Prevalence and Factors Associated with High Impact Chronic Pain in Knee Osteoarthritis: the Johnston County Health Study.

Pain is a hallmark symptom of knee osteoarthritis (KOA) yet intensity and severity vary widely among individuals. There is a knowledge gap in understanding key characteristics of high impact chronic pain (HICP) within the context of KOA. Therefore, our first purpose was to examine the prevalence of HICP in a cohort of individuals with radiographic evidence of KOA, and our second purpose was to assess patient level factors associated with HICP. Data from the Johnston County Health Study (JoCoHS) were used to compare those with and without HICP. Variables included sociodemographic factors, clinical factors, health care use, and psychosocial distress. HICP status was classified with PROMIS Pain Interference (PI) and Physical Function (PF) measures. Results indicated that 15.5% (48/310) of participants were classified as having HICP when the PROMIS-PI cutoff score was used, while 21.2% (66/310) were classified as having HICP with a PROMIS-PF cutoff score. Multivariable analyses indicated that HICP was consistently characterized by increased kinesiophobia and somatization regardless of PROMIS measure used for HICP status. A secondary insight was that HICP was not consistently characterized by sociodemographic and clinical variables, as these findings were dependent on PROMIS measured used. These findings could be used to develop intervention approaches specific to individuals with KOA and to inform future investigations of sociodemographic and clinical factors associated with HICP. PERSPECTIVE: These findings provide additional information on the characterization of HICP for individuals with KOA. There was consistency in psychosocial factors associated with HICP, while sociodemographic and clinical factors varied based on how HICP status was defined.

Characterizing Acute Low Back Pain in a Community-Based Cohort: Results from a Feasibility Cohort Study.

Introduction: Acute low back pain (LBP) is a common experience; however, the associated pain severity, pain frequency, and characteristics of individuals with acute LBP in community settings have yet to be well understood. In this manuscript, two acute-LBP severity categorization definitions were developed: 1) pain impact frequency (impact-based) and 2) pain intensity (intensity-based) severity categories. The purpose of this manuscript is to describe and then compare these acute-LBP severity groups in the following characteristics: 1) sociodemographic, 2) general and physical health, and 3) psychological using a feasibility cohort study. Methods: This cross-sectional study used baseline data from 131 community-based participants with acute LBP (<4 weeks duration before screening and ≥30 pain-free days before acute LBP onset). Descriptive associations were calculated as prevalence ratios of categorical variables and Hedges' g for continuous variables. Results: Our analyses identified several large associations for impact-based and intensity-based categories with global mental health, global physical health, STarT Back Screening Tool risk category, and general health. Larger associations were found with social constructs (racially and ethnically minoritized, performance of social roles, and isolation) when using the intensity-based versus impact-based categorization. Discussion: This study adds to the literature by providing standard ways to characterize community-based individuals experiencing acute-LBP. The robust differences observed between these categorization approaches suggest that how we define acute-LBP severity is consequential; these different approaches may be used to improve the early identification of factors potentially contributing to the development of chronic-LBP.

Cost-effectiveness of Risk Stratified Care vs Usual Care for Low Back Pain in the Military Health System.

