Patient-reported outcomes in spine surgery: past, current, and future directions

Single-center pilot study of remote therapeutic monitoring in patients with operative spinal pathologies

OBJECTIVES

Spine pathology affects a significant portion of the population, leading to neck and back pain, impacting quality of life, and potentially requiring surgical intervention. Current pre- and postoperative monitoring methods rely on patient reported outcome (PRO) measures and lack continuous objective data on patients' recoveries. Remote therapeutic monitoring (RTM) using wearable devices offers a promising solution to bridge this gap, providing real-time physical function data. This study aims to assess the feasibility and correlation between changes in physical function and daily activity levels using RTM for individuals with operative spinal pathologies.

METHODS

A single-center pilot study involving 21 participants with operative spinal pathologies was conducted at an academic hospital. Participants were provided Bluetooth-enabled Fitbit Inspire 2 activity trackers and asked to wear them daily for 100 days. The Healthcare Recovery Solutions (HRS) mobile application facilitated remote administration of the PROMIS - Physical Function Short Form 6b PROs questionnaire at days 1, 30, and 90. Linear regression, Students' paired T tests, and one-way ANOVA were used to analyze collected data.

RESULTS

Average compliance with RTM was found to be 82.4% compared to only 48% for PROMs. Changes in daily steps were moderately positively correlated with changes in PROs at both 30 and 90 days. Participant satisfaction with RTM was high, and responses indicated greater satisfaction with RTM compared to PROMs.

CONCLUSIONS

RTM offers continuous and objective data collection, presenting a potential solution to the limitations of intermittent clinical assessments and self-reported outcomes. The study demonstrated a moderate correlation between changes in activity levels and changes in PROs, suggesting that RTM data could serve as a surrogate for PROs. Participants' high compliance and satisfaction with RTM underscore its feasibility and potential clinical utility. This study lays the groundwork for larger future investigations into the clinical benefits and broader application of RTM in spine care.

Readability of Patient-Reported Outcomes in Spine Surgery and Implications for Health Literacy

STUDY DESIGN

Observational study.

OBJECTIVE

To evaluate the readability of commonly utilized patient-reported outcome measures (PROMs) in spine surgery.

SUMMARY OF BACKGROUND DATA

Although studies have evaluated patient education materials, discharge instructions, and informed consent forms in spine surgery, there is a dearth of literature on the readability of PROMs despite widespread health illiteracy. Without knowledge of PROM readability, it is unclear whether these measures are able to be understood by the average spine patient.

MATERIALS AND METHODS

We analyzed all commonly utilized nonvisual PROMs within the spinal literature and uploaded PROMs into an online readability calculator. The Flesch Reading Ease Score (FRES) and Simple Measure of Gobbledygook (SMOG) Index were collected. A FRES>79 or SMOG<7 was considered readable by the general population per American Medical Association and Centers for Disease Control guidelines. A stricter threshold recommended in health care (SMOG <6 or FRES>89) was then used to further review readability.

RESULTS

Seventy-seven PROMs were included. Based on FRES, the mean readability of all PROMs was 69.2 ± 17.2 (range, 10-96.4), indicating an average eighth to ninth-grade reading level. The mean readability score categorized by the SMOG Index was 8.12 ± 2.65 (range, 3.1-25.6), representing an eighth-grade reading level. Compared with the reading level of the general population, 49 (63.6%) PROMs are written above the United States literacy level, according to FRES. Using stricter definitions of readability, 8 PROMs were considered readable, including PROM Information System pain behavior (FRES: 96.4 and SMOG: 5.2), PROM Information System sleep disturbance (SMOG: 5.6), Neck Pain and Disability Scale (SMOG: 4.3), and Zung Depression Scale (SMOG: 3.1).

CONCLUSIONS

Most PROMs utilized in spine surgery require an average reading competency far above the average patient's comprehension. This may have a meaningful impact on understanding PROM instruments and may affect the accuracy of complete surveys and the rates of incompletion.

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

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

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

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

Predictive value of the five-repetition sit-to-stand test for outcomes after surgery for lumbar disc herniation: prospective study

OBJECTIVE

It is unknown whether presence of pre-operative objective functional impairment (OFI) can predict post-operative outcomes in patients with lumbar disc herniation (LDH). We aimed to determine whether pre-operative OFI measured by the five-repetition sit-to-stand test (5R-STS) could predict outcomes at 12-months post-discectomy.

METHODS

Adult patients with LDH scheduled for surgery were prospectively recruited from a Dutch short-stay spinal clinic. The 5R-STS time and patient reported outcome measures (PROMs) including Oswestry Disability Index, Roland-Morris Disability Questionnaire, Visual Analogue Scale (VAS) for back and leg pain, EQ-5D-3L health-related quality of life, EQ5D-VAS and ability to work were recorded pre-operatively and at 12-months. A 5R-STS time cut-off of ≥ 10.5 s was used to determine OFI. Mann-Whitney and Chi-square tests were employed to determine significant differences in post-operative outcomes between groups stratified by presence of pre-operative OFI.

RESULTS

We recruited 134 patients in a prospective study. Twelve-month follow-up was completed by 103 (76.8%) patients. Mean age was 53.2 ± 14.35 years and 50 (48.5%) patients were female. Pre-operatively, 53 (51.5%) patients had OFI and 50 (48.5%) did not. Post-operatively, patients with OFI experienced a significantly greater mean change (p < 0.001) across all PROMs compared to patients without OFI, except leg pain (p = 0.176). There were no significant differences in absolute PROMs between groups at 12-months (all p > 0.05).

CONCLUSIONS

The presence of OFI based on 5R-STS time does not appear to decrease a patient's likelihood of experiencing satisfactory post-operative outcomes. The 5R-STS cannot predict how a patient with LDH will respond to surgery at 12-month follow-up.

Patient expectations impact patient-reported outcomes and satisfaction after lumbar fusion

BACKGROUND CONTEXT

Prior studies suggest that patient expectations impact postoperative patient-reported outcomes (PROMs). However, no consensus exists on an appropriate expectations tool.

PURPOSE

To examine the impact of patient expectations using a modified version of the Oswestry Disability Index (ODI) on clinical outcomes and patient satisfaction 1 year after lumbar fusion for degenerative pathologies.

STUDY DESIGN

Prospective longitudinal cohort.

PATIENT SAMPLE

Adults undergoing 1 to 2 level lumbar fusion were identified from four tertiaty spine centers.

OUTCOME MEASURES

ODI, EuroQol-5D, Numeric rating scales for back and leg pain.

METHODS

Preoperatively, patients completed the ODI, as well as a modified ODI reflecting their expected improvement across the 10 ODI items. For example, item 1 in the ODI asks about Pain Intensity at the moment whereas the Expectations ODI asks "One year after surgery, I expect to have…" The difference between this modified ODI score and the baseline ODI score (Baseine ODI minus Expectations ODI) was defined as the Patient Expectation Score. Patients were stratified into tertiles based on their Expectations score into High (HE), Moderate (ME), and Low (LE) Expectations and compared.

RESULTS

There were 30 patients in the HE, 35 in the ME, and 26 in the LE Group, with similar demographics and surgical parameters. Patients in the HE group had worse ODI scores preoperatively (54.96 vs 41.42, p<.001) and were expecting a greater improvement in ODI (43.8 vs 13.5, p<.001). There were fewer patients in the HE group (13, 43%) who reported that they were satisfied with the results compared to either the ME (20, 71%) or LE group (22, 85%, p=.041) despite having similar ODI scores and change in ODI scores 1 year postoperatively.

CONCLUSION

An expectations tool, linked to a disease-specific measure may provide the clinician with a practical method of assessing a patient's expectation of results after treatment and aid in the shared decision-making during the preoperative surgical process.

Reliability and validity of Oswestry Disability Index among patients undergoing lumbar spinal surgery

BACKGROUND

The objective of this study was to explore the internal consistency and factor structure of the Oswestry Disability Index among patients undergoing spinal surgery. The sample consisted of 1,515 patients who underwent lumbar spinal surgery at a university hospital between 2018 and 2021.

METHODS

The patients responded to the Oswestry Disability Index within 2 months before surgery. Cronbach's alpha was used to assess the internal consistency. The factor structure was evaluated using exploratory and confirmatory factor analyses.

RESULTS

The average age of 1,515 patients was 58.5 (SD 15.8) years and 53% were women. The mean ODI score was 43.4% (SD 17.4%). Of the patients, 68% underwent microsurgical excision of the lumbar intervertebral disc displacement or decompression of the lumbar nerve roots. The internal consistency of the Oswestry Disability Index was found to be good, with an alpha of 0.87 (95% CL 0.86 to 0.88). Exploratory factor analysis resulted in unidimensional structure. Item loadings on this retained factor were moderate to substantial for all 10 items. One-factor confirmatory factor analysis model demonstrated an acceptable fit. The correlations between the main factor "disability" and the individual items varied from moderate (0.44) to substantial (0.76). The highest correlations were observed for items "traveling", "personal care", and "social life". The lowest correlations were observed for the item "standing".

