Impact of American Society of Anesthesiologists' Classification on Postoperative Satisfaction and Clinical Outcomes Following Lumbar Decompression: Cohort-Matched Analysis

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The aim was to compare patient-reported outcomes (PROMs), minimum clinically important difference (MCID) achievement, and postoperative satisfaction following minimally invasive lumbar decompression in patients stratified by American Society of Anesthesiologists (ASA) classification.

SUMMARY OF BACKGROUND DATA

Some guidelines recommend against performing elective procedures for patients with an ASA score of 3 or greater; however, long-term postoperative outcomes are not well described.

METHODS

Primary, single-level, minimally invasive lumbar decompression procedures were identified. PROMs were administered at preoperative, 6-week, 12-week, 6-month, 1-year, 2-year timepoints and included Patient-Reported Outcomes Measurement Information System-Physical Function, visual analog scale (VAS) back/leg, Oswestry disability index (ODI), and 12-item short form physical component score. Satisfaction scores were collected postoperatively for VAS back/leg, ODI, and individual ODI subcategories. Patients were grouped (ASA<3, ASA≥3), and propensity scores were matched to control for significant differences. Demographic and perioperative characteristics were compared using χ 2 and the Student's t test. Mean PROMs and postoperative satisfaction were compared at each time point by a 2-sample t test. Postoperative PROM improvement from the preoperative baseline within each cohort was calculated with a paired t test. MCID achievement was determined by comparing ΔPROMs to established thresholds and comparing between groups using simple logistic regression.

RESULTS

One hundred and twenty-nine propensity-matched patients were included: 99 ASA<3 and 30 ASA≥3. No significant demographic differences were observed between groups. ASA≥3 patients experienced significantly increased length of stay and postoperative narcotic consumption on surgery day ( P <0.048, all). Mean PROMs and MCID achievement did not differ. The ASA<3 cohort significantly improved from the preoperative baseline for all PROMs at all postoperative time points. ASA<3 patients demonstrated higher levels of postoperative satisfaction at 6 weeks for VAS leg, VAS back, ODI, sleeping, lifting, walking, standing, sex, travel, and at 6 months for VAS back ( P <0.045, all).

CONCLUSION

ASA≥3 patients may achieve similar long-term clinical outcomes to ASA<3 patients, though they may show poorer short-term satisfaction for disability, leg pain, and back pain, which could be related to differing preoperative expectations.

Anterior Cervical Discectomy and Fusion Versus Cervical Disc Replacement for a Workers' Compensation Population in an Ambulatory Surgical Center

STUDY DESIGN

Retrospective Cohort.

OBJECTIVE

To evaluate patient-reported outcome measures (PROM) and minimal clinically important difference (MCID) achievement outcomes between anterior cervical discectomy and fusion (ACDF) and cervical disk replacement (CDR) in the Workers' Compensation (WC) population.

SUMMARY OF BACKGROUND DATA

No studies to our knowledge have compared PROMs and MCID attainment between ACDF and CDR among patients with WC insurance undergoing surgery in an outpatient ambulatory surgical center (ASC).

METHODS

WC insurance patients undergoing primary, single/double-level ACDF/CDR in an ASC were identified. Patients were divided into ACDF versus CDR. PROMs were collected at preoperative/6-week/12-week/6-month/1-year timepoints, including PROMIS-PF, SF-12 PCS/MCS, VAS neck/arm, and NDI.

RESULTS

Seventy-nine patients were included, 51 ACDF/28 CDR. While operative time (56.4 vs. 54.4 min), estimated blood loss (29.2 vs. 25.9 mL), POD0 pain (4.9 vs. 3.8), and POD0 narcotic consumption (21.2 vs. 14.5 oral morphine equivalents) were higher in ACDF patients, none reached statistical significance ( P >0.050, all). One-year arthrodesis rate was 100.0% among ACDF recipients with available imaging (n=36). ACDF cohort improved from preoperative for PROMIS-PF from 12 weeks to 1 year, SF-12 PCS at 6 months, all timepoints for VAS neck/arm, and 12 weeks/6 months for NDI ( P ≤0.044, all). CDR cohort improved from preoperative for PROMIS-PF at 6 months, VAS neck/arm from 12 weeks to 1 year, and NDI at 12 weeks/6 months ( P ≤0.049, all). CDR cohort reported significantly lower VAS neck at 12 weeks/1 year and VAS arm at 12 weeks ( P ≤0.039, all). MCID achievement rates did not differ.

CONCLUSION

While operative duration/estimated blood loss/acute postoperative pain/narcotic consumption were, on average, higher among ACDF recipients, these were not statistically significant, possibly due to the limited sample size. ACDF and CDR ASC patients generally demonstrated comparable arm pain/disability/physical function/mental health, though neck pain was significantly lower at multiple timepoints among CDR patients. Clinically meaningful PROM improvements were comparable. Larger, multicentered studies are required to confirm our results.

Does Baseline Severity of Arm Pain Influence Outcomes Following Single-Level Anterior Cervical Discectomy and Fusion?

Study Design

Retrospective cohort.

Purpose

To assess preoperative arm pain severity influence on postoperative patient-reported outcomes measures (PROMs) and minimal clinically important difference (MCID) achievement following single-level anterior cervical discectomy and fusion (ACDF).

Overview of Literature

There is evidence that preoperative symptom severity can affect postoperative outcomes. Few have evaluated this association between preoperative arm pain severity and postoperative PROMs and MCID achievement following ACDF.

Methods

Individuals undergoing single-level ACDF were identified. Patients were grouped by preoperative Visual Analog Scale (VAS) arm ≤8 vs. >8. PROMs collected preoperatively and postoperatively included VAS-arm/VAS-neck/Neck Disability Index (NDI)/12-item Short Form (SF-12) Physical Composite Score (PCS)/SF-12 mental composite score (MCS)/Patient-Reported Outcomes Measurement Information System physical function (PROMIS-PF). Demographics, PROMs, and MCID rates were compared between cohorts.

Results

A total of 128 patients were included. The VAS arm ≤8 cohort significantly improved for all PROMs excepting VAS arm at 1-year/2-years, SF-12 MCS at 12-weeks/1-year/2-years, and SF-12 PCS/PROMIS-PF at 6-weeks, only (p ≤0.021, all). The VAS arm >8 cohort significantly improved for VAS neck at all timepoints, VAS arm from 6-weeks to 1-year, NDI from 6-weeks to 6-months, and SF-12 MCS/PROMIS-PF at 6-months (p ≤0.038, all). Postoperatively, the VAS arm >8 cohort had higher VAS-neck (6 weeks/6 months), VAS-arm (12 weeks/6 months), NDI (6 weeks/6 months), lower SF-12 MCS (6 weeks/6 months), SF-12 PCS (6 months), and PROMISPF (12 weeks/6 months) (p ≤0.038, all). MCID achievement rates were higher among the VAS arm >8 cohort for the VAS-arm at 6-weeks/12-weeks/1-year/overall and NDI at 2 years (p ≤0.038, all).

Conclusions

Significance in PROM score differences between VAS arm ≤8 vs. >8 generally dissipated at the 1-year and 2-year timepoint, although higher preoperative arm pain patients suffered from worse pain, disability, and mental/physical function scores. Furthermore, clinically meaningful rates of improvement were similar throughout the vast majority of timepoints for all PROMs studied.

The Influence of Presenting Physical Function on Postoperative Patient Satisfaction and Clinical Outcomes Following Minimally Invasive Lumbar Decompression

STUDY DESIGN

The study of retrospective cohort.

OBJECTIVE

The aim was to compare patient-reported outcome measures (PROMs), satisfaction, and minimum clinically important difference (MCID) achievement following minimally invasive lumbar decompression (MIS-LD) in patients stratified by the preoperative patient-reported outcomes measurement information system physical function (PROMIS-PF) score.

SUMMARY OF BACKGROUND DATA

Although prior studies have assessed the predictive utility of preoperative PROMIS-PF scores on patient outcomes in spinal fusion, its utility has not been studied for patients undergoing MIS-LD.

METHODS

Primary, single/multilevel MIS-LD procedures were identified. PROMs were administered at preoperative/6-week/12-week/6-month/1-year/2-year time points and included PROMIS-PF/visual analog scale (VAS) back and leg/Oswestry Disability Index (ODI). Satisfaction scores were collected postoperatively. The patients were grouped by preoperative PROMIS-PF score (≤35, >35), with higher scores indicating improved physical function. Demographic/perioperative characteristics were compared using χ 2 /Student t test. Mean PROMs/postoperative satisfaction was compared utilizing 2-sample t test. Postoperative PROM improvement from preoperative was calculated with paired t tests. MCID achievement rates were compared using simple logistic regression.

RESULTS

Two hundred and sixteen patients were included, 58 PROMIS-PF≤35 and 158 PROMIS-PF>35. Ethnicity/insurance differed ( P ≤0.004, all). Hospital length of stay was greater for PROMIS-PF>35 ( P =0.042). All preoperative mean PROMs significantly differed except for VAS Back. Several postoperative mean PROMs differed: PROMIS-PF at 6 weeks/12 weeks/6 months/1 year, SF-12 PCS at 6 weeks/12 weeks/1 year, VAS Back at 6 weeks/12 weeks, VAS leg at 6 weeks/12 weeks, and ODI at 6 weeks/12 weeks ( P <0.050, all). All PROMs significantly improved from preoperative at all postoperative time points ( P <0.003, all). The MCID achievement rates differed only for VAS back for 6 weeks, favoring PROMIS-PF>35 cohort ( P =0.001). Postoperative satisfaction was greater in PROMIS-PF>35 cohort for VAS leg at 6 weeks/12 weeks/6 months/2 years, VAS back at 6-weeks/12-weeks, and ODI at all time points ( P <0.037, all). Postoperative satisfaction was greater in PROMIS-PF>35 cohort for individual ODI categories: sleep at 6-weeks/12-weeks/1-year/2-years, lifting, walking, standing, and travel at all time points, and sexual at 6-weeks/12-weeks/1-year/2-years ( P <0.030, all).

CONCLUSION

Poorer preoperative PROMIS-PF scores were associated with worse postoperative clinical outcomes and satisfaction. By stratifying patients with preoperative PROMIS-PF scores, surgeons may better predict postoperative clinical improvement and seek to manage patient expectations.

Validation of Neck Disability Index Severity among Patients Receiving One or Two-Level Anterior Cervical Surgery

STUDY DESIGN

Retrospective cohort.

PURPOSE

To evaluate the validity of established severity thresholds for Neck Disability Index (NDI) among patients undergoing anterior cervical discectomy and fusion (ACDF) or cervical disc arthroplasty (CDA).

OVERVIEW OF LITERATURE

Few studies have examined the validity of established NDI threshold values among patients undergoing ACDF or CDA.

METHODS

A surgical database was reviewed to identify patients undergoing cervical spine procedures. Demographics, operative characteristics, comorbidities, NDI, Visual Analog Scale (VAS), and 12-item Short Form (SF-12) physical and mental composite scores (PCS and MCS) were recorded. NDI severity was categorized using previously established threshold values. Improvement from preoperative scores at each postoperative timepoint and convergent validity of NDI was evaluated. Discriminant validity of NDI was evaluated against VAS neck and arm and SF-12 PCS and MCS.

