Lower extremity kinematic coupling during single and double leg landing and gait in female junior athletes with dynamic knee valgus

Background Dynamic knee valgus (DKV) is a common lower extremity movement disorder among females. This study aimed to investigate kinematic couplings between lower extremity joints in female junior athletes with DKV during single and double-leg landing and gait. Methods Twenty-six physically active female junior athletes (10–14 years old) with DKV were recruited. Kinematic couplings between rearfoot, tibia, knee, and hip were extracted using eight Vicon motion capture cameras and two force plates. Zero-lag cross-correlation coefficient and vector coding were used to calculate kinematic couplings between joints during physical tasks. Paired t-test and Wilcoxon tests were run to find significant couplings between joint motions and coupling strengths. Bonferroni posthoc was used to determine significance with α ≤ 0.05. Results The results showed that the strongest kinematic relationship existed between rearfoot eversion/inversion and tibial internal/external rotation during all three tasks. Correlations of the rearfoot supination/pronation with tibial rotations, knee, and hip motions in sagittal, frontal, and transverse planes were very strong to strong during double-leg landing and moderate to weak during gait. A weak correlation was observed between rearfoot supination/pronation and hip adduction/abduction during single-leg landing. Conclusions Coupling relationships between rearfoot, knee, and hip vary by the task intensity and alignment profiles in female juniors with DKV.

Pathophysiology and classification of iliotibial friction injuries

As a result of the frequent endurance sports that are being practiced nowadays, many techniques have been introduced to this field with favorable outcomes regarding to the management approaches of the different injuries. However, no previous investigations have adequately discussed the pathophysiology of iliotibial band friction syndrome (ITBS) based on recent evidence from the current studies in the literature. In the present investigation, we have discussed the pathophysiology and related classification of iliotibial band friction injuries based on the current studies in the literature. The current evidence about the pathophysiology of the condition is still controversial, although epidemiological investigations indicate that ITBS is becoming a more prevalent condition among runners and other endurance athletes. Furthermore, many factors can attribute to the development of the condition and have been reported to take essential roles in the pathophysiology of the disease. Some of these factors include gender, iliotibial band tightness, rearfoot eversion and weak hip abductors. Further investigations are still needed to completely understand the pathophysiology of the disease to help clinicians aim to achieve better interventions to enhance the outcome of practicing endurance and excessive exercises.

Foot characteristics and mechanics in individuals with knee osteoarthritis: systematic review and meta-analysis

Background Foot characteristics and mechanics are hypothesized to affect aetiology of several lower extremity musculoskeletal conditions, including knee osteoarthritis (KOA). The purpose of this systematic review was to identify the foot characteristics and mechanics of individuals with KOA. Methods Five databases were searched to identify relevant studies on foot characteristics and mechanics in people with KOA. Meta-analyses were performed where common measures were found across included studies. Included studies were evaluated for data reporting quality using the STROBE (STrengthening the Reporting of OBservational studies in Epidemiology) checklist. Results Thirty-nine studies were included in this systematic review. Two studies reported participants with KOA had statistically significantly (P < 0.05) more pronated foot postures than those without. Meta-analyses for foot progression angle (FPA) and peak rearfoot eversion angle found no difference between those with and without KOA (FPA mean difference:-1.50 [95% confidence interval − 4.20-1.21]; peak rearfoot eversion mean difference: 0.71 [1.55–2.97]). Conclusion A more pronated foot posture was noticed in those with KOA. However, it was not possible to establish a relationship between other foot characteristics or mechanics in people with KOA due to heterogeneity between the included study and limited number of studies with similar measurements. There is need for identifying common measurement techniques and reporting metrics when studying the foot in those with KOA.

