Lower Extremity Osteoarthritis Research Articles

Disease-modifying rdHSV-CA8* non-opioid analgesic gene therapy treats chronic osteoarthritis pain by activating Kv7 voltage-gated potassium channels.

Chronic pain is common in our population, and most of these patients are inadequately treated, making the development of safer analgesics a high priority. Knee osteoarthritis (OA) is a primary cause of chronic pain and disability worldwide, and lower extremity OA is a major contributor to loss of quality-adjusted life-years. In this study we tested the hypothesis that a novel JDNI8 replication-defective herpes simplex-1 viral vector (rdHSV) incorporating a modified carbonic anhydrase-8 transgene (CA8*) produces analgesia and treats monoiodoacetate-induced (MIA) chronic knee pain due to OA. We observed transduction of lumbar DRG sensory neurons with these viral constructs (vHCA8*) (~40% of advillin-positive cells and ~ 50% of TrkA-positive cells colocalized with V5-positive cells) using the intra-articular (IA) knee joint (KJ) route of administration. vHCA8* inhibited chronic mechanical OA knee pain induced by MIA was dose- and time-dependent. Mechanical thresholds returned to Baseline by D17 after IA KJ vHCA8* treatment, and exceeded Baseline (analgesia) through D65, whereas negative controls failed to reach Baseline responses. Weight-bearing and automated voluntary wheel running were improved by vHCA8*, but not negative controls. Kv7 voltage-gated potassium channel-specific inhibitor XE-991 reversed vHCA8*-induced analgesia. Using IHC, IA KJ of vHCA8* activated DRG Kv7 channels via dephosphorylation, but negative controls failed to impact Kv7 channels. XE-991 stimulated Kv7.2-7.5 and Kv7.3 phosphorylation using western blotting of differentiated SH-SY5Y cells, which was inhibited by vHCA8* but not by negative controls. The observed prolonged dose-dependent therapeutic effects of IA KJ administration of vHCA8* on MIA-induced chronic KJ pain due to OA is consistent with the specific activation of Kv7 channels in small DRG sensory neurons. Together, these data demonstrate for the first-time local IA KJ administration of vHCA8* produces opioid-independent analgesia in this MIA-induced OA chronic pain model, supporting further therapeutic development.

Comparative Evaluation of the Effectiveness of Adductor Canal Block versus Conservative Treatment for the Management of Anteromedial Knee Pain in Knee Osteoarthritis: A Prospective Study

Abstract Context: Knee osteoarthritis (KOA) is the most common type of lower extremity osteoarthritis (OA), with pain being the predominant symptom, leading to significant morbidity and impaired quality of life. Objectives: This study was designed to ascertain the effectiveness of ultrasound-guided adductor canal block (ACB), ensuing functional improvement and change in the quality of life in KOA patients with anteromedial knee pain and compare it with conservative treatment. Materials and Methods: A total of 196 patients were recruited for this trial and initially treated conservatively with oral analgesics and exercise. At the end of 2 and 4 weeks from the inclusion date, they were offered a crossover to the intervention with ACB for the saphenous nerve. The outcome measures, such as Visual Analogue Scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, Timed Up and Go test, number of analgesics ingested per day and World Health Organization Quality of Life-BREF (WHOQoL-BREF) scores, were recorded at pre-decided time points. Results: After multiple structured follow-ups, 76 and 86 patients were analysed in the intervention and conservative groups, respectively. The two groups had no significant differences in the demographic and clinical patterns. The intervention group showed improvements in VAS (at week 2) (P < 0.05), WOMAC and the number of analgesics ingested per day (weeks 2 and 4) (P < 0.05). At ‘week 8’ follow-up, most patient outcomes including physical health and psychological domains of WHOQoL-BREF scores were better for conservative group (P < 0.05). The rest of the outcome measures were comparable for both groups at all time points. No adverse events were reported. Conclusion: This study suggests that ACB is effective only for a short duration and does not offer any significant advantage over conservative management in the long run.