RESULTS

All 290 patients included in the study demonstrated significant improvements from baseline values for all patient-reported outcome measures (PROMs) at all postoperative timepoints (p<0.001) except SF-12 MCS at 2 years (p =0.393). NDI showed a moderate- to-strong correlation (r≥0.419) at most timepoints for VAS neck, VAS arm, SF-12 PCS, and SF-12 MCS (p<0.001, all). NDI severity categories demonstrated significant differences in mean VAS neck, VAS arm, SF-12 PCS, and SF-12 MCS at all timepoints (p<0.001, all). Differences between NDI severity groups were not uniform for all PROMs. VAS neck values demonstrated significant intergroup differences at most timepoints, whereas SF-12 MCS showed significantly different values between most severity groups.

CONCLUSIONS

Neck disability is strongly correlated with neck and arm pain, physical function, and mental health and demonstrates worse outcomes with increasing severity. Previously established severity categories may be more applicable to pain than physical function or mental health and may be more uniformly applied preoperatively for cervical spine patients.

Impact of Postoperative Length of Stay on Patient-Reported and Clinical Outcomes After Anterior Lumbar Interbody Fusion

BACKGROUND

Existing literature has not yet evaluated the impact of postoperative length of stay (LOS) on patient-reported outcome measures (PROMs) and minimum clinically important difference (MCID) in patients undergoing anterior lumbar interbody fusion (ALIF). The authors investigates the influence of postoperative LOS following ALIF on PROMs and MCID achievement rates.

METHODS

A single-surgeon database was retrospectively reviewed for patients undergoing single-level ALIF. The following 2 cohorts were studied: patients with LOS <45 hours and patients with LOS ≥45 hours. The following PROMs were recorded at preoperative and 6-week, 12-week, 6-month, 1-year, and 2-year postoperative timepoints: visual analog scale (VAS) back and leg, Oswestry Disability Index (ODI), 12-item short form (SF-12) physical composite score (PCS), and patient-reported outcome measurement information system physical function. MCID achievement was compared by LOS grouping using χ ² analysis. The rates of complications by LOS grouping and the relative risk among demographic and perioperative characteristics for a longer hospital stay of ≥45 hours were calculated.

RESULTS

A total of 52 subjects were included in each cohort. LOS ≥45 hours demonstrated worse ODI at 6 weeks and SF-12 PCS preoperative and at 12 weeks (P ≤ 0.026, all). LOS <45 hours demonstrated greater MCID rates for all PROMs except VAS back (P ≤ 0.004, all). Postoperative urinary retention (POUR), fever, and total complications (P ≤ 0.003, all) were associated with increased LOS. Diabetes (P = 0.037), preoperative VAS neck ≥7 (P = 0.012), and American Society of Anesthesiologists classification ≥2 (P = 0.003) served as preoperative risk factors for postoperative stay ≥45 hours.

CONCLUSION

Following single-level ALIF, patients with shorter LOS demonstrated significantly greater overall MCID achievement for most PROMs. POUR, fever, and total complications were associated with longer LOS and greater blood loss. Diabetes and higher preoperative leg pain were identified as risk factors for longer LOS.

CLINICAL RELEVANCE

Patients undergoing ALIF with shorter LOS had greater MCID achievement for disability, physical function, and leg pain outcomes. Patients with greater preoperative leg pain and diabetes may be at risk for longer LOS.

LEVEL OF EVIDENCE: 3

Multimodal analgesic protocol for cervical disc replacement in the ambulatory setting: Clinical case series

Background

Effective pain management is paramount for outpatient surgical success. This study aims to report a case series of patients undergoing cervical disc replacement (CDR) in an ambulatory surgery center (ASC) with the use of an enhanced multimodal analgesic (MMA) protocol.

Methods

Primary, single-/2-level CDR procedures at an ASC with an enhanced MMA protocol were included. ASC patients were discharged day of surgery. Patient-reported outcome measures (PROMs) were administered at preoperative/6-week/12-week/6-month/1-year/2-year timepoints and included Visual Analogue Scale (VAS) neck, VAS arm, Neck Disability Index (NDI), Patient-Reported Outcomes Measurement Information System-Physical Function (PROMIS-PF), and 12-Item Short-Form Physical and Mental Composite Score (SF-12 PCS/SF-12 MCS). A t-test assessed postoperative PROM improvement from baseline. MCID achievement was determined by comparing ΔPROM scores to previously established thresholds.

Results

106 patients were included, 76 single-level and 30 2-level. Most single-levels occurred at C5-C6, most 2-levels at C5-C7. One 2-level patient developed a hematoma 5 days postoperatively and underwent revision for evacuation. Five patients reported postoperative dysphagia; all were quickly resolved. One patient had an episode of seizure secondary to serotonin syndrome from concealed drug use. Patient was reintubated, transferred, and treated for serotonin syndrome. Two patients experienced postoperative nausea/vomiting. Cohort significantly improved from baseline for all PROMS at all timepoints except SF-12 MCS at 1-year/2-years and SF-12 PCS at 2 years (p < 0.047, all). Overall MCID achievement rates were: VAS arm (48.7%), VAS neck (69.1%), NDI (98.9%), SF-12 MCS (50.0%), SF-12 PCS (54.6%), and PROMIS-PF (73.4%).

Conclusion

Outpatient CDR, incorporating an enhanced MMA protocol, can be safely and effectively performed with proper patient selection and surgical technique. Patients saw timely discharge, well-controlled postoperative pain, and favorable long-term outcomes.

Impact of Gender on Postsurgical Outcomes in Patients Undergoing Anterior Cervical Discectomy and Fusion

BACKGROUND

Prior studies associate male gender with higher complication rates following anterior cervical discectomy and fusion (ACDF), but none has investigated gender influence on patient-reported outcome measures (PROMs) and minimal clinically important difference (MCID) following single-level ACDF.

METHODS

Patients undergoing primary, single-level ACDF were divided into female and male groups. Visual analog scale (VAS) neck/arm, Neck Disability Index (NDI), 12-item short form (SF-12) physical composite score (PCS), PROM information system physical function (PROMIS-PF), and veterans RAND 12-item (VR-12) health survey PCS were collected preoperatively and postoperatively. Simple linear regression analysis evaluated the predictive capability of gender on PROMs. Multiple regression analysis was performed to determine the effects of gender on mean PROMs while accounting for insurance type. Established MCID values determined achievement rates across PROMs. χ ² analysis compared MCID achievement by gender.

RESULTS

A total of 179 women and 134 men were included. Cohorts differed in insurance type, length of stay, and discharge day (P ≤ 0.017, all). Women improved in PROMs at all timepoints (P ≤ 0.049, all) except SF-12 PCS 6 weeks and PROMIS-PF 6 weeks. Men improved in PROMs at all timepoints (P ≤ 0.042) except VAS arm 2 years, SF-12 PCS 6 weeks and 2 years, PROMIS-PF 6 weeks, and VR-12 PCS 6 weeks. Women demonstrated higher SF-12 PCS (P = 0.043) and VR-12 PCS (P = 0.035) 2 years. Multiple regression determined that VAS neck and arm from 6 weeks to 6 months, NDI from preoperative to 6 months, SF-12 PCS and VR-12 PCS from preoperative to 12 weeks, and PROMIS-PF preoperative, 6 weeks, and 6 months were significantly affected by gender and insurance status (P ≤ 0.031, all). MCID achievement rate did not differ for any PROM between genders.

CONCLUSION

Women reported significantly higher long-term physical function health (SF-12 PCS and VR-12 PCS) compared with men, while disability and pain did not differ. Nevertheless, no significant differences in MCID achievement were observed for any PROM studied. Gender does not appear to play a significant role in clinically meaningful recovery following single-level ACDF.

CLINICAL RELEVANCE

Gender has little value in prognostication for determining clinically meaningful recovery after single-level ACDF.

LEVEL OF EVIDENCE: 3

Minimally Invasive Transforaminal versus Anterior Lumbar Interbody Fusion in Patients Undergoing Revision Fusion: Clinical Outcome Comparison

OBJECTIVE

We aim to compare perioperative/postoperative clinical outcomes between minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and anterior lumbar interbody fusion (ALIF) in patients presenting for revision surgery.

METHODS

A retrospective database was reviewed for procedures between November 2005 and December 2021. Revision MIS-TLIF/ALIFs were included, whereas primary fusions or diagnosis of infection/malignancy/trauma were excluded. Patients were grouped into MIS-TLIF/ALIF cohorts. Preoperatively/postoperatively collected patient-reported outcome measures (PROMs) included visual analog scale back/leg score, Oswestry Disability Index, Patient-Reported Outcome Measurement Information System-Physical Function (PROMIS-PF), and Short-Form 12-Item Survey Mental/Physical Composite Scores.

RESULTS

A total of 164 patients were eligible, with 84 patients in the MIS-TLIF cohort. The presence of degenerative spondylolisthesis and central stenosis, narcotic consumption on postoperative day 0/1, and postoperative urinary retention rates was greater in the MIS-TLIF cohort (P ≤ 0.036, all). Preoperative PROMs between cohorts did not significantly differ. Significantly favorable postoperative PROM scores were shown in the MIS-TLIF cohort with PROMIS-PF at 12 weeks/6 months (P ≤ 0.033, all). Most patients in both cohorts achieved overall minimum clinically important difference for visual analog scale back/leg score, Oswestry Disability Index, Short-Form 12-Item Survey Physical Composite Score, and PROMIS-PF. No differences were noted between cohorts within rates of MCID achievement.

CONCLUSIONS

Patients undergoing revision fusion via MIS-TLIF or ALIF reported similar 1-year postoperative mean outcomes and rates of meaningful clinical achievement for physical function, mental health, disability, and back/leg pain. However, patients undergoing revision MIS-TLIF reported improved physical function at 12 weeks and 6 months. Perioperatively, patients undergoing revision MIS-TLIF were noted to consume significantly greater quantities of narcotics.

History of Prior Lumbar Surgery Does Not Impact Mental Health Outcomes Following Anterior Cervical Discectomy and Fusion

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

The objective of this study was to evaluate the impact of undergoing a prior lumbar procedure on mental health outcomes following anterior cervical discectomy and fusion.

SUMMARY OF BACKGROUND DATA

Revision and reoperations are perceived as risk factors for worse mental health outcomes.

METHODS

A retrospective review of a surgical database was performed for cervical and lumbar procedures. The mental health measures used were: Short Form 12-Item Mental Composite Score (SF-12 MCS) and Patient Health Questionnaire 9 (PHQ-9). Secondary outcomes of interest were Visual Analogue Scale for neck and arm pain, Neck Disability Index, and Short Form 12-Item Physical Composite Score (SF-12 PCS). All outcomes were collected preoperatively and at 6 weeks, 12 weeks, 6 months, and 1 year postoperatively. Minimum clinically important difference (MCID) was calculated using established values. Patients were grouped based on the surgical history of an elective lumbar spine procedure and propensity-matched. Differences in postoperative outcome scores and MCID achievement were evaluated using linear and logistic regression respectively.

RESULTS

A total of 74 patients were included in this study. Mental health outcomes did not demonstrate significant differences between groups for SF-12 MCS and PHQ-9 for all time points except at 6 weeks for PHQ-9 ( P =0.038). MCID achievement was not significantly impacted by surgical history for all outcome measures at all postoperative time points (all P >0.050). The majority of patients achieved an MCID by the 1-year time point for all outcomes for patients without a prior lumbar surgery except for Visual Analogue Scale arm and SF-12 PCS, while those with a surgical history achieved an MCID for all outcomes except SF-12 PCS and PHQ-9.

