from a single-surgeon database created 2 cohorts: patients with VR-12 MCS ≥ 50 or VR-12 MCS < 50. Preoperative, 6-week, and final follow-up (FF)- PROMs including VR-12 MCS/physical composite score (PCS), 12-item Short Form health survey (SF-12) MCS/PCS, Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF), Patient Health Questionnaire-9 (PHQ-9), visual analogue scale (VAS)-back/leg pain (VAS-BP/LP), and Oswestry Disability Index (ODI) were collected. ∆6-week and ∆FF-PROMs were calculated. Minimal clinically important difference (MCID) achievement rates were determined from established cutoffs from the literature. For intercohort comparison, chi-square analysis was used for categorical variables, and Student t-test for continuous variables. RESULTS: Seventy-nine patients were included; 25 were in VR-12 MCS < 50. Mean postoperative follow-up time was 17.12 ± 8.43 months. The VR-12 MCS < 50 cohort had worse VR-12 PCS, SF-12 MCS, PROMIS-PF, PHQ-9, VAS-BP, and ODI scores preoperatively (p ≤ 0.014, all), worse VR-12 MCS/PCS, SF-12 MCS, PROMIS-PF, PHQ-9, and ODI scores at 6-week postoperatively (p ≤ 0.039, all), and worse VR-12 MCS, SF-12 MCS, PROMIS-PF, PHQ-9, VAS-BP, VAS-LP, and ODI scores at FF (p ≤ 0.046, all). The VR-12 MCS < 50 cohort showed greater improvement in VR-12 MCS and SF-12 MCS scores at 6 weeks and FF (p ≤ 0.005, all). The VR-12 MCS < 50 cohort experienced greater MCID achievement for VR-12 MCS, SF-12 MCS, and PHQ-9 (p ≤ 0.006, all). CONCLUSION: VR-12 MCS < 50 yielded worse mental health, physical function, pain and disability postoperatively, yet reported greater improvements in magnitude and MCID achievement for mental health.

Does Preoperative Back Pain Impact Patient-reported Outcomes in Patients Undergoing Minimally Invasive Transforaminal Lumbar Interbody Fusion for Isthmic Spondylolisthesis?

STUDY DESIGN: Retrospective review. OBJECTIVE: To determine postoperative clinical outcomes in patients undergoing minimally invasive (MIS) transforaminal lumbar interbody fusion (TLIF) for isthmic spondylolisthesis (IS). BACKGROUND: Few studies have examined the postoperative clinical trajectory in patients undergoing MIS-TLIF specifically for IS. METHODS: Patients were separated into two cohorts based on the previously defined Visual Analog Scale (VAS) back pain (BP) for severe pain: VAS-BP <7 and VAS-BP ≥7. Patient-reported outcome measures (PROMs) of Patient-Reported Outcomes Measurement Information System-physical function (PF), 12-item Short Form (SF-12) Physical/Mental Component Score, Patient Health Questionnaire-9, VAS-BP, VAS leg pain, and Oswestry Disability Index were collected preoperatively and up to 2-year postoperatively. Minimum clinically important difference (MCID) was calculated through previously defined thresholds. RESULTS: A total of 160 patients were recorded, with 58 patients in the VAS-BP <7 cohort. The VAS-BP <7 cohort demonstrated significant improvement in all PROMs at one or more postoperative time points. The VAS-BP ≥7 demonstrated significant improvement at 3 or more postoperative time points in all PROMs except for SF-12 Mental Component Score. The VAS-BP <7 cohort reported significantly superior preoperative and postoperative PROMs in all domains, except for SF-12 Physical Component Score. The VAS-BP ≥7 cohort had higher MCID achievement rates at one or more time points in multiple PROMs. CONCLUSION: Patients undergoing MIS-TLIF for IS demonstrated significant postoperative improvement in PF, mental function, pain, and disability outcomes independent of preoperative severity of BP. Patients with lower preoperative BP demonstrated superior outcomes in PF, mental function, pain, and disability. However, patients with greater preoperative BP achieved higher rates of MCID in mental function, BP, and disability outcomes. Patients with greater severity of preoperative BP undergoing MIS-TLIF for IS may experience greater rates of clinically relevant improvement in mental function, BP, and disability outcomes.

