Asymmetric running is associated with pain during outdoor running in individuals with Achilles tendinopathy in the return-to-sport phase.

OBJECTIVES: To determine the relationships between (1) Achilles tendon pain and loading symmetry, and (2) number of running bouts and symptom severity, during two weeks of outdoor running in individuals with Achilles tendinopathy. DESIGN: Prospective, observational study. SETTING: Biomechanics laboratory and outdoors. PARTICIPANTS: Seventeen runners with Achilles tendinopathy in the return-to-sport phase of rehabilitation. MAIN OUTCOME MEASURES: Symptom severity was recorded with the Victorian Institute of Sports Assessment-Achilles (VISA-A) questionnaire. Running bouts and Achilles tendon pain during runs were recorded with daily training logs. Ground contact time was collected during runs with wearable sensors. Linear mixed modeling determined if the relationship between Achilles tendon pain and ground contact time symmetry during running was moderated by consecutive run days. Multiple regression determined the relationship between number of running bouts and change in VISA-A scores over two weeks, adjusted for run distance. RESULTS: Greater ground contact time on the contralateral leg corresponded to increased ipsilateral tendon pain for each consecutive run day (b = -0.028, p < 0.001). Number of running bouts was not associated with 2-week changes in VISA-A scores (p = 0.672). CONCLUSIONS: Pain during running is associated with injured leg off-loading patterns, and this relationship strengthened with greater number of consecutive run days. Number of running bouts was not related to short-term symptom severity.

Potentially inappropriate medication use among older adults with lower-limb loss.

OBJECTIVE: The aim of this study was to evaluate the prevalence of, and explore factors related to, prescription of potentially inappropriate medications (PIMs) among older adults with lower-limb loss (LLL). METHODS: This was a secondary analysis of a cross-sectional dataset collected through an interdisciplinary limb loss clinic between September 2013 and November 2022. Self-report medication lists were reviewed during in-clinic face-to-face interviews and compared to the American Geriatrics Society Beers Criteria corresponding to the patient's evaluation year. RESULTS: Of 82 participants (72.9 ± 6.6 years-old; 78.0 % male), n = 41 (50.0 %) reported using one or more PIM. PIM prescription was significantly associated with presence of phantom limb pain, history of upper gastrointestinal issues, and a greater number of medications. DISCUSSION: Polypharmacy and PIM use are common among older adults with LLL. Greater attention should be paid to medications post-amputation, especially pain management medications, to minimize potential adverse side-effects.

Immediate and Short-Term Effects of In-Shoe Heel-Lift Orthoses on Clinical and Biomechanical Outcomes in Patients With Insertional Achilles Tendinopathy.

Background: Physical therapists frequently employ heel lifts as an intervention to reduce Achilles tendon pain and restore function. Purpose: To determine the short-term effect of heel lifts on clinical and gait outcomes in participants with insertional Achilles tendinopathy (IAT). Study Design: Case series; Level of evidence, 4. Methods: Participants with IAT underwent eligibility screening and completed assessments at baseline and 2 weeks later. Primary outcomes included symptom severity (Victoria Institute of Sports Assessment-Achilles [VISA-A]), gait analysis with the 10-m walk-test at 2 speeds (normal and fast), and pain during walking. Pain and gait analysis were assessed under 3 conditions: before fitting 20-mm heel lifts, immediately after heel-lift fitting, and after 2 weeks of wearing heel lifts. Ultrasound images and measurements at the Achilles insertion were obtained from prone and standing positions (with and without heel lifts). Spatiotemporal gait parameters and tibial tilt angles were evaluated at normal speed using inertia measurement units during the 3 study conditions. Differences between the conditions were analyzed using paired t test or analysis of variance. Results: Overall, 20 participants (12 female, 13 with bilateral IAT; mean age, 51 ± 9.3 years; mean body mass index 31.6 ± 6.8 kg/m2) completed all assessments. Symptom severity (VISA-A) of the more symptomatic side significantly improved at 2 weeks (60 ± 20.6) compared with baseline (52.2 ± 20.4; P < .01). Pain during gait (Numeric Pain Rating Scale) was significantly reduced immediately after heel-lift fitting (0.7 ± 2.0) when compared with baseline (2.2 ± 2.7, P = .043). Spatiotemporal gait parameters and tibial tilt angle before and after using heel lifts at normal walking speed were not significantly different; however, gait speed, stride length, and tibial tilt angle on both sides increased significantly immediately after using heel lifts and were maintained after 2 weeks of wear. Conclusion: Using heel lifts not only improved symptom severity after 2 weeks but also immediately reduced pain during gait and had a positive impact on gait pattern and speed.