CONCLUSIONS

Anterior cervical discectomy and fusion patients with a past history of lumbar surgery demonstrated significant improvements in depression, neck and arm pain, disability, and physical function as those without a past lumbar surgical history. Prior surgery also did not impact MCID achievement for all outcomes.

Comparing Patient-Reported Outcomes in Patients Undergoing Lumbar Fusion for Isthmic Spondylolisthesis with Predominant Back Pain versus Predominant Leg Pain Symptoms

OBJECTIVE

To compare patient-reported outcome measures (PROMs) and minimum clinically important difference (MCID) achievement following anterior or transforaminal lumbar interbody fusion for isthmic spondylolisthesis in patients presenting with predominant back pain versus predominant leg pain symptoms.

METHODS

A single-surgeon database was reviewed for anterior or transforaminal lumbar interbody fusion procedures for isthmic spondylolisthesis. Patient demographics, perioperative characteristics, postoperative complications, and PROMs were collected. Demographic/perioperative characteristics were compared among groups using χ² and Student t tests for categorical and continuous variables, respectively. Mean PROM scores were compared using an unpaired Student t test. Postoperative improvement from preoperative baseline within each cohort was assessed with paired-samples t test. MCID achievement rates were compared with χ² analysis.

RESULTS

In total, 143 patients were included with 65 patients in the predominant back pain and 78 patients in the predominant leg pain cohort. Preoperative visual analog scale (VAS) leg was noted to be significantly greater in predominant leg pain cohort (P < 0.001). Cohorts demonstrated significant mean postoperative differences for the following PROMs at the following postoperative time points: significant differences were noted between cohorts for rate of achievement of MCID for the following PROMs at the following time points: VAS back at 2 years and VAS leg at 6 weeks/12 weeks/6 months/overall (P < 0.036, all).

CONCLUSIONS

Compared with patients presenting for surgery with predominant leg pain symptoms, patients undergoing lumbar fusion at L4-L5 and L5-S1 for isthmic spondylolisthesis with predominant back pain symptoms may demonstrate improved long-term clinical outcomes for reported back pain, leg pain, and disability and reduced postoperative length of stay and narcotic consumption.

Management of lymphocele following anterior lumbar interbody fusion, case report and review of literature

While anterior lumbar interbody fusion (ALIF) is known as an established and safe procedure for treatment of degenerative disc disease, albeit rare, the development of postoperative intra-abdominal or retroperitoneal collection of lymph warrants timely diagnosis and management. This study presents the case of a 62-year-old male who underwent L4-L5 and L5-S1 ALIF and developed a persistent left-sided fluid collection, resulting in a symptomatic retroperitoneal lymphocele confirmed by computed tomography (CT). After percutaneous drainage by interventional radiology (IR), output remained high at 1 liter (L) per day, necessitating sclerotherapy with doxycycline and ethanol. In the absence of improvement, a lymphangiogram demonstrating a persistent lymph leak and glue embolization was performed. Due to refractory symptoms, retroperitoneal exploration with methylene blue dye was utilized for lymphatic mapping, and a lymphatic capillary leak in proximity to the left iliac artery was identified and successfully ligated with resolution of symptoms. With suspected fluid collections following ALIF, confirmation with CT or ultrasound (US) imaging followed by percutaneous drainage and testing of fluid is necessary. In mild cases, drainage alone or nonsurgical chemical sclerotherapy may suffice. In symptomatic refractory cases, localization of the site with lymphangiogram or US-guided injection of methylene blue dye allows for easier identification and definitive management with either transabdominal laparoscopic fenestration or retroperitoneal surgical exploration and ligation.

History and Evolution of the Minimally Invasive Transforaminal Lumbar Interbody Fusion

The minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is a popular surgical technique for lumbar arthrodesis, widely considered to hold great efficacy while conferring an impressive safety profile through the minimization of soft tissue damage. This elegant approach to lumbar stabilization is the byproduct of several innovations throughout the past century. In 1934, Mixter and Barr's paper in the New England Journal of Medicine elucidated the role of disc herniation in spinal instability and radiculopathy, prompting surgeons to explore new approaches and instruments to access the disc space. In 1944, Briggs and Milligan published their novel technique, the posterior lumbar interbody fusion (PLIF), involving continuous removal of vertebral bone chips and replacement of the disc with a round bone peg. The following decades witnessed several PLIF modifications, including the addition of long pedicle screws. In 1982, Harms and Rolinger sought to redefine the posterior corridor by approaching the disc space through the intervertebral foramen, establishing the transforaminal lumbar interbody fusion (TLIF). In the 1990s, lumbar spine surgery experienced a paradigm shift, with surgeons placing increased emphasis on tissuesparing minimally invasive techniques. Spurred by this revolution, Foley and Lefkowitz published the novel MIS-TLIF technique in 2002. The MIS-TLIF has demonstrated comparable surgical outcomes to the TLIF, with an improved safety profile. Here, we present a view into the history of the posterior-approach treatment of the discogenic radiculopathy, culminating in the MIS-TLIF. Additionally, we evaluate the hallmark characteristics, technical variability, and reported outcomes of the modern MIS-TLIF and take a brief look at technologies that may define the future MIS-TLIF.

The Effect of the Preoperative Severity of Neck Pain on Patient-Reported Outcome Measures and Minimum Clinically Important Difference Achievement After Anterior Cervical Discectomy and Fusion

OBJECTIVE

To compare patient-reported outcome measure (PROM) scores and minimum clinically important difference (MCID) achievement rates among patients undergoing single-level anterior cervical discectomy and fusion (ACDF) in patients with varying severity of preoperative visual analog scale (VAS) neck score.

METHODS

Patients with ACDF were grouped: severity of preoperative VAS neck score ≤8 or >8. Demographic/perioperative variables and PROMs (Patient-Reported Outcomes Measurement Information System Physical Function [PROMIS PF] score, 12-Item Short Form [SF-12] Mental Component Score [MCS], VAS neck/arm score, and Neck Disability Index [NDI]) were collected preoperatively/postoperatively. MCID attainment comparison by grouping was evaluated using χ² analysis.

RESULTS

A total of 137 patients were included (103 VAS neck preoperative score ≤8; 34 VAS neck preoperative score >8). The VAS neck preoperative score ≤8 cohort did not improve: 6 weeks PROMIS-PF score, 6 weeks SF-12 Physical Component Score [PCS], 12 weeks/1 year/2 years SF-12 MCS, 2 years VAS neck score, and 1 years/2 years VAS arm score (P ≤ 0.015, all). VAS neck preoperative score >8 did not improve: 6 weeks/12 weeks/2 years PROMIS-PF score, all time points SF-12 PCS, 6 weeks/12 weeks/1 year/2 years SF-12 MCS, and 2 years VAS arm score (P ≤ 0.013, all). VAS neck preoperative score >8 had inferior PROMIS-PF scores all time points except 1 year (P ≤ 0.036, all), lower SF-12 PCS 6 weeks/6 months (P ≤ 0.043, both), inferior SF-12 MCS at preoperative to 6 months (P ≤ 006, all), higher VAS neck score from preoperative to 6 months (P ≤ 0.018), higher VAS arm score preoperative/12 weeks/6 months (P ≤ 0.020, all), and higher NDI at preoperative/12 weeks/6 months (P ≤ 0.030, all). MCID attainment rates for VAS neck preoperative score >8 were greater for NDI 2 years (P = 0.040), lower for PROMIS-PF score 2 years, and overall (P = 0.018), lower for SF-12 MCS 12 weeks (P = 0.046), lower for VAS neck score 12 weeks to 1 year and overall (P ≤ 0.032, all), and lower for VAS arm score 6 weeks/1 year (P ≤ 0.030, both).

CONCLUSIONS

Patients with single-level ACDF presenting with greater baseline neck pain showed poorer physical function/pain/disability/mental health at preoperative/intermediate postoperative time points, but had comparable long-term PROMs by 2 years. MCID attainment was lower among patients with greater preoperative neck pain; MCID among the VAS neck score >8 cohort were only significantly inferior for neck pain.

Influence of Preoperative Severity on Postoperative Improvement Among Patients With Myeloradiculopathy Following Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The aim was to determine how neck pain and disability improve following anterior cervical discectomy and fusion among patients with myeloradiculopathy.

SUMMARY OF BACKGROUND DATA

Neck pain and disability have traditionally been assessed using the neck disability index (NDI) and visual analog scale (VAS). Few studies have investigated how neck pain/disability improve differently among patients with symptoms of both myelopathy and radiculopathy.

METHODS

Patients were identified through retrospective review of a prospective surgical database from 2013 to 2020. Patient-reported outcome measures (PROMs) collected included VAS neck and arm, NDI, 12-Item Short Form physical composite score (SF-12 PCS), Patient-Reported Outcomes Measurement Information System physical function (PROMIS PF), and Patient Health Questionnaire 9 (PHQ-9). PROMs were collected preoperatively and up to 1-year postoperatively. Patients were categorized by preoperative symptom severity: high VAS arm (>7); high NDI (>55); high VAS arm and NDI; and moderate symptoms. Linear and logistic regression evaluated the impact of preoperative symptom severity on PROM scores and achievement of minimum clinically important difference (MCID), respectively.

RESULTS

A total of 187 patients were included, 98 with neither high VAS arm nor NDI (moderate group), 14 with high NDI, 46 with high VAS arm, and 29 with high NDI and VAS arm. Postoperatively, greater symptom severity was a significant predictor of VAS neck (all timepoints; P ≤0.002, all), VAS arm (6 weeks; P =0.007), NDI (6 weeks to 6 months; P <0.001, all), SF-12 PCS (6 months; P =0.004), P ROMIS PF (6 weeks; P =0.007), and PHQ-9 (6 weeks to 6 months; P <0.001, all). Mean postoperative improvement was different among the four severity groups for VAS arm, NDI, and VAS neck (except for 1-year) ( P ≤0.002, all). Overall MCID achievement rates were significantly greater among higher symptom severity groups across VAS arm and NDI ( P ≤0.003, both).

CONCLUSION

PROM improvement and MCID achievement for NDI, VAS neck, and VAS arm differed based on symptom severity.

Risk Assessment of Anterior Lumbar Interbody Fusion Access in Degenerative Spinal Conditions

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

Develop an evidence-based preoperative risk assessment scoring system for patients undergoing anterior lumbar interbody fusion (ALIF).

SUMMARY OF BACKGROUND DATA

ALIF may hold advantages over other fusion techniques in sagittal restoration and fusion rates, though it introduces unique risks to vascular and abdominal structures and thus possibly increased risk of operative morbidity.

METHODS

Primary, 1 or 2-level ALIFs were identified in a surgical registry. Baseline characteristics were recorded. Axial magnetic resonance imagings at L4-L5 and L5-S1 were reviewed for vascular confluence/bifurcation or anomalous structures, and measured for operative window size/slope. To assess favorable outcomes, a clinical grade was calculated: (clinical grade=blood loss×operative duration), higher value indicating poorer outcome. To establish a risk scoring system, a base risk score algorithm was established and stratified into 5 categories: high, high to intermediate, intermediate, intermediate to low, and low. Modifiers to base risk score included age, body mass index, operative level, history of bone morphogenic protein use, calcified vasculature, spondylolisthesis grade, working window size and slope, and abnormal vasculature. Modifiers were weighted for contribution to surgical risk. A total risk score was calculated and evaluated for strength of association with clinical outcome grades by Pearson correlation coefficient.

RESULTS

A total of 65 patients were included. Mean clinical outcome grade was 5.6, mean total risk score 21.3±21.5. Multilevel procedures (L4-S1) mean total risk score was 57.3±7.8. L4-L5 mean total risk score was 23.6±5.2; L5-S1 mean total risk score 8.3±6.6. Correlation analysis demonstrated a significant and strong relationship (| r |=0.753; P <0.001) between total risk scores and clinical outcome grades.

CONCLUSION

Calculated ALIF risk scores significantly correlated with operative duration and blood loss. This scoring system represents a potential framework to facilitate clinical decision-making and risk assessment for potential ALIF candidates with degenerative spinal pathologies.

Predicting Acute Changes in Depressive Symptoms Following Lumbar Decompression

BACKGROUND

While depressive symptoms improve for most patients following minimally invasive lumbar decompression (MIS LD), for some, symptoms may worsen. This study aimed to investigate predictors of change in depressive symptoms in the short-term postoperative period following MIS LD.

METHODS

We retrospectively analyzed a prospective surgical database for patients undergoing primary MIS LD procedures from 2016 to 2020. Preoperative pain (visual analog scale back and leg) scores were recorded, and the 9-Item Patient Health Questionnaire (PHQ-9) was administered at the preoperative and postoperative (6 weeks, 12 weeks, 6 months, and 1 year) timepoints. Patients were grouped into 1 of 3 categories of depression severity based on preoperative PHQ-9 scores: minimal (0-4), mild (5-9), and moderate to severe (10-27). Postoperative change in depressive symptoms was calculated by determining differences from baseline scores to scores at 6 weeks, 12 weeks, and 6 months. Analysis of demographics, perioperative characteristics, and spinal pathologies was conducted using χ ² test. Significant factors contributing to postoperative changes in depression were analyzed using multiple linear regression analysis. Significance was set at P = 0.05.

RESULTS

The 216 patients included had a mean age of 48 years, and a majority were men (70.4%). Most patients had a preoperative diagnosis of spinal stenosis (90.3%) or herniated nucleus pulposus (69.9%). Univariate analysis identified age, ethnicity, insurance, and diabetes as significant variables among depression severity groups. Patients demonstrated significant improvements in depressive symptoms at all postoperative timepoints (P < 0.001). Multivariate analysis identified several significant predictors of postoperative change in PHQ-9, which included moderate to severe preoperative depression for all postoperative timepoints (all P ≤ 0.038), mild preoperative depression for 6 weeks and 12 weeks (both P ≤ 0.029), and private insurance (P = 0.002) and smoking status (P = 0.047) at 12 weeks.

CONCLUSION

Depression improved at all postoperative timepoints following LD. Insurance type, smoking status, and preoperative depression severity were all identified as significant predictors of postoperative changes in depressive symptoms.

CLINICAL RELEVANCE

This study explores predictors of changes in depressive symptoms following LD.

LEVEL OF EVIDENCE: 3

Dysphagia May Attenuate Improvements in Postoperative Outcomes Following Anterior Cervical Discectomy and Fusion

BACKGROUND

Past studies outline potential risk factors for dysphagia following anterior cervical discectomy and fusion (ACDF). Few studies explored the impact of dysphagia, as measured by the swallowing quality of life (SWAL-QOL), on postoperative patient-reported outcome measure (PROM) improvement. This study aimed to determine the relationship between dysphagia and improvement in pain, disability, physical function, and mental health following ACDF.

METHODS

A retrospective review of patients undergoing primary 1- or 2-level ACDF was performed. Individuals without a completed preoperative SWAL-QOL were excluded. Outcomes were collected for visual analog scale (VAS) neck and arm pain, Neck Disability Index (NDI), Patient-Reported Outcome Measurement Information System Physical Function (PROMIS-PF), 12-Item Short Form Physical Component Score (SF-12 PCS), 9-Item Patient Health Questionnaire (PHQ-9), and SWAL-QOL. Postoperative improvement from preoperative values was evaluated using a paired t test. The impact of SWAL-QOL on each PROM was assessed using linear regression.

RESULTS

A total of 91 patients were included. Mean preoperative SWAL-QoL was 90.4, which worsened at 6 weeks and resolved by 6 months (P ≤ 0.007, both). VAS neck and arm scores significantly improved postoperatively (P < 0.001), as did the NDI score (P < 0.001). Physical function significantly improved at 12 weeks and 6 months (P ≤ 0.021, both). Depressive symptoms improved at 6 weeks and 12 weeks (P ≤ 0.007, both). Preoperatively, SWAL-QOL demonstrated significant relationships with all PROMs (P ≤ 0.005, all). At 6 weeks, 12 weeks, and 6 months (P ≤ 0.048, all), SWAL-QoL again demonstrated a similar significant association with all PROMs. Multiple regression did not demonstrate common demographic or operative variables that were significant predictors of PROMs.

CONCLUSION

Following ACDF, patients experienced a worsening of dysphagia but resolved by 12 weeks. All PROMs demonstrated significant improvements by the 6-month timepoint, except for PHQ-9. SWAL-QoL demonstrated a significant effect on all postoperative outcomes, which may suggest that this questionnaire could effectively evaluate dysphagia and predict positive or negative outcomes following ACDF.

LEVEL OF EVIDENCE

3 CLINICAL RELEVANCE: The severity of dysphagia has a significant association with pain, disability, mental health, and physical function patient-reported outcome measures in patients undergoing ACDF.

Anterior Cervical Discectomy and Fusion Results in Clinically Significant Improvements in Patients With Preoperative Sleep Difficulties

BACKGROUND

Individual items within the Patient Health Questionnaire-9 (PHQ-9) have not been assessed as predictors of postoperative outcomes. Our objective is to study the relationship between responses to individual PHQ-9 items and achievement of a minimum clinically important difference (MCID) following anterior cervical discectomy and fusion (ACDF).

METHODS

A prospective surgical database was reviewed for primary, single-level ACDF procedures performed for degenerative spinal pathology. Patient demographics, preoperative spinal pathology, and perioperative characteristics were recorded. Patient-reported outcome measures (PROMs) including PHQ-9, visual analog scale (VAS) neck and arm, Neck Disability Index, 12-item Short Form physical component score (SF-12 PCS), and Patient-Reported Outcomes Measurement Information System Physical Function were administered at preoperative and 6-week, 12-week, 6-month, 1-year, and 2-year postoperative timepoints. MCID achievement was determined by comparing postoperative PROM improvement from baseline to previously established values. Logistic regression assessed responses to each individual question of the preoperative PHQ-9 as predictors of MCID achievement in each other PROMs.

RESULTS

Sixty-six ACDF patients were included with a mean age of 47.2 years. Herniated nucleus pulposus was the most common preoperative spinal diagnosis (95.6%). The mean operative duration was 50.3 minutes, the mean estimated blood loss was 27.5 mL, and most patients were discharged on postoperative day 0 (81.8%). A majority of patients achieved MCID for all measures except SF-12 PCS. PHQ-9 question 3 significantly predicted MCID achievement for VAS neck (P = 0.045), VAS arm (P = 0.049), and SF-12 PCS (P = 0.037). No other PHQ-9 items or overall PHQ-9 scores significantly predicted MCID achievement.

CONCLUSION

Question 3 of the PHQ-9 regarding "trouble falling asleep, staying asleep, or sleeping too much" significantly predicted clinically meaningful improvement in neck pain, arm pain, and physical function following ACDF, although overall PHQ-9 scores did not. Providers should inform patients experiencing significant sleep-related difficulties that they may be especially likely to benefit from ACDF surgery.

CLINICAL RELEVANCE

Evaluation of sleep from the PHQ-9 predicts clinically relevant improvement in neck pain, arm pain, and physical function in patients undergoing ACDF.

LEVEL OF EVIDENCE: 3

How Does Open Access Publication Impact Readership and Citation Rates of Lumbar Spine Literature?

STUDY DESIGN

This was a retrospective review.

OBJECTIVE

The objective of this study was to assess the impact of open access (OA) publication on citation rates and attention scores of literature related to lumbar spine surgery.

SUMMARY OF BACKGROUND DATA

OA literature allows readers to view full-text manuscripts of research publications free of charge, however, OA publication is often associated with substantial fees for authors.

METHODS

The Altmetric database was searched for articles related to lumbar spine surgery. Title, journal, publication date, Dimensions Citations, Mendeley Readers, Altmetric Attention Score (AAS), number of public mentions, and OA status were collected for each included article. The influence of OA status on Dimensions Citations, Mendeley Readers, and each individual component of the AAS was assessed. To control for journal influence, impact of OA on Dimensions Citations and AAS was separately assessed for each of the top 10 journals contributing the most mentioned articles. The top 25 most cited articles and top 25 articles by AAS were also characterized.

RESULTS

A total of 5245 articles were included, of which 2063 were published with OA and 3182 were not. OA status was a significant, independent predictor of AAS and Mendeley Readers (both P <0.001), but not Dimensions Citations ( P =0.422). OA status significantly predicted mentions in news stories ( P =0.003), Twitter posts ( P <0.001), Facebook posts ( P <0.001), and Wikipedia citations ( P =0.011). Of the top 10 contributing journals, OA status significantly predicted Dimensions Citations for European Spine Journal , Journal of Neurosurgery: Spine , and Neurosurgery ( P ≤0.005) and predicted AAS for Spine , European Spine Journal , The Spine Journal , Journal of Neurosurgery: Spine , and Neurosurgery ( P ≤0.017, all).

DISCUSSION

OA status appeared to significantly impact public attention scores, but not citation rates, although these effects did vary based on the journal in which articles were published. Authors may want to consider OA publication based on their target audience and the goal of their research.

Impact of Body Mass Index on Postsurgical Outcomes for Workers' Compensation Patients Undergoing Minimally Invasive Transforaminal Lumbar Interbody Fusion

BACKGROUND

Increased morbidity associated with obesity imposes a greater financial burden on companies that provide insurance to their employees. Few studies have investigated the relationship between body mass index (BMI) and patient-reported outcome measures (PROMs) for minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) in the workers' compensation (WC) population.

METHODS

WC patients who underwent a primary, single-level MIS TLIF were included/grouped according to BMI: nonobese (<30 kg/m2); obese I (≥30, <35 kg/m2); severe + morbid (≥35). PROMs were collected pre- and postoperatively: visual analog scale (VAS), Oswestry Disability Index (ODI), 12-Item Short Form (SF-12) physical composite score (PCS), and Patient-Reported Outcome Measurement Information System physical function (PROMIS-PF). BMI predictive power grouping on PROMs was evaluated using simple linear regression. Established minimum clinically important difference values were used to compute achievement rates across PROMs using logistic regression.

RESULTS

A total of 116 nonobese, 70 obese I, and 61 severe + morbid patients were included. Demographics among BMI grouping significantly differed in gender, hypertensive status, and American Society of Anesthesiologists score (P ≤ 0.037, all). Operative time was significantly different in perioperative values among BMI grouping (P ≤ 0.001). Increased BMI was significantly associated with greater VAS back at 12 weeks and 2 years (P ≤ 0.026, all), greater ODI preoperatively at 12 weeks and 6 months (P ≤ 0.015, all), and decreased PROMIS-PF at 12 weeks (P ≤ 0.011, all). Mean PROMs between obese I and severe + morbid cohorts differed in SF-12 PCS at 12 weeks, only (P = 0.050). ODI overall was the only parameter for which minimum clinically important difference was achieved among BMI cohorts (P ≤ 0.023).

CONCLUSION

WC patients with increased BMI were more likely to develop significant back pain and disability at numerous postoperative timepoints compared with nonobese individuals. Our findings highlight the weight management importance within WC population to minimize back pain and disability following MIS TLIF, but provide a sense of reassurance with comparable clinical improvement regardless of BMI.

CLINICAL RELEVANCE

When considering the effect of weight, surgeons may incorporate these findings in managing patient expectations in the WC population undergoing lumbar spine surgery.

LEVEL OF EVIDENCE: 3

Meeting Patient Expectations and Achieving a Minimal Clinically Important Difference for Back Disability, Back Pain, and Leg Pain May Provide Predictive Utility for Achieving Patient Satisfaction Among Lumbar Decompression Patients

OBJECTIVE

Our study evaluates minimum clinically important difference (MCID) achievement for back pain/leg pain/disability and meeting preoperative expectations as predictors of patient satisfaction after minimally invasive lumbar decompression (MIS-LD) surgery.

METHODS

Single/multilevel MIS-LD procedures were identified. Patient-reported outcome measures (preoperative/postoperative), expectations (preoperative), and satisfaction (postoperative) were collected for visual analog scale (VAS) back/VAS leg/Oswestry Disability Index (ODI). Student's t-test assessed patient-reported outcome measure improvement from preoperative baseline. Correlations between outcome and satisfaction scores were evaluated using the Pearson correlation coefficient and categorized according to strength of relationship. MCID achievement and meeting expectations were evaluated as predictors of postoperative patient satisfaction with simple linear regression. Comparison of meeting expectations or achieving MCID as predictors of satisfaction scores was performed using a post hoc Suest test comparison of standardized β-coefficients.

RESULTS

A total of 329 patients were included. All outcomes improved from baselines (P < 0.001, all) at all postoperative time points and demonstrated strong and negative correlations with satisfaction scores (P < 0.001, all). Majority of patients had their expectations met for ODI/VAS back/VAS leg and achieved MCID for ODI/VAS back/VAS leg at all time points and overall. Both MCID achievement and meeting preoperative expectations demonstrated significant associations with satisfaction scores at all time points for ODI/VAS back/VAS leg. Post hoc analysis of predictors of patient satisfaction in pain and disability demonstrated that MCID achievement was an equivalent predictor to meeting patient preoperative expectations at all postoperative time points.

CONCLUSION

Pain/disability improved after MIS-LD; improvement was strongly correlated with postoperative satisfaction. Meeting expectations/MCID achievement is associated with satisfaction. MCID achievement was equivalent to meeting expectations in predicting satisfaction at all postoperative time points for pain/disability.

Presenting Mental Health Influences Postoperative Clinical Trajectory and Long-Term Patient Satisfaction After Lumbar Decompression

OBJECTIVE

To compare patient-reported outcomes (PROMs), postoperative patient-reported satisfaction, and minimum clinically important difference (MCID) achievement after minimally invasive surgery lumbar decompression (MIS-LD) in patients stratified by their preoperative 12-Item Short-Form Mental Component Score (SF-12 MCS).

METHODS

Patients who underwent single-level/multilevel MIS-LD were included. PROMs were administered preoperatively and 6 weeks/12 weeks/6 months/1 year postoperatively. Patients were grouped by preoperative SF-12 MCS. Demographic/perioperative characteristics were compared among groups using a χ² and Student t test for categorical and continuous variables, respectively. Mean PROM and postoperative satisfaction scores were compared using an unpaired Student t test. PROM improvement within cohorts was assessed with paired-samples t test. MCID achievement rates were compared using χ² analysis.

RESULTS

A total of 297 patients were included: 111 patients in SF-12 MCS <48.9 and 186 patients in the SF-12 MCS ≥48.9 cohort. Cohorts showed mean postoperative differences for visual analog scale (VAS) back score at 12 weeks, VAS leg score at 6 weeks/12 weeks, Oswestry Disability Index (ODI) at 6 weeks/12 weeks, SF-12 MCS at all postoperative time points, and 12-Item Short-Form Physical Component Score at 6 weeks/12 weeks (P < 0.022, all). Of patients in the SF-12 MCS <48.9 cohort, more achieved MCID for SF-12 MCS at all postoperative time points and ODI at 1 year (P < 0.023, all). More patients in the SF-12 MCS ≥48.9 cohort achieved MCID for VAS leg score at 12 weeks and 12-Item Short-Form Physical Component Score at 6 weeks (P < 0.038). Patients in the SF-12 MCS <48.9 cohort showed inferior postoperative satisfaction for VAS leg score at 6 weeks/12 weeks/1 year, VAS back score at 12 weeks, and ODI at all postoperative time points.

CONCLUSIONS

Patients with inferior mental health preoperatively showed worse mean short-term postoperative clinical outcome for leg/back pain, physical function and disability, short-term and long-term postoperative satisfaction for leg pain and disability, and long-term satisfaction for sleeping/lifting/walking/standing/sex/travel.

Patient Satisfaction Following Lumbar Decompression: What is the Role of Mental Health?

OBJECTIVE

To determine the association between patient-reported depressive symptoms and patient satisfaction following minimally invasive lumbar decompression (MIS LD) METHODS: Primary, single/multilevel MIS LD were identified. Patient-reported outcome measures (PROMs) collected pre-/post-operatively included VAS back/leg, ODI, PHQ-9, and SF-12 MCS. Patients rated current satisfaction level (0-10) with back/leg pain and disability. Paired Student's t-test compared each postoperative PROM score to its preoperative baseline. At each timepoint, patients were categorized by PHQ-9 and SF-12 MCS scores. One-way ANOVA compared patient satisfaction with back/leg pain and disability among PHQ-9 subgroups. Student's t-test for independent samples compared patient satisfaction between SF-12 MCS subgroups. ANCOVA assessed differences in satisfaction between depression subgroups while controlling for pre-/post-operative values in corresponding PROMs.

RESULTS

193 patients were included. All PROMs demonstrated significant postoperative improvement from 6-weeks through 2-years(p<0.001,all) except PHQ-9 2-years(p=0.874). Mean satisfaction scores ranged from 6.9-7.9(back pain), 7.3-8.0(leg pain), and 7.6-8.0(disability). Satisfaction with back/leg pain and disability significantly differed among PHQ-9 subgroups at all postoperative timepoints(p<0.001,all). Accounting for baseline and current pain/disability values, ANCOVA revealed differences between PHQ-9 subgroups only in satisfaction with back pain 2-years(p<0.001), leg pain 12-weeks/1-year/2-years(p≤0.047,all), and disability 6-months/2-years(p≤0.049,both). Satisfaction differed between SF-12 MCS subgroups at all timepoints(p≤0.047), except back pain 6-months(p=0.263). Accounting for baseline and postoperative pain/disability, ANCOVA revealed differences in satisfaction between SF-12 MCS groups only for back/leg pain 2-years(p≤0.001,both).

CONCLUSION

Independent effect of depression at long-term follow-up was significant. This highlights the importance of understanding the interaction between physical and mental health outcomes to optimize patients' perceptions of surgical outcome.

Lateral Lumbar Interbody Fusion: Single Surgeon Learning Curve

OBJECTIVE

To characterize lateral lumbar interbody fusion surgical learning curve and investigate changes in perioperative and postoperative clinical parameters associated with increased operative experience.

METHODS

In a case series, surgical learning curve was defined using 3-parameter asymptotic regression and piecewise linear regression, yielding learning phase (patients 1-53) and proficient phase (patients 54-179) cohorts. Using a 5-point grading scale, ipsilateral iliopsoas (hip-flexion) and quadriceps (knee-extension) muscle strength and thigh and groin sensory disturbances were compared for differences preoperatively versus postoperatively using χ² test. Patient-reported outcome measures were collected preoperatively and postoperatively and compared between cohorts with unpaired t test.

RESULTS

The proficient phase cohort demonstrated significantly reduced operative time, estimated blood loss, postoperative length of stay, and narcotic consumption on postoperative days 0 and 1. The proficient phase cohort displayed decreased disability at 6 weeks and 6 months and demonstrated significant improvement at all time points for disability, pain, and physical function except for 6 weeks and 2 years for physical function, whereas the learning phase cohort demonstrated improvement in disability beginning at 6 months, leg pain at all time points, and back pain through 6 months. Ipsilateral groin and thigh sensory disturbances and iliopsoas and quadriceps weakness improved with increasing operative experience.

CONCLUSIONS

The proficient phase cohort demonstrated significantly improved perioperative profile, reduced complication rate, and reduced rates of iliopsoas and quadriceps weakness. While the proficient phase cohort demonstrated earlier improvement in disability and physical function scores compared with the learning phase cohort, 2-year outcome measures did not differ. Long-term clinical outcomes suggest that patient safety and quality of life are not compromised during the learning phase, but patients may be particularly susceptible to femoral nerve injury early in a surgeon's practice.

Obesity and Workers' Compensation in the Setting of Minimally Invasive Lumbar Decompression

OBJECTIVE

To investigate the influence of body mass index (BMI) on perioperative outcomes, postoperative patient-reported outcome measures (PROMs), and minimal clinically important difference (MCID) achievement among workers' compensation (WC) claimants undergoing minimally invasive lumbar decompression (MIS-LD).

METHODS

WC patients diagnosed with herniated nucleus pulposus undergoing single-level MIS-LD were identified. Patients were divided into 3 groups: Non-obese (<30 kg/m²), Obese I (≥30 and <35 kg/m²), and Obese II/III (≥35 kg/m²). PROMs were collected preoperatively and at 6 weeks, 12 weeks, 6 months, 1 year, and 2 years postoperatively. The predictive influence of BMI grouping on mean PROM scores was computed using simple linear regression. To compare PROMs between groups, post hoc pairwise comparisons of adjusted means were utilized. MCID achievement was compared between groups with χ² analysis.

RESULTS

A total of 81 patients were in the Non-obese cohort, and 43 and 45 in the Obese I and Obese II/III cohorts, respectively. Visual analog scale (VAS) leg, Oswestry Disability Index (ODI), and 12-Item Short Form Physical Composite Score (SF-12 PCS) were worse in the Obese I cohort at 12 weeks, and SF-12 PCS was lower in the Obese I vs. Obese II/III subgroup analysis (P ≤ 0.045, all). MCID achievement rates for ODI were higher for the Non-obese group at 12 weeks and overall (P ≤ 0.049, both). MCID attainment for VAS back was higher among the Non-obese cohort at 6-weeks (P = 0.022).

CONCLUSIONS

Patients with higher levels of obesity were more likely to experience longer length of stay and delayed discharge following MIS-LD. Increasing BMI was generally not a significant predictor of postoperative pain, disability, or physical health PROMs at most timepoints. MCID achievement rates for disability relief were significantly higher for non-obese patients.

The Worldwide Influence of Social Media on Cervical Spine Literature

BACKGROUND

The Altmetric (Digital Science, Holtzbrinck Publishing) Attention Score (AAS) is an automatically calculated score that accounts for other literary influences, which include academic sources as well as nonacademically focused social media outlets such as Twitter, Facebook, and news articles. This study compares the most popular cervical surgery articles on social media to the most cited articles within peer-reviewed literature and identifies journals that contribute the most articles and geographic trends.

METHODS

We searched the Altmetric database for cervical spine surgery articles since inception using the search phrase "cervical" and "spine." We ranked journals that contributed the most articles and calculated their AAS, contributing social media outlets (eg, Twitter, Facebook, News, etc) and citation counts. We also ranked the top 100 most popular cervical spine articles on social media and compared them to the most cited articles. Countries were assessed based on their mentions through the most contributing social media platform.

RESULTS

Of the 527 total journals identified in our search, the top 10 journals were responsible for contributing 60.2% of the total articles. The 3 journals that contributed the most articles were Spine (18.9%), European Spine Journal (11.8%), and The Spine Journal (10.3%). The journals with the highest AAS scores included Journal of Neurosurgery: Spine (11.3), Spine (8.8), and Journal of Manipulative & Physiological Therapeutics (5.8). Social media outlets that contributed the most mentions per article were Twitter (4.4), Facebook (0.5), and news sources (0.3). Among all countries contributing Twitter mentions, the 3 countries with the most cervical spine posts included the United States (23.3%), the United Kingdom (10.3%), and Spain (5.5%).

CONCLUSION

Our evaluation of cervical spine literature revealed Twitter, Facebook, and news sources are the most common social media outlets influencing title dissemination. Journals contributing the most articles did not necessarily have the highest average AAS.

CLINICAL RELEVANCE

Spinal surgeons should consider utilization of social media outlets, such as Twitter, Facebook, and news sources, to potentially increase the dissemination of their articles.

LEVEL OF EVIDENCE: 3

Consequences of Progressive Full-Thickness Focal Chondral Defects Involving the Medial and Lateral Femoral Condyles After Meniscectomy: A Biomechanical Study Using a Goat Model

Background:

Full-thickness chondral defects alter tibiofemoral joint homeostasis and, if left untreated, have the potential to progress to osteoarthritis.

Purpose:

To assess the effects of isolated and dual full-thickness chondral defect size and location on the biomechanical properties of the lateral femoral condyle (LFC) and medial femoral condyle (MFC) during dynamic knee flexion in goat knees without menisci.

Methods:

In 12 goat knees, we created progressively increasing full-thickness circular chondral defects (3-, 5-, and 7.5-mm diameter) in the weightbearing contact area of flexion and extension in the MFC, the LFC, or both. Each knee was fixed into a custom steel frame and attached to a motor with sensors inserted intra-articularly. For each testing condition, the knee was loaded to 100 N and underwent a dynamic range of motion between 90° of flexion and 30° of extension. The following parameters were collected: contact area, contact pressure, contact force, peak area, and peak pressure.

Study Design:

Controlled laboratory study.

Results:

The peak pressure at the defect rim of the MFC at full extension increased by 51.51% from no defect (1.887 MPa) to a 7.5-mm defect (2.859 MPa) (P < .001), and the peak pressure at the defect rim of the LFC at full extension increased by 139.14% from no defect (1.704 MPa) to a 7.5-mm defect (4.075 MPa) (P < .001). The peak pressures for LFC defects at all 3 diameters were significantly greater when compared with dual defects consisting of increasing LFC defect diameter and constant MFC defect diameter (P < .001 for all).

Conclusion:

Extremely large increases in peak pressure were seen at the rim of articular cartilage defects when evaluated under dynamic loading conditions. Isolated LFC defects experienced a greater increase in defect rim stress concentrations when compared with isolated MFC defects for equivalent increases in defect size. Defect size played a significant role independent of location for peak pressures on the MFC and LFC.

Clinical Relevance:

Significant rim-loading effects increase with defect size under dynamic loading and may result in increasingly rapid progression of articular cartilage lesions. Within the context of this goat model, findings suggest that lateral compartment chondral lesions are more likely to progress than medial compartment lesions of equivalent size.

Systematic Review: Applications of Intraoperative Ultrasound in Spinal Surgery

BACKGROUND

Due to increased practicality and decreased costs and radiation, interest has risen for intraoperative ultrasound (iUS) in spinal surgery applications; however, few studies have provided a robust overview of its use in spinal surgery. We synthesize findings of existing literature on usage of iUS in navigation, pedicle screw placement, and identification of anatomy during spinal interventions.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were utilized in this systematic review. Studies were identified through PubMed, Scopus, and Google Scholar databases using the search string. Abstracts mentioning iUS in spine applications were included. Upon full-text review, exclusion criteria were implemented, including outdated studies or those with weak topic relevance or statistical power. Upon elimination of duplicates, multi-reviewer screening for eligibility, and citation search, 44 manuscripts were analyzed.

RESULTS

Navigation using iUS is safe, effective, and economical. iUS registration accuracy and success is within clinically acceptable limits for image-guided navigation (Table 2). Pedicle screw instrumentation with iUS is precise with a favorable safety profile (Table 2). Anatomical landmarks are reliably identified with iUS, and surgeons are overwhelmingly successful in neural or vascular tissue identification with iUS modalities including standard B mode, doppler, and contrast-enhanced ultrasound (CE-US) (Table 3). iUS use in traumatic reduction of fractures properly identifies anatomical structures, intervertebral disc space, and vasculature (Table 3).

CONCLUSION

iUS eliminates radiation, decreases costs, and provides sufficient accuracy and reliability in identification of anatomical and neurovascular structures in various spinal surgery settings.

Workers' Compensation Association With Clinical Outcomes After Anterior Cervical Diskectomy and Fusion

BACKGROUND

Research has suggested that workers' compensation (WC) status can result in poor outcomes after anterior cervical diskectomy and fusion (ACDF).

OBJECTIVE

To determine the influence WC status has on postoperative clinical outcomes after ACDF.

METHODS

A surgical database was reviewed for patients undergoing primary or revision single-level ACDF. Patients were grouped into WC vs Non-WC, and differences in baseline characteristics were assessed. Postoperative improvement was assessed for differences in mean scores between WC subgroups for visual analog scale (VAS) arm, VAS neck, 12-item Short Form Physical Composite Score, Patient-Reported Outcomes Measurement Information System physical function (PF), and Neck Disability Index (NDI) at preoperative and postoperative time points. Minimum clinically important difference (MCID) achievement was compared between groups.

RESULTS

The patient cohort included 44 with WC and 95 without. The cohort was 40% female with an average age of 48 years and mean body mass index of 30. Mean VAS arm, VAS neck, NDI, 12-item Short-Form Physical Composite Score, and Patient-Reported Outcomes Measurement Information System PF scores differed between groups; however, the difference was not sustained at the 1-yr time point. MCID achievement among WC subgroups was different for VAS arm (6 wk through 6 mo, P = .005), VAS neck (3 and 6 mo, P < .01), and NDI (3 and 6 mo, P < .05). No statistically significant difference was noted between cohorts for overall rates of MCID achievement for all patient-reported outcome measures collected.

CONCLUSION

WC patients reported similar preoperative and 1-yr postoperative neck and arm pain compared with non-WC patients after ACDF. One-yr MCID achievement rates were similar between cohorts for disability and PF scores.

Does an Author's Social Media Presence Affect Dissemination of Spine Literature?

OBJECTIVE

Our study assesses the impact of an author's social media presence on citation rates and readership of spine literature.

METHODS

Altmetric database was queried for spine-related articles between 2016-2021; top 100 by Altmetric Attention Score(AAS) were assessed. Public profile presence, number of followers, number of posts, and promotion of articles were assessed for Twitter/Instagram. Social media profiles were identified by searching for the author's name followed by "Twitter" or "Instagram" on Google.com or searching each platform. Descriptive statistics assessed social media use and attention metrics. Negative binomial regression assessed presence/promotion/number of followers/number of posts on Twitter/Instagram as predictors of Dimensions citation rates/AAS/Mendeley reader counts, while accounting for time passed since publication.

RESULTS

Twitter promotion was noted for 9.0% of articles and Instagram promotion for 1.0%. Mean numbers of Twitter and Instagram followers were 447.9±1406.1(range 0-9079) and 173.2±1097.1(range 0-10700). Mean numbers of Twitter and Instagram posts were 411.6±1210.5 and 18.4±96.4, respectively. Dimensions citations ranged from 0-641, AAS from 79-2257, and Mendeley readers from 2-1854. Following negative binomial regression, Instagram presence was identified as a significant predictor of Mendeley readers(p=0.043), number of Twitter posts was a significant predictor of AAS(p=0.008). Additionally, Twitter presence was identified as a negative predictor of Mendeley Readers(p=0.005) and Twitter promotion was identified as a negative predictor of AAS (p=0.003).

CONCLUSION

Activity on Twitter and Instagram may have variable associations with altmetrics of literature visibility and readership but with citation rates. Interestingly, presence/promotion on Twitter predicted less attention/readership, while Instagram presence predicted higher Mendeley readership.

Preoperative Duration of Symptoms Does Not Affect Outcomes of Anterior Lumbar Interbody Fusion

BACKGROUND

Previous studies have examined the impact of preoperative duration of symptoms (DOS) on lumbar spinal surgery outcomes although this has not been explored for anterior lumbar interbody fusion (ALIF).

OBJECTIVE

To assess the impact of preoperative DOS on patient-reported outcome measures (PROMs) of ALIF with posterior instrumentation.

METHODS

A database was retrospectively reviewed for ALIFs with posterior instrumentation. PROMs recorded at preoperative, 6-wk, 12-wk, 6-mo, and 1-yr postoperative timepoints included Visual Analog Scale back and leg, Oswestry Disability Index, 12-Item Short-Form Physical Component Score (SF-12 PCS), and PROM Information System physical function. Achievement of minimum clinically important difference (MCID) was determined by comparing differences in postoperative PROMs from baseline to established values. Patients were grouped based on preoperative DOS into <1-yr and ≥1-yr groups. Differences in PROMs were compared using a t-test, whereas MCID achievement used a χ2 test.

RESULTS

Fifty-three patients were included, with 20 in the <1-yr group and 33 in the ≥1-yr group. The most common diagnosis was isthmic spondylolisthesis. No significant preoperative differences were observed in any PROM. DOS groups demonstrated significantly different scores for SF-12 PCS at 6 wk (P = .049). No significant differences in MCID achievement were observed between groups for any PROM.

CONCLUSION

ALIF patients demonstrated similar levels of pain, disability, and physical function regardless of preoperative DOS, except for back pain and physical function at intermittent timepoints. MCID achievement did not differ based on DOS for all outcome measures.

Change in Patient-Reported Outcome Measures as Predictors of Revision Lumbar Decompression Procedures

Objective

To assess change in Patient-Reported Outcome Measures (PROM) as predictors for revision lumbar decompression (LD).

Methods

Patients who underwent primary, single or multilevel LD were retrospectively reviewed. Patients were categorized according to whether or not they underwent revision LD within 2 years of the primary procedure. Visual analogue scale (VAS), Oswestry Disability Index (ODI), 12-item Short Form Health Survey and 12-item Veterans RAND physical component score (SF-12 PCS and VR-12 PCS), and Patient-Reported Outcome Measurement Information System physical function (PROMIS-PF) were recorded. Delta PROM scores were evaluated for differences between groups and as a risk factor for a revision LD.

Results

The study included 135 patients, 91 undergoing a primary procedure only and 44 undergoing a primary and revision procedure. Matched patients did not demonstrate any significant differences in demographics or perioperative characteristics. Patients who underwent a revision had a mean time to revision of 7.4 ± 5.7 months. Primary cohort significantly improved for all PROMs (all p < 0.05), while the primary plus revision cohort significantly improved for VAS back, ODI, and PROMIS-PF (all p < 0.05). However, cohorts differed in VAS back and PROMIS-PF (p < 0.05). Delta PROMs were not a significant risk factor for revision except at 6 months for PROMIS-PF (p = 0.024).

Conclusion

LD has been associated with reliable outcomes, but early identification of patients at risk for revision is critical. This study suggests that tools such as PROMIS-PF may serve a role in predicting who is at risk and the 6-month follow-up period may be valuable for counseling patients who are not experiencing improvement.

Influence of Predominant Neck vs Arm Pain on ACDF Outcomes: A Follow-Up Study

OBJECTIVE

To assess differences in postoperative PROMs and MCID attainment following single-level ACDF based on predominant preoperative pain symptom.

METHODS

Primary, single-level ACDFs were identified. PROMs included VAS arm and neck/SF-12 PCS/PROMIS-PF/NDI, collected preoperatively and at 6-week/12-week/6-month/1-year/2-year postoperative timepoints. Patients were grouped: pAP (preoperative VAS arm > preoperative VAS neck) vs pNP (preoperative VAS neck > preoperative VAS arm). Chi-square and Student's t-test compared demographic and perioperative characteristics. Student's t-test evaluated change from preoperative to postoperative PROM values, and compared PROMs between groups. MCID achievement was determined using established threshold values. MCID attainment rates were compared using chi-squared.

RESULTS

110 patients were assessed-52 pNP/58 pAP. Demographics did not differ between cohorts. Total 1-year arthrodesis rate was 95.7% and did not differ by grouping. pNP patients improved significantly from preoperative to postoperative at 12-weeks-1-year for PROMIS-PF, 6-months/1-year for SF-12 PCS, 6-weeks-1-year for VAS neck, 6-weeks-6-months for VAS arm, and 6-weeks through 2-years for NDI(p≤0.035, all). pAP patients improved significantly from preoperative to all postoperative timepoints for PROMIS-PF, 6-months-2-years for SF-12 PCS, 6-weeks-1-year for VAS neck, 6-weeks-1-year for VAS arm, and 6-weeks-6-months for NDI(p≤0.040, all). Mean PROMIS-PF was higher for pAP at 6-weeks, preoperative VAS neck lower for pAP, and preoperative VAS arm higher for pAP(p≤0.013, all). MCID attainment was significantly higher among pAP only for PROMIS-PF from 6-weeks-6-months, SF-12 PCS 6-weeks, and VAS arm 12-weeks.

CONCLUSION

Predominant pain symptom demonstrated little effect on perioperative characteristics and postoperative PROMs. ACDF candidates will likely experience similar clinically meaningful postoperative improvements in physical function/disability/pain.

Baseline Risk Factors for Prolonged Opioid Use Following Spine Surgery: Systematic Review and Meta-Analysis

OBJECTIVE

To conduct a comprehensive systematic review and meta-analysis of current retrospective cohort studies to identify significant preoperative risk factors for prolonged postoperative opioid use following spine surgery.

METHODS

Studies were identified according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) through a search of the PubMed, Google Scholar, Scopus, Cochrane databases. Unique articles were screened by two independent reviewers. Primary research articles reporting odds ratios (OR) of risk factors for prolonged opioid use as following spine surgery were included. Prolonged opioid use was defined as continued use ≥ 3 months following surgery, and study quality was evaluated using the Newcastle-Ottawa Scale (NOS). Random effects meta-analysis was performed to calculate pooled OR and confidence intervals.

RESULTS

648 studies were returned upon initial search. Following duplicate removal, 492 titles and abstracts were screened. After full-text review of 68 studies, 19 final studies including 168,961 patients were eligible for meta-analysis. NOS scores ranged from 6-9. Seventeen risk factors for long-term opioid use were assessed by meta-analysis. Preoperative opioid use, depression, depression and/or anxiety, drug abuse or dependency, female gender, fibromyalgia, lower back pain, tobacco use, and chronic pulmonary disease were found to be statistically significant risk factors for prolonged opioid use.

CONCLUSION

These results suggest that several patient-level factors may play a role in the tendency to persistently utilize opioids following spine surgery. By preoperatively identifying these characteristics, clinicians may be better able to identify patients that are at-risk and employ methods to mitigate potential long-term opioid use.

The Effect of the Severity of Preoperative Disability on Patient-Reported Outcomes and Patient Satisfaction Following Minimally Invasive Transforaminal Lumbar Interbody Fusion

OBJECTIVE

To compare patient-reported outcomes (PROMs), satisfaction, and minimum clinically important difference (MCID) achievement following minimally invasive transforaminal lumbar interbody fusion stratified by preoperative disability.

METHODS

Minimally invasive transforaminal lumbar interbody fusions were grouped by preoperative Oswestry Disability Index (ODI) score: ODI <41 or ODI ≥41. PROMs administered pre/postoperatively included Patient-Reported Outcomes Measurement Information System physical function (PROMIS-PF), visual analog scale (VAS) back/leg, ODI, and 12-Item Short-Form Physical Composite Score (SF-12 PCS)/12-Item Short-Form Mental Composite Score (SF-12 MCS). Satisfaction scores were collected for VAS back/leg and ODI. Coarsened exact match controlled for differences between cohorts. T tests compared mean PROMs and postoperative improvement/satisfaction between cohorts. Simple logistic regression compared MCID achievement.

RESULTS

After coarsened exact matching, there were 118 patients in the ODI ≤41 and 377 patients in the ODI >41 cohort. The ODI >41 cohort saw greater postoperative inpatient VAS pain score and narcotic consumption on days 0/1 (P < 0.018, all). PROMs differed between cohorts: PROMIS-PF, SF-12 PCS, ODI, VAS back/leg at all postoperative time points and SF-12 MCS at 6 weeks/12 weeks/6 months/1 year (P < 0.045, all). Patients in the ODI >41 cohort demonstrated greater proportion achieving MCID for ODI at all postoperative time points and for SF-12 MCS 6-week/12-week/6-month/1-year (P < 0.040, all). The ODI ≤41 cohort demonstrated greater MCID achievement for overall PROMIS-PF and SF-12 PCS 6 months (P < 0.047, all). Postoperative satisfaction was greater in the ODI ≤41 cohort for VAS leg 6 weeks/12 weeks, VAS back 6 weeks/12 weeks, and ODI all postoperative time points (P < 0.048, all).

CONCLUSIONS

Preoperative disability associated with worse postoperative PROMs and patient satisfaction for disability, back/leg pain at multiple time points. MCID achievement rates across cohorts were similar for most PROMs at most postoperative time points. Patients with severe disability may have unrealistic expectations for surgical benefits, influencing corresponding postoperative satisfaction.

How Do Patient-Reported Outcomes Vary Between Lumbar Fusion Patients with Complete Versus Incomplete Follow-Up?

OBJECTIVE

We sought to assess differences in patient-reported outcome measures (PROMs) between patients who do and do not follow up for 2 years after lumbar fusion.

METHODS

Primary, elective, single-level anterior lumbar interbody fusion, lateral lumbar interbody fusion, or transforaminal lumbar interbody fusion procedures were identified. Patients were grouped by 2-year PROM follow-up completion. Mean and delta PROM scores for visual analog scale (VAS) back and leg, Oswestry Disability Index (ODI), short-form (SF)-12 Physical Composite Score (PCS), and Mental Composite Score (MCS) were computed for both groups preoperatively and postoperatively. Minimum clinically important difference (MCID) achievement was determined for PROM scores using established threshold values. Linear and logistic regression assessed mean and ΔPROM scores as predictors of 2-year follow-up completion and compared MCID achievement between groups, respectively.

RESULTS

We included 316 lumbar fusion patients. PROM scores were more favorable for complete follow-up patients for 6-month VAS back (P = 0.003), 6-month and 1-year ODI (P ≤ 0.027, both), and 6-week and 6-month SF-12 PCS (P ≤ 0.015, both). Six-month VAS back (P = 0.007); 6-month and 1-year ODI (P ≤ 0.028, both); 6-week, 6-month, and 1-year SF-12 PCS (P ≤ 0.041, all); and 6-week SF-12 MCS (P ≤ 0.028, both) significantly predicted 2-year follow-up. ΔPROMs significantly differed between groups at 1 year for ΔVAS leg (P = 0.029), ΔODI (P = 0.013), and ΔSF-12 MCS (P = 0.004). One-year ΔVAS leg (P = 0.035), ΔODI (P = 0.011), and ΔSF-12 MCS (P = 0.003) significantly predicted follow-up. MCID achievement for ΔPROMs significantly differed between groups for 6-week VAS leg (P = 0.035), overall ODI (P = 0.034), and SF-12 PCS from 12 weeks through 1 year (P ≤ 0.011, all) and overall (P < 0.001).

CONCLUSIONS

Patients with full follow-up demonstrated significantly more favorable outcome scores and improvement in pain, disability, and physical function at several postoperative time points.

Single-Level Minimally Invasive Transforaminal Lumbar Interbody Fusion versus Anterior Lumbar Interbody Fusion with Posterior Instrumentation at L5/S1

OBJECTIVE

To compare outcomes between minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and anterior lumbar interbody fusion (ALIF) at L5/S1.

METHODS

Primary, elective, single, MIS-TLIF, or ALIF with posterior fixation at L5/S1 were identified. Patient-reported outcome measures (PROMs) were collected. Coarsened exact matching was used to control for significant differences. Achievement of minimum clinically important difference [MCID] was determined by comparing ΔPROM scores with threshold values. Demographic/perioperative characteristics were compared between MIS-TLIF and ALIF cohorts using χ² Student t tests. Differences in mean PROM scores, MCID rates, and postoperative complications were evaluated using an unpaired t test.

RESULTS

After coarsened exact matching, 93 patients received MIS-TLIF and 50 received ALIF. Cohorts differed in operative time, estimated blood loss, and postoperative narcotic consumption on postoperative day 0 (P < 0.034, all). Mean PROMs differed significantly on 12-Item Short-Form Physical Component Summary at 6 weeks and 1 year, Patient-Reported Outcomes Measurement Information System Physical Function at 6 weeks, Oswestry Disability Index at 6 weeks, and visual analog scale (VAS) back at 6 weeks, with the ALIF cohort showing significantly improved mean PROMs (P ≤ 0.044, all). Significantly greater rates were reported of MCID achievement for PROMs for the ALIF cohort: VAS back at 6 weeks, Oswestry Disability Index at 12 weeks, 12-Item Short-Form Physical Component Summary at 6 weeks, and Patient-Reported Outcomes Measurement Information System Physical Function at 12 weeks (P ≤ 0.047, all). A greater rate of MCID achievement for the MIS-TLIF cohort was seen for 6-week and overall VAS leg (P < 0.046, all). Postoperative fever was greater in the TLIF cohort (9.6% vs. 2.0%; P < 0.047).

CONCLUSIONS

Patients undergoing ALIF showed significantly improved rates of MCID achievement for disability, physical function, and back pain during the early postoperative period. However, the overall MCID achievement rate for leg pain was higher for the MIS-TLIF cohort.

The Effect of the Severity of Preoperative Back Pain on Patient-Reported Outcomes, Recovery Ratios, and Patient Satisfaction Following Minimally Invasive Transforaminal Lumbar Interbody Fusion (MIS-TLIF)

BACKGROUND

Limited literature has addressed impact of preoperative back pain severity on patient-reported outcome measures (PROMs), recovery ratios (RRs), and patient satisfaction following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

METHODS

MIS TLIFs were retrospectively identified and grouped: preoperative visual analog scale (VAS) back ≤7 or VAS back >7. PROMs, including PROMIS-PF, VAS back and leg, Oswestry Disability Index (ODI), and SF-12 Physical Composite Score and Mental Composite Score (MCS), were collected pre- and postoperatively. A PROM's RR was calculated as proportion of postoperative improvement to overall potential improvement.

RESULTS

In total, 740 patients were included: 359 patients with VAS back ≤7 and 381 patients with VAS back >7. The VAS back >7 cohort reported significantly greater postoperative inpatient pain (P ≤ .003, both). All preoperative and the following postoperative PROMs favored the VAS back ≤7 cohort: PROMIS-PF 2-years, VAS back overall, SF-12 Physical Composite Score 12 weeks and 1 year, SF-12 MCS 6 weeks/12 weeks, VAS leg 6 weeks, 12 weeks, 6 months, and 2 years, and ODI overall (P ≤ 0.048, all). The VAS back >7 cohort demonstrated greater delta PROMs for all VAS back and ODI except 2 years (P ≤ 0.021, all). A greater proportion of patients in the VAS back >7 group achieved minimal clinically important difference for VAS back overall, ODI 6 weeks/12 weeks, PROMIS-PF 6 weeks, and SF-12 MCS 6 weeks/6 months (P ≤ 0.044, all). The VAS back>7 cohort RR was significantly greater for VAS back 6 months and VAS leg 6 months/2 years (P ≤ 0.034, all). The VAS back ≤7 cohort's postoperative satisfaction was significantly greater for VAS back 12 weeks, VAS leg 12 weeks, and ODI 6 weeks/12 weeks (P ≤ 0.046, all).

CONCLUSIONS

Patients with greater preoperative back pain demonstrated significantly worse postoperative scores for most PROMs at most time points and significantly worse patient satisfaction for disability, back and leg pain at multiple time points.

Validation of VR-12 Physical Function in Minimally Invasive Lumbar Discectomy

BACKGROUND

Although the Veterans RAND 12-item Physical Component Survey (VR-12 PCS) has been broadly used to evaluate patient-reported outcome measures (PROMs) in spine surgery, its feasibility for use in patients undergoing minimally invasive lumbar discectomy (MIS LD) has not been well studied. This study aimed to assess the feasibility of VR-12 PCS for use up to 2 years postoperatively for MIS LD by correlation with PROMs for physical function.

METHODS

Patients undergoing primary single-level MIS LD procedures were reviewed retrospectively. Results on the VR-12 PCS, 12-Item Short Form (SF-12) PCS, and Patient-Reported Outcomes Measurement Information System (PROMIS PF) were recorded preoperatively and up to 2 years postoperatively. Improvements in postoperative PROMs were calculated and assessed for significant differences from baseline values. Correlation significance and strength were evaluated between VR-12 PCS and SF-12 PCS or PROMIS PF. Scatterplots were constructed to demonstrate relationships of VR-12 PCS with SF-12 PCS and PROMIS PF at each time point.

RESULTS

Our cohort comprised 402 patients. Patients improved significantly from preoperative baseline for all 3 PROMs at all postoperative time points. Both Pearson's correlation and time-independent partial correlation revealed statistically significant strong correlations of VR-12 PCS with SF-12 PCS and PROMIS PF through 2-years.

DISCUSSION

Physical function scores for VR-12, SF-12, and PROMIS PF all demonstrated significant improvements following MIS LD. Strongly statistically significant correlations of VR-12 PCS with SF-12 PCS and PROMIS PF from preoperative measures through 2 years demonstrate the feasibility of VR-12 for assessing patient-reported physical function in MIS LD patients.

Multimodal Analgesic Management for Lumbar Decompression Surgery in the Ambulatory Setting: Clinical Case Series and Review of the Literature

BACKGROUND

Effective pain control is vital for successful surgery in the ambulatory setting. Our study aims to characterize a case series of patients who underwent lumbar decompression (LD) in the ambulatory surgical center (ASC) with the use of a multimodal analgesic (MMA) protocol.

METHODS

A prospective surgical registry was retrospectively assessed for patients who underwent single or multilevel LD in an ASC using MMA from 2013 to 2019. Observation in excess of 23 hours was not permitted at the ASC, and patients were required to be discharged the same day. Length of stay, patient-reported visual analog scale pain scores before discharge, and the quantity of narcotic medications administered to patients before discharge were recorded. Quantity of narcotic medications were converted into units of oral morphine equivalents and summed across all types of narcotic medications prescribed.

RESULTS

A total of 499 patients were included. In total, 86.0% (429) of the patients underwent a single-level decompression procedure, 13.8% (69) of patients underwent a 2-level, and 0.2% (1) of the patients underwent a 3-level procedure; 83.6% (417) of the patients in this study underwent a primary LD, and 14.0% (70) underwent a revision decompression.

CONCLUSIONS

This is the largest clinical case series focused on LD procedures within an ASC requiring no planned 23-hour observation. This study demonstrates the feasibility of performing LD surgery in an ASC with proper patient selection, surgical technique, and MMA protocol. All patients were discharged from the surgical center on the same day of surgery.

Diabetes Mellitus Does Not Impact Achievement of a Minimum Clinically Important Difference Following Anterior Cervical Discectomy and Fusion

BACKGROUND

Diabetes mellitus (DM) has been identified as a risk factor for poorer outcomes following anterior cervical discectomy and fusion (ACDF). This study aims to evaluate the impact DM has on achievement of MCID (minimum clinically important difference) following ACDF.

METHODS

A surgical database was reviewed for patients who underwent primary, single-level ACDF procedures with posterior instrumentation. Visual analog scales (VAS) Arm and Neck, Neck Disability Index (NDI), and Patient-Reported Outcomes Measurement Information System (PROMIS) and 12-item Short Form (SF-12) scores for physical function (PF) were recorded. MCID achievement was calculated using pre-established values from the literature. Intergroup differences in demographic, perioperative characteristics, mean outcome scores and rates of MCID achievement were calculated.

RESULTS

There were 43 patients with diabetes and 320 patients without diabetes. DM status was significantly associated with age, ethnicity, hypertension, American Society of Anesthesiologists physical classification score, Charlson Comorbidity Index, and insurance type (all P ≤ 0.041). Postoperative length of stay was significantly greater for the DM group (P = 0.011). Mean VAS Arm and NDI differed at 6 months (P ≤ 0.049, both) and PROMIS-PF differed from 6 weeks through 6 months (P ≤ 0.039, all). Patients without diabetes significantly improved in all PROMs by 1 year postoperatively (P < 0.01, all). Patients with diabetes significantly improved in VAS Neck and Arm, SF-12 physical component score, and PROMIS-PF by 1 year (all P ≤ 0.013) but NDI significantly improved only at 12 weeks (P = 0.038). Intergroup differences for MCID achievement were demonstrated at 6 months for NDI and SF-12 physical component score (P ≤ 0.008).

CONCLUSIONS

Although moderate intergroup differences in MCID achievement were demonstrated, the results of this study suggest that patients may realize similar benefits of ACDF surgery regardless of DM status.

Human metapneumovirus, Australia, 2001-2004

We examined 10,025 respiratory samples collected for 4 years (2001-2004) and found a 7.1% average annual incidence of human metapneumovirus. The epidemic peak of infection was late winter to spring, and genotyping showed a change in predominant viral genotype in 3 of the 4 years.

Human metapneumovirus, Australia, 2001-2004

We examined 10,025 respiratory samples collected for 4 years (2001-2004) and found a 7.1% average annual incidence of human metapneumovirus. The epidemic peak of infection was late winter to spring, and genotyping showed a change in predominant viral genotype in 3 of the 4 years.

Genetic diversity of human metapneumovirus over 4 consecutive years in Australia

The molecular epidemiologic profile of human metapneumovirus (hMPV) infection has likely been skewed toward certain genetic subtypes because of assay-design issues, and no comprehensive studies have been conducted to date. Here, reverse-transcription polymerase chain reaction was used to screen 10,319 specimens from patients presenting to hospitals with suspected respiratory tract infections during 2001-2004. After analysis of 727 Australian hMPV strains, 640 were assigned to 1 of 4 previously described subtypes. hMPV was the most common pathogen detected, and subtype B1 was the most common lineage. Concurrent, annual circulation of all 4 hMPV subtypes in our study population was common, with a single, usually different hMPV subtype predominating in each year.

Molecular assays for detection of human metapneumovirus

The recent description of the respiratory pathogen human metapneumovirus (hMPV) has highlighted a deficiency in current diagnostic techniques for viral agents associated with acute lower respiratory tract infections. We describe two novel approaches to the detection of viral RNA by use of reverse transcriptase PCR (RT-PCR). The PCR products were identified after capture onto a solid-phase medium by hybridization with a sequence-specific, biotinylated oligonucleotide probe. The assay was applied to the screening of 329 nasopharyngeal aspirates sampled from patients suffering from respiratory tract disease. These samples were negative for other common microbial causes of respiratory tract disease. We were able to detect hMPV sequences in 32 (9.7%) samples collected from Australian patients during 2001. To further reduce result turnaround times we designed a fluorogenic TaqMan oligoprobe and combined it with the existing primers for use on the LightCycler platform. The real-time RT-PCR proved to be highly reproducible and detected hMPV in an additional 6 out of 62 samples (9.6%) tested during the comparison of the two diagnostic approaches. We found the real-time RT-PCR to be the test of choice for future investigation of samples for hMPV due to its speed, reproducibility, specificity, and sensitivity.

Variations of some plasma components after closed fractures

1) Variations in the serum concentrations of total proteins and the electrophoretic fractions, glycoprotein, mucoprotein, fibrinogen, erythrocyte sedimentation rate, calcium, phosphorus, alkaline, and acid phosphatases were analyzed until the 30th day following uncomplicated fracture of shafts of long bones of the limbs in 25 cases. 2) A significant fall of albumin with concomitant rise of alpha 1, alpha 2, and beta globulins were noted until 30th day. 3) Mucoprotein, glycoprotein, and fibrinogen showed parallel elevations with that of alpha and beta globulins. 4) The peak values of alpha 1 and alpha 2 globulins, mucoprotein, and fibrinogen were registered on the 10th day after trauma. Albumin showed maximum fall on the 10th day in all these cases. 5) Glycoprotein showed a peak value on the 5th day. 6) Total protein and gamma globulin remained almost unchanged throughout the studies. 7) Beta globulin showed higher values and paralleled more closely the fibrinogen and erythrocyte sedementation rates. 8) The elevations of beta globulin, fibrinogen, and erythrocyte sedimentation rate were higher, and persisted beyond 30 days in lower-limb fractures as compared to upper-limb fractures. 9) Serum calcium, phosphorus, alkaline phosphatase, and acid phosphatase were not significantly different following fractures and therefore did not reflect much physiologic variation. 10) The most significant changes in the levels of plasma fractions studied were conspicuous on the 10th day and lasted for about 1 month.