STUDY DESIGN: Cost-effectiveness of two trial interventions for low back pain. OBJECTIVE: To investigate the incremental cost-effectiveness between risk-stratified and usual care for low back pain. SUMMARY OF BACKGROUND DATA: A recent trial compared risk-stratified care to usual care for patients with low back pain (LBP) in the US Military Health System. While the outcomes were no different between groups, risk-stratified care is purported to use fewer resources and therefore could be a more cost-effective intervention. Risk-stratified care matches treatment based on low, medium, or high risk for poor prognosis. METHODS: The cost-effectiveness of usual care versus risk-stratified care for low back pain was assessed, using the healthcare perspective. Patients were recruited from primary care. The main outcome was indicating incremental cost-effectiveness between two alternative treatments. Acceptability curves of bootstrapped incremental cost effectiveness ratios (ICER) were used to identify the proportion of ICERs under the specific willingness-to-pay (WTP) level ($50,000 to $100,000). Health system costs (total and back-related) and health-related quality-of-life (HRQoL) based on quality-adjusted-life-years (QALYs) were obtained. RESULTS: 271 participants (33.6% female), mean age 34.3 +/-8.7 were randomized 1:1 and followed for 1 year. Mean back-related medical costs were not significantly different (mean difference $5; 95CI -$398, $407; P=0.982), nor were total medical costs (mean difference $827, 95CI -$1748, $3403; P=0.529). The mean difference in QALYs was not significantly different between groups (0.009; 95CI -0.014, 0.032; P=0.459). The incremental net monetary benefit (NMB) at the willingness to pay (WTP) threshold of $100,000 was $792 for back-related costs, with the lower bound confidence interval negative at all WTP levels. CONCLUSION: Risk-stratified care was not cost-effective for medium- and low-risk individuals compared to usual care. Further research is needed to assess whether there is value for high-risk individuals or for other risk-stratification approaches.

Personal characteristic differences among Doctor of Physical Therapy students with unique sociodemographic factors.

BACKGROUND: The Association of American Medical Colleges suggests an Experiences-Attributes-Metrics framework for holistic review, but there is minimal research on demographic and personal characteristic attributes and the interplay between these Attributes subcategories. Understanding how personal attributes may vary among students considered represented and those considered underrepresented in one or more categories is critical to avoid unintentionally perpetuating practices that favor represented groups. This study explored differences in six personal characteristics either consistently related to academic performance or deemed positive professional traits based on diversity characteristics (categories of underrepresentation), age, and sex. METHODS: Three cohorts of first-year Doctor of Physical Therapy students at a single institution were invited to participate in this prospective, observational study. Participants completed six surveys: PROMIS® General Self-efficacy, PROMIS® Anxiety, 12-item Grit Scale, Perceived Stress Scale-10 (PSS-10), Brief Resilience Scale (BRS), and PROMIS® Positive Affect. T-tests and ANOVAs (or nonparametric equivalents) were used to examine differences in these measures by number of diversity characteristics, age, and sex. Multivariate linear regression was used to determine if diversity characteristics explained additional variance in each of the personal attribute scores after controlling for age and sex. RESULTS: One Hundred and Forty Five students participated (80.7% female, 77.9% < 25 years old, 51% 0 diversity characteristics). Students with more diversity characteristics and males reported higher self-efficacy and resilience (p's < 0.05). Females reported higher anxiety (p's < 0.01). Diversity characteristics explained additional variance in self-efficacy (3.3%, p = 0.02) and resilience (2.5%, p = 0.05) after controlling for age and sex. Grit, perceived stress, and positive affect did not show any group differences. CONCLUSIONS: Underrepresented students demonstrated higher self-efficacy and resilience than their represented peers, qualities that may be important to overcome challenges prior to and during graduate school. Males exhibited higher self-efficacy and resilience, but lower anxiety than females which is generally consistent across higher education. Grit, perceived stress, and positive affect were similar across all students and may be less useful to create a diverse learning environment. Further studies should investigate differences in attributes among admitted and unadmitted students and the relationship to future performance for admitted students.

Measurement Properties of Two Questionnaires Assessing Fear-Avoidance in Patients With Chronic Low Back Pain.

The Fear-Avoidance Components Scale (FACS) and the Fear of Daily Activities Questionnaire (FDAQ) assess fear-avoidance model components. However, the questionnaires are not available in Brazilian Portuguese. This study aimed to translate the original English FACS and FDAQ into Brazilian (Br) Portuguese and assess their measurement properties in patients with Chronic Low Back Pain (CLBP). One hundred thirty volunteers with CLBP participated in this study. Structural validity, internal consistency, test-retest reliability, and hypothesis testing for construct validity were analyzed. Results indicated a 2-factor solution for the FACS-Br, while the FDAQ-Br had a one-factor solution. Internal consistency showed acceptable Cronbach's alpha (alpha >.8). Suitable reliability was found for the FDAQ-Br (Intraclass Correlation Coefficient [ICC] = .98). For both FACS-Br factors, suitable reliability was found as well (ICC = .95 and .94). Hypothesis testing for construct validity confirmed more than 75% of the hypotheses proposed a priori for the FACS maladaptive pain/movement-related beliefs domain and the FDAQ-Br. In conclusion, the FACS-Br and FDAQ-Br demonstrated acceptable reliability, internal consistency, and structural validity measurement properties and their correlation (r < .50) suggests that the tools are not interchangeable measures.