Efficacy and safety of using auditory-motor entrainment to improve walking after stroke: a multi-site randomized controlled trial of InTandemTM.

Walking slowly after stroke reduces health and quality of life. This multi-site, prospective, interventional, 2-arm randomized controlled trial (NCT04121754) evaluated the safety and efficacy of an autonomous neurorehabilitation system (InTandemTM) designed to use auditory-motor entrainment to improve post-stroke walking. 87 individuals were randomized to 5-week walking interventions with InTandem or Active Control (i.e., walking without InTandem). The primary endpoints were change in walking speed, measured by the 10-meter walk test pre-vs-post each 5-week intervention, and safety, measured as the frequency of adverse events (AEs). Clinical responder rates were also compared. The trial met its primary endpoints. InTandem was associated with a 2x larger increase in speed (Δ: 0.14 ± 0.03 m/s versus Δ: 0.06 ± 0.02 m/s, F(1,49) = 6.58, p = 0.013), 3x more responders (40% versus 13%, χ2(1) ≥ 6.47, p = 0.01), and similar safety (both groups experienced the same number of AEs). The auditory-motor intervention autonomously delivered by InTandem is safe and effective in improving walking in the chronic phase of stroke.

A Clinical Measure of Trunk Neuromuscular Function Predicts Falling in Older Adults With Chronic Low Back Pain.

BACKGROUND AND PURPOSE: Older adults with low back pain (LBP) are at risk for falling, but condition-specific mechanisms are unknown. Trunk neuromuscular function is critical for maintaining balance during mobility tasks and is often impaired in older adults with LBP. The purpose of this study was to assess whether aberrant lumbopelvic movements (or aberrant movements), a clinical index of trunk neuromuscular function, were associated with increased fall risk among older adults with chronic LBP over a 12-month follow-up period. METHODS: This study analyzed data from a prospective cohort study of 250 community-dwelling older adults with chronic LBP. Participants were screened for 4 aberrant movements during 3 trials of forward flexion from a standing position: instability catch, painful arc, altered lumbopelvic rhythm, and Gower's sign. Aberrant movements were totaled to yield a summary score (ie, 0-4). Prospective falls were monitored via monthly fall calendars for 12 months. A generalized linear model with Poisson distribution and log link function was used to evaluate the association between aberrant movements and prospective fall risk. Age, sex, body mass index, LBP intensity, dynamic balance performance, prior falls, anxiolytic medication usage, and hip osteoarthritis characteristics were included as covariates in the model. RESULTS: Baseline aberrant movements were independently associated with greater fall risk (risk ratio = 1.249, 95% CI = 1.047-1.491, P = .014); each 1-unit increase in aberrant movement score imparted a 24.9% increase in the risk of falling. CONCLUSIONS: Aberrant movements increased the risk of falling among older adults with chronic LBP over a 1-year span.

Sex influences blood pressure but not blood pressure variability in response to dietary sodium and potassium in salt-resistant adults.