CONCLUSIONS

The Oswestry Disability Index is a unidimensional and internally consistent scale that can be used to assess the severity of disability in patients undergoing lumbar spinal surgery. In the studied population, "traveling," "social life," "sex life" and "personal care" were the most important items to define the severity of disability, while "walking" and "standing" were the least important items. The generalizability of the results might be affected by the heterogeneity and modest size of the studied cohort.

TRIAL REGISTRATION

Not applicable.

Postoperative lordosis distribution index, patient reported outcome measures, and revision surgery following transforaminal lumbar interbody fusion

Objective

Lordosis Distribution Index (LDI) is a new radiographic parameter associated with postoperative residual symptoms in patients undergoing Transforaminal Lumbar Interbody Fusion (TLIF). Recently, it has been applied on patients undergoing instrumented spine surgery, however not correlated to Patient Related Outcome Measures (PROMs). This study investigates whether the obtained the postoperative LDI after TLIF surgery correlates with the clinical outcome measured with PROMs.

Methods

This study was based on prospectively obtained data in patients undergoing TLIF throughout 2017 at a Danish university hospital. Medical records and the DaneSpine Database were accessed to obtain preoperative, operative and follow-up data. Primary outcome was Oswestry Disability Index (ODI) 12 months postoperatively. Secondary outcomes included revision rate and additional PROMs.

Results

126 patients were included. 70 patients were classified with normolordosis (56 %), 42 hypolordosis (33 %) and 14 hyperlordosis (11 %). All groups experienced significant radiological changes undergoing surgery. Average reduction in ODI at 12 months postoperatively was -15.3 (±20.0). Minimally clinical important difference was achieved in 68 patients (54.0 %). No significant difference in PROMs between LDI-groups was observed in unadjusted or adjusted analyses. Revision surgery was performed in 8 patients with normolordosis (11.4 %), 7 hypolordosis (16.7 %) and 4 hyperlordosis (28.6 %).

Conclusions

We found no significant correlation between postoperative LDI subgroups of normolordotic, hypo- or hyperlordotic patients and the clinical outcome of posterolateral fusion and TLIF surgery. A trend towards lower rate of revision surgery in the normolordotic group compared to the hypo- and hyperlordotic group was observed.

Radiologic Assessment of Interbody Fusion: A Systematic Review on the Use, Reliability, and Accuracy of Current Fusion Criteria

BACKGROUND

Lumbar interbody fusion (IF) is a common procedure to fuse the anterior spine. However, a lack of consensus on image-based fusion assessment limits the validity and comparison of IF studies. This systematic review aims to (1) report on IF assessment strategies and definitions and (2) summarize available literature on the diagnostic reliability and accuracy of these assessments.

METHODS

Two searches were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Search 1 identified studies on adult lumbar IF that provided a detailed description of image-based fusion assessment. Search 2 analyzed studies on the reliability of specific fusion criteria/classifications and the accuracy assessed with surgical exploration.

RESULTS

A total of 442 studies were included for search 1 and 8 studies for search 2. Fusion assessment throughout the literature was highly variable. Eighteen definitions and more than 250 unique fusion assessment methods were identified. The criteria that showed most consistent use were continuity of bony bridging, radiolucency around the cage, and angular motion <5°. However, reliability and accuracy studies were scarce.

CONCLUSION

This review highlights the challenges in reaching consensus on IF assessment. The variability in IF assessment is very high, which limits the translatability of studies. Accuracy studies are needed to guide innovations of assessment. Future IF assessment strategies should focus on the standardization of computed tomography-based continuity of bony bridging. Knowledge from preclinical and imaging studies can add valuable information to this ongoing discussion.

LEVEL OF EVIDENCE

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Outcome Reporting in Spine Surgery: A Review of Historical and Emerging Trends

The general objectives of spine surgery are to alleviate pain, restore neurologic function, and prevent or treat spinal deformities or instability. The accumulating expanse of outcome measures has allowed us to more objectively quantify these variables and, therefore, gauge the success of treatments, ultimately improving the quality of the delivered health care. It has become increasingly evident that spinal conditions and their accompanying interventions affect all aspects of a patient's life, including their physical, mental, emotional, and social well-being. This underscores the challenge of creating clinically relevant and accurate outcome measures in spine care, and the reason why there is a growing recognition of the importance of subjective measures such as patient-reported outcome measures, that consider a patients' health-related quality of life. Subjective measures provide valuable insights into patient experiences and perceptions of treatment outcomes, whereas objective measures provide a reproducible glimpse into key radiographic and clinical parameters that are associated with a successful outcome. In this narrative review, we provide a detailed analysis of the most common subjective and objective outcome measures employed in spine surgery, with a special focus on their current role as well as the possible future of outcome reporting.

Validation of the Subjective Spine Value: A new single item score for the assessment of spine-specific function

BACKGROUND

Spinal function can be assessed through different patient reported outcome measures (PROMs).

PURPOSE

The aim of the present study was to evaluate a novel single-item score for the assessment of spinal function: The Subjective Spine Value (SSpV). It was hypothesized that the SSpV correlates with the established scores Oswestry disability index (ODI) and Core Outcome Measures Index (COMI).

METHODS

Between 08/2020 and 11/2021 151 consecutive patients were prospectively enrolled and completed a questionnaire with the ODI, COMI as well as the SSpV. Patients were divided into 4 groups depending on their specific pathology (Group 1: Degenerative pathologies, Group 2: Tumor, Group 3: Inflammatory / Infection, Group 4: Trauma). Pearson correlation coefficient was used to evaluate correlation between the SSpV and the ODI and COMI separately. Floor and ceiling effects were evaluated.

RESULTS

Overall, the SSpV correlated significantly with both ODI (p =  < 0.001; r = - 0.640) and COMI (p =  < 0.001; r = - 0.640). This was also observed across all investigated groups (range - 0.420-0.736). No relevant floor or ceiling effects were noticed.

CONCLUSIONS

The SSpV is a valid single-item score for the assessment of spinal function. The SSpV offers a useful tool to efficiently assess spinal function in a variety of spinal pathologies.

LEVEL OF EVIDENCE

I, prospective cohort study.

Values derived from patient reported outcomes in spine surgery: a systematic review of the minimal clinically important difference, substantial clinical benefit, and patient acceptable symptom state

PURPOSE

While patient reported outcome measures (PROMs) define value in spine surgery, several values such as minimal clinically important difference (MCID), substantial clinical benefit (SCB), and patient acceptable symptom state (PASS) help guide the interpretation of PROMs and identify thresholds of clinical significance. Significant variation exists in reported values and their calculation, so the primary objective of this study was to systematically review the spine surgery literature for metrics of clinical significance derived from PROMs.

METHODS

We conducted a query of PubMed/MEDLINE and Scopus databases from inception to January 1, 2023, for studies that derived quantitative metrics (e.g., SCB, MCID, PASS) from PROMs in the setting of spine surgery with minimum 1-year follow-up. Details regarding the specific PROMs were collected including which PROM was measured, whether anchor- or distribution-based methods were utilized, the specific calculations, and the recommended value for a given PROM based on all evaluated calculations.

RESULTS

Thirty-seven studies of 21,780 patients were included. The most commonly evaluated PROM-derived value was the MCID (n = 28), followed by PASS (n = 6) and SCB (n = 4). Twenty-one studies only utilized anchor-based calculations, 15 utilized both anchor-based and distribution-based methods, and one only utilized distribution-based calculations. The most commonly evaluated legacy PROMs were the Oswestry Disability Index (ODI) (N = 11, MCID range 4-20) and visual analog scale back pain (N = 5, MCID range 0.5-4.6). All 10 studies that derived SCB or PASS utilized the receiver operating characteristic methods. Among the six studies deriving a PASS value, four only evaluated ODI, identifying PASS ranging from 5 to 22.

CONCLUSION

While calculated measures of clinical significance such as MCID, PASS, and SCB exist, significant heterogeneity exists in the current literature. Current shortcomings include a wide variability of reported value thresholds across the literature, and limited applicability to more heterogenous patient populations than the targeted cohorts included in published investigations. Continued investigations that apply these methods to heterogenous, large-scale populations can help increase generalizability and validity of these measures.

LEVEL OF EVIDENCE

III.

Review of the Most Cited Patient-Reported Outcome Measure (PROM) Studies Published in the Neurospine Surgical Literature

Patient-reported outcome measures (PROMs) are validated tools that are widely utilized in research and patient care. Their diversity, quality, and application remain matters of peak research interest. This article is a review of the PROMs that were utilized in high-impact publications in the neurospine surgical literature. The 50 most cited articles on the subject were selected and analysed. Most (42 articles) were published in spine journals and, in particular, in the journal Spine (Phila Pa 1976) (28 articles). A total of 34 PROMs were utilized, of which 24 were used only once in single studies. The four most common PROMs were Scoliosis Research Society-22 (SRS-22) (15 articles), Short Form-12 and Short Form-36 (SF-12 and SF-36) (11 articles), Ronald-Morris Disability Questionnaire (RMDQ) (nine articles), and Oswestry Disability Index (ODI) (five articles). Nineteen articles focused on validating translated versions of 11 PROMs to other languages. The languages that had the maximal number of tools translated to amongst the highly cited articles were Italian (six tools), Portuguese (four tools), German (three tools), and Japanese (three tools). The most common diagnoses and the PROMs used for them were back pain and cervical spine disorder (SF-12 and SF-36 (nine articles), RMDQ (eight articles), and ODI (five articles)), and idiopathic scoliosis (SRS-22) (14 articles)). The median (range) article citation number was 137 (78-675). The four most cited PROMs were SRS-22 (2,869), SF-12 and SF-36 (2,558), RMDQ (1,456), and ODI (852). Citation numbers were positively impacted by article age and participant number but not by tool type or clinical diagnosis. In conclusion, a wide range of PROMs was utilized in the 50 most cited publications in the neurospine surgical literature. The majority were disease-specific rather than generic and targeted particular spine pathology. Neurosurgical PROMs were under-represented amongst the most cited articles. Awareness of the PROMs used in high-impact studies may be helpful in tool selection in future research. PROMs are valuable in standardizing subjective outcomes. Their use in research and clinical settings in any validated language is highly encouraged.

