Anne F. Mannion’s research while affiliated with Schulthess Klinik, Zürich and other places

Introduction The reliability of patient-reported outcome measures is typically evaluated in patients with chronic or stable symptoms, pre-treatment. After treatment, symptoms may be less extreme and less variable within a group, which may influence indices of reliability. Further, few studies have examined the reliability of retrospective, single item global assessment scores after treatment, despite the latter often being used as the external criterion when determining an instrument’s minimal clinically important change (MCIC) score. This study examined the stability of Core Outcome Measures Index (COMI) and Global Treatment Outcome (GTO) scores after spine surgery. Methods Data were extracted for patients with lumbar spinal stenosis who had completed the COMI and GTO twice at follow-up, for both an in-house outcomes database (ROUTINE) and as part of a separate prospective study (LSOS). To be included, the questionnaires had to have been completed within 3 months of each other for 1-year follow-up (FU), within 4 months for 2-year FU and within 5 months for 5-year FU. Repeated measures ANOVA, intraclass correlation coefficients (ICC; 2-way mixed, absolute agreement), and weighted Kappa values were calculated. Results 64 patients (72.9 ± 6.9 y; 48% female) had a COMI and GTO available from both ROUTINE and LSOS, completed on average 9.8 ± 6.2 weeks apart. There were no significant differences between test and retest scores for any of the COMI domains or for the COMI summary score (all p > 0.05), and ICCs/weighted Kappas were moderate to good (0.73–0.87). In the ROUTINE and LSOS datasets, 83% and 81% patients, respectively, reported a “good global outcome” on the GTO (i.e. treatment helped/helped a lot); the corresponding Kappa for agreement between the ratings on an individual basis was 0.74 (“good agreement”). Conclusion Despite the more stringent nature of the evaluation given by this “real-life” analysis of the stability of outcome scores, the FU COMI scores showed moderate to good reliability comparable to that reported in previous studies with reliability assessed 1–2 weeks apart. The GTO was also confirmed as a reliable variable yielding stable values at mid to longer term follow-up.

Purpose Degenerative spondylolisthesis (DS) is addressed with a wide range of surgical techniques, though controversy exists regarding surgical technique selection. Given the lack of high-quality evidence to guide surgical technique selection in DS, appropriateness criteria and classification systems have been developed based on expert opinion. The DSIC System uses imaging and patient characteristics to predict stability. The purpose of this study was to evaluate the DSIC system as a guide for technique selection by determining if patients within each DSIC Type have different outcomes when treated with various surgical techniques. Methods Patients undergoing surgery for symptomatic DS were prospectively enrolled at two centers. All patients were classified by DSIC Type and surgical technique. Due to small numbers in some subgroups, decompression alone and decompression with uninstrumented fusion were combined as uninstrumented group and decompression with instrumented and circumferential fusion were combined as instrumented group. The primary outcome was the 12-month change on the Core Outcome Measures Index (COMI). Results Of the 508 patients enrolled, 459 patients could be classified according to DSIC criteria. 10 patients were classified as DSIC Type I (stable), 366 as DSIC Type II (potentially unstable), and 83 as DSIC Type III (unstable). Surgical technique varied significantly across DSIC Type, with decompression alone performed most commonly in DSIC I and decompression and fusion performed more commonly in DSIC II and III. There were no significant differences in COMI scores between the DSIC groups at baseline, 3 or 12 months post-operatively. At 12 months, the DSIC I uninstrumented group improved by 3.48 points on the COMI compared to 1.75 points in the DSIC I instrumented group (p > 0.05). The DSIC III uninstrumented group improved by 2.94 points at 12 months compared to the DSIC III instrumented group that improved by 4.06 points (p > 0.05). DSIC II patients showed similar COMI score improvement between the surgical technique groups. All DSIC groups improved significantly from baseline with greater than 75% of patients meeting minimal clinically important difference. Patients in DSIC I trended toward greater improvement with decompression alone, and patients in DSIC III trended toward greater improvement with decompression and instrumented fusion. There were no significant differences in reoperation rates between surgical technique cohorts. Conclusion This study found no significant differences in COMI scores between the surgical technique cohorts within each DSIC Type. There were non-significant trends suggesting that DSIC III patients with unstable slips may benefit from instrumented fusion, whereas DSIC I patients with stable slips may improve more with decompression alone or with an uninstrumented fusion. This study does not support the use of the DSIC for surgical technique selection and suggests that more work is needed to develop an evidence-based classification system that can guide surgical technique selection.