Development of International Classification of Functioning, Disability, and Health Core Sets for Lower Extremity Osteoarthritis within Indian Context: A Study Protocol

Abstract Background: Properly understanding the functioning and health status of lower extremity osteoarthritis (LEOA) is needed to optimize interventions to enhance function and minimize disability. The available International Classification of Functioning, Disability, and Health (ICF) Core Sets (CS) for osteoarthritis are not specific to the lower extremity. They are strongly influenced by Western sociocultural values that may be inappropriate in the Indian context. Therefore, the objective of this study is to present the proposed process for the development of the ICF CS for LEOA, specifically for the Indian population. Materials and Methods: The first stage is to identify ICF categories significant for LEOA using four preparatory studies: (a) a systematic literature review to compile the researcher’s perspective by identifying functional outcome measures, (b) a qualitative study using focus group interviews to identify patients’ perspective, (c) an expert survey to identify experts’ perspective, and (d) a cross-sectional, multicenter study. The first version of the comprehensive and brief ICF-CS for LEOA will be developed through a consensus process using a Delphi exercise, integrating the evidence from the preparatory studies. In the final stage, field testing on Indian patients will validate the first version of the CS for LEOA. Conclusion: The proposed protocol to develop ICF-CS for LEOA may provide the basis for a generally agreed-upon standard that allows a comparison of functioning in clinical practice, research studies, quality management, and reimbursement that are relevant for patients with LEOA and health-care providers in Indian contexts.

Impact of Hip and Knee Osteoarthritis on Full Body Sagittal Alignment and Compensation for Sagittal Spinal Deformity.

Retrospective review of prospectively collected data. To investigate the effect of lower extremity osteoarthritis on sagittal alignment and compensatory mechanisms in adult spinal deformity (ASD). Spine, hip, and knee pathologies often overlap in ASD patients. Limited data exists on how lower extremity osteoarthritis impacts sagittal alignment and compensatory mechanisms in ASD. In total, 527 preoperative ASD patients with full body radiographs were included. Patients were grouped by Kellgren-Lawrence grade of bilateral hips and knees and stratified by quartile of T1-Pelvic Angle (T1PA) severity into low-, mid-, high-, and severe-T1PA. Full-body alignment and compensation were compared across quartiles. Regression analysis examined the incremental impact of hip and knee osteoarthritis severity on compensation. The mean T1PA for low-, mid-, high-, and severe-T1PA groups was 7.3°, 19.5°, 27.8°, and 41.6°, respectively. Mid-T1PA patients with severe hip osteoarthritis had an increased sagittal vertical axis and global sagittal alignment ( P <0.001). Increasing hip osteoarthritis severity resulted in decreased pelvic tilt ( P =0.001) and sacrofemoral angle ( P <0.001), but increased knee flexion ( P =0.012). Regression analysis revealed that with increasing T1PA, pelvic tilt correlated inversely with hip osteoarthritis and positively with knee osteoarthritis ( r2 =0.812). Hip osteoarthritis decreased compensation through sacrofemoral angle (β-coefficient=-0.206). Knee and hip osteoarthritis contributed to greater knee flexion (β-coefficients=0.215, 0.101; respectively). For pelvic shift, only hip osteoarthritis significantly contributed to the model (β-coefficient=0.100). For the same magnitude of spinal deformity, increased hip osteoarthritis severity was associated with worse truncal and full body alignment with posterior translation of the pelvis. Patients with severe hip and knee osteoarthritis exhibited decreased hip extension and pelvic tilt but increased knee flexion. This examines sagittal alignment and compensation in ASD patients with hip and knee arthritis and may help delineate whether hip and knee flexion is due to spinal deformity compensation or lower extremity osteoarthritis.

Preoperative and Postoperative Weight Change has Minimal Influence on Health Care Utilization and Patient-Reported Outcomes Following Total Knee Arthroplasty.