Dietary sodium and potassium have been shown to affect blood pressure (BP) but their influence on BP variability (BPV) is less studied as is the influence of sex. The aim of this study was to compare 24 h BP and short-term BPV in response to varying dietary levels of sodium and potassium in healthy non-obese normotensive salt-resistant adults. We hypothesized that high sodium would increase short-term BP and BPV while the addition of high potassium would counteract this increase. Furthermore, we hypothesized that women would experience greater increases in BPV under high sodium conditions compared to men while potassium would attenuate this response. Thirty-seven participants (17 M/20 W; 27 ± 5 years old; BMI 24.3 ± 3 kg/m2) completed seven days each of the following randomized diets: moderate potassium/low sodium (MK/LS), moderate potassium/high sodium (MK/HS) and high potassium/high sodium (HK/HS). BP and short-term BPV were assessed using 24 h ambulatory BP monitoring starting on day 6. BPV was calculated using the average real variability (ARV) index. Twenty-four hour, daytime, and nighttime systolic BP (SBP) were lower in women compared to men regardless of diet. However, 24 h and daytime SBP were lowered in women on the HK/HS diet compared to the MK/HS diet. There were no significant effects of diet or sex for 24 h, daytime or nighttime SBP ARV. However, men exhibited a higher 24 hDBP ARV than women regardless of diet. In conclusion, a high potassium diet lowered BP under high sodium conditions in women alone while men exhibited higher short-term BPV that was not influenced by diet.

Examining Psychological Factors as Contributors to Pain, Disability, and Physical Function in Geriatric Chronic Low Back Pain: A Prospective Analysis of the Delaware Spine Studies Cohort.

In younger populations, risk factors from psychologically-focused theoretical models have become accepted as primary drivers behind the persistence of low back pain (LBP), but these risk factors have not been thoroughly assessed in older adult populations (60-85 years). To address this knowledge gap, we sought to examine longitudinal associations between both general and pain-related psychological risk factors and future pain intensity, LBP-related disability, and physical function (gait speed) outcomes in older adults with chronic LBP (n = 250). Questionnaires for general (ie, depressive symptoms) and pain-related psychological risk factors (ie, fear-avoidance beliefs, pain catastrophizing, and kinesiophobia) were collected at baseline. Questionnaire values were entered into principal component analysis to yield a combined psychological component score. LBP intensity (pain thermometers), LBP-related disability (Quebec Back Pain Disability Scale), and gait speed were measured at baseline and 12-month follow-up. Multiple linear regression was used to examine adjusted associations between baseline psychological component scores and each prospective outcome. The baseline psychological component score failed to independently predict 12-month LBP-related disability and gait speed after adjustment for baseline outcomes. Though the psychological component score was associated with 12-month LBP intensity after adjusting for baseline LBP intensity, this association diminished with full adjustment for other baseline characteristics. Cumulatively, general and pain-related psychological risk factors did not independently predict longitudinal pain, disability, and physical function outcomes in this cohort. Compared to younger populations with this condition, general and pain-related psychological risk factors may have less influence on the maintenance of chronic LBP in older adults. PERSPECTIVE: This article failed to establish consistent independent relationships between psychological factors and worse longitudinal pain, disability, and physical function outcomes in older adults with chronic LBP. The findings highlight a need to determine other age-specific biopsychosocial risk factors that may impact the maintenance of chronic pain in this patient population.

Increasing Activity After Stroke: A Randomized Controlled Trial of High-Intensity Walking and Step Activity Intervention.

BACKGROUND: Physical inactivity in people with chronic stroke profoundly affects daily function and increases recurrent stroke risk and mortality, making physical activity improvements an important target of intervention. We compared the effects of a high-intensity walking intervention (FAST), a step activity monitoring behavioral intervention (SAM), or a combined intervention (FAST+SAM) on physical activity (ie, steps/day). We hypothesized the combined intervention would yield the greatest increase in steps/day. METHODS: This assessor-blinded multisite randomized controlled trial was conducted at 4 university/hospital-based laboratories. Participants were 21 to 85 years old, walking without physical assistance following a single, unilateral noncerebellar stroke of ≥6 months duration, and randomly assigned to FAST, SAM, or FAST+SAM for 12 weeks (2-3 sessions/week). FAST training consisted of walking-related activities at 70% to 80% heart rate reserve, while SAM received daily feedback and goal setting of walking activity (steps/day). Assessors and study statistician were masked to group assignment. The a priori-determined primary outcome and end point was a comparison of the change in steps/day between the 3 intervention groups from pre- to post-intervention. Adverse events were tracked after randomization. All randomized participants were included in the intent-to-treat analysis. RESULTS: Participants were enrolled from July 18, 2016, to November 16, 2021. Of 2385 participants initially screened, 250 participants were randomized (mean [SE] age, 63 [0.80] years; 116 females/134 males), with 89 assigned to FAST, 81 to SAM, and 80 to FAST+SAM. Steps/day significantly increased in both the SAM (mean [SE], 1542 [267; 95% CI, 1014-2069] P<0.001) and FAST+SAM group (1307 [280; 95% CI, 752-1861] P<0.001) but not in the FAST group (406 [238; 95% CI, -63 to 876] P=0.09). There were no deaths or serious study-related adverse events. CONCLUSIONS: Only individuals with chronic stroke who completed a step activity monitoring behavioral intervention with skilled coaching and goal progression demonstrated improvements in physical activity (steps/day). REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02835313.