Purpose We aimed to validate and cross-culturally adapt the Core Outcome Measures Index (COMI) neck for use in Portuguese patients with cervical spine degenerative disease and define the minimal clinically important change score (MCIC) for this questionnaire and population. Methods The COMI translation and cross-cultural adaptation was done following published guidelines. Patients awaiting surgery in a neurosurgical centre completed the COMI, Neck Disability Index (NDI) and EQ-5D questionnaires, a pain visual analog scale (VAS) twice within a 5-to-15-day period, and a Global Treatment Outcome (GTO) question evaluating whether a clinical status change had occurred during that period. The MCIC was obtained through an anchor method by analysis of changes in pre- to postoperative total COMI scores and GTO dichotomized answers. Results The COMI first assessment was completed by 101 patients and 72 patients completed both assessments. The questionnaire showed good construct validity (n = 72 patients) as predefined hypotheses were confirmed: scores on each COMI domain correlated with a Spearman ρ > 0.4 with scores for the corresponding domain on other questionnaires and COMI total score displayed good correlation with total NDI score (ρ = 0.67) and EQ-5D total score (ρ = 0.55). Test-retest reliability (n = 72 patients) was confirmed through high intraclass correlation coefficients. The MCIC (n = 76 patients) was calculated as 2 points. Conclusion The COMI (neck) psychometric qualities were confirmed, such that it can be considered a valid and reliable questionnaire to be applied in the European Portuguese population with surgical cervical spine degenerative disease, with an MCIC of 2 points.

Introduction The Minimal Clinically Important Change (MCIC) is used in conjunction with Patient-Reported Outcome Measures (PROMs) to determine the clinical relevance of changes in health status. MCIC measures a change within the same person or group over time. This study aims to evaluate the variability in computing MCIC for the Core Outcome Measure Index (COMI) using different methods. Methods Data from a spine centre in Switzerland were used to evaluate variations in MCIC for the COMI score. Distribution-based and anchor-based methods (predictive and nonpredictive) were applied. Bayesian bootstrap estimated confidence intervals. Results From 27,003 cases, 9821 met the inclusion criteria. Distribution-based methods yielded MCIC values from 0.4 to 1.4. Anchor-based methods showed more variability, with MCIC values from 1.5 to 4.9. Predictive anchor-based methods also provided variable MCIC values for improvement (0.3–2.4), with high sensitivity and specificity. Discussion MCIC calculation methods produce varying values, emphasizing careful method selection. Distribution-based methods likely measure minimal detectable change, while non-predictive anchor-based methods can yield high MCIC values due to group averaging. Predictive anchor-based methods offer more stable and clinically relevant MCIC values for improvement but are affected by prevalence and reliability corrections.

Study design Heterogeneous data collection via a mix of prospective, retrospective, and ambispective methods. Objective To evaluate the effect of biological sex on patient-reported outcomes after spinal fusion surgery for lumbar degenerative disease. Summary of Background Data Current literature suggests sex differences regarding clinical outcome after spine surgery may exist. Substantial methodological heterogeneity and limited comparability of studies warrants further investigation of sex-related differences in treatment outcomes. Methods We analyzed patients who underwent spinal fusion with or without pedicle screw insertion for lumbar degenerative disease included within a multinational study, comprising patients from 11 centers in 7 countries. Absolute values and change scores (change from pe-operative baseline to post-operative follow-up) for 12-month functional impairment (Oswestry disability index [ODI]) and back and leg pain severity (numeric rating scale [NRS]) were compared between male and female patients. Minimum clinically important difference (MCID) was defined as > 30% improvement. Results Six-hundred-sixty (59%) of 1115 included patients were female. Female patients presented with significantly baseline ODI (51.5 ± 17.2 vs. 47.8 ± 17.9, P <0.001) and back pain (6.96 ± 2.32 vs. 6.60 ± 2.30, P =0.010) and leg pain (6.49 ± 2.76 vs. 6.01 ± 2.76, P =0.005). At 12-months, female patients still reported significantly higher ODI (22.76 ± 16.97 vs. 20.50 ± 16.10, P =0.025), but not higher back (3.13 ± 2.38 vs. 3.00 ± 2.40, P =0.355) or leg pain (2.62 ± 2.55 vs. .34 ± 2.43, P =0.060). Change scores at 12 months did not differ significantly among male and female patients in ODI (∆ 1.31, 95% CI -3.88-1.25, P =0.315), back (∆ 0.22, 95% CI -0.57-0.12, P =0.197) and leg pain (∆ 0.16, 95% CI -0.56-0.24, P =0.439). MCID at 12-months was achieved in 330 (77.5%) male patients and 481 (76.3%) female patients ( P =0.729) for ODI. Conclusion Both sexes experienced a similar benefit from surgery in terms of relative improvement in scores for functional impairment and pain. Although female patients reported a higher degree of functional impairment and pain preoperatively, at 12 months only their average scores for functional impairment remained higher than those for their male counterparts, while absolute pain scores were similar for female and male patients.