Impact of Preoperative Symptom Duration on Patient-reported Outcomes After Minimally Invasive Transforaminal Interbody Fusion for Degenerative Spondylolisthesis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To assess the impact of preoperative symptom duration (PSD) on patient-reported outcome measures (PROMs) after minimally invasive (MIS) transforaminal lumbar interbody fusion (TLIF) for degenerative spondylolisthesis (DSpond). BACKGROUND: A prolonged duration of preoperative symptoms may implicate inferior long-term outcomes postsurgery. Prior studies of lumbar fusion recipients are limited by the inclusion of heterogeneous populations. METHODS: A single-surgeon registry was retrospectively queried for privately insured patients who had undergone primary, elective, single-level MIS-TLIF for DSpond with a recorded symptom start date. Cohorts were formed by PSD: shorter duration (PSD <1 y) or greater duration (GD; PSD ≥1 y). PROMs evaluated included Patient-reported Outcomes Measurement Information System-Physical Function, Oswestry Disability Index, Visual Analog Scale-Back, Visual Analog Scale-Leg, and 9-item Patient Health Questionnaire. The magnitude of PROM (∆PROM) improvement from preoperative baseline to 6 weeks and final follow-up (∆PROM-FF) were compared between cohorts. Intercohort achievement rates of a minimum clinically important difference in each PROM were compared. RESULTS: A total of 133 patients included 85 patients with GD cohort. There were no significant differences in pre hoc demographics and perioperative characteristics between cohorts, as well as preoperative, 6-week, or final follow-up PROMs between cohorts. Both cohorts demonstrated significant improvement in all PROMs at 6 weeks and final follow-up (P ≤ 0.049, all). There were no significant intercohort differences demonstrated in minimum clinically important difference achievement rates, ∆PROM-6W, or ∆PROM-FF in any PROM. CONCLUSIONS: Regardless of the symptom duration before MIS-TLIF for DSpond, patients demonstrate significant improvement in physical function, pain, disability, and mental health. Patients with a GD of preoperative symptoms did not report inferior scores in any PROM domain. Patients with a GD of preoperative symptoms did not suffer inferior rates of clinically meaningful improvement after surgical intervention. These findings should be considered when counseling patients before surgical intervention for DSpond.

Obesity Does Not Negatively Affect Patient-perceived Outcomes After Cervical Disc Replacement for Disc Herniation.

STUDY DESIGN: Retrospective review. OBJECTIVE: To assess the impact of Body Mass Index (BMI) on patient-reported outcome measures (PROMs) after cervical disc replacement (CDR). BACKGROUND: BMI may affect PROMs after spine surgery. METHODS: Primary CDR recipients for herniated disc(s) with BMI <40 were retrospectively selected from a single-surgeon registry. Cohorts were divided into non-obese (BMI <30) and obese (BMI ≥30). Intercohort in-hospital complication rates were compared through independent samples t tests. Pre/postoperative PROMs were compared between cohorts through multivariable regression accounting for demographic differences. Final follow-up dates between patients averaged 11.8 ± 9.3 months. PROMs assessed included Patient-reported Outcomes Measurement Information System-Physical Function, Neck Disability Index, Visual Analog Scale-Neck, Visual Analog Scale-Arm, and the 9-item Patient Health Questionnaire. Improvements in PROMs were evaluated and compared at each follow-up within cohorts through paired t tests. The magnitude of improvement in PROMs from preoperative baseline at 6-week follow-up (∆PROM-6W) and final follow-up (∆PROM-FF) along with achievement rates of minimum clinically important differences were compared between cohorts through multivariable regression accounting for demographic differences. RESULTS: Of 153 patients, 53 patients were noted as obese. Demographic differences included age, prevalence of hypertension and diabetes, and comorbidity burden scores (P ≤ 0.011, all). No significant variations in in-hospital complications were found. The non-obese cohort demonstrated improvements in all PROMs at 6 weeks and final follow-up periods (P ≤ 0.005, all). The obese cohort demonstrated improvements in all postoperative PROMs besides 9-item Patient Health Questionnaire at 6 weeks (P ≤ 0.015, all). After accounting for age and comorbidity variations, there were no significant intercohort differences in raw PROM scores, ∆PROM-6W, ∆PROM-FF, or minimum clinically important difference achievement rates. CONCLUSIONS: Regardless of BMI, patients experience significant improvements in physical function, disability, pain, and mental health after CDR for disc herniation. Patients with obesity do not suffer inferior patient-perceived outcomes after CDR. These findings may help surgeons counsel patients in the preoperative period.