The effect of changing foot progression angle using real-time visual feedback on rearfoot eversion during running

Atypical rearfoot in/eversion may be an important risk factor for running-related injuries. Prominent interventions for atypical rearfoot eversion include foot orthoses, footwear, and taping but a modification derived from gait retraining to correct atypical rearfoot in/eversion is lacking. We aimed to investigate changes in rearfoot in/eversion, subtalar pronation, medial longitudinal arch angle, and selected lower limb joint biomechanics while performing toe-in/toe-out running using real-time visual feedback. Fifteen female runners participated in this study. Subjects performed toe-in/toe-out running using real-time visual feedback on foot progression angle, which was set ±5° from habitual foot progression angle. 3D kinematics of rearfoot in/eversion, subtalar supination/pronation, medial longitudinal arch angle, foot progression angle, hip flexion, ab/adduction and internal/external rotation, knee flexion, ankle dorsiflexion, and ankle power were analyzed. A repeated-measures ANOVA followed by pairwise comparisons was used to analyze changes between three conditions. Toe-in running compared to normal and toe-out running reduced peak rearfoot eversion (mean difference (MD) with normal = 2.1°; p<0.001, MD with toe-out = 3.5°; p<0.001), peak pronation (MD with normal = -2.0°; p<0.001, MD with toe-out = -3.4; p = <0.001), and peak medial longitudinal arch angle (MD with normal = -0.7°; p = 0.022, MD with toe-out = -0.9; p = 0.005). Toe-out running significantly increased these kinematic factors compared to normal and toe-in running. Toe-in running compared to normal running increased peak hip internal rotation (MD = 2.3; p<0.001), and reduced peak knee flexion (MD = 1.3; p = 0.014). Toe-out running compared to normal running reduced peak hip internal rotation (MD = 2.5; p<0.001), peak hip ab/adduction (MD = 2.5; p<0.001), peak knee flexion (MD = 1.5; p = 0.003), peak ankle dorsiflexion (MD = 1.6; p<0.001), and peak ankle power (MD = 1.3; p = 0.001). Runners were able to change their foot progression angle when receiving real-time visual feedback for foot progression angle. Toe-in/toe-out running altered rearfoot kinematics and medial longitudinal arch angle, therefore supporting the potential value of gait retraining focused on foot progression angle using real-time visual feedback when atypical rearfoot in/eversion needs to be modified. It should be considered that changes in foot progression angle when running is accompanied by changes in lower limb joint biomechanics.

The influence of design variations in footwear medial-lateral support on the running biomechanics of older female runners

Reports of greater incidence of knee pain and injury in older female runners compared with their younger counterparts may be associated with differences in lower limb biomechanics that influence knee joint loading. The aim of this study was to investigate footwear interventions aimed at influencing lower limb biomechanics in older female runners (>45 years). Strategies for reducing peak rearfoot eversion and the external knee adductor moment were investigated, since both measures have been associated with knee joint injury. Twenty female runners (mean age 50.7 ± 5.6 years) performed 10 running trials in four footwear conditions: neutral running shoe (Control); neutral shoe with 4° medial heel wedge insole (Medial Wedge); neutral shoe with 4° lateral heel wedge insole (Lateral Wedge); and neutral shoe with combined insole with 5° lateral wedge and medial arch support (Combined Insole). Peak rearfoot eversion and knee external adductor moment were compared for the four conditions using RMANOVA and post-hoc Tukey tests ( p < 0.05). Compared with the Control, peak rearfoot eversion was lower for the Combined Insole condition, with this value being lower than for all other insole conditions ( p < 0.05). Compared with the Control, the peak knee external adductor moment was lower for the Lateral Wedge and the Combined Insole conditions ( p < 0.05). These results support the use of a combined insole with lateral wedge and medial arch support for the reduction of peak rearfoot eversion and peak knee external adductor moment, variables that have been associated with increased risk of knee injury. If aiming to reduce knee external adductor moment alone, then the lateral wedge technology employed in this study provides an effective method for older female runners.