Telehealth delivery of physical therapist-led interventions for persons with chronic low back pain in underserved communities: lessons from pragmatic clinical trials.

In this perspective, we present our experience developing and conducting two pragmatic clinical trials investigating physical therapist-led telehealth strategies for persons with chronic low back pain. Both trials, the BeatPain Utah and AIM-Back trials, are part of pragmatic clinical trial collaboratories and are being conducted with persons from communities that experience pain management disparities. Practice guidelines recommend nonpharmacologic care, and advise against opioid therapy, for the primary care management of persons with chronic low back pain. Gaps between these recommendations and actual practice patterns are pervasive, particularly for persons from racial or ethnic minoritized communities, those with fewer economic resources, and those living in rural areas including Veterans. Access barriers to evidence-based nonpharmacologic care, which is often provided by physical therapists, have contributed to these evidence-practice gaps. Telehealth delivery has created new opportunities to overcome access barriers for nonpharmacologic pain care. As a relatively new delivery mode however, telehealth delivery of physical therapy comes with additional challenges related to technology, intervention adaptations and cultural competence. The purpose of this article is to describe the challenges encountered when implementing telehealth physical therapy programs for persons with chronic low back pain in historically underserved communities. We also discuss strategies developed to overcome barriers in an effort to improve access to telehealth physical therapy and reduce pain management disparities. Inclusion of diverse and under-represented communities in pragmatic clinical trials is a critical consideration for improving disparities, but the unique circumstances present in these communities must be considered when developing implementation strategies.

Developing a Computer Vision Model to Automate Quantitative Measurement of Hip-Knee-Ankle Angle in Total Hip and Knee Arthroplasty Patients.

BACKGROUND: Increasing deformity of the lower extremities, as measured by the hip-knee-ankle angle (HKAA), is associated with poor patient outcomes after total hip and knee arthroplasty (THA, TKA). Automated calculation of HKAA is imperative to reduce the burden on orthopaedic surgeons. We proposed a detection-based deep learning (DL) model to calculate HKAA in THA and TKA patients and assessed the agreement between DL-derived HKAAs and manual measurement. METHODS: We retrospectively identified 1,379 long-leg radiographs (LLRs) from patients scheduled for THA or TKA within an academic medical center. There were 1,221 LLRs used to develop the model (randomly split into 70% training, 20% validation, and 10% held-out test sets); 158 LLRs were considered "difficult," as the femoral head was difficult to distinguish from surrounding tissue. There were 2 raters who annotated the HKAA of both lower extremities, and inter-rater reliability was calculated to compare the DL-derived HKAAs with manual measurement within the test set. RESULTS: The DL model achieved a mean average precision of 0.985 on the test set. The average HKAA of the operative leg was 173.05 ± 4.54°; the nonoperative leg was 175.55 ± 3.56°. The inter-rater reliability between manual and DL-derived HKAA measurements on the operative leg and nonoperative leg indicated excellent reliability (intraclass correlation (2,k) = 0.987 [0.96, 0.99], intraclass correlation (2, k) = 0.987 [0.98, 0.99, respectively]). The standard error of measurement for the DL-derived HKAA for the operative and nonoperative legs was 0.515° and 0.403°, respectively. CONCLUSIONS: A detection-based DL algorithm can calculate the HKAA in LLRs and is comparable to that calculated by manual measurement. The algorithm can detect the bilateral femoral head, knee, and ankle joints with high precision, even in patients where the femoral head is difficult to visualize.

Transition from Acute to Chronic Low Back Pain in a Community-Based Cohort.

