Biomechanical Threshold Values for Identifying Clinically Significant Knee-Related Symptoms Six Months Following Anterior Cruciate Ligament Reconstruction.

CONTEXT: Slower habitual walking speed and aberrant gait biomechanics are linked to clinically significant knee-related symptoms and articular cartilage composition changes linked to posttraumatic osteoarthritis (PTOA) following anterior cruciate ligament reconstruction (ACLR). OBJECTIVE: To determine specific gait biomechanical variables that can accurately identify individuals with clinically significant knee-related symptoms post-ACLR, and the corresponding threshold values, sensitivity, specificity, and odds ratios for each biomechanical variable. DESIGN: Cross-sectional analysis. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Seventy-one individuals (n=38 female; age=21±4 years; height=1.76±0.11 m; mass=75.38±13.79 kg) who were 6 months post-primary unilateral ACLR (6.2±0.4 months). MAIN OUTCOME MEASURES: 3D motion capture of 5 overground walking trials was used to calculate discrete gait biomechanical variables of interest during stance phase (1st and 2nd peak vertical ground reaction force [vGRF]; midstance minimum vGRF; peak internal knee abduction and extension moments; and peak knee flexion angle), along with habitual walking speed. Knee Injury and Osteoarthritis Outcome Scores (KOOS) was used to dichotomize patients as symptomatic (n=51) or asymptomatic (n=20) using the Englund et al. 2003 KOOS guidelines for defining clinically significant knee-related symptoms. Separate receiver operating characteristic (ROC) curves and respective areas under the curve (AUC) were used to evaluate the capability of each biomechanical variable of interest for identifying individuals with clinically significant knee-related symptoms. RESULTS: Habitual walking speed (AUC=0.66), vGRF at midstance (AUC=0.69), and 2nd peak vGRF (AUC=0.76), demonstrated low-to-moderate accuracy for identifying individuals with clinically significant knee-related symptoms. Individuals who exhibited habitual walking speeds ≤1.27 m/s, midstance vGRF ≥0.82 BW, and 2nd peak vGRF ≤1.11 BW, demonstrated 3.13, 6.36, and 9.57 times higher odds of experiencing clinically significant knee-related symptoms, respectively. CONCLUSIONS: Critical thresholds for gait variables may be utilized to identify individuals with increased odds of clinically significant knee-related symptoms and potential targets for future interventions.

Early Gait Biomechanics Linked to Daily Steps Following Anterior Cruciate Ligament Reconstruction.

CONTEXT: Gait biomechanics and daily steps are important aspects of knee joint loading that change following anterior cruciate ligament reconstruction (ACLR). Understanding their relationship during the first 6 months post-ACLR could help develop comprehensive rehabilitation interventions that promote optimal joint loading following injury, thereby improving long-term knee joint health. OBJECTIVE: Our primary objective was to compare biomechanical gait waveforms throughout stance at early timepoints post-ACLR in individuals with different daily step behaviors at 6 months post-ACLR. The secondary aim was to examine how these gait waveforms compare to those of uninjured controls. DESIGN: Case-Control Study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Individuals with primary ACLR assigned to a low (LSG) (n=13) or high step group (HSG) (n=19) based on their average daily steps at 6 months post- ACLR, and uninjured matched controls (n=32). MAIN OUTCOME MEASURE(S): Gait biomechanics were collected at 2, 4, and 6 months post-ACLR in ACLR individuals and at a single session for controls. Knee adduction moment (KAM), knee extension moment (KEM), and knee flexion angle (KFA) waveforms were calculated during gait stance and then compared via functional waveform analyses. Mean differences and corresponding 95% confident intervals between groups were reported. RESULTS: Primary results demonstrated lesser KFA (1-45%, 79-92% of stance) and greater KEM (65-93% of stance) at 2 months and greater KAM (14-20%, 68-92% of stance) at 4 months post-ACLR for the HSG compared to the LSG. KEM, KAM, and KFA waveforms differed across various proportions of stance at all timepoints between step groups and controls. CONCLUSION: Differences in gait biomechanics are present at 2 and 4 months post-ACLR between step groups, with the LSG demonstrating an overall more flexed knee and more profound stepwise underloading throughout stance than the HSG. The results indicate a relation between early gait biomechanics and later daily steps behaviors following ACLR.