As obesity becomes more prevalent, more patients are at risk of lower extremity osteoarthritis and subsequent total knee arthroplasty (TKA). This study aimed to test (1) the association of preoperative weight change with health care utilization and (2) the association of pre- and postoperative weight changes with failure to achieve satisfaction and minimal clinically important difference (MCID) in Knee injury and Osteoarthritis Outcome Score for pain (KOOS-Pain) and function (KOOS-PS) 1 year after TKA. Prospectively collected monocentric data on patients who underwent primary TKA were retrospectively reviewed. Multivariable logistic regression assessed the influence of BMI and weight change on outcomes while controlling for confounding variables. Outcomes included prolonged length of stay (LOS >3 days), nonhome discharge, 90-day readmission rate, satisfaction, and achievement of MCID for KOOS-Pain and KOOS-PS. Preoperative weight change had no impact on prolonged LOS (gain, p = 0.173; loss, p = 0.599). Preoperative weight loss was associated with increased risk of nonhome discharge (odds ratio [OR]: 1.47, p = 0.003). There was also increased risk of 90-day readmission with preoperative weight gain (OR: 1.27, p = 0.047) and decreased risk with weight loss (OR: 0.73, p = 0.033). There was increased risk of nonhome discharge with obesity class II (OR: 1.6, p = 0.016) and III (OR: 2.21, p < 0.001). Weight change was not associated with failure to achieve satisfaction, MCID in KOOS-Pain, or MCID in KOOS-PS. Obesity class III patients had decreased risk of failure to reach MCID in KOOS-Pain (OR: 0.43, p = 0.005) and KOOS-PS (OR: 0.7, p = 0.007). Overall, pre- and postoperative weight change has little impact on the achievement of satisfaction and clinically relevant differences in pain and function at 1 year. However, preoperative weight gain was associated with a higher risk of 90-day readmissions after TKA. Furthermore, patients categorized in Class III obesity were at increased risk of nonhome discharge but experienced a greater likelihood of achieving MCID in KOOS-Pain and KOOS-PS. Our results raise awareness of the dangers of using weight changes and BMI alone as a measure of TKA eligibility.

Do Indian Researchers Consider Functioning Issues of Lower Extremity Osteoarthritis: A Scoping Review

Lower extremity osteoarthritis (LEOA) is a noncommunicable disease with an increasing burden globally, especially the developing countries like India. Understanding the functioning issue is needed to address individuals’ daily problems. Knowing how Indian researchers consider functioning will aid in understanding the current research trend. This scoping review describes the nature and extent to which the Indian researchers considered the functioning issues of LEOA individuals and linked them with the International Classification of Functioning, Disability, and Health (ICF) categories. We conducted an electronic database search of PubMed, Cochrane Library, and Pedro for Indian studies related to the functional issue of LEOA. Keeping the standard of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses- extension for scoping reviews (ScR) guidelines, we identified 102 related articles and included 28 that match the selection criteria. We observed a limited focus on functioning issues by Indian researchers. The researchers mainly rely on functional outcome measures while considering the functioning issue of LEOA. Most Western sociocultural influence outcome measures used by the studies were linked with activity limitation and participation restriction of ICF categories only. There is an urgent need for Indian researchers across professions to employ the ICF as a conceptual framework to understand and address the functioning issues associated with LEOA comprehensively.

Effect of Lower Extremity Osteoarthritis on Outcomes of Lumbar Decompression.

The purpose of this study is to evaluate how hip or knee osteoarthritis (OA) and total joint arthroplasty impact the outcomes of patients undergoing lumbar decompression. A retrospective review of 342 patients undergoing lumbar decompression without fusion from January 2019 and June 2021 at a single institution was performed. Univariate and multivariate analyses were used to compare outcomes between patients with and without concomitant hip or knee OA. Forty-six percent of patients had a hip or knee OA diagnosis and were higher risk as they were older, had higher BMIs, were more likely to be former smokers, had higher ASA scores, and were more likely to undergo 3+ level surgery. Postoperatively, after adjusting for differences between groups, hip or knee OA patients were more likely to be readmitted (OR=12.45, p=0.026) or have a complication (OR=13.77, p=0.031). However, patient reported outcomes as measured by Patient Reported Outcomes Measurement Information System-physical function. were similar at 1-3 months and 3-6 months. Higher levels of physical function were observed at 3-6 months postoperatively in hip OA patients with a history of THA. Patients with concomitant hip or knee OA are at higher risk for readmission and postoperative complications but may achieve similar levels of physical function as those without OA.

The relationships between pain-associated psychological distress, pain intensity, patient expectations, and physical function in individuals with musculoskeletal pain: A retrospective cohort study.