The transition from acute to chronic low back pain (LBP) in community settings has yet to be well understood. We recruited n=131 participants with acute LBP from the community and followed them for 3 and 6-month outcomes. Acute LBP was defined by a duration of < 4 weeks, and participants must have reported a 30-day LBP-free period before the current acute episode. Chronic LBP was defined as pain most or every day over the past 3 months. Baseline psychological, social, and demographic factors were examined as predictors of transition to chronic LBP at 3 months or continuation of chronic LBP at 6 months. The transition from acute to chronic LBP at 3 months was 32.2% ( 38/118). At 6 months, 80.7% (25/111) of participants who transitioned at 3 months continued to have chronic LBP. At 6 months, participants who identified as Black or African American were more likely than white participants to transition to chronic LBP (RR=1.76, 95% CI 1.05, 2.95) and more likely to continue to have chronic LBP (RR=2.19, 95% CI 1.14, 4.21). Those classified at baseline by both LBP most or every day and intensity of at least 30/100 were more likely to transition to chronic LBP (RR=3.13, 95% CI 1.84, 5.30) and continue to have chronic LBP at 6 months (RR=2.58, 95% CI 1.43, 4.16). The STarT Back Screening Tool and the OSPRO-YF were associated with the transition to chronic LBP at 3 months and continuation at 6 months. Participants with higher PROMIS General Health and PROMIS Physical Health scores were less likely to transition to chronic LBP or continue to have chronic LBP at 6 months. These findings identify factors of acute LBP in the community that may predict the transition to chronic LBP. Larger studies are needed to confirm these findings and better understand the mechanisms driving the transition to chronic LBP.

Clinimetric Properties of the Working Alliance Inventory and Credibility Expectancy Questionnaire: Screening Options for Musculoskeletal Pain.

OBJECTIVE: To investigate clinimetric properties of 2 surveys used to evaluate common factors in the patient-provider relation and present screener options for the assessment of common factors and report their correlation with pain and functional outcomes. DESIGN: Observational cohort. SETTING: Outpatient physical therapy. PARTICIPANTS: 100 individuals (58% women, mean age=34, SD=15; N=100) presenting to physical therapy with musculoskeletal pain in the following regions: 44% lower extremity, 36% spine, 19% upper extremity, 1% undetermined. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Participants completed the Working Alliance Inventory (WAI) and the Credibility and Expectancy Questionnaire (CEQ). Exploratory factor analysis (EFA) explored factor structure of the WAI and CEQ. Internal consistency was evaluated for scales derived from items retained based on factor loadings. Finally, options for screener tools were proposed and assessed based on their correlation to original surveys as well as pain and functional outcomes. RESULTS: The data supported a 4-factor structure for the surveys. Some WAI items were excluded due to cross-loading. The derived four-factor scales demonstrated strong correlations with the original surveys (r=.89-.99) and exhibited good internal consistency (α=.824-.875). Two screening options were suggested: 1 retaining 11 of the original 18 items and the other comprising just 3 items. Both screening tools correlated with the original surveys and showed associations with improvements in pain and functional outcomes (r=-.21-.34). CONCLUSION: The proposed screeners provide concise measurement options to facilitate use in clinical practice. These tools can aid in facilitating patient communication specifically addressing patient expectation and understanding the tasks required to enact behavior change.

Utility of Patient Reported Outcome Measurement Information System measures in predicting shoulder arthroplasty in patients with shoulder osteoarthritis.