The Surgical Learning Curve for Cervical Disk Replacement.

STUDY DESIGN: Retrospective study. OBJECTIVE: To characterize an experienced single surgeon learning curve for cervical disk replacement (CDR). SUMMARY OF BACKGROUND DATA: A single surgeon learning curve has not been established for CDR. METHODS: Patients undergoing CDR were included. The cumulative sum of operative time was utilized to separate cases into 3 phases: learning, practicing, and mastery. Demographics, perioperative characteristics, complications, patient-reported outcomes (PROs), and radiographic outcomes were collected preoperatively and up to 1 year postoperatively. PROs included Patient-reported Outcomes Measurement Information System Physical Function, 12-item Short Form-12 Physical Component Score, 12-item Short Form-12 Mental Component Score, visual analog scale (VAS) arm, VAS neck, Neck Disability Index. Radiographic outcomes included segmental angle/segmental range of motion/C2-C7 range of motion. Minimum clinically important difference achievement was determined through a comparison of previously established values. RESULTS: A total of 173 patients were identified, with 14 patients in the learning phase, 42 patients in the practicing phase, and 117 patients in the mastery phase. Mean operative time and mean postoperative day 0 narcotic consumption were significantly higher in the learning phase. The preoperative segmental angle was significantly lower for the learning phase, though these differences were eliminated at the final postoperative time point. Patients in the learning phase reported worse improvement to 6-week postoperative, final postoperative, and worse overall final postoperative VAS Arm scores compared with practicing and mastery phases. CONCLUSIONS: For an experienced spine surgeon, the learning phase for CDR was estimated to span 14 patients. During this phase, patients demonstrated longer operative times, higher postoperative narcotic consumption, and worse postoperative VAS Arm scores. Radiographically, no postoperative differences were noted between different phases of mastery. This single surgeon learning curve demonstrates that CDR may be performed safely and with comparable outcomes by experienced spine surgeons despite decreased operative efficiency in the learning phase.

Medicare procedural costs in ambulatory surgery centers versus hospital outpatient departments for spine surgeries.

OBJECTIVE: Multiple studies have demonstrated the safety of outpatient spine surgery, with reports of equivalent to improved patient outcomes compared with inpatient procedures. This has resulted in the increased use of outpatient surgery over time. However, there remains a paucity of literature evaluating the difference in costs between ambulatory surgery center (ASC)- and hospital outpatient department (HOPD)-based procedures for Medicare beneficiaries. METHODS: Publicly available data from Centers for Medicare & Medicaid Services were accessed via the Medicare Procedure Price Lookup tool. Current Procedural Terminology (CPT) codes were used to identify spine-specific procedures approved for the outpatient setting by CMS. Procedures were grouped into decompression (cervical, thoracic, and lumbar), fusion/instrumentation (cervical, lumbar, and sacroiliac), and kyphoplasty/vertebroplasty cohorts, as well as an overall cohort. Data regarding total costs, facility fees, surgeon reimbursement, Medicare payments, and patient copayments were extracted for each procedure. Descriptive statistics were used to calculate means and standard deviations. Differences between ASC- and HOPD-associated costs were analyzed using the Mann-Whitney U-test. RESULTS: Twenty-one individual CPT codes approved by Medicare for the ASC and/or HOPD setting were identified. Decompression procedures were associated with a significantly lower total cost ($4183 ± $411.07 vs $7583.67 ± $410.89, p < 0.001), facility fees ($2998 ± $0 vs $6397 ± $0, p < 0.001), Medicare payments ($3345.75 ± $328.80 vs $6064.75 ± $328.80, p < 0.001), and patient payments ($835.58 ± $82.13 vs $1515.58 ± $82.13, p < 0.001) in ASCs compared with HOPDs. Fusion/instrumentation procedures had significantly lower facility fees ($10,436.6 ± $2347.51 vs $14,161 ± $2147.07, p = 0.044) and Medicare payments ($9501.2 ± $1732.42 vs $13,757 ± $2037.58, p = 0.009) in ASCs, as well as a trend toward lower total costs ($11,876.8 ± $2165.22 vs $15,601.2 ± $2016.06, p = 0.076). Patient payments in the HOPD setting were significantly lower in the fusion/instrumentation cohort ($1843.6 ± $73.42 vs $2374.4 ± $433.48, p = 0.009). In the kyphoplasty/vertebroplasty cohort, there was no statistically significant difference between ASCs and HOPDs, despite lower overall costs in the ASC for all variables. Surgeon fees were the same regardless of setting for all procedures (p > 0.99). When combining decompression, fusion/instrumentation, and kyphoplasty/vertebroplasty CPT codes into a single cohort, ASC setting was associated with significant cost savings in total cost, facility fees, Medicare payments, and patient payments. CONCLUSIONS: In general, performing spine surgeries in ASCs is associated with cost savings compared with HOPDs. This was demonstrated for decompression and fusion/instrumentation, and kyphoplasty/vertebroplasty Medicare-approved outpatient procedures.