The presence of pain-associated psychological distress (PAPD) in musculoskeletal disorders, including negative mood, fear-avoidance, and lack of positive affect/coping, is associated with prolonged disability. The importance of considering psychological influence on pain is well known, but practical ways of addressing it are not as straightforward. Identifying relationships between PAPD and pain intensity, patient expectations, and physical function may guide the development of future studies that assess causality and inform clinical practice. To assess the relationship between PAPD measured by the Optimal Screening for Prediction of Referral and Outcome-Yellow Flag tool, and baseline pain intensity, expectations of treatment effectiveness, and self-reported physical function at discharge. Retrospective cohort study. Hospital-based outpatient physical therapy. Patients 18 to 90 years old with spinal pain or lower extremity osteoarthritis. Pain intensity and patient expectations of treatment effectiveness at intake, and self-reported physical function at discharge. A total of 534 patients, 56.2% female, median (interquartile range [IQR]) age 61 (21) years with an episode of care between November 2019 and January 2021 were included. A multiple linear regression showed a significant association between PAPD and pain intensity with 6.4% (p < .001) of the variance explained. PAPD explained 3.3% (p < .001) of the variance in patient expectations. One additional yellow flag present resulted in a 0.17-point increase in pain intensity and 1.3% decrease in patient expectations. PAPD was also associated with physical function with 3.2% (p < .001) of the variance explained. PAPD explained 9.1% (p < .001) of the variance in physical function at discharge in the low back pain cohort only when assessed independently by body region. These findings support the theory that the pain experience is complex and multiple factors should be considered when evaluating a patient with musculoskeletal pain. Clinicians who have identified PAPD may consider these relationships when planning or modifying interventions and pursuing multidisciplinary collaboration.

Joint Injury, Osteoarthritis, and Cardiovascular Disease Risk Factors in Former National Football League Athletes: An NFL-LONG Study.

Individuals with lower extremity osteoarthritis (OA) have a 25% greater risk of cardiovascular disease (CVD) than those without OA. The prevalence of traumatic joint injuries among National Football League (NFL) players exposes these athletes to an elevated risk for OA and potentially a greater risk of cardiovascular risk factors (CRFs) and CVD. To examine the associations between a history of lower extremity joint injury, lower extremity OA, and the prevalence of CRFs and CVD among former NFL athletes. Cross-sectional study. Former NFL players completed a comprehensive health questionnaire that was used in an ongoing study, the Neurologic Function Across the Lifespan: A Prospective, Longitudinal, and Translational Study for Former NFL Players (NFL-LONG). A subsample of 1738 former players reported lifetime medical diagnoses including CVD or CRFs. Crude and adjusted prevalence ratios (PRsadj) characterized the associations between CVD or CRFs and injury, OA diagnosis, or both among athletes who reported (1) no history of lower extremity joint injury or surgery and no diagnosed OA, (2) a history of lower extremity joint injury or surgery and no diagnosed OA, and (3) a history of lower extremity joint injury or surgery and diagnosed OA. Neither a history of lower extremity joint injury (PRadj = 1.34; 95% CI = 0.86, 2.07) nor a history of lower extremity joint injury and diagnosed OA (PRadj = 1.41; 95% CI = 0.89, 2.25) was significantly associated with CVD. However, CRFs were 30% and 53% more prevalent in former players with lower extremity joint injury and no diagnosed OA (PRadj = 1.30; 95% CI = 1.12, 1.50) and those with lower extremity joint injury and diagnosed OA (PRadj = 1.53; 95% CI = 1.31, 1.78), respectively, versus athletes with no history of either condition. The prevalence of CRFs was highest among former NFL athletes with a history of lower extremity joint injury and diagnosed OA. These findings provide insight regarding the potential pathways to chronic diseases that may be initiated by joint injury early in life.

Relationship between lumbar facet joint osteoarthritis and comorbidities: A cross-sectional study in the Japanese community