Validation of smartphone app-based digital patient reported outcomes in full-endoscopic spine surgery

PURPOSE

Patient reported outcome measures (PROMs) are important tools to assess patient function, pain, disability, and quality of life. We aim to study the efficiency and validity of digital PROMs collection using a smartphone app compared to traditional paper PROMs.

METHODS

Patients undergoing evaluation for full-endoscopic spine surgery were recruited from the outpatient clinic at Harborview Medical Center. Visual analogue scale (VAS), Oswestry disability index (ODI), and EQ5-5D PROMs were administered on paper and through a smartphone app called SpineHealthie. Compliance rates were collected, and PROM results were assessed for correlation between paper and digital methods.

RESULTS

123 patients were enrolled. 57.7% of patients completed paper PROMs, 82.9% completed digital PROMs, and 48.8% completed both. Of the patients that completed both, Spearman's correlation was greatest for VAS leg, ODI, and EQ5 index scores. Correlation was weaker for VAS back pain, neck pain, and upper extremity pain. Patients tended to report lower disability and higher quality of life on the digital PROM compared to the paper PROM.

CONCLUSION

The SpineHealthie app effectively and accurately collects PROMs digitally, showing strong concordance with traditional paper PROMs. We conclude that digital PROMs constitute a promising strategy for monitoring patients after spine surgery over time.

Perioperative Predictors in Patients Undergoing Lateral Lumbar Interbody Fusion for Minimum Clinically Important Difference Achievement

OBJECTIVE

To identify perioperative predictors of minimum clinically important difference (MCID) for patients undergoing lateral lumbar interbody fusion (LLIF) for the patient-reported outcome measures (PROMs) of Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF), visual analog scale (VAS) back, VAS leg, Oswestry Disability Index (ODI), and Patient Health Questionnaire-9 (PHQ-9).

METHODS

Patients undergoing LLIF were identified through retrospective review of a single-surgeon database. Overall MCID achievement was determined as the number of unique patients achieving ΔPROM thresholds of PROMIS-PF = 4.5, VAS back = 2.1, VAS leg = 2.8, ODI = 14.9, and PHQ-9 = 3.0 over a 2-year postoperative period. Univariate and multivariable logistic regression were used to determine perioperative predictors for MCID achievement.

RESULTS

Two-hundred and ninety patients were identified. For PROMIS-PF MCID achievement, increased preoperative PROMIS-PF and postoperative day (POD) 1 VAS pain were significant negative predictors. For VAS back, primary fusion with revision decompression was a negative predictor, whereas increased preoperative VAS back score was a positive predictor of MCID achievement. For VAS leg, increased preoperative VAS leg score was a positive predictor. For ODI, increased POD 0 VAS pain score was a negative predictor, whereas increased preoperative ODI was a positive predictor. For PHQ-9, increased preoperative PHQ-9 score was a positive predictor.

CONCLUSIONS

In patients undergoing LLIF, perioperative predictors for MCID achievement were highly dependent on PROM. Preoperative PROM was the most consistent perioperative predictor for achieving MCID. Increased acute postoperative pain and primary fusion after failed index decompression were significant predictors of failing to achieve MCID. Surgeons may use these findings in prognostication and management of postoperative expectations.

Establishing Minimum Clinically Important Difference Thresholds for Physical Function and Pain in Patients Undergoing Anterior Lumbar Interbody Fusion

OBJECTIVE

To establish minimum clinically important difference (MCID) in anterior lumbar interbody fusion (ALIF) for the physical function patient-reported outcome measures, Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF), 12-Item Short Form (SF-12) physical component score (PCS), Veterans RAND 12 (VR-12) PCS, and pain patient-reported outcome measures visual analog scale (VAS) back and VAS leg through anchor- and distribution-based calculations.

METHODS

Patients undergoing ALIF with preoperative and 6-month Oswestry Disability Index were included. Using Oswestry Disability Index as the anchor, anchor-based calculation methods were the average change, minimum detectable change, and receiver operating characteristic curve methods. Distribution-based methods were the standard error of measurement, reliable change index, effect size, and half of the standard deviation (0.5ΔSD).

RESULTS

Fifty-one patients were identified. Anchor-based methods ranged from 2.9 to 11.5 for PROMIS-PF, 8.2-13.6 for SF-12 PCS, 7.8-16.8 for VR-12 PCS, 0.5-3.9 for VAS back, and 1.0-3.4 for VAS leg. The area under curve ranged from 0.59 (VAS back) to 0.78 (VR-12 PCS). Distribution-based methods ranged from 1.0 to 4.2 for PROMIS-PF, 1.8-12.2 for SF-12 PCS, 1.9-6.2 for VR-12 PCS, 0.4-1.6 for VAS back, and 0.5-1.7 for VAS leg.

CONCLUSIONS

The MCID values greatly relied on the calculation method. The minimum detectable change method was selected as the most appropriate MCID calculation method. The MCID values that may be utilized for ALIF patients are 7.3 for PROMIS-PF, 8.2 for SF-12 PCS, 7.8 for VR-12 PCS, 3.2 for VAS back, and 2.2 for VAS leg.

A systematic review of anterior lumbar interbody fusion (ALIF) versus posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF), posterolateral lumbar fusion (PLF)

PURPOSE

The rate of elective lumbar fusion has continued to increase over the past two decades. However, there remains to be a consensus on the optimal fusion technique. This study aims to compare stand-alone anterior lumbar interbody fusion (ALIF) with posterior fusion techniques in patients with spondylolisthesis and degenerative disc disease through a systematic review and meta-analysis of the available literature.

METHODS

A systematic review was performed by searching the Cochrane Register of Trials, MEDLINE, and EMBASE from inception to 2022. In the two-stage screening process, three reviewers independently reviewed titles and abstracts. The full-text reports of the remaining studies were then inspected for eligibility. Conflicts were resolved through consensus discussion. Two reviewers then extracted study data, assessed it for quality, and analysed it.

RESULTS

After the initial search and removal of duplicate records, 16,435 studies were screened. Twenty-one eligible studies (3686 patients) were ultimately included, which compared stand-alone ALIF with posterior approaches such as posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF), and posterolateral lumbar fusion (PLF). A meta-analysis showed surgical time and blood loss was significantly lower in ALIF than in TLIF/PLIF, but not in those who underwent PLF (p = 0.08). The length of hospital stay was significantly shorter in ALIF than in TLIF, but not in PLIF or PLF. Fusion rates were similar between the ALIF and posterior approaches. The Visual Analogue Scale (VAS) scores for back and leg pain were not significantly different between the ALIF and PLIF/TLIF groups. However, VAS back pain favoured ALIF over PLF at one year (n = 21, MD - 1.00, CI - 1.47, - 0.53), and at two years (2 studies, n = 67, MD - 1.39, CI - 1.67, - 1.11). The VAS leg pain scores (n = 46, MD 0.50, CI 0.12 to 0.88) at two years significantly favoured PLF. The Oswestry Disability Index (ODI) scores at one year were not significantly different between ALIF and the posterior approaches. At two years, ODI scores were also similar between the ALIF and the TLIF/PLIF. However, the ODI scores at two years (2 studies, n = 67, MD - 7.59, CI - 13.33, - 1.85) significantly favoured ALIF over PLF (I2 = 70%). The Japanese Orthopaedic Association Score (JOAS) for low back pain at one year (n = 21, MD - 0.50, CI - 0.78) and two years (two studies, n = 67, MD - 0.36, CI - 0.65, - 0.07) significantly favoured ALIF over PLF. No significant differences were found in leg pain at the 2-year follow-up. Adverse events displayed no significant differences between the ALIF and posterior approaches.

CONCLUSIONS

Stand-alone-ALIF demonstrated a shorter operative time and less blood loss than the PLIF/TLIF approach. Hospitalisation time is reduced with ALIF compared with TLIF. Patient-reported outcome measures were equivocal with PLIF or TLIF. VAS and JOAS, back pain, and ODI scores mainly favoured ALIF over PLF. Adverse events were equivocal between the ALIF and posterior fusion approaches.

Minimum Clinically Important Difference in Patients Undergoing Minimally Invasive Transforaminal Lumbar Interbody Fusion

BACKGROUND

Few studies have established the minimum clinically important difference (MCID) in patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for physical function and pain.

