Effect of Footwear Type on Biomechanical Risk Factors for Knee Osteoarthritis.

Background: Regular walking in different types of footwear may increase the mediolateral shear force, knee adduction moment, or vertical ground-reaction forces that could increase the risk of early development of knee osteoarthritis (OA). Purpose: To compare kinematic and kinetic parameters that could affect the development of knee OA in 3 footwear conditions. Study Design: Controlled laboratory study. Methods: A total of 40 asymptomatic participants performed walking trials in the laboratory at self-selected walking speeds under barefoot (BF), minimalistic (MF), and neutral (NF) footwear conditions. Knee joint parameters were described using discrete point values, and continuous curves were evaluated using statistical parametric mapping. A 3 × 1 repeated-measures analysis of variance was used to determine the main effect of footwear for both discrete and continuous data. To compare differences between footwear conditions, a post hoc paired t test was used. Results: Discrete point analyses showed a significantly greater knee power in NF compared with MF and BF in the weight absorption phase (P < .001 for both). Statistical parametric mapping analysis indicated a significantly greater knee angle in the sagittal plane at the end of the propulsive phase in BF compared with NF and MF (P = .043). Knee joint moment was significantly greater in the propulsive phase for the sagittal (P = .038) and frontal planes (P = .035) in BF compared with NF and MF and in the absorption phase in the sagittal plane (P = .034) in BF compared with MF and NF. A significant main effect of footwear was found for anteroposterior (propulsion, ↑MF, NF, ↓BF [P = .008]; absorption, ↑BF, MF, ↓NF [P = .001]), mediolateral (propulsion, ↑MF, NF, ↓BF [P = .005]; absorption, ↑NF, MF, ↓BF [P = .044]), and vertical (propulsion, ↑NF, BF, ↓MF [P = .001]; absorption, ↑MF, BF, ↓NF [P < .001]) ground-reaction forces. Knee power showed a significant main effect of footwear (absorption, ↑NF, MF, ↓BF [P = .015]; propulsion, ↑MF, NF, ↓BF [P = .039]). Conclusion: Walking in MF without sufficient accommodation affected kinetic and kinematic parameters and could increase the risk of early development of knee OA.

Comparison of spatiotemporal gait parameters and their variability in typically developing children aged 2, 3, and 6 years.

Independent walking is an important milestone in a child's development. The maturation of central nervous system, changes in body proportions, spatiotemporal parameters of gait and their variability change are dependent on age. The first aim of this study was to compare non-normalized and normalized spatiotemporal parameters and their variability in children. The second aim was to determine which spatiotemporal parameters are most affected by aging. Data from 64 typically developing children (age: 2.0-6.9 years), who walked at a self-selected speed along a 10m walkway, were collected with a motion capture system. Spatiotemporal parameters were normalized based on leg length. The main effect of the non-normalized walking speed revealed a moderate effect size (ES = 0.72) comparing 2- and 3-years-old, a large effect size comparing 2- and 6-years-old (ES = 1.77), and a large ES comparing 3- and 6-years-old (ES = 1.22). The normalized stride width parameter showed a statistically significant difference with large effect size between 2 vs 3 (ES = 1.00), 2 vs 6 (ES = 3.17), and 3 vs 6 (ES = 1.96). A statistically significant decrease in intra-individual gait variability with increasing age was observed in all parameters except for stride width. The variability of stride width may serve as a parameter in 2-year-olds to assess deviations from typically developing children. The assessment of effect size could be a useful indicator for clinical practice.

Effect of transtibial prosthesis weight on the contralateral knee joint in relation to the risk of osteoarthritis.

BACKGROUND: Individuals with transtibial amputation place more load on the contralateral lower extremity. A higher adduction moment at the knee joint has been shown to have an effect on the risk of osteoarthritis. OBJECTIVE: The aim of this study was to investigate the effect of weight-bearing of lower-limb prosthesis on the biomechanical parameters associated with the risk of contralateral knee osteoarthritis. STUDY DESIGN: Cross-sectional. METHODS: The experimental group of 14 subjects with unilateral transtibial amputation (13 males). The mean age was 52.7 ± 14.2 years, height 175.6 ± 6.3 cm, weight 82.3 ± 12.5 kg, and duration of prosthesis use 16.5 ± 9.1 years. The control group consisted of 14 healthy subjects with identical anthropometric parameters. Dual emission X-ray absorptiometry was used to determine the weight of the amputated limb. For gait analysis, 10 Qualisys infrared cameras and a motion sensing system on 3 Kistler force platforms were used. Gait was analyzed with the original, lighter, commonly used prosthesis, as well as the prosthesis loaded to the original limb weight. RESULTS: The gait cycle and kinetic parameters of the amputated and healthy limbs were more similar to those of the control group when using the weighted prosthesis. CONCLUSIONS: We recommend further research to more accurately specify the weight of the lower-limb prosthesis with respect to the prosthesis design and duration of use of the heavier prosthesis during the day.

The effect of athletic throwing events on the body composition and bone density in the limbs of throwing athletes.

BACKGROUND: Throwing and putting are technical athletic events where one upper limb is dominant. The different load on the preferred and non-preferred limb may influence the body composition of the upper limb segments. The objective of the study is to assess the difference between the throwing and non-throwing upper limb in athletes specializing in javelin throw and shot put based on the segmental body composition analysis and kinetic analysis. METHODS: The group included 16 throwers at the age of 17.5±2.4 years. As a control group, we used 16 jumper athletes (age of 17.7±2.6 years). The symmetry of the load on upper limbs during a push-up was provided by the kinetic motion analysis. The segmental analysis of the upper limb body composition parameters was implemented using the method of dual X-ray absorptiometry. RESULTS: As to the power parameters, symmetry between the throwing and non-throwing upper limbs during the performance of a push-up was observed. The analysis of the upper limb body mass distribution showed statistically and objective significance in the bone mass values. The ratio of bone mass was higher in the throwing upper limb by 0.02 kg (P<0.0001) and bone density was higher by 0.07 g/cm2 (P<0.0001), the practical significance of the differences was major change for BMC (d=0.8) and medium for BMD (d=0.5). CONCLUSIONS: The results imply that the throw is a significant factor that contributes to the formation of bone mass.

Running and Physical Activity in an Air-Polluted Environment: The Biomechanical and Musculoskeletal Protocol for a Prospective Cohort Study 4HAIE (Healthy Aging in Industrial Environment-Program 4).

Far too little attention has been paid to health effects of air pollution and physical (in)activity on musculoskeletal health. The purpose of the Healthy aging in industrial environment study (4HAIE) is to investigate the potential impact of physical activity in highly polluted air on musculoskeletal health. A total of 1500 active runners and inactive controls aged 18-65 will be recruited. The sample will be recruited using quota sampling based on location (the most air-polluted region in EU and a control region), age, sex, and activity status. Participants will complete online questionnaires and undergo a two-day baseline laboratory assessment, including biomechanical, physiological, psychological testing, and magnetic resonance imaging. Throughout one-year, physical activity data will be collected through Fitbit monitors, along with data regarding the incidence of injuries, air pollution, psychological factors, and behavior collected through a custom developed mobile application. Herein, we introduce a biomechanical and musculoskeletal protocol to investigate musculoskeletal and neuro-mechanical health in this 4HAIE cohort, including a design for controlling for physiological and psychological injury factors. In the current ongoing project, we hypothesize that there will be interactions of environmental, biomechanical, physiological, and psychosocial variables and that these interactions will cause musculoskeletal diseases/protection.