Performance on the Single-Legged Step Down and Running Mechanics

Context Previous authors have shown associations between kinematics on the single-legged step down (SLSD) and running mechanics. Therefore, the SLSD may be a useful tool for identifying runners with poor running mechanics when 2- or 3-dimensional gait analysis is not available. However, the associations between SLSD performance and running kinetics, as well as the influences of sex and muscle strength on these relationships, remain unclear. Objective To evaluate whether kinematics on the SLSD predict kinematics and kinetics while running and whether the relationships differ between men and women and are mediated by muscle strength. Design Cross-sectional study. Setting Biomechanics research laboratory. Patients or Other Participants Fifty highly trained runners (25 men, 25 women; age = 27.8 ± 9.2 years, height = 1.69 ± 0.26 m, mass = 66.3 ± 15.0 kg, running distance = 45.2 ± 19.1 mile/wk [72.32 ± 30.56 km/wk]). Main Outcome Measure(s) Relationships between kinematics on the SLSD and kinematics and kinetics during running were evaluated. We also assessed whether muscle strength moderated these relationships. Results For men, linear regression revealed that peak hip adduction (R2 = 0.306, P = .012), internal rotation (R2 = 0.439, P = .002), knee valgus (R2 = 0.544, P = .001), and rearfoot eversion (R2 = 0.274, P = .008) on the SLSD were strongly predictive of kinematics during running. In women, only peak hip internal rotation (R2 = 0.573, P = .001), knee valgus (R2 = 0.442, P = .001), and rearfoot eversion (R2 = 0.384, P = .012) predicted running kinematics. In women, total medial collapse on the SLSD predicted peak hip-adductor moment (R2 = 0.364, P = .001) during running. None of the relationships were moderated by muscle strength in either men or women. Conclusions Kinematics during the SLSD predicted kinematics while running in both men and women but only predicted kinetics while running in women. Given that none of the relationships between SLSD performance and running mechanics were moderated by muscle strength, clinicians should assess movement quality and strength independently.

Rearfoot and Tibial Motion during Gait Associated with Medial Tibial Stress Syndrome: A Systematic Review

PURPOSE: The purpose of this study was to confirm the kinematic characteristics of overuse leg injuries during gait through a systematic review.METHODS: Electronic databases from 1960 to 2018 were used to search studies. Physiotherapy Evidence Database Scale was used for quality of studies. Effect sizes (ES) of between-groups and its 95% confidence intervals were calculated.RESULTS: Seven studies were selected for review. The average Physiotherapy Evidence Database Scale score was 4.3 of 10-point scale. The ES for maximum rearfoot eversion from 5 studies ranged from -0.34 to 0.67 with 3 of 5 studies statistically significant. The ES of eversion excursion from 4 studies ranged from -0.24 to 2.37 and 3 of 4 studies showed statistically significant. The ES of maximum eversion velocity ranged from 0.29 to 0.38 from all of 2 studies. With abduction, the ES for abduction excursion ranged from -0.04 to 0.35, and 2 of 3 studies revealed statistically significant. The ES of maximum abduction velocity showed statistically significant with the ES of 0.23 and 0.61. However, maximum abduction from 3 studies showed non-significant with ES ranges from 0.00 to 0.62.CONCLUSIONS: The rearfoot motion (eversion) associates with overuse leg injuries during gait more than tibial motion (internal rotation).

Rearfoot and Tibial Motion during Gait Associated with Medial Tibial Stress Syndrome: A Systematic Review

PURPOSE: The purpose of this study was to confirm the kinematic characteristics of overuse leg injuries during gait through a systematic review.METHODS: Electronic databases from 1960 to 2018 were used to search studies. Physiotherapy Evidence Database Scale was used for quality of studies. Effect sizes (ES) of between-groups and its 95% confidence intervals were calculated.RESULTS: Seven studies were selected for review. The average Physiotherapy Evidence Database Scale score was 4.3 of 10-point scale. The ES for maximum rearfoot eversion from 5 studies ranged from -0.34 to 0.67 with 3 of 5 studies statistically significant. The ES of eversion excursion from 4 studies ranged from -0.24 to 2.37 and 3 of 4 studies showed statistically significant. The ES of maximum eversion velocity ranged from 0.29 to 0.38 from all of 2 studies. With abduction, the ES for abduction excursion ranged from -0.04 