Introduction Epimuscular fat (EF) has rarely been studied in the context of low back pain (LBP). Research question This study aims to assess the presence and extent of EF in the lumbar muscles and its association with vertebral level in patients with low back disorders and to explore correlations between EF, demographics, BMI, and LBP. Material and methods T2 axial MRIs from L1 to L5 were manually segmented to analyze the cross-sectional area (CSA) of EF (mm²), and fat infiltration (FI,%) of 40 patients (23 females, 17 males; mean age:65.9 years) with lumbar degenerative pathologies awaiting a surgical procedure. COMI, LBP, demographic, and clinical data were extracted from the institutional registry. Statistical analyses included Wilcoxon and Mann-Whitney tests for differences in EF between sides and sexes, the Friedman test for EF size differences among lumbar levels, and Spearman’s correlation for associations, adjusted for BMI, age, and sex. Results EF was found in 77.5% of subjects at L1, 92.5% at L2, 100% at L3 and L4, and 95.0% at L5. EF was significantly larger at L4 (253.1 ± 183.6 mm²) and L5 (220.2 ± 194.9 mm²) than at L1 (36.1 ± 37.8 mm²) and L2 (72.2 ± 84.4 mm²). No significant EF differences were found between sides and sexes. EF correlated strongly with BMI (rs = 0.65,p < 0.001) and moderately with FI (rs = 0.31,p = 0.04), though its correlation with FI was not significant after adjustment. EF did not correlate with COMI scores but correlated with LBP in the adjusted analysis (rs:0.31,p = 0.04). Discussion and conclusion EF is present across all lumbar levels, with higher concentrations at L4 and L5, and a significant correlation between EF and LBP intensity was observed. The present findings are limited to a specific subset of patients with lumbar degenerative disorders who are awaiting surgical procedures.

Purpose This study aimed to develop machine learning methods to estimate bone mineral density and detect osteopenia/osteoporosis from conventional lumbar MRI (T1-weighted and T2-weighted images) and planar radiography in combination with clinical data and imaging parameters of the acquisition protocol. Methods A database of 429 patients subjected to lumbar MRI, radiographs and dual-energy x-ray absorptiometry within 6 months was created from an institutional database. Several machine learning models were trained and tested (373 patients for training, 86 for testing) with the following objectives: (1) direct estimation of the vertebral bone mineral density; (2) classification of T-score lower than − 1 or (3) lower than − 2.5. The models took as inputs either the images or radiomics features derived from them, alone or in combination with metadata (age, sex, body size, vertebral level, parameters of the imaging protocol). Results The best-performing models achieved mean absolute errors of 0.15–0.16 g/cm² for the direct estimation of bone mineral density, and areas under the receiver operating characteristic curve of 0.82 (MRIs) − 0.80 (radiographs) for the classification of T-scores lower than − 1, and 0.80 (MRIs) − 0.65 (radiographs) for T-scores lower than − 2.5. Conclusions The models showed good discriminative performances in detecting cases of low bone mineral density, and more limited capabilities for the direct estimation of its value. Being based on routine imaging and readily available data, such models are promising tools to retrospectively analyse existing datasets as well as for the opportunistic investigation of bone disorders.