Acutely Normalizing Walking Speed Does Not Normalize Gait Biomechanics Post-Anterior Cruciate Ligament Reconstruction.

PURPOSE: To determine the effect of acutely increasing walking speed on gait biomechanics in ACLR individuals compared with their habitual speed and uninjured matched-controls. METHODS: Gait biomechanics were collected on 30 ACLR individuals (20 females; age, 22.0 ± 4.2 yr; body mass index, 24.0 ± 3.0 kg·m -2 ) at their habitual speed and at 1.3 m·s -1 , a speed similar to controls, and 30 uninjured matched-controls (age: 21.9 ± 3.8, body mass index: 23.6 ± 2.5) at their habitual speed. Functional waveform analyses compared biomechanics between: i) walking at habitual speed vs 1.3 m·s -1 in ACLR individuals; and ii) ACLR individuals at 1.3 m·s -1 vs controls. RESULTS: In the ACLR group, there were no statistically significant biomechanical differences between walking at habitual speed (1.18 ± 0.12 m·s -1 ) and 1.3 m·s -1 (1.29 ± 0.05 m·s -1 ). Compared with controls (habitual speed: 1.34 ± 0.12 m·s -1 ), the ACLR group while walking at 1.3 m·s -1 exhibited smaller vertical ground reaction force (vGRF) during early and late stance (13-28, 78-90% stance phase), greater midstance vGRF (47-61%), smaller early-to-midstance knee flexion angle (KFA; 1-44%), greater mid-to-late stance KFA (68-73, 96-101%), greater internal knee abduction moment (69-101%), and smaller internal knee extension moment (4-51, 88-96%). CONCLUSIONS: Increasing walking speed to a speed similar to uninjured controls did not elicit significant changes to gait biomechanics, and ACLR individuals continued to demonstrate biomechanical profiles that are associated with PTOA development and differ from controls.

Evidence-Based Dietary Practices to Improve Osteoarthritis Symptoms: An Umbrella Review.

While there is some research investigating whole foods or diets that are easily understood and accessible to patients with osteoarthritis, specific nutrients or nutraceuticals are more commonly identified. Unfortunately, guidelines and evidence surrounding individual nutrients, extracts, and nutraceuticals are conflicting and are more difficult to interpret and implement for patients with osteoarthritis. The purpose of this umbrella review is to provide a comprehensive understanding of the existing evidence of whole foods and dietary patterns effects on osteoarthritis-related outcomes to inform evidence-based recommendations for healthcare professionals and identify areas where more research is warranted. A literature search identified relevant systematic reviews/meta-analyses using five databases from inception to May 2022. Five systematic reviews/meta-analyses were included in the current umbrella review. Most evidence supported the Mediterranean diet improving osteoarthritis-related outcomes (e.g., pain, stiffness, inflammation, biomarkers of cartilage degeneration). There was little to no evidence supporting the effects of fruits and herbs on osteoarthritis-related outcomes; however, there was some suggestion that specific foods could potentiate symptom improvement through antioxidative mechanisms. The overall lack of homogeneity between the studies limits the conclusions that can be made and highlights the need for quality research that can identify consumer-accessible foods to improve osteoarthritis-related symptoms.

Let's go! The impact of mobile laboratory technology on STEM accessibility during National Biomechanics Day.

National Biomechanics Day continues to expose thousands of youth to the biomechanics discipline each year. As part of the 2022 events, Seattle University used its Kinesiology Mobile Lab to host multiple National Biomechanics Day events across Washington state, engaging over 600 youth in a one-month period. This case study in hands-on experiential learning highlights the use of on-site demonstrations to increase accessibility to STEM education and educational resources.