OBJECTIVE

To establish MCID for physical function and pain patient-reported outcome measures (PROMs) for MIS-TLIF through anchor- and distribution-based methods using the Oswestry Disability Index (ODI) as the anchor.

METHODS

Ninety-eight patients undergoing primary MIS-TLIF with preoperative and 1-year postoperative ODI scores were identified. MCID was calculated using anchor- and distribution-based methods. ODI responders were classified as patients who decreased by 1 disability classification. PROMs of Patient-Reported Outcome Measurement Information System-Physical Function (PROMIS-PF), 12-Item Short Form Physical Component Score (SF-12 PCS), Visual Analog Scale (VAS) back/leg, and ODI were collected preoperatively and 1-year postoperatively. Anchor-based methods were average change, minimum detectable change, change difference, receiver operating characteristic curve, and cross-sectional analysis. Distribution-based methods were standard error of measurement, receiver change index, effect size, and 0.5 ∗ ΔSD.

RESULTS

Anchor-based methods ranged from 4.2 to 11.9 for PROMIS-PF, 6.0 to 15.8 for SF-12 PCS, 1.8 to 4.6 for VAS back, and 2.1 to 4.0 for VAS leg. The area under the curve for receiver operating characteristic analysis ranged from 0.66 to 0.81. Distribution-based methods ranged from 1.1 to 3.9 for PROMIS-PF, 1.6 to 10.4 for SF-12 PCS, 0.5 to 1.6 for VAS back, and 0.6 to 1.8 for VAS leg.

CONCLUSION

Patients undergoing MIS-TLIF had a wide range of MCID values. The receiver operating characteristic curve was selected as the most clinically appropriate method. The corresponding MCID values were 4.2 for PROMIS-PF, 6.8 for SF-12 PCS, 1.8 for VAS back, and 2.4 for VAS leg.

Emerging Need for PROMs to Measure the Impact of Spine Disorders on Overall Health and Well-being: Measuring Expectations as an Example for Lumbar Degenerative Spondylolisthesis

Background: Assessing the impact of spine disorders such as lumbar degenerative spondylolisthesis (LDS) on overall health is a component of quality of care that may not be comprehensively captured by spine-specific and single-attribute patient-reported outcome measures (PROMs). Purpose: We sought to compare PROMs to the Lumbar Surgery Expectations Survey ("Expectations Survey"), which addresses multiple aspects of health and well-being, and to compare the relevance of surgeon-selected versus survey-selected Patient-Reported Outcomes Measurement Information System (PROMIS) items to LDS. Methods: In a cross-sectional study, 379 patients with LDS preoperatively completed the Expectations Survey, Numerical Rating Pain Scales, Oswestry Disability Index (ODI), and PROMIS computer-adaptive physical function, pain, and mental health surveys. Expectations Survey scores were compared to PROMs with correlation coefficients (indicating strengths of relationships) and probability values (indicating associations by chance). Surgeons reviewed physical function questions to identify those particularly relevant to LDS. Results: Patients' mean age was 67 years, 64% were women, and 83% had single-level and 17% had multiple-level LDS. Probability values between the Expectations Survey and PROMs were reliable, but strengths of relationships were only mild to moderate, indicating PROMs did not comprehensively capture the impact of LDS. None of the surgeon-selected PROMIS physical function questions were posed to patients. Conclusion: This cross-sectional study found PROMs to be reliably associated but not strongly correlated with the Expectations Survey, which addresses the whole-patient impact of LDS. New measures that complement PROMIS and ODI should be developed to capture the whole-person effects of LDS and permit attribution of LDS treatments to overall health.

Impact of Sleep Disturbance on Clinical Outcomes in Lumbar Decompression

OBJECTIVE

To examine the impact of Patient-Reported Outcomes Measurement Information System (PROMIS) Sleep Disturbance (PROMIS-SD) on clinical outcomes in patients undergoing lumbar decompression.

METHODS

Patients undergoing lumbar decompression with preoperative PROMIS-SD scores were retrospectively included. Patients were separated into 2 cohorts: none to slight sleep disturbance (PROMIS-SD <55) and mild to severe sleep disturbance (PROMIS-SD ≥55). Patient-reported outcome measures including PROMIS Physical Function, PROMIS Anxiety, PROMIS Pain Interference, PROMIS SD, 9-item Patient Health Questionnaire, visual analog scale back/leg, and Oswestry Disability Index were collected preoperatively and up to 1 year postoperatively.

RESULTS

Of 87 patients identified, 48 patients had PROMIS-SD scores ≥55. Regardless of preoperative PROMIS-SD score, patients reported significant improvement in physical function, anxiety, pain interference, depression, pain, and disability outcomes in at least 1 time point. Patients in the PROMIS-SD ≥55 cohort reported postoperative improvement in sleep disturbance. Patients in the PROMIS-SD <55 cohort reported superior preoperative patient-reported outcome measures in all domains and superior postoperative improvement in pain interference and sleep disturbance. Minimum clinically important difference attainment rates were higher in the PROMIS-SD ≥55 cohort in physical function, anxiety, pain interference, sleep disturbance, and pain.

CONCLUSIONS

Patients undergoing lumbar decompression demonstrated significant postoperative improvement in most clinical outcomes regardless of preoperative sleep disturbance. Patients with mild to severe sleep disturbance had higher minimum clinically important difference attainment rates for physical function, mental function, and pain. Patients undergoing lumbar decompression with greater preoperative sleep disturbance may experience more clinically noticeable improvement.

Electronic versus paper patient-reported outcome measure compliance rates: A retrospective analysis

OBJECTIVE

Patient-reported outcome measures (PROMs) are key tools used to inform clinical research and patient-centered care. Application of data collected from PROMs, however, may be limited by incomplete responses, and little is known regarding the efficacy of varied PROM delivery methods. The objective of this study was to compare PROMs compliance when delivered via paper and electronic formats.

METHODS

Elective adult spinal deformity patients were screened for inclusion. Data collected included demographics, type of surgery, PROMs compliance, and discharge care. Descriptive statistics and multivariate analysis (MVA) were performed to compare pre- and postoperative compliance rates.

RESULTS

Of the 474 included patients, 177 were administered paper PROMs, while 297 were electronic. Preoperatively, 101 patients (57.1%) had any portion of their paper PROMs available; 179 (60.3%) had any of their electronic PROMs available (p = 0.492). Among all patients, 76 (42.9%) and 170 (57.2%) had all of their completed preop PROMs available (p = 0.003). Among patients with any of their preop PROMs completed, 75.2% with paper and 95.0% with electronic were completed in their entirety (p < 0.001). Similar trends were observed among postoperative PROMs. MVA demonstrated electronic delivery as the only significant correlate with pre- and post-operative PROMs compliance (p < 0.001 and p = 0.003, respectively).

CONCLUSIONS

No differences were observed across modalities when considering any available PROMs, yet electronic PROM delivery was associated with higher completion of PROMs. In order to improve the quality of patient-reported data, electronic delivery with alternative methods of quality improvement may be considered to increase PROMs retention rates.

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.

ODI <25 Denotes Patient Acceptable Symptom State After Minimally Invasive Lumbar Spine Surgery

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

To determine the Oswestry Disability Index (ODI) cutoff for achieving Patient Acceptable Symptom State (PASS) at one year following minimally invasive lumbar spine surgery.

SUMMARY OF BACKGROUND DATA

An absolute score denoting PASS, rather than a change score denoting minimal clinically important difference (MCID), might be a better metric to assess clinical outcomes.

MATERIALS AND METHODS

Patients who underwent primary minimally invasive transforaminal lumbar interbody fusion or decompression were included. The outcome measure was ODI. The anchor question was the Global Rating Change: "Compared with preoperative, you feel (1) much better, (2) slightly better, (3) same, (4) slightly worse, or (5) much worse." For analysis, it was collapsed to a dichotomous outcome variable (acceptable=response of 1 or 2, unacceptable=response of 3, 4, or 5). Proportion of patients achieving PASS and the ODI cutoff using receiver operating characteristic curve analyses were assessed for the overall cohort as well as subgroups based on age, sex, type of surgery, and preoperative ODI. Differences between the PASS and MCID metrics were analyzed.

RESULTS

A total of 137 patients were included. In all, 87% of patients achieved PASS. Patients less than or equal to 65 years and those undergoing fusion were more likely to achieve PASS. The receiver operating characteristic curve analysis revealed an ODI cutoff of 25.2 to achieve PASS (area under the curve: 0.872, sensitivity: 82%, specificity: 83%). The subgroup analyses based on age, sex, and preoperative ODI revealed area under the curve >0.8 and ODI threshold values consistent between 25.2 and 25.5 (except 28.4 in patients with preoperative ODI >40). PASS was found to have significantly higher sensitivity compared with MCID (82% vs. 69%, P =0.01).

CONCLUSIONS

Patients with ODI <25 are expected to achieve PASS, irrespective of age, sex, and preoperative disability. PASS was found to have significantly higher sensitivity than MCID.

LEVEL OF EVIDENCE

3.