BackgroundFew epidemiological studies have evaluated associations between lumbar facet joint (LFJ) osteoarthritis (OA) and comorbidities. This study aimed to investigate the prevalence of LFJ OA in a Japanese community population and associations between LFJ OA and underlying diseases, including lower extremity OA. MethodsThis epidemiological cross-sectional study evaluated LFJ OA in 225 Japanese community residents (81 males, 144 females; median age, 66 years) using magnetic resonance imaging (MRI). LFJ OA from L1–L2 to L5–S1 was evaluated using a 4-grade classification. Associations between LFJ OA and comorbidities were examined using multiple logistic regression analyses adjusting for age, sex, and body mass index. ResultsPrevalences of LFJ OA were 28.6% at L1–L2, 36.4% at L2–L3, 48.0% at L3–L4, 57.3% at L4–L5, and 44.2% at L5–S1. Males were significantly more likely to have LFJ OA at several spinal levels (L1–L2 45.7% vs 18.9%, p < 0.001; L2–L3 46.9% vs 30.6%, p < 0.05; L4–L5 67.9% vs 51.4%, p < 0.05). LFJ OA was present in 50.0% of residents <50 years old, 68.4% at 50–59 years old, 86.3% at 60–69 years old, and 85.1% at ≥70 years old. Multiple logistic regression analysis showed no associations between LFJ OA and comorbidities. ConclusionsThe prevalence of LFJ OA as evaluated by MRI was >85% at ≥60 years old and highest at the L4–L5 spinal level. Males were significantly more likely to have LFJ OA at several spinal levels. Comorbidities were not associated with LFJ OA.

The Association of Metabolic Syndrome and Obesity With Clinical Hip Osteoarthritis in the Study of Osteoporotic Fractures and the Osteoporotic Fractures in Men Study Cohorts.

Metabolic dysregulation frequently co-occurs with obesity, which has been shown to be a risk factor for lower extremity osteoarthritis (OA). We evaluated the association between metabolic syndrome (MetS), alone and in combination with obesity, and hip OA. In two parallel cross-sectional analyses, we studied 403 women from the Study of Osteoporotic Fractures (SOF) and 2354 men from the Osteoporotic Fractures in Men (MrOS) study. We used multivariable logistic regression to evaluate associations of obesity (body mass index ≥30 kg/m2 ) and/or MetS (three of five National Cholesterol Education Program Adult Treatment Panel III criteria) with clinical hip OA, defined as a modified Croft score of 2 or more or total hip replacement, and pain or limited range of motion. Our analysis adjusted for demographics. Approximately 3.5% of SOF women and 5.4% of MrOS men had clinical hip OA. Among women, obesity was not associated with hip OA, yet those with MetS had a 365% higher odds of hip OA (95% CI: 1.37-15.83). Among men, those who had obesity had a 115% higher odds of hip OA (95% CI: 1.39-3.32), yet MetS was not associated with hip OA. There was no interaction between MetS, obesity, and hip OA in either women or men. In women, but not in men, MetS was associated with hip OA. In men, but not in women, obesity was associated with hip OA. These findings suggest that mechanical effects of obesity may predominate in the pathogenesis of hip OA in men, whereas metabolic effects predominate in women.

Sagittal spinal alignment and mobility and their relation to physical function in women with and without mild-to-moderate knee osteoarthritis

Recent studies suggest that patients with lower extremity osteoarthritis may have altered spinal posture. We aimed to investigate age and body mass index-adjusted sagittal spinal alignment and mobility and their relation to physical function in women over 40 years of age with and without mild-to-moderate knee osteoarthritis (KOA). Thirty-two women with unilateral mild-to-moderate KOA and thirty-two asymptomatic women were included. A skin-surface device was used to assess sagittal alignment and mobility of the thoracic, lumbar, and sacral regions and trunk inclination angle. Physical function was assessed using the Timed Up and Go test. Analysis of covariance was used to compare groups and correlation coefficients were calculated separately for two groups. Women with KOA had higher thoracic kyphosis and lumbar lordosis compared to asymptomatic women (p < 0.05). The mean differences were 6.60 (%95 Confidence Interval 1.38;11.82) and −5.63 (−10.06;−1.20) for thoracic kyphosis and lumbar lordosis, respectively. Physical function score was moderately correlated with trunk inclination angle and lumbar, sacral, and trunk inclination mobility in asymptomatic women (r = 0.400, −0.504, −0.602, and −0.681, p < 0.05), but a significant correlation was not found in women with KOA (p > 0.05). In conclusion, women with KOA had altered spinal alignment. Spinal alignment and mobility were related to physical function in asymptomatic women over 40 years of age. Addressing sagittal spinal alignment in the clinical management of KOA may provide valuable data, especially for preventing possible spinal disorders.

Effects of a Fall Prevention Program Based on Goal Attainment Theory for Homebound Older Adults With Osteoarthritis of the Lower Extremities.