Introduction Low-grade isthmic and degenerative spondylolisthesis (DS) of the lumbar spine are distinct pathologies but both can be treated with lumbar decompression with fusion. In a very large cohort, we compared patient-reported outcome in relation to the pathology and chief complaint at baseline. Methods This was a retrospective analysis using the EUROSPINE Spine Tango Registry. We included 582 patients (age 60 ± 15 years; 65% female), divided into four groups based on two variables: type of spondylolisthesis and chief pain complaint (leg pain (LP) versus back pain). Patients completed the COMI preoperatively and up to 5 years follow-up (FU), and rated global treatment outcome (GTO). Regression models were used to predict COMI-scores at FU. Pain scores and satisfaction ratings were analysed. Results All patients experienced pronounced reductions in COMI scores. Relative to the other groups, the DS-LP group showed between 5% and 11% greater COMI score reduction (p < 0.01 up to 2 years’ FU). This group also performed best with respect to pain outcomes and satisfaction. Long-term GTO was 93% at the 5 year FU, compared with between 82% and 86% in the other groups. Conclusion Regardless of the type of spondylolisthesis, all groups experienced an improvement in COMI score after surgery. Patients with DS and LP as their chief complaint appear to benefit more than other patients. These results are the first to show that the type of the spondylolisthesis and its chief complaint have an impact on surgical outcome. They will be informative for the consent process prior to surgery and can be used to build predictive models for individual outcome.

Study Design Single centre retrospective study of prospectively collected data. Objective Analyse factors associated with patient reported outcome after far lateral decompression surgery (FLDS) for lumbar nerve root compression using the far-lateral approach. Summary of Background Data To date, no studies have investigated the influence of vertebral level, coronal segmental Cobb angle, and the nature of the compressive tissue (hard/soft) on patient reported outcome following FLDS. Methods Patients who had undergone FLDS between 2005 and 2020 were included. Coronal segmental angle (CSCA) was measured on preoperative, posteroanterior radiographs. Primary outcome measure was the Core Outcome Measures Index (COMI) score at 2 years’ follow-up (2Y-FU). Patients who had undergone microsurgical decompression using a midline approach (MID) served as a comparator group. Results There were 148 FLDS and 463 MID patients. In both groups there was a significant improvement in COMI score from preoperative to 2Y-FU ( P <0.0001), with greater improvement in patients treated at higher vertebral levels than in those treated at L5/S1 ( P =0.014). Baseline COMI, ASA grade, BMI, and low back pain as the “chief complaint” all had a significant association with the 2-year COMI score. The nature of compressive tissue showed no association with COMI score at 2Y-FU. In the FLDS group, there was a statistically significant correlation between the preoperative CSCA and change in COMI score preoperatively to 2Y-FU ( P <0.001). The association was retained in multiple regression analysis controlling for confounders. A one-degree increase in CSCA was associated with a 0.35-point worse COMI score at 2Y-FU ( P =0.003). Conclusion Treatment of far lateral nerve root compression showed overall good patient reported outcome, but with less improvement with advanced coronal segmental angulation. Modified approaches and techniques might be preferable for the level L5/S1.

Background Clinical prediction models (CPM), such as the SCOAP-CERTAIN tool, can be utilized to enhance decision-making for lumbar spinal fusion surgery by providing quantitative estimates of outcomes, aiding surgeons in assessing potential benefits and risks for each individual patient. External validation is crucial in CPM to assess generalizability beyond the initial dataset. This ensures performance in diverse populations, reliability and real-world applicability of the results. Therefore, we externally validated the tool for predictability of improvement in oswestry disability index (ODI), back and leg pain (BP, LP). Methods Prospective and retrospective data from multicenter registry was obtained. As outcome measure minimum clinically important change was chosen for ODI with ≥ 15-point and ≥ 2-point reduction for numeric rating scales (NRS) for BP and LP 12 months after lumbar fusion for degenerative disease. We externally validate this tool by calculating discrimination and calibration metrics such as intercept, slope, Brier Score, expected/observed ratio, Hosmer–Lemeshow (HL), AUC, sensitivity and specificity. Results We included 1115 patients, average age 60.8 ± 12.5 years. For 12-month ODI, area-under-the-curve (AUC) was 0.70, the calibration intercept and slope were 1.01 and 0.84, respectively. For NRS BP, AUC was 0.72, with calibration intercept of 0.97 and slope of 0.87. For NRS LP, AUC was 0.70, with calibration intercept of 0.04 and slope of 0.72. Sensitivity ranged from 0.63 to 0.96, while specificity ranged from 0.15 to 0.68. Lack of fit was found for all three models based on HL testing. Conclusions Utilizing data from a multinational registry, we externally validate the SCOAP-CERTAIN prediction tool. The model demonstrated fair discrimination and calibration of predicted probabilities, necessitating caution in applying it in clinical practice. We suggest that future CPMs focus on predicting longer-term prognosis for this patient population, emphasizing the significance of robust calibration and thorough reporting.