Risk Factors for Underreporting of Life-Limiting Comorbidity Among Adults With Lower-Limb Loss.

Peripheral neuropathy (PN) and peripheral arterial disease (PAD) are life-limiting comorbidities among adults with lower-limb loss that may not be adequately addressed in current care models. The objective of this study was to evaluate underreporting of PN and PAD among adults with lower-limb loss. We conducted a secondary analysis of a cross-sectional dataset of community-dwelling adults with unilateral lower-limb loss seen in an outpatient Limb Loss Clinic (n = 196; mean age = 56.7 ± 14.4 years; 73.5% male). Individuals participated in standardized clinical examinations including Semmes-Weinstein monofilament testing to assess for PN and pedal pulse palpation to assess for PAD. Bivariate regression was performed to identify key variables for subsequent stepwise logistic regression to discern risk factors. Clinical examination results indicated 16.8% (n = 33) of participants had suspected PN alone, 15.8% (n = 31) had suspected PAD alone, and 23.0% (n = 45) had suspected PN and PAD. More than half of participants with clinical examination findings of PN or PAD failed to self-report the condition (57.7% and 86.8%, respectively). Among adults with lower-limb loss with suspected PN, participants with dysvascular amputations were at lower risk of underreporting (odds ratio [OR] = 0.2, 95% CI: 0.1-0.6). For those with suspected PAD, those who reported more medication prescriptions were at lower risk of underreporting (OR = 0.8, 95% CI: 0.7-1.0). Adults with lower-limb loss underreport PN and PAD per a medical history checklist, which may indicate underdiagnosis or lack of patient awareness. Routine assessment is highly recommended in this population and may be especially critical among individuals with non-dysvascular etiology.

High Compliance with the 11+ Injury Prevention Program Results in Better Win-Loss Records.

Background: The 11+ injury prevention program (IPP) has been shown to decrease injury rates. However, few studies have investigated compliance and its overall relationship to team performance. Hypothesis/Purpose: To examine if level of compliance while implementing the 11+ would impact team performance outcomes (wins, losses and ties). The authors hypothesized that higher team compliance to the IPP would be consistent with improved overall team performance (more wins and fewer losses). Study Design: Prospective, cluster randomized controlled trial. Methods: This study was conducted in NCAA men's soccer teams for one season and examined the efficacy of the 11+ IPP. The outcome variables examined were levels of compliance and team performance record: wins, losses, and ties. Twenty-seven teams (n=675 players) served as the intervention group (IG) and used the 11+ program while 34 teams (n=850 players) served as the control group (CG). Compliance and team performance were recorded. There were three compliance categories that were defined prospectively, low (LC, < 1 dose/week), moderate (MC, >1 and <2 doses/week), and high (HC, >2 doses/week). Descriptive and inferential tests were used to compare the CG, the IG, and compliance to team performance. Three independent t-tests were used to analyze outcome to group (IG vs. CG). A one way-MANOVA test was used to analyze compliance to win/loss/tie record, followed up by one-way ANOVA tests to analyze how compliance impacted wins, losses and ties, independently. Partial η2 measures were calculated to determine the effect size of level of compliance on outcome. A Tukey post-hoc analysis was used to analyze specific differences between levels of compliance and specific outcome measures. Results: There were significantly more wins (IG: 10.67±2.63 versus CG: 8.15±3.83, CI, 7.95 - 9.69, p = 0.005) and fewer losses (IG: 5.56±1.97 versus CG: 8.12±3.59, CI, 5.66 to 7.43, p = 0.002) recorded for the teams using the 11+ program. There was a statistically significant difference between levels of compliance (high, moderate or low) on the dependent variables (wins, losses, and ties), F(3, 22) = 3.780, p =0.004; Wilks' Λ = .435; partial η2 = .340. Conclusion: The 11+ has the capacity to improve overall team performance in male collegiate soccer teams. The higher the compliance, the more favorable the team performance. This research may be a vital addition when attempting to persuade coaching staffs to adopt an IPP into their training regimen. Level of Evidence: Level I.