This study implemented and evaluated a community-based fall prevention program based on goal attainment theory that targeted older adults with osteoarthritis. The program included education, exercise, and one-on-one counseling during which the participant and the provider set individual fall prevention goals. This study used a nonequivalent control group pre-/posttest design. Participants were older adults in senior centers with lower extremity osteoarthritis. A fall prevention program in the experimental group included group (70 minutes, once/week; education and exercise) and individual counseling (10 minutes, twice/week; emotional support and goal setting). Data analysis was conducted using SPSS/WIN 22.0 with the χ2 test, Fisher's exact test, independent t test, and Mann-Whitney U test. The experimental group experienced significantly fewer falls, less stiffness, less difficulty performing activity; more muscular strength, walking ability, and balance; as well as less fear of falling and higher falls efficacy in comparison with the control group. However, pain did not improve in either of the two groups. Fall prevention programs need to include the active involvement of carers in ensuring environmental changes to reduce fall risks. In addition, health professionals who care for community patients with osteoarthritis could strengthen interactions and exchanges to prevent falls and actively modify home hazards.

Biomechanical biofeedback applications of wearable sensor technology in the management of lower extremity osteoarthritis: Scoping review

Biomechanical biofeedback applications of wearable sensor technology in the management of lower extremity osteoarthritis: Scoping review

Point-of-care motion capture and biomechanical assessment improve clinical utility of dynamic balance testing for lower extremity osteoarthritis.

Musculoskeletal conditions impede patient biomechanical function. However, clinicians rely on subjective functional assessments with poor test characteristics for biomechanical outcomes because more advanced assessments are impractical in the ambulatory care setting. Using markerless motion capture (MMC) in clinic to record time-series joint position data, we implemented a spatiotemporal assessment of patient kinematics during lower extremity functional testing to evaluate whether kinematic models could identify disease states beyond conventional clinical scoring. 213 trials of the star excursion balance test (SEBT) were recorded by 36 subjects during routine ambulatory clinic visits using both MMC technology and conventional clinician scoring. Conventional clinical scoring failed to distinguish patients with symptomatic lower extremity osteoarthritis (OA) from healthy controls in each component of the assessment. However, principal component analysis of shape models generated from MMC recordings revealed significant differences in subject posture between the OA and control cohorts for six of the eight components. Additionally, time-series models of subject posture change over time revealed distinct movement patterns and reduced overall postural change in the OA cohort compared to the controls. Finally, a novel metric quantifying postural control was derived from subject specific kinematic models and was shown to distinguish OA (1.69), asymptomatic postoperative (1.27), and control (1.23) cohorts (p = 0.0025) and to correlate with patient-reported OA symptom severity (R = -0.72, p = 0.018). Time series motion data have superior discriminative validity and clinical utility than conventional functional assessments in the case of the SEBT. Novel spatiotemporal assessment approaches can enable routine in-clinic collection of objective patient-specific biomechanical data for clinical decision-making and monitoring recovery.

Inertial Measurement Units and Application for Remote Health Care in Hip and Knee Osteoarthritis: Narrative Review.

BackgroundMeasuring and modifying movement-related joint loading is integral to the management of lower extremity osteoarthritis (OA). Although traditional approaches rely on measurements made within the laboratory or clinical environments, inertial sensors provide an opportunity to quantify these outcomes in patients’ natural environments, providing greater ecological validity and opportunities to develop large data sets of movement data for the development of OA interventions.ObjectiveThis narrative review aimed to discuss and summarize recent developments in the use of inertial sensors for assessing movement during daily activities in individuals with hip and knee OA and to identify how this may translate to improved remote health care for this population.MethodsA literature search was performed in November 2018 and repeated in July 2019 and March 2021 using the PubMed and Embase databases for publications on inertial sensors in hip and knee OA published in English within the previous 5 years. The search terms encompassed both OA and wearable sensors. Duplicate studies, systematic reviews, conference abstracts, and study protocols were also excluded. One reviewer screened the search result titles by removing irrelevant studies, and 2 reviewers screened study abstracts to identify studies using inertial sensors as the main sensing technology and a primary outcome related to movement quality. In addition, after the March 2021 search, 2 reviewers rescreened all previously included studies to confirm their relevance to this review.ResultsFrom the search process, 43 studies were determined to be relevant and subsequently included in this review. Inertial sensors have been successfully implemented for assessing the presence and severity of OA (n=11), assessing disease progression risk and providing feedback for gait retraining (n=7), and remotely monitoring intervention outcomes and identifying potential responders and nonresponders to interventions (n=14). In addition, studies have validated the use of inertial sensors for these applications (n=8) and analyzed the optimal sensor placement combinations and data input analysis for measuring different metrics of interest (n=3). These studies show promise for remote health care monitoring and intervention delivery in hip and knee OA, but many studies have focused on walking rather than a range of activities of daily living and have been performed in small samples (<100 participants) and in a laboratory rather than in a real-world environment.ConclusionsInertial sensors show promise for remote monitoring, risk assessment, and intervention delivery in individuals with hip and knee OA. Future opportunities remain to validate these sensors in real-world settings across a range of activities of daily living and to optimize sensor placement and data analysis approaches.