BACKGROUND: The decision to treat shoulder osteoarthritis (OA) definitively with shoulder arthroplasty (SA) is multifactorial, considering objective findings, subjective information, and patient goals. The first goal of this study was to determine if Patient Reported Outcome Measurement Information System (PROMIS) measures correlated with patients with shoulder OA who underwent SA within 1 year. The second goal of this study was to determine if score cut-offs in PROMIS domains could further discriminate which shoulder OA patients underwent SA within 1 year. METHODS: This retrospective case-control study examined patients with a diagnosis of shoulder OA who consulted an orthopedic provider from November 1, 2020 to May 23, 2022, and recorded PROMIS measures in the domains of Physical Function, Depression, and/or Pain Interference. A surgical group was defined as patients who underwent SA within 1 year of the most recent PROMIS measures and the nonsurgical patients were defined as the control group. Mean PROMIS scores were compared between the surgical and control groups. Separate logistic regression models controlling for age, race, ethnicity, and comorbidity count were performed for each PROMIS domain as a 1) continuous variable, and then as 2) binary variable defined by PROMIS score cut-off points to determine which scores correlated with undergoing SA to further characterize the potential clinical utility of PROMIS score cut-offs in relating to undergoing SA. RESULTS: The surgical group of 478 patients was older (68.2 vs. 63.8 years), more often of White race (82.6% vs. 70.9%), and less often of Hispanic Ethnicity (1.5% vs. 2.9%) than the control group of 3343 patients. Using optimal cut-offs in PROMIS scores, Pain Interference ≥63 (odds ratio [OR] = 2.97 (2.41-3.64), P < .001), Physical Function ≤39 (OR = 1.81 (95% confidence interval, 1.48-2.22), P < .001), and depression ≥49 (OR = 1.82 (95% confidence interval, 1.50-2.22), P < .001) were all found to correlate with undergoing SA within 1 year in multivariable logistic regressions. CONCLUSION: The results of this study demonstrate that cut-off scores for PROMIS measures differentiated patients undergoing SA within 1 year. These cut-off scores may have clinical utility in aiding in decision-making regarding surgical candidates for SA. Further research is needed to validate these cut-off scores and determine how they relate to patient outcomes after SA.

General and Pain-Associated Psychological Distress Phenotypes Among Patients With Low Back Pain in the Military Health System.

OBJECTIVE: The primary objective was to describe rates of general and pain-related psychological distress for individuals with low back pain (LBP) in the Military Health System (MHS). We identified common phenotypes defined by rates of general and pain-related psychological distress and compared phenotypes on their level of pain interference, physical function, anxiety, and depression. METHODS: We created a cohort from two completed trials assessing nonpharmacological treatment for LBP in the MHS (n = 510 total). The Optimal Screening for Prediction of Referral and Outcome Yellow Flag assessment tool identified the presence of 11 different yellow flags. Latent class analysis (LCA) used yellow flag indicators to identify common psychological phenotypes. We then compared Patient-Reported Outcomes Measurement Information Systems measures of pain interference, physical function, sleep disturbance, depression, and anxiety across phenotypes. RESULTS: LCA identified five phenotypes (percentage of the sample): low distress (32%), high distress (27%), poor pain coping and low self-efficacy (18%), low self-efficacy and acceptance (14%), and poor pain coping (10%). Highly distressed phenotypes reported higher levels of pain interference, sleep disturbance, depression, and anxiety than those with other phenotypes, whereas the low distress phenotype had significantly lower pain interference and higher physical function scores than those characterized by all other phenotypes. CONCLUSION: These phenotypes provide opportunities for clinicians and researchers to develop novel LBP treatment pathways tailored to patients with different profiles of psychological distress. Future work is needed to validate their predictive capabilities for clinical outcomes.

Acute Intermittent Hypoxia Did Not Alter Pain Sensitivity or Pain Intensity Ratings for Individuals with Chronic Low Back Pain: A Pilot Study.

Aims and Objective: The purpose of this pilot study was to explore whether AIH produces changes in pain sensitivity or in reports of self-reported pain intensity for individuals with low back pain. Methods: In a quasi-experimental, cross-over design we compared participants (n = 9) exposed to normal room air and hypoxia using a commercially available gas blender. The treatment period consisted of 5 consecutive days of randomly assigned to AIH or room air. For the participants initially randomized to AIH there was cross-over to receive 5 more consecutive days of room air. Therefore, this design allowed for between group and within subject assessment of AIH effects. Pain sensitivity was assessed with quantitative sensory testing (QST) for posterior superior iliac spine pressure threshold, plantar thermal threshold, and peak pain ratings. Self-reported pain intensity for low back pain was assessed via the Brief Pain Inventory. Results: There were no between group differences for AIH and room air in pain sensitivity or self-reported pain intensity. In the within subject analyses larger effect sizes favoring AIH were detected for plantar measures of pain sensitivity but not for self-reported pain intensity. Conclusion: This study, while presenting null findings, describes an initial step in determining whether AIH can be used to increase pain relief. Based on this pilot study we offer guidance for future research including study design, AIH dosage, participant selection, and using AIH in combination with non-pharmacologic treatments.