How should the margin of stability during walking be expressed to account for body size?

When expressing the margin of stability as a distance, it does not directly estimate the perturbation magnitude needed to change stability states. Additionally, it is unknown how body size may influence this measure. Therefore, we propose other expressions of stability margins, including that of an impulse, a change in center of mass velocity, and a scaled, unitless impulse. The purpose of this study was to determine the influence of body size on these margin expressions using walking data from children and adults. We anticipated that margins expressed as an impulse would have strong correlations with body mass and height, as well as large between-group differences. We predicted that scaling this impulse value would result in small correlations and between-group effect sizes. We calculated each stability margin at minimum lateral values and in the anteroposterior directions at mid-swing and foot strike. In the lateral direction, margins expressed as an impulse had strong correlations with body size (r≥0.58, p<0.01) and large between-group differences (|d|≥1.07, p<0.01). The other expressions did not have strong positive correlations (|r|≤0.20) or large between-group effects (|d|≤0.44). In the anteroposterior directions, impulse margins had strong correlations with body size (|r|≥0.83, p<0.01) and large between-group differences (|d|≥1.74, p<0.01). The scaled, unitless impulse margin was the only variable that resulted in small, non-significant differences (|r|≤0.22, p≥0.24) as well as small between-group effect sizes (|d|≤0.46, p≥0.22). We propose expressing stability margins as an impulse. If scaling is needed, we encourage using the scaled, unitless impulse.

Increasing activity after stroke: a randomized controlled trial of highintensity walking and step activity intervention.

Background: Physical inactivity in people with chronic stroke profoundly affects daily function and increases recurrent stroke risk and mortality, making physical activity improvements an important target of intervention. We compared the effects of a highintensity walking intervention (FAST), a step activity monitoring behavioral intervention (SAM), or a combined intervention (FAST+SAM) on physical activity (i.e., steps per day). We hypothesized the combined intervention would yield the greatest increase in steps per day. Methods: This assessor-blinded multi-site randomized controlled trial was conducted at four university/hospital-based laboratories. Participants were 21-85 years old, walking without physical assistance following a single, unilateral non-cerebellar stroke of ≥6 months duration, and randomly assigned to FAST, SAM, or FAST+SAM for 12 weeks (2-3 sessions/week). FAST training consisted of walking-related activities for 40 minutes/session at 70-80% heart rate reserve, while SAM received daily feedback and goal-setting of walking activity (steps per day). Assessors and study statistician were masked to group assignment.The a priori-determined primary outcome and primary endpoint was change in steps per day from pre- to post-intervention. Adverse events (AEs) were tracked after randomization. All randomized participants were included in the intent-to-treat analysis.This study is registered at ClinicalTrials.gov, NCT02835313. Findings: Participants were enrolled from July 18, 2016-November 16, 2021. Of 250 randomized participants (mean[SE] age 63[0.80], 116F/134M), 89 were assigned to FAST, 81 to SAM, and 80 to FAST+SAM. Steps per day significantly increased in both the SAM (mean[SE] 1542[267], 95%CI:1014-2069, p<0.001) and FAST+SAM groups (1307[280], 752-1861, p<0.001), but not in the FAST group (406[238], 63-876, p=0.09). There were no deaths or serious study-related AEs and all other minor AEs were similar between groups. Interpretation: Only individuals with chronic stroke who completed a step activity monitoring behavioral intervention with skilled coaching and goal progression demonstrated improvements in physical activity (steps per day).

Effects of an Acute High Intensity Exercise Bout on Retention of Explicit, Strategic Locomotor Learning in Individuals With Chronic Stroke.