Lower Extremity Osteoarthritis: A Risk Factor for Mental Health Disorders, Prolonged Opioid Use, and Increased Resource Utilization After Single-Level Lumbar Spinal Fusion.

Introduction:Few studies have examined the effect of hip or knee osteoarthritis, together described as lower extremity osteoarthritis (LEOA) on patient outcomes after lumbar fusion. The purpose of this study was to evaluate the effect of LEOA on postoperative outcomes and resource utilization in patients undergoing single-level lumbar fusion.Methods:Using a national deidentified database, TriNetX, a retrospective observational study of 17,289 patients undergoing single-level lumbar fusion with or without a history of LEOA before September 1, 2019, was conducted. The no-LEOA and LEOA groups were propensity score matched, and 2-year outcomes were compared using univariate statistical analysis.Results:After propensity score matching, 2289 patients with no differences in demographics or comorbidities remained in each group. No differences in the rate of repeat lumbar surgery were observed between groups (all P > 0.30). In comparison with patients with no LEOA, patients with LEOA experienced higher rates of overall and new onset depression or anxiety, prolonged opioid use, hospitalizations, emergency department visits, and ambulatory visits over the 2-year postoperative period (all P < 0.02).Conclusion:Patients with LEOA undergoing single-level lumbar fusion surgery are at higher risk for suboptimal outcomes and increased resource utilization postoperatively. This complex population may benefit from additional individualized education and multidisciplinary management.

Association of Combined Slow Gait and Low Activity Fragmentation With Later Onset of Cognitive Impairment

Among older people, slow walking is an early indicator of risk for Alzheimer disease (AD). However, studies that have assessed this association have not considered that slow walking may have different causes, some of which are not necessarily associated with higher AD risk. To evaluate whether low activity fragmentation among older adults with slow gait speed indicates neurological causes of slow walking that put these individuals at higher risk of AD. This prospective cohort study performed survival analyses using data from the Baltimore Longitudinal Study of Aging. Participants included 520 initially cognitively normal persons aged 60 years or older. New diagnoses of mild cognitive impairment (MCI) or AD were adjudicated during a mean (SD) follow-up of 7.3 (2.7) years. Initial assessment of gait speed and activity fragmentation occurred from January 3, 2007, to May 11, 2015, with follow-up completed on December 31, 2020. Data were analyzed from February 1 to May 15, 2021. Gait speed for 6 m and activity fragmentation assessed by accelerometry. Associations of gait speed, activity fragmentation, and their interaction with incident MCI/AD were evaluated using Cox proportional hazards models, adjusted for covariates. Among the 520 participants (265 women [51.0%]; 125 Black participants [24.0%]; 367 White participants [70.6%]; mean [SD] age, 73 [8] years), MCI/AD developed in 64 participants. Each 0.05-m/s slower gait was associated with a 7% increase in risk of developing MCI/AD (hazard ratio [HR], 1.07 [95% CI, 1.00-1.15]; P = .04). Activity fragmentation alone was not associated with MCI/AD risk (HR, 0.83 [95% CI, 0.56-1.23]; P = .35), but there was a significant interaction between gait speed and activity fragmentation (HR, 0.92 [95% CI, 0.87-0.98]; P = .01). At low activity fragmentation (-1 SD), each 0.05-m/s slower gait speed was associated with a 19% increase in hazard of developing MCI/AD (HR, 1.19 [95% CI, 1.07-1.32]), whereas at higher activity fragmentation (+1 SD), gait speed was not associated with MCI/AD (HR, 1.01 [95% CI, 0.93-1.10]). Among participants with slow gait, higher activity fragmentation was associated with higher odds of having lower extremity osteoarthritis (odds ratio, 1.31 [95% CI, 1.01-1.69]) and less decline in pegboard dominant hand performance (β = 0.026 [SE, 0.009]; P > .05). These findings suggest that frequent rests among older adults with slow gait speed are associated with lower risk of future MCI/AD and that this behavioral strategy is associated with a lower likelihood of subclinical neurological impairment.