Nociceptive, neuropathic, or nociplastic low back pain? The low back pain phenotyping (BACPAP) consortium's international and multidisciplinary consensus recommendations.

The potential to classify low back pain as being characterised by dominant nociceptive, neuropathic, or nociplastic mechanisms is a clinically relevant issue. Preliminary evidence suggests that these low back pain phenotypes might respond differently to treatments; however, more research must be done before making specific recommendations. Accordingly, the low back pain phenotyping (BACPAP) consortium was established as a group of 36 clinicians and researchers from 13 countries (five continents) and 29 institutions, to apply a modified Nominal Group Technique methodology to develop international and multidisciplinary consensus recommendations to provide guidance for identifying the dominant pain phenotype in patients with low back pain, and potentially adapt pain management strategies. The BACPAP consortium's recommendations are also intended to provide direction for future clinical research by building on the established clinical criteria for neuropathic and nociplastic pain. The BACPAP consortium's consensus recommendations are a necessary early step in the process to determine if personalised pain medicine based on pain phenotypes is feasible for low back pain management. Therefore, these recommendations are not ready to be implemented in clinical practice until additional evidence is generated that is specific to these low back pain phenotypes.

Hip-focused physical therapy versus spine-focused physical therapy for older adults with chronic low back pain at risk for mobility decline (MASH): a multicentre, single-masked, randomised controlled trial.

BACKGROUND: Previously, we identified a population of older adults with chronic low back pain, hip pain, and hip muscle weakness who had worse 12-month low back pain and functional outcomes than age-matched adults with only low back pain, indicating an increased risk for future mobility decline. We sought to determine whether tailored, hip-focused physical therapy reduced pain and functional limitations in this high-risk population compared with non-tailored, spine-focused physical therapy. METHODS: We did a multicentre, single-masked, randomised controlled trial at three research-based sites in the USA. We recruited older adults (aged 60-85 years) with hip pain and weakness who reported moderate low back pain intensity at least half the days in the last 6 months. Patients were randomly assigned to hip-focused physical therapy or spine-focused physical therapy using permuted blocks with random block size, stratified by site and sex (ie, male or female). The primary outcomes were self-reported disability using the Quebec Back Pain Disability Scale (QBPDS) and performance-based 10-Meter Walk Test (10MWT) at 8 weeks. All analyses were done in the intention-to-treat population. Adverse events were collected by study staff via a possible adverse event reporting form and then adjudicated by site investigators. This trial was registered with ClinicalTrials.gov, NCT04009837. FINDINGS: Between Nov 1, 2019, and April 30, 2022, 184 participants were randomly assigned to receive hip-focused (n=91) or spine-focused physical therapy (n=93) interventions. The mean age was 70·7 (SD 6·2) years. 121 (66%) of 184 participants were women, 63 (34%) were men, and 149 (81%) were White. At 8 weeks, the mean between-group difference on the QBPDS was 4·0 (95% CI 0·5 to 7·5), favouring hip-focused physical therapy. Both groups had similar, clinically meaningful gait speed improvements (10MWT) at 8 weeks (mean difference 0·004 m/s [95% CI -0·044 to 0·052]). No serious adverse events were related to study participation. INTERPRETATION: Tailored hip-focused physical therapy demonstrated greater improvements in low back pain-related disability at 8 weeks. However, both hip-focused physical therapy and spine-focused physical therapy produced clinically meaningful improvements in disability and function for this high-risk population at 6 months. These findings warrant further investigation before clinical implementation. FUNDING: US National Institute on Aging of the National Institutes of Health.