BACKGROUND: Exercise priming, pairing high intensity exercise with a motor learning task, improves retention of upper extremity tasks in individuals after stroke, but has shown no benefit to locomotor learning. This difference may relate to the type of learning studied. Upper extremity studies used explicit, strategic tasks; locomotor studies used implicit sensorimotor adaptation (split-belt treadmill). Since walking is an important rehabilitation goal, it is crucial to understand under which circumstances exercise priming may improve retention of a newly learned walking pattern. OBJECTIVE: Determine the impact of exercise priming on explicit, strategic locomotor learning task retention in chronic stroke survivors. METHODS: Chronic stroke survivors (>6 months) performed 2 treadmill walking sessions. Visual feedback was used to train increased step length. Participants were assigned to control group (no exercise), continuous exercise (5 minutes high intensity), or long-interval exercise (15 minutes high/moderate intervals). After day 1 learning, participants either rested or performed exercise. On day 2, retention of the learned walking pattern was tested. RESULTS: All groups learned on day 1 (P < .001). The 2 priming groups showed significant changes in blood lactate and heart rate after exercise priming, the resting control group did not (P < .001). On day 2, there was no significant between-group difference in cued or un-cued task retention (P = .963 and .287, respectively). CONCLUSIONS: Exercise priming did not affect retention of an explicit locomotor task in chronic stroke survivors. Further work should explore subgroups of individuals for whom priming may have selective clinical benefit to locomotor learning.ClinicalTrials.gov Identifier: NCT03726047.

Vascular determinants of hippocampal viscoelastic properties in healthy adults across the lifespan.

Arterial stiffness and cerebrovascular pulsatility are non-traditional risk factors of Alzheimer's disease. However, there is a gap in understanding the earliest mechanisms that link these vascular determinants to brain aging. Changes to mechanical tissue properties of the hippocampus (HC), a brain structure essential for memory encoding, may reflect the impact of vascular dysfunction on brain aging. We tested the hypothesis that arterial stiffness and cerebrovascular pulsatility are related to HC tissue properties in healthy adults across the lifespan. Twenty-five adults underwent measurements of brachial blood pressure (BP), large elastic artery stiffness, middle cerebral artery pulsatility index (MCAv PI), and magnetic resonance elastography (MRE), a sensitive measure of HC viscoelasticity. Individuals with higher carotid pulse pressure (PP) exhibited lower HC stiffness (ß = -0.39, r = -0.41, p = 0.05), independent of age and sex. Collectively, carotid PP and MCAv PI significantly explained a large portion of the total variance in HC stiffness (adjusted R2 = 0.41, p = 0.005) in the absence of associations with HC volumes. These cross-sectional findings suggest that the earliest reductions in HC tissue properties are associated with alterations in vascular function.

Impacts of Perceived Choice on Physical Strain, Emotional Stress and Health among Caregivers.

BACKGROUND: Having no choice in becoming a caregiver has been associated with higher levels of emotional stress and physical strain. This secondary analysis examined associations between caregivers' perceived choice and health outcomes. METHODS: This study utilized data from caregivers who answered a question about whether they felt they had a choice to take on caring for a care recipient in the Caregiving in the U.S. in 2020 survey. Variables of caregivers' and recipients' characteristics, caregiving activities, and health outcomes were extracted. Data were analyzed using descriptive statistics, t-tests, Chi-squared tests, and regression models. RESULTS: More than half of the 1,642 caregivers (54.4%) perceived no choice in becoming a caregiver. Having no choice was associated with higher levels of physical strain and emotional stress, and greater negative impact on caregiver's health. Other predictive variables of higher physical strain included being a primary caregiver, recipients having more comorbidities, and a higher level of care intensity. Higher education level, household income, number of recipient's conditions, level of care intensity, and being a primary caregiver were associated with higher levels of emotional stress. Taking care of a spouse and non-relative compared to taking care of a grandparent or parent was associated with lower emotional stress. Recipients with more comorbidities and higher care intensity were associated with worse caregiver health. CONCLUSIONS: There is a need to screen and identify caregivers who have no choice in caregiving and assist them in providing care for their recipient to prevent them from being invisible patients.