Comparison of clinical outcomes in patients undergoing one- and two-level minimally invasive lumbar microdiscectomy.

OBJECTIVE: Herniated nucleus pulposus (HNP) is one of the most common lumbar spine conditions treated surgically, often through a minimally invasive surgery (MIS) microdiscectomy approach. This technique attempts to reduce damage to the paraspinal muscular-ligamentous envelope. However, there are currently limited data regarding comparative outcomes using patient-reported outcome measures (PROMs) for one- and two-level MIS discectomies. The aim of this study was to quantify comparative clinical outcomes in patients undergoing one-level and two-level MIS lumbar microdiscectomy for HNP using PROMs. METHODS: The authors performed a retrospective review of patients undergoing MIS lumbar microdiscectomy between 2004 and 2019 for the primary diagnosis of HNP at a single academic institution. All patients had a minimum 1-year follow-up. Patient demographics and comorbidities were collected to establish baselines between cohorts. PROMs and minimal clinically important differences (MCIDs) were used to examine the patient's perception of operative success. Bivariate and multivariate linear/logistic regression analyses were used to compare one- and two-level discectomies. The bivariate analysis included the t-test and chi-square test, which were used to assess continuous and categorical variables, respectively. Statistical significance was established at p < 0.05. RESULTS: A total of 293 patients underwent one-level (n = 250) or two-level (n = 43) MIS discectomies. The mean follow-ups for the one- and two-level cohorts were 50.4 (SD 35.5) months and 61.6 (SD 39.8) months, respectively. Fewer female patients underwent two-level discectomies, and BMI and operative duration were higher in the two-level group (p < 0.001). Recurrent herniation requiring reoperation was recorded at rates of 6.80% and 11.6% in the one- and two-level groups, respectively (p = 0.270). Pre- and postoperative PROMs were largely similar between the cohorts; however, patients undergoing one-level discectomy had greater improvement in leg pain, and a significantly greater proportion of these patients achieved MCID for the leg pain visual analog scale score (p < 0.001). CONCLUSIONS: At the 1-year clinical follow-up, patients who underwent two-level discectomy had significantly less improvement in leg pain scores with lower achievement of MCID for leg pain improvement than patients undergoing one-level procedures. At the 1-year follow-up, there were no other significant differences in PROMs between the two cohorts. Given these findings, patients should be counseled regarding the anticipated outcomes to better manage expectations. Further studies are warranted to examine the long-term clinical outcomes associated with single- and multilevel MIS discectomy.

The Effect of Intraoperative Prone Position on Psoas Morphology and Great Vessel Anatomy: Consequences for Prone Lateral Approach to the Lumbar Spine.

BACKGROUND: This study sought to quantify radiographic differences in psoas morphology, great vessel anatomy, and lumbar lordosis between supine and prone intraoperative positioning to optimize surgical planning and minimize the risk of neurovascular injury. METHODS: Measurements on supine magnetic resonance imaging and prone intraoperative computed tomography with O-arm from L2 to L5 levels included the anteroposterior and mediolateral proximity of the psoas, aorta, inferior vena cava (IVC), and anterior iliac vessels to the vertebral body. Psoas transverse and longitudinal diameters, psoas cross-sectional area, total lumbar lordosis, and segmental lordosis were assessed. RESULTS: Prone position produced significant psoas lateralization, especially at more caudal levels (P < 0.001). The psoas drifted slightly anteriorly when prone, which was non-significant, but the magnitude of anterior translation significantly decreased at more caudal segments (P = 0.038) and was lowest at L5 where in fact posterior retraction was observed (P = 0.032). When prone, the IVC (P < 0.001) and right iliac vein (P = 0.005) migrated significantly anteriorly, however decreased anterior displacement was seen at more caudal levels (P < 0.001). Additionally, the IVC drifted significantly laterally at L5 (P = 0.009). Mean segmental lordosis significantly increased when prone (P < 0.001). CONCLUSION: Relative to the vertebral body, the psoas demonstrated substantial lateral mobility when prone, and posterior retraction specifically at L5. IVC and right iliac vein experienced significant anterior mobility-particularly at more cephalad levels. Prone position enhanced segmental lordosis and may be critical to optimizing sagittal restoration.