Influence of Predominant Neck versus Arm Pain on Clinical Outcomes in Cervical Disc Replacement

OBJECTIVE

We aim to compare the postoperative clinical outcomes, through patient-reported outcome measures (PROMs) and minimum clinically important difference (MCID), in patients undergoing cervical disc replacement (CDR) with preoperative predominant neck pain (pNP) or arm pain (pAP).

METHODS

Patients undergoing primary CDR were separated into pNP or pAP cohorts. Demographic, perioperative characteristics, PROMs at preoperative and postoperative time points, and MCID were compared using inferential statistics. Assessed PROMs included Patient-Reported Outcome Measurement Information System-Physical Function (PROMIS-PF), 12-Item Short Form Physical/Mental Component Score (SF-12 PCS/MCS), visual analog scale (VAS) neck, VAS arm, and Neck Disability Index.

RESULTS

There were a total of 84 patients, with 54 patients in the pNP cohort. The pNP cohort showed significant postoperative improvement in all PROMs, except for 6-week and 1-year SF-12 PCS, 1-year SF-12 MCS, and 6-month VAS arm score (P ≤ 0.023, all). The pAP cohort showed significant postoperative improvement in all PROMs, apart from 6-month to 1-year SF-12 PCS, and all SF-12 MCS (P ≤ 0.041, all). Greater MCID achievement rates were found in the pNP cohort for SF-12 MCS (P = 0.030). The pAP cohort had higher MCID achievement rates in VAS arm score and Neck Disability Index (P ≤ 0.046, all).

CONCLUSIONS

Independent of predominant pain location, patients reported improved physical function, pain, and disability outcomes. Patients with pNP had higher MCID achievement rates in mental function. Patients with pAP had higher rates of MCID achievement in arm pain and disability outcomes. Considering the predominant location of preoperative pain may be helpful in managing expectations for patients undergoing CDR.

The Effect of the Severity of Preoperative Leg Pain on Patient-Reported Outcomes, Minimum Clinically Important Difference Achievement, and Patient Satisfaction After Minimally Invasive Transforaminal Lumbar Interbody Fusion

OBJECTIVE

To compare patient-reported outcome measures (PROMs), satisfaction, and minimum clinically important difference (MCID) achievement after minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in patients stratified by preoperative leg pain.

METHODS

Patients undergoing MIS-TLIF were collected through retrospective review of a prospectively maintained single-surgeon database. PROMs administered preoperatively/postoperatively included Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF), visual analog scale (VAS) back/leg pain, Oswestry Disability Index (ODI), and 12-Item Short Form (SF-12) Physical/Mental Component Score (PCS/MCS). Patients were grouped based on preoperative VAS leg scores: VAS leg ≤7 or VAS leg >7. Inferential statistics were used to compare PROMs, MCID achievement rates, and postoperative satisfaction between groups.

RESULTS

A total of 562 patients were eligible (168 VAS leg score ≤7; 394 VAS leg score >7). Significant differences between cohorts in postoperative mean PROMs were noted for PROMIS-PF at 6 weeks/2 years, SF-12 PCS at 6 weeks/2 years, SF-12 MCS at 6 weeks/12 weeks/6 months/1 year, VAS back score at 6 weeks/12 weeks/6 months, VAS leg score at 6 weeks/12 weeks/6 months/2 years and ODI at all postoperative time points (P < 0.045, all). In the VAS leg score >7 cohort, a greater proportion achieving MCID for VAS leg score at all postoperative time points and ODI at 12 weeks (P < 0.010, all). Postoperative satisfaction was greater in VAS back score ≤7 cohort for VAS leg score at 6 weeks/12 weeks/6 months/2 years, VAS back score at 12 weeks/2 years, and ODI at 6 weeks/12 weeks/6 months/2 years (P < 0.046, all).

CONCLUSIONS

Patients with severe preoperative leg pain showed worse postoperative PROM scores and patient satisfaction for disability and back/leg pain. MCID achievement rates across cohorts were similar. Patients with severe leg pain may have expectations for surgical benefits incongruent with their postoperative outcomes, and physicians may seek to manage the preoperative expectations of their patients to reflect likely outcomes after MIS-TLIF.

Determination of Patient Acceptable Symptom State for the Oswestry Disability Index Score in Patients Who Underwent Minimally Invasive Discectomy for Lumbar Disc Herniation: 2-Year Follow-up Data from a Randomized Controlled Trial

OBJECTIVE

We aim to determinate the patient acceptable symptom state (PASS) for the Oswestry Disability Index (ODI) score in patients undergoing minimally invasive discectomy for the treatment of lumbar disc herniation.

METHODS

A post hoc analysis of prospectively collected, 2-year follow-up data was conducted. The anchor for determination of PASS was the European Quality of Life Visual Analog Scales question, and the Pearson correlation test was performed to evaluate its validity. The receiver operating characteristics (ROC) curve analysis was conducted to determine the PASS thresholds for ODI and its discriminative ability assessment. Sensitivity analyses were also carried out for alternative definition of PASS, different follow-up periods, and different subgroups.

RESULTS

A total of 222 patients (92.1%) completed the 2-year follow-up, 92.8% of whom considered their state to be acceptable. The area under the ROC curve (AUC) were all >0.8, indicating a high discriminative ability. The PASS threshold for the ODI was suggested to be 5 at 6 months (AUC: 0.80; sensitivity: 79.0%, specificity: 73.7%) and 2 years (AUC: 0.98; sensitivity: 90.3%, specificity: 100%) postoperatively. Despite some variations found in different body mass index and baseline ODI subgroups, sensitivity analysis showed that the above-mentioned threshold was robust.

CONCLUSIONS

An ODI of 5 was noted to be the PASS threshold for patients received minimally invasive discectomy for the treatment of LDH. This ODI threshold was robust, and therefore recommended as the ultimate goal of minimally invasive treatment for LDH, which can help to present results of clinical research at an individual level.

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.

Utilizing Data from Wearable Technologies in the Era of Telemedicine to Assess Patient Function and Outcomes in Neurosurgery: Systematic Review and Time-Trend Analysis of the Literature

BACKGROUND

The COVID-19 pandemic has driven the increased use of telemedicine and the adoption of wearable technology in neurosurgery. We reviewed studies exploring the use of wearables on neurosurgical patients and analyzed wearables' scientific production trends.

METHODS

The review encompassed PubMed, EMBASE, Web of Science, and Cochrane Library. Bibliometric analysis was performed using citation data of the included studies through Elsevier's Scopus database. Linear regression was utilized to understand scientific production trends. All analyses were performed on R 4.1.2.

RESULTS

We identified 979 studies. After screening, 49 studies were included. Most studies evaluated wearable technology use for patients with spinal pathology (n = 31). The studies were published over a 24-year period (1998-2021). Forty-seven studies involved wearable device use relevant to telemedicine. Bibliometric analysis revealed a compounded annual growth rate of 7.3%, adjusted for inflation, in annual scientific production from 1998 to 2021 (coefficient=1.3; 95% Confidence Interval = [0.7, 1.9], P < 0.01). Scientific production steadily increased in 2014 (n = 1) and peaked from 2019 (n = 8) to 2021 (n = 13) in correlation with the COVID-19 pandemic. Publications spanned 34 journals, averaged 24.4 citations per article, 3.0 citations per year per article, and 8.3 authors per article.

CONCLUSION

Wearables can provide clinicians with objective measurements to determine patient function and quality of life. The rise in articles related to wearables in neurosurgery demonstrates the increased adoption of wearable devices during the COVID-19 pandemic. Wearable devices appear to be a key component in this era of telemedicine and their positive utility and practicality are increasingly being realized in neurosurgery.

Does Preoperative Symptom Duration Impact Clinical Outcomes After Minimally Invasive Transforaminal Lumbar Interbody Fusion in the Ambulatory Setting?

BACKGROUND

The effect of prolonged symptom duration in patients undergoing ambulatory MIS-TLIF on postoperative clinical outcomes has not been well studied. We aim to compare symptom duration of pain and/or weakness on postoperative outcomes in patients undergoing outpatient MIS-TLIF.

METHODS

Patients undergoing outpatient MIS-TLIF were gathered in a single-surgeon database. Exclusion criteria were patients missing onset of symptoms, date of surgery, or diagnosis of malignancy, trauma, or infection. Patients were grouped by symptoms <1 year or symptoms ≥1 year. Propensity score matching for demographics was utilized. Minimal clinically important difference (MCID) achievement was calculated by comparing change in patient-reported outcome measures (PROMs) to previously established values. Inferential statistics for demographics, perioperative characteristics, PROMs, and MCID were utilized to compare between groups and/or postoperative improvement.

RESULTS

After matching, there were a total of 56 patients, with 30 patients with symptoms <1-year. The <1-year cohort reported significant improvement in all time points in VAS back/leg and 12-week/6-months in ODI. The ≥1-year cohort demonstrated significant improvement in 6-month Patient-Reported Outcomes Measurement-Information System Physical Function, 6-week to 1-year VAS back, 6-week VAS leg, and 6-month ODI. The <1-year cohort had higher MCID attainment rates in 1-year VAS back/leg.