Adults with lower-limb amputation: Reduced multifidi muscle activity and extensor muscle endurance is associated with worse physical performance.

Trunk muscles may be an overlooked region of deficits following lower-limb amputation (LLA). This study sought to determine the extent that trunk muscle deficits are associated with physical function following amputation. Sedentary adults with a unilateral transtibial- (n = 25) or transfemoral-level (n = 14) amputation were recruited for this cross-sectional research study. Participants underwent a clinical examination that included ultrasound imaging of the lumbar multifidi muscles, the modified Biering-Sorensen Endurance Test (mBSET), and performance-based measures, that is, the Timed Up and Go (TUG), Berg Balance Scale (BBS), and 10-m Walk Test (10mWT). Associations between trunk muscle metrics and performance were explored with regression modeling, while considering covariates known to impact performance postamputation (p ≤ 0.100). Average ultrasound-obtained, lumbar multifidi activity was 14% and 16% for transfemoral- and transtibial-level amputations, respectively, while extensor endurance was 37.34 and 12.61 s, respectively. For TUG, nonamputated-side multifidi activity and an interaction term (level x non-amputated-side multifidi activity) explained 9.4% and 6.2% of the total variance, respectively. For 10mWT, beyond covariates, non-amputated-side multifidi activity and the interaction term explained 6.1% and 5.8% of the total variance, respectively. For TUG, extensor endurance and an interaction term (level x mBSET) explained 11.9% and 8.3% of the total variance beyond covariates; for BBS and 10mWT, extensor endurance explained 11.2% and 17.2% of the total variance, respectively. Findings highlight deficits in lumbar multifidi activity and extensor muscle endurance among sedentary adults with a LLA; reduced muscle activity and endurance may be important factors to target during rehabilitation to enhance mobility-related outcomes.

Construct validity of movement-evoked pain operational definitions in older adults with chronic low back pain.

OBJECTIVE: Movement-evoked pain (MeP) may predispose the geriatric chronic low back pain (LBP) population to health decline. As there are differing operational definitions for MeP, the question remains as to whether these different definitions have similar associations with health outcomes in older adults with chronic LBP. DESIGN: Cross-sectional analysis of an observational study. SETTING: Clinical research laboratory. SUBJECTS: 226 older adults with chronic LBP. METHODS: This secondary analysis used baseline data from a prospective cohort study (n = 250). LBP intensity was collected before and after the repeated chair rise test, stair climbing test, and 6-minute walk test; MeP change scores (ie, sum of pretest pain subtracted from posttest pain) and aggregated posttest pain (ie, sum of posttest pain) variables were calculated. LBP-related disability and self-efficacy were measured by the Quebec Back Pain Disability Scale (QBPDS) and Low Back Activity Confidence Scale (LOBACS), respectively. Physical function was measured with the Health ABC Performance Battery. Robust regression with HC3 standard errors was used to evaluate adjusted associations between both MeP variables and disability, self-efficacy, and physical function. RESULTS: Greater aggregated posttest MeP was independently associated with worse disability (b = 0.593, t = 2.913, P = .004), self-efficacy (b = -0.870, t = -3.110, P = .002), and physical function (b = -0.017, t = -2.007, P = .039). MeP change scores were not associated with any outcome (all P > .050). CONCLUSIONS: Aggregate posttest MeP was linked to poorer health outcomes in older adults with chronic LBP, but MeP change scores were not. Future studies should consider that the construct validity of MeP paradigms partially depends on the chosen operational definition.

Key Modifiable Factors in Community Participation Among Adults With Lower Limb Amputation.