Body mass affects kinetic symmetry and inflammatory markers in adolescent knees during gait.

BACKGROUND: Early-onset osteoarthritis has been attributed to pro-inflammatory factors and biomechanical changes in obesity. However, research has yet to explore whether knee joint moments are asymmetrical in children with obesity and could precede the onset of knee osteoarthritis. The present study compares knee moment asymmetry between adolescents with and without obesity and examines the relationship between asymmetries and inflammatory biomarkers. METHODS: Twenty-eight adolescents (13-16 years) were classified as with (n = 12) or without (n = 16) obesity. Lower extremity kinetics were measured using three-dimensional motion analysis. Bilateral knee joint moments were analyzed in the sagittal, frontal, and transverse planes across stance phase. Kinetic asymmetry was calculated between the right and left sides and represented by the R2 value. Enzyme-linked immunosorbent assays analyzed serum 25-hydroxy vitamin D, interferon gamma, tumor nercrosis factor alpha, interleukin-6, and C-reactive protein levels. Parametric and non-parametric tests determined significant group differences in asymmetries and biomarkers, respectively. Spearman's correlations identified relationships between biomarkers and asymmetries with statistically significant group differences. FINDINGS: Adolescents with obesity had greater sagittal (loading, midstance) and frontal (midstance, pre-swing) plane kinetic knee asymmetry and higher concentrations of interleukin-6 and C-reactive protein. A moderately negative correlation existed between C-reactive protein and sagittal (loading, midstance) plane asymmetry, and also between interleukin-6 and frontal (pre-swing) plane asymmetry. INTERPRETATION: Inflammatory response increases with greater knee joint asymmetry, suggesting knee joint damage and altered joint loading co-exist in adolescents with obesity. Increased risk to joint health may exist in sub-phases where knee joints are improperly loaded.

Mind the Gap: Exploring Nutritional Health Compared With Weight Management Interests of Individuals with Osteoarthritis.

Background: For persons with osteoarthritis (OA), nutrition education may facilitate weight and OA symptom management. Objectives: The primary aim of this study was to determine preferred OA-related nutritional and weight management topics and their preferred delivery modality. The secondary aim was to determine whether there is a disconnect between what patients want to know about nutrition and OA management and what information health-care professionals (HCPs) are providing to patients. Methods: The Osteoarthritis Action Alliance surveyed individuals with OA to identify their preferences, categorized in 4 domains: 1) strategies for weight management and a healthy lifestyle; 2) vitamins, minerals, and other supplements; 3) foods or nutrients that may reduce inflammation; and 4) diets for weight loss. HCPs were provided these domains and asked which topics they discussed with patients with OA. Both groups were asked to select currently utilized or preferred formats of nutritional resources. Results: Survey responses from 338 individuals with OA and 104 HCPs were included. The highest preference rankings in each domain were: 1) foods that make OA symptoms worse (65%), foods and nutrients to reduce inflammation (57%), and healthy weight loss (42%); 2) glucosamine (53%), vitamin D (49%), and omega-3 fatty acids (45%); 3) spices and herbs (65%), fruits and vegetables (58%), and nuts (40%); and 4) Mediterranean diet (21%), low-carbohydrate diet (18%), and fasting or intermittent fasting (15%). There was greater than 20% discrepancy between interests reported by individuals with OA and discussions reported by HCPs on: weight loss strategies, general information on vitamins and minerals, special dietary considerations for other conditions, mindful eating, controlling caloric intake or portion sizes, and what foods worsen OA symptoms. Most respondents preferred to receive nutrition information in a passive format and did not want information from social media messaging. Conclusions: There is disparity between the nutrition education content preferred by individuals with OA (which often lacks empirical support) and evidence-based topics being discussed by HCPs. HCPs must communicate evidence-based management of joint health and OA symptoms in patient-preferred formats. This study explored the information gap between what individuals with OA want to know and what HCPs believe they need to know.