The Impact of Total Joint Arthroplasty on Long-Term Physical Activity: A Secondary Analysis of the Health and Retirement Study.

Physical inactivity is the fourth-leading cause of global mortality and is prevalent among people with lower extremity osteoarthritis. Lower extremity osteoarthritis is the most common arthritis type afflicting older adults, and total joint arthroplasty (TJA) performed to address the condition is Medicare's largest annual expense. Despite TJA intervention to address the disabling effects of osteoarthritis, physical activity (PA) level remains stable 6months after TJA; however, the effect of TJA on long-term PA $(\ge$2 y) in a representative sample of older adults is unknown. The purpose of this study was to test the hypothesis that PA would remain stable in the long term. In this longitudinal observational study, a probability-weighted difference-in-differences analysis was conducted to observe the predictive margins of nontraumatic hip or knee TJA on levels of vigorous and moderate PA after 2years. A combined Health and Retirement Study data set of community-dwelling adults who were >55years old, had symptomatic osteoarthritis, and were in need of TJA between 2008 and 2018 (N = 4652) was used. TJA was not associated with vigorous PA ($\delta$ = 2.37; SE = 5.23) or moderate PA ($\delta$ = -2.84; SE = 7.76) after 2years. TJA was not associated with increased long-term PA in older adults with osteoarthritis. Physical therapists should not assume that there will be a natural increase in PA after functional recovery from TJA procedures. Older adults with lower extremity osteoarthritis may benefit from PA screening and promotion practices in physical therapy services. Receiving a total joint replacement does not lead to increased physical activity levels 2years after surgery.

Predicting Alzheimer's Disease from Combined Slow Gait and Low Activity Fragmentation - is Activity Fragmentation Always Bad?

Background: Among older people, slow walking is a mild predictor of Alzheimer's disease (AD). However, studies that assessed this association did not consider slow walking may have different causes and that the increased risk of AD may be limited to a subgroup. We hypothesized that individuals with slow walking who show frequent alternative bouts of activity and rest are more likely to have non-neurological causes of slow walking, while those who fail to use this compensatory strategy despite slow walking are more likely to have neurological causes that put them at higher risk of AD. Methods: We analyzed data on gait speed and activity fragmentation (AF) by accelerometry from 505 initially cognitively normal persons aged 60 and older (51%women, 24%Black). New diagnoses of mild cognitive impairment (MCI) or AD were adjudicated over a mean of 7·2-years. Associations of gait speed, AF, and their interaction with incident MCI/AD were evaluated by Cox proportional-hazards models, adjusted for covariates. Findings: MCI/AD developed in 64 participants. Each 0·05m/sec slower gait speed was associated with 8% higher risk of MCI/AD (p=0·03). AF alone was not associated with MCI/AD risk (p>0·05), but we found a significant “gait*AF” interaction (p=0·02). At low AF (-1SD), each 0·05 m/sec slower gait speed was associated with 16% higher risk of MCI/AD, while at higher AF (+1SD), gait speed did not predict MCI/AD. Among those with slow gait, higher AF was associated with less decline in pegboard dominant hand performance, higher odds of having lower extremity osteoarthritis, and higher cardiopulmonary burden. Interpretation: Frequent rests among slow walkers are associated with lower risk of future MCI/AD, perhaps because this behavioral strategy indicates lower likelihood of subclinical brain damage. On the contrary, failing to fragment activity in the face of impaired mobility may indicate subclinical brain damage and, therefore, is predictive of MCI/AD. Funding: This study was supported in part by the Intramural Research Program of the National Institute on Aging. Declaration of Interest: None declared. Ethical Approval: The BLSA protocol was approved by the Institutional Review Board of the National Institutes of Health. Participants provided written informed consent at each BLSA visit.