OBJECTIVE: The aim of the study is to identify factors that may predict community participation among adults with lower limb amputation. DESIGN: This study is a secondary analysis of a cross-sectional data set, including 126 community-dwelling adults, ≥1 yr after unilateral transfemoral- ( n = 44; mean age = 59 ± 14 yrs) or transtibial-level amputation ( n = 82; mean age = 59 ± 14 yrs) seen in an outpatient limb loss clinic. Participation was assessed with the Community Integration Questionnaire. Factors, that is, demographics, comorbidities, prosthesis use per the Houghton Scale, Socket Comfort Score, assistive device use, falls history, and activity level per General Practice Physical Activity Questionnaire were evaluated. Moreover, balance confidence per the Activities-Specific Balance Confidence Scale, mobility per the Locomotor Capabilities Index, fast and self-selected gait speed per 10-meter walk tests, and functional mobility via Timed Up and Go were also included. RESULTS: Community participation was correlated with several factors ( P ≤ 0.050). Stepwise regression of correlated factors found absence of peripheral neuropathy and greater self-reported physical activity, balance confidence, and prosthesis use, as the strongest correlates, collectively explaining 50.1% of the variance in community participation post-lower limb amputation. CONCLUSIONS: Findings identify key modifiable factors for consideration in future prospective research seeking to enhance community reintegration and participation among adults living with a unilateral transfemoral- or transtibial-level amputation.

Clinically Relevant Subgroups Among Athletes Who Have Ruptured Their Anterior Cruciate Ligaments: A Delaware-Oslo Cohort Study.

OBJECTIVE: To identify subgroups of individuals with anterior cruciate ligament (ACL) injuries based on patient characteristics, self-reported outcomes, and functional performance at baseline, and to associate subgroups with long-term outcomes after ACL rupture. METHODS: A total of 293 participants (45.7% male, mean ± SD age 26.2 ± 9.4 years, days from injury 58 ± 35) were enrolled after effusion, pain, and range of motion impairments were resolved and quadriceps strength was at least 70% of the uninvolved limb. Mixture modeling was used to uncover latent subgroups without a prior group classification using probabilistic assignment. Variables include demographics, functional testing, and self-reported outcome measures. Radiographic evidence of osteoarthritis (OA; i.e., Kellgren/Lawrence grade of ≥1) in the involved knee at 5 years after injury was the primary outcome of interest. Chi-square tests assessed differences in the presence of radiographic OA in the involved knee between subgroups at 5 years after ACL rupture. Secondary outcomes of interest included radiographic OA in the uninvolved knee, return to preinjury sport by 2 years, operative status, and clinical OA (classified using Luyten et al criteria) at 5 years. RESULTS: Four distinct subgroups exist after ACL rupture (younger good self-report, younger poor self-report, older poor self-report, older good self-report) with 30%, 31%, 47%, and 53%, respectively, having involved knee OA. The percentage of radiographic OA was not significantly different between the groups (P = 0.059). CONCLUSION: The prevalence of OA in all subgroups is highly concerning. These results suggest there are unique subgroupings of individuals that may guide treatment after ACL rupture and reconstruction by providing support for developing a patient-centered approach.

Movement-Evoked Pain Versus Widespread Pain: A Longitudinal Comparison in Older Adults With Chronic Low Back Pain From the Delaware Spine Studies.

It is currently unknown which pain-related factors contribute to long-term disability and poorer perceived health among older adults with chronic low back pain (LBP). This investigation sought to examine the unique influence of movement-evoked pain (MeP) and widespread pain (WP) on longitudinal health outcomes (ie, gait speed, perceived disability, and self-efficacy) in 250 older adults with chronic LBP. MeP was elicited with 3 standardized functional tests, while presence of WP was derived from the McGill Pain Map. Robust regression with HC3 standard errors was used to examine associations between these baseline pain variables and health outcomes at 12-month follow-up. Covariates for these models included age, sex, body mass index, resting and recall LBP intensity, LBP duration, depression, pain catastrophizing, and baseline outcome (eg, baseline gait speed). Greater MeP was independently associated with worse 12-month LBP-related disability (b = .384, t = 2.013, P = .046) and poorer self-efficacy (b = -.562, t = -2.074, P = .039); but not gait speed (P > .05). In contrast, WP and resting and recall LBP intensity were not associated with any prospective health outcome after adjustment (all P > .05). Compared to WP and resting and recall LBP intensity, MeP is most strongly related to longitudinal health outcomes in older adults with chronic LBP. PERSPECTIVE: This article establishes novel independent associations between MeP and worse perceived disability and self-efficacy at 12-months in older adults with chronic LBP. MeP likely has biopsychosocial underpinnings and consequences and may therefore be an important determinant of health outcomes in LBP and other geriatric chronic pain populations.