Antibiotic use in spine surgery: A narrative review based in principles of antibiotic stewardship.

Background: A growing emphasis on antibiotic stewardship has led to extensive literature regarding antibiotic use in spine surgery for surgical prophylaxis and the treatment of spinal infections. Purpose: This article aims to review principles of antibiotic stewardship, evidence-based guidelines for surgical prophylaxis and ways to optimize antibiotics use in the treatment of spinal infections. Methods: A narrative review of several society guidelines and spine surgery literature was conducted. Results: Antibiotic stewardship in spine surgery requires multidisciplinary investment and consistent evaluation of antibiotic use for drug selection, dose, duration, drug-route, and de-escalation. Developing effective surgical prophylaxis regimens is a key strategy in reducing the burden of antibiotic resistance. For treatment of primary spinal infection, the diagnostic work-up is vital in tailoring effective antibiotic therapy. The future of antibiotics in spine surgery will be highly influenced by improving surgical technique and evidence regarding the role of bacteria in the pathogenesis of degenerative spinal pathology. Conclusions: Incorporating evidence-based guidelines into regular practice will serve to limit the development of resistance while preventing morbidity from spinal infection. Further research should be conducted to provide more evidence for surgical site infection prevention and treatment of spinal infections.

The Veterans Rand-12 Physical Composite Score Prognosticates Postoperative Clinical Outcomes in Patients Undergoing Anterior Cervical Discectomy and Fusion.

OBJECTIVE: To determine prognostic value of preoperative Veterans RAND 12-Item Health Survey (VR-12) physical composite score (PCS) on outcomes in patients undergoing anterior cervical discectomy and fusion (ACDF). METHODS: ACDF patients with preoperative VR-12 PCS formed 2 cohorts: VR-12 PCS <35 and VR-12 PCS ≥35. The following patient-reported outcome measures (PROMs) were gathered preoperatively and postoperatively up to 2 years: VR-12 mental composite score (MCS)/PCS, Neck Disability Index (NDI), Patient-Reported Outcomes Measurement Information System (PROMIS) PF, 9-Item Patient Health Questionnaire (PHQ-9), visual analog scale (VAS) neck/arm pain, and 12-Item Short Form Health Survey (SF-12) PCS/MCS. Comparing PROMs change with established thresholds determined achievement of minimum clinically important difference (MCID). Univariate analysis compared demographics, perioperative characteristics, and preoperative PROMs. Multivariable regression analysis compared postoperative PROMs and MCID achievement. RESULTS: Of 174 patients, 83 had VR-12 PCS <35. Preoperatively, patients with reduced PF displayed lower patient-reported outcome scores in NDI, PHQ-9, and SF-12 MCS (P ≤ 0.008), but not in VAS arm. At 6 weeks postoperatively, these patients continued to score lower in NDI (P ≤ 0.014) and SF-12 PCS (P ≤ 0.001), among others. By the final check, most scores remained lower (P ≤ 0.002) except for PHQ-9 and VAS arm (P > 0.05). Greater improvements at 6 weeks postoperatively were especially noted in patients with lower initial VR-12 PCS for NDI, PROMIS PF, and SF-12 PCS (P < 0.05). However, by final follow-up, only PROMIS PF showed noteworthy improvement (P = 0.19). Regarding MCID achievement, significant differences were largely absent except in NDI, where patients with reduced PF exhibited more MCID achievement (P = 0.016). CONCLUSIONS: ACDF patients with VR-12 PCS <35 experienced inferior PF, mental health, and disability postoperatively until final follow-up. There were no significant differences in postoperative improvement magnitude and MCID achievement. Results suggest that baseline VR-12 PCS in ACDF patients may indicate poorer PF, mental health, and disability postoperatively. However, VR-12 PCS does not limit extent of postoperative improvement.