CONCLUSIONS

Independent of symptom duration, patients reported significant improvement in back pain at all postoperative periods. Patients presenting with shorter symptom duration consistently reported significant improvement in leg pain postoperatively. Patients with shorter symptom duration demonstrated greater MCID achievement in back and leg pain. Patients indicated for outpatient MIS-TLIF may benefit more from earlier intervention following onset of symptoms.

Level-specific Perioperative and Clinical Outcome Comparison: Cervical Disk Replacement Versus Anterior Cervical Diskectomy and Fusion at C5-C6 in Patients With Myeloradiculopathy

INTRODUCTION

This study compares perioperative and postoperative clinical outcomes in patients undergoing anterior cervical diskectomy and fusion (ACDF) or cervical disk replacement (CDR) at C5-C6 in patients with myeloradiculopathy.

METHODS

Primary, elective, single-level CDR or ACDF procedures at C5-C6 for patients with myeloradiculopathy were included. Patient-reported outcome measures (PROMs) included visual analog scale (VAS) neck, VAS arm, Neck Disability Index (NDI), Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF), and Short-Form 12-Item Physical Composite Score (SF-12 PCS) collected at preoperative/6-week/12-week/6-month/1-year time points. Surgical cohorts were assessed for differences in demographics/perioperative characteristics using the chi square test and unpaired Student t-test for categorical and continuous variables, respectively. Achievement of minimum clinically important difference (MCID) was determined by comparing ΔPROMs with established thresholds. Outcome measures were compared at postoperative time points with the Student t-test, and improvement from preoperative baseline was assessed with a paired sample t-test.

RESULTS

One hundred thirty-seven patients were included, 43 CDR and 94 ACDF. CDR patients demonstrated significantly reduced surgical times (46.3 versus 55.1 minutes), estimated blood loss (24.4 versus 43.6 mL), revision surgery rates (0.0% versus 5.3%), postoperative length of stay (8.9 versus 23.0 hours), and postoperative narcotic consumption (P < 0.017, all). Complication rates and mean PROMs did not differ between cohorts. The CDR cohort markedly improved from baseline for all PROMs postoperatively except SF-12 PCS/PROMIS-PF at 6 weeks. The ACDF cohort markedly improved at each time point except VAS arm at 1 year, NDI at 6 weeks/1 year, and SF-12 PCS/PROMIS-PF at 6 weeks. A majority of both cohorts achieved overall MCID for VAS neck/NDI/PROMIS-PF. MCID achievement rates did not differ except NDI at 12 weeks/1 year and SF-12 PCS at 6 months, both favoring CDR.

DISCUSSION

Both procedural cohorts demonstrated similar long-term clinical outcomes for arm/neck pain and physical function; however, patients undergoing CDR at C5-C6 demonstrated an improved ability to maintain 1-year postoperative progress for neck disability with improved 1-year NDI MCID achievement. The CDR cohort, in addition, demonstrated an improved perioperative profile and reduced rate of revision surgery.

Pain After Preoperative Ultrasound Guided Hip Injections for Total Hip Arthroplasty: A Pilot Randomized Controlled Trial

Introduction. Hip replacement is a frequently performed and highly successful treatment for patients with end stage osteoarthritis. Advances in technique and pain management have allowed for rapid mobilization and early discharge after surgery. We hypothesize that pre-incision intra-articular injection of local anesthetic with epinephrine under image guidance combined with post incision peri-articular injection (PAI) may be more effective than PAI alone. Methods. A prospective, randomized, controlled, comparative investigation at a single institution of 41 patients undergoing THA who received standard 30 mL post-arthrotomy, PAI of ropivacaine with epinephrine under direct visualization after prosthesis implantation before closure or an equivalent dose divided into a 10 mL pre-incision, ultrasound guided intra-articular injection and a 20 mL post-arthrotomy PAI. Results. 42 patients were included in this study before its early conclusion with 22 patients in the treatment group and 20 in the control group. There were no significant differences in age, BMI or ASA scores. Additionally, there were no significant differences noted when comparing groups by postoperative outcome measures including OMME, EBL, OR time, PACU minutes, and first and last PACU pain score. Furthermore, there were no significant differences in the PROMs evaluated. Discussion. The addition of ultrasound guided pre-incision intra-articular injection to the standard PAI had no benefit when compared with standard PAI during a THA. Portable mobile phone based ultrasound devices provide a cost effective way to perform musculoskeletal blocks, and further studies on their use and comparative accuracy is warranted. A novel technique for confirmation of injection location is described.

Sleep disturbance, dyspnea, and anxiety following total joint arthroplasty: an observational study

BACKGROUND

Patient-Reported Outcomes Measurement Information System (PROMIS) domains for sleep disturbance, anxiety, and dyspnea have been under-reported for total joint arthroplasty (TJA). The aims of this study were to report postoperative differences for these domains based on TJA location and chronic pain state. We also investigated whether these domains were associated with physical function and pain interference outcomes.

METHODS

This was a retrospective, observational study of patients who underwent hip, knee, or shoulder TJA (primary and revision surgeries) at a single academic tertiary referral center. A subset of these patients completed an email-based survey for chronic pain grade (Chronic Pain Grade Scale-Revised) and sleep disturbance, anxiety, dyspnea, physical function, and pain interference (PROMIS short forms). Pre-operative and operative data were extracted from the electronic health record. Data analysis investigated PROMIS domains for differences in TJA location and chronic pain grade. Hierarchical linear regression determined associations of these domains with physical function and pain interference.

RESULTS

A total of 2638 individuals provided informed consent and completed the email survey. In the ANOVA models for sleep disturbance, anxiety, and dyspnea, there was no location by chronic pain grade interaction (p > 0.05) and no difference based on TJA location (p > 0.05). There were differences for chronic pain grade (p < 0.01). The poorest postoperative outcome score for each domain was associated with high impact chronic pain. Furthermore, sleep disturbance and dyspnea had the strongest associations with physical function and pain interference (p < 0.01).

CONCLUSIONS

Sleep disturbance, anxiety, and dyspnea did not vary based on TJA location, but were associated with postoperative chronic pain grade. Sleep disturbance and dyspnea were strongly associated with commonly reported outcomes of physical function and pain interference. These findings provide guidance for those interested in expanding TJA outcome assessment to include sleep disturbance, anxiety, and/or dyspnea.

Analysis of Patient-reported Outcomes Measures Used in Lumbar Fusion Surgery Research for Degenerative Spondylolisthesis

STUDY DESIGN

Meta-analyses.

OBJECTIVE

This study aims to document the most common Patient-reported Outcome Measures (PROMs) used to assess lumbar fusion surgery outcomes and provide an estimate of the average improvement following surgical treatment.

SUMMARY OF BACKGROUND DATA

As health care institutions place more emphasis on quality of care, accurately quantifying patient perceptions has become a valued tool in measuring outcomes. To this end, greater importance has been placed on the use of PROMs. This is a systemic review and meta-analysis of randomly controlled trials published between 2014 and 2019 assessing surgical treatment of degenerative spondylolisthesis.

METHODS

A fixed effect size model was used to calculate mean difference and a 95% confidence interval (95% CI). Linear regression was used to calculate average expected improvement, adjusted for preoperative scores.

RESULTS

A total of 4 articles (7 study groups) were found for a total of 444 patients. The 3 most common PROMs were Oswestry Disability Index (ODI) (n=7, 100%), Short-Form-12 or Short-Form-36 (SF-12/36) (n=4, 57.1%), and visual analog scale-back pain (n=3, 42.8%). Pooled average improvement was 24.12 (95% CI: 22.49-25.76) for ODI, 21.90 (95% CI: 19.71-24.08) for SF-12/36 mental component score, 22.74 (95% CI: 20.77-24.71) for SF-12/36 physical component score, and 30.87 (95% CI: 43.79-47.97) for visual analog scale-back pain. After adjusting for preoperative scores, patients with the mean preoperative ODI (40.47) would be expected to improve by 22.83 points postoperatively.

CONCLUSIONS

This study provides a range of expected improvement for common PROMs used to evaluate degenerative spondylolisthesis with the goal of equipping clinicians with a benchmark value to use when counseling patients regarding surgery. In doing so, it hopes to provide a comparison point by which to judge individual patient improvement.

LEVEL OF EVIDENCE

Level II.

Physical functioning outcome measures in the lumbar spinal surgery population and measurement properties of the physical outcome measures: protocol for a systematic review

INTRODUCTION

Low back pain can lead to substantial decline in physical functioning. For disabling pain not responsive to conservative management, surgical intervention can enhance physical functioning. Measurements of physical functioning include patient-reported outcome measures and physical outcome measures using evaluations of impairments, performance on a standardised task or activity in a natural environment. Selecting outcome measures with adequate measurement properties is fundamental to evaluating effectiveness of interventions. The purpose of this systematic review is to identify outcome measures (patient reported and physical) used to evaluate physical functioning (stage 1) and assess the measurement properties of physical outcome measures of physical functioning (stage 2) in the lumbar spinal surgery population.

METHODS AND ANALYSIS

This protocol aligns with the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines and Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Using a two-staged approach, searches will be performed in MEDLINE, EMBASE, Health and Psychosocial Instruments, CINAHL, Web of Science, Scopus, PEDro and the grey literature from inception until 15 December 2021. Stage 1 will identify studies evaluating physical functioning with patient-reported or physical outcome measures in the lumbar spinal surgery population. Stage 2 will search for studies evaluating measurement properties (validity, reliability, responsiveness) of the physical outcome measures identified in stage 1 in the lumbar spinal surgery population. Two independent reviewers will evaluate studies for inclusion, extract data, assess risk of bias (COSMIN risk of bias tool and checklist) and quality of evidence (modified Grading of Recommendations Assessment, Development and Evaluation approach). Results for each measurement property per physical outcome measure will be quantitatively pooled if there is adequate clinical and methodological homogeneity or qualitatively synthesised if there is high heterogeneity in studies.

ETHICS AND DISSEMINATION

Ethics approval is not required. Results will be disseminated through peer-reviewed journal publication and conference presentation.

PROSPERO REGISTRATION NUMBER

CRD42021293880.

ALIF Versus TLIF for L5-S1 Isthmic Spondylolisthesis: ALIF Demonstrates Superior Segmental and Regional Radiographic Outcomes and Clinical Improvements Across More Patient-reported Outcome Measures Domains

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The purpose of this study was to compare segmental and regional radiographic parameters between anterior interbody fusion (ALIF) and posterior interbody fusion (TLIF) for treatment of L5-S1 isthmic spondylolisthesis, and to assess for changes in these parameters over time. Secondarily, we sought to compare clinical outcomes via patient-reported outcome measures (PROMs) between techniques and within groups over time.

SUMMARY OF BACKGROUND DATA

Isthmic spondylolistheses are frequently treated with interbody fusion via ALIF or TLIF approaches. Robust comparisons of radiographic and clinical outcomes are lacking.

METHODS

We reviewed pre- and postoperative radiographs as well as Patient-Reported Outcomes Measurement Information System (PROMIS) elements for patients who received L5-S1 interbody fusions for isthmic spondylolisthesis in the Mass General Brigham (MGB) health system (2016-2020). Intraclass correlation testing was used for reliability assessments; Mann-Whitney U tests and Sign tests were employed for intercohort and intracohort comparative analyses, respectively.

RESULTS

ALIFs generated greater segmental and L4-S1 lordosis than TLIF, both at first postoperative visit (mean 26 days [SE = 4]; 11.3° vs. 1.3°, P  < 0.001; 6.2° vs. 0.3°, P  = 0.005) and at final follow-up (mean 410days [SE = 45]; 9.6° vs. 0.2°, P < 0.001; 7.9° vs. 2.1°, P = 0.005). ALIF also demonstrated greater increase in disc height than TLIF at first (9.6 vs. 5.5 mm, P < 0.001) and final follow-up (8.7 vs. 3.6 mm, P < 0.001). Disc height was maintained in the ALIF group but decreased over time in the TLIF cohort (ALIF 9.6 vs. 8.7 mm, P = 0.1; TLIF 5.5 vs. 3.6 mm, P < 0.001). Both groups demonstrated improvements in Pain Intensity and Pain Interference scores; ALIF patients also improved in Physical Function and Global Health - Physical domains.

CONCLUSION

ALIF generates greater segmental lordosis, regional lordosis, and restoration of disc height compared to TLIF for treatment of isthmic spondylolisthesis. Additionally, ALIF patients demonstrate significant improvements across more PROMs domains relative to TLIF patients.Level of Evidence: 3.

Measuring functional outcomes in major trauma: can we do better?

PURPOSE

There is relatively limited large scale, long-term unified evidence to describe how quality of life (QoL) and functional outcomes are affected after polytrauma. The aim of this study is to review validated measures available to assess QoL and functional outcomes and make recommendations on how best to assess patents after major trauma.

METHODS

PubMed and EMBASE databases were interrogated to identify suitable patient-reported outcome measures (PROMs) for use in major trauma, and current practice in their use globally.

RESULTS

Overall, 81 papers met the criteria for inclusion and evaluation. Data from these were synthesised. A full set of validated PROMs tools were identified for patients with polytrauma, as well as critique of current tools available, allowing us to evaluate practice and recommend specific outcome measures for patients following polytrauma, and system changes needed to embed this in routine practice moving forward.

CONCLUSION

To achieve optimal outcomes for patients with polytrauma, we will need to focus on what matters most to them, including their needs (and unmet needs). The use of appropriate PROMs allows evaluation and improvement in the care we can offer. Transformative effects have been noted in cases where they have been used to guide treatment, and if embedded as part of the wider system, it should lead to better overall outcomes. Accordingly, we have made recommendations to this effect. It is time to seize the day, bring these measures even further into our routine practice, and be part of shaping the future.

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.

Minimally invasive versus open lumbar spinal fusion: a matched study investigating patient-reported and surgical outcomes

OBJECTIVE

With the expanding indications for and increasing popularity of minimally invasive surgery (MIS) for lumbar spinal fusion, large-scale outcomes analysis to compare MIS approaches with open procedures is warranted.

METHODS

The authors queried the Quality Outcomes Database for patients who underwent elective lumbar fusion for degenerative spine disease. They performed optimal matching, at a 1:2 ratio between patients who underwent MIS and those who underwent open lumbar fusion, to create two highly homogeneous groups in terms of 33 baseline variables (including demographic characteristics, comorbidities, symptoms, patient-reported scores, indications, and operative details). The outcomes of interest were overall satisfaction, decrease in Oswestry Disability Index (ODI), and back and leg pain, as well as hospital length of stay (LOS), operative time, reoperations, and incidental durotomy rate. Satisfaction was defined as a score of 1 or 2 on the North American Spine Society scale. Minimal clinically important difference (MCID) in ODI was defined as ≥ 30% decrease from baseline. Outcomes were assessed at the 3- and 12-month follow-up evaluations.

RESULTS

After the groups were matched, the MIS and open groups consisted of 1483 and 2966 patients, respectively. Patients who underwent MIS fusion had higher odds of satisfaction at 3 months (OR 1.4, p = 0.004); no difference was demonstrated at 12 months (OR 1.04, p = 0.67). Lumbar stenosis, single-level fusion, higher American Society of Anesthesiologists Physical Status Classification System grade, and absence of spondylolisthesis were most prominently associated with higher odds of satisfaction with MIS compared with open surgery. Patients in the MIS group had slightly lower ODI scores at 3 months (mean difference 1.61, p = 0.006; MCID OR 1.14, p = 0.0495) and 12 months (mean difference 2.35, p < 0.001; MCID OR 1.29, p < 0.001). MIS was also associated with a greater decrease in leg and back pain at both follow-up time points. The two groups did not differ in operative time and incidental durotomy rate; however, LOS was shorter for the MIS group. Revision surgery at 12 months was less likely for patients who underwent MIS (4.1% vs 5.6%, p = 0.032).

CONCLUSIONS

In patients who underwent lumbar fusion for degenerative spinal disease, MIS was associated with higher odds of satisfaction at 3 months postoperatively. No difference was demonstrated at the 12-month follow-up. MIS maintained a small, yet consistent, superiority in decreasing ODI and back and leg pain, and MIS was associated with a lower reoperation rate.

One-Year Clinical Outcomes of Minimal-Invasive Dorsal Percutaneous Fixation of Thoracolumbar Spine Fractures

Introduction: Minimal-invasive instrumentation techniques have become a workhorse in spine surgery and require constant clinical evaluations. We sought to analyze patient-reported outcome measures (PROMs) and clinicopathological characteristics of thoracolumbar fracture stabilizations utilizing a minimal-invasive percutaneous dorsal screw-rod system. Methods: We included all patients with thoracolumbar spine fractures who underwent minimal-invasive percutaneous spine stabilization in our clinics since inception and who have at least 1 year of follow-up data. Clinical characteristics (length of hospital stay (LOS), operation time (OT), and complications), PROMs (preoperative (pre-op), 3-weeks postoperative (post-op), 1-year postoperative: eq5D, COMI, ODI, NRS back pain), and laboratory markers (leucocytes, c-reactive protein (CRP)) were analyzed, finding significant associations between these study variables and PROMs. Results: A total of 68 patients (m: 45.6%; f: 54.4%; mean age: 76.9 ± 13.9) were included. The most common fracture types according to the AO classification were A3 (40.3%) and A4 (40.3%), followed by B2 (7.46%) and B1 (5.97%). The Median American Society of Anesthesiologists (ASA) score was 3 (range: 1−4). Stabilized levels ranged from TH4 to L5 (mean number of targeted levels: 4.25 ± 1.4), with TH10-L2 (12/68) and TH11-L3 (11/68) being the most frequent site of surgery. Mean OT and LOS were 92.2 ± 28.2 min and 14.3 ± 6.9 days, respectively. We observed 9/68 complications (13.2%), mostly involving screw misalignments and loosening. CRP increased from 24.9 ± 33.3 pre-op to 34.8 ± 29.9 post-op (p < 0.001), whereas leucocyte counts remained stable. All PROMs showed a marked significant improvement for both 3-week and 1-year evaluations compared to the preoperative situation. Interestingly, we did not find an impact of OT, LOS, lab markers, complications, and other clinical characteristics on PROMs. Notably, a higher number of stabilized levels did not affect PROMs. Conclusions: Minimal-invasive stabilization of thoracolumbar fractures utilizing a dorsal percutaneous approach resulted in significant PROM outcome improvements, although we observed a complication rate of 13.2% for up to 1 year of follow-up. PROMs were not significantly associated with clinicopathological characteristics, technique-related variables, or the number of targeted levels.

Artificial Intelligence-Driven Prediction Modeling and Decision Making in Spine Surgery Using Hybrid Machine Learning Models

Healthcare systems worldwide generate vast amounts of data from many different sources. Although of high complexity for a human being, it is essential to determine the patterns and minor variations in the genomic, radiological, laboratory, or clinical data that reliably differentiate phenotypes or allow high predictive accuracy in health-related tasks. Convolutional neural networks (CNN) are increasingly applied to image data for various tasks. Its use for non-imaging data becomes feasible through different modern machine learning techniques, converting non-imaging data into images before inputting them into the CNN model. Considering also that healthcare providers do not solely use one data modality for their decisions, this approach opens the door for multi-input/mixed data models which use a combination of patient information, such as genomic, radiological, and clinical data, to train a hybrid deep learning model. Thus, this reflects the main characteristic of artificial intelligence: simulating natural human behavior. The present review focuses on key advances in machine and deep learning, allowing for multi-perspective pattern recognition across the entire information set of patients in spine surgery. This is the first review of artificial intelligence focusing on hybrid models for deep learning applications in spine surgery, to the best of our knowledge. This is especially interesting as future tools are unlikely to use solely one data modality. The techniques discussed could become important in establishing a new approach to decision-making in spine surgery based on three fundamental pillars: (1) patient-specific, (2) artificial intelligence-driven, (3) integrating multimodal data. The findings reveal promising research that already took place to develop multi-input mixed-data hybrid decision-supporting models. Their implementation in spine surgery may hence be only a matter of time.

Prediction of Long-Term Recovery From Disability Using Hemoglobin-Based Models: Results From a Cohort of 1,392 Patients Undergoing Spine Surgery

Hemoglobin and its associated blood values are important laboratory biomarkers that mirror the strength of constitution of patients undergoing spine surgery. Along with the clinical determinants available during the preadmission visit, it is important to explore their potential for predicting clinical success from the patient's perspective in order to make the pre-admission visit more patient-centered. We analyzed data from 1,392 patients with spine deformity, disc disease, or spondylolisthesis enrolled between 2016 and 2019 in our institutional Spine Registry. Patient-reported outcome measure at 17 months after surgery was referred to the Oswestry disability index. High preoperative hemoglobin was found to be the strongest biochemical determinant of clinical success along with high red blood cells count, while low baseline disability, prolonged hospitalization, and long surgical times were associated with poor recovery. The neural network model of these predictors showed a fair diagnostic performance, having an area under the curve of 0.726 and a sensitivity of 86.79%. However, the specificity of the model was 15.15%, thus providing to be unreliable in forecasting poor patient-reported outcomes. In conclusion, preoperative hemoglobin may be one of the key biomarkers on which to build appropriate predictive models of long-term recovery after spine surgery, but it is necessary to include multidimensional variables in the models to increase the reliability at the patient's level.

Single-level TLIF Versus LLIF at L4-5: A Comparison of Patient-reported Outcomes and Recovery Ratios

INTRODUCTION

Both transforaminal lumbar interbody fusion (TLIF) and lateral lumbar interbody fusion (LLIF) are suitable for achievement of lumbar arthrodesis. Comparative studies have observed complications and outcomes without stratification by lumbar level. This study aims to assess patient-reported outcome measures (PROMs) and recovery in TLIF and LLIF at L4-5.

METHODS

Patients undergoing primary, elective, single-level, TLIF or LLIF procedures at L4-5 were grouped. Demographics, perioperative characteristics, and postoperative complication rates were collected. PROMs included Patient-Reported Outcome Measurement Information System Physical Function, visual analog scale (VAS) back and leg, Oswestry Disability Index, and 12-Item Short-Form Physical Component Summary, and Mental Component Summary and were collected at preoperative, 6-week, 12-week, 6-month, 1-year, and 2-year time points. Delta values and recovery ratios (RRs) were calculated for all PROMs at all time points. Demographics, perioperative characteristics, and postoperative complications were compared using chi-squared and Student t-test for categorical and continuous variables, respectively. Differences in mean PROMs, delta values, and RR at each time point were evaluated using unpaired Student's t-test.

RESULTS

Three hundred sixty TLIF and 46 LLIF patients were included. Most (54.3%) were men, mean age 56.3 years, and mean body mass index 30.8 kg/m2. Body mass index and insurance significantly differed (P ≤ 0.045, all). TLIF showed significantly greater mean operative time, length of stay, and postoperative narcotic consumption (P < 0.033, all) and greater postoperative nausea/vomiting (P = 0.004). No preoperative PROMs significantly differed. TLIF cohort had significantly greater VAS back at 6 months and VAS leg at 12 weeks and 6 months (P < 0.034, all). No mean delta PROMs or RRs significantly differed.

DISCUSSION

LLIF demonstrated significantly reduced length of stay, postoperative narcotic consumption, and postoperative nausea/vomiting and significantly improved VAS back at 6 months and VAS leg at 12 weeks and 6 months versus TLIF. Although 2-year PROMs and RRs did not significantly differ, our findings may suggest improved midterm follow-up pain scores for LLIF patients.

Time to return to work after elective lumbar spine surgery

OBJECTIVE

Time to return to work (RTW) after elective lumbar spine surgery is variable and dependent on many factors including patient, work-related, and surgical factors. The primary objective of this study was to describe the time and rate of RTW after elective lumbar spine surgery. Secondary objectives were to determine predictors of early RTW (< 90 days) and no RTW in this population.

METHODS

A retrospective analysis of prospectively collected data from the multicenter Canadian Spine Outcomes and Research Network (CSORN) surgical registry was performed to identify patients who were employed and underwent elective 1- or 2-level discectomy, laminectomy, and/or fusion procedures between January 2015 and December 2019. The percentage of patients who returned to work and the time to RTW postoperatively were calculated. Predictors of early RTW and not returning to work were determined using a multivariable Cox regression model and a multivariable logistic regression model, respectively.

RESULTS

Of the 1805 employed patients included in this analysis, 71% returned to work at a median of 61 days. The median RTW after a discectomy, laminectomy, or fusion procedure was 51, 46, and 90 days, respectively. Predictors of early RTW included male gender, higher education level (high school or above), higher preoperative Physical Component Summary score, working preoperatively, a nonfusion procedure, and surgery in a western Canadian province (p < 0.05). Patients who were working preoperatively were twice as likely to RTW within 90 days (HR 1.984, 95% CI 1.680-2.344, p < 0.001) than those who were employed but not working. Predictors of not returning to work included symptoms lasting more than 2 years, an increased number of comorbidities, an education level below high school, and an active workers' compensation claim (p < 0.05). There were fourfold odds of not returning to work for patients who had not been working preoperatively (OR 4.076, 95% CI 3.087-5.383, p < 0.001).

CONCLUSIONS

In the Canadian population, 71% of a preoperatively employed segment returned to work after 1- or 2-level lumbar spine surgery. Most patients who undergo a nonfusion procedure RTW after 6 to 8 weeks, whereas patients undergoing a fusion procedure RTW at 12 weeks. Working preoperatively significantly increased the likelihood of early RTW.

Impact of Time to Surgery for Workers' Compensation Patients Undergoing MIS TLIF: A Preliminary Analysis on Clinical Outcomes

OBJECTIVE

To conduct a preliminary analysis on the impact of time to surgery (TTS) and duration of symptoms (DOS) on clinical outcomes in workers' compensation patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

METHODS

WC patients undergoing primary, single-level MIS TLIF were identified. PROMs were administered at preoperative/6-week/12-week/6-month postoperative timepoints and included VAS back/VAS leg/ODI/SF-12 PCS/SF-12 MCS. Patients were grouped by TTS: <90 days, 90-179 days, ≥180 days. Demographics were compared by chi-squared; perioperative characteristics, mean PROMs, and postoperative improvement (ΔPROM) were compared using one way ANOVA. MCID achievement rates were compared using simple logistic regression. A secondary analysis was performed by grouping patients by DOS: <180 days, 180-364 days, ≥365 days. Mean PROMs, ΔPROMs, and MCID achievement were similarly compared between DOS groups using one way ANOVA and logistic regression.

RESULTS

193 patients included. Prevalence of HNP and initial appointment type were significantly associated with TTS(p<0.042, all)(Tables 1 and 2). No significant differences in mean PROMs or ΔPROMs were observed among TTS groups(Tables 3 and 4). MCID achievement was significantly lower for VAS back at 6-months in longest TTS group(Table 4). Mean PROMs were significantly different based on DOS for VAS leg at 6-weeks only(Table 5). MCID achievement was significantly lower for longest DOS group for VAS leg at 6-months only. ΔPROMs did not significantly differ among DOS groups(Table 6).

CONCLUSION

Neither TTS nor DOS significantly associated with MIS TLIF outcomes. WC patients may achieve similar clinical improvement even with longer symptom burden and substantial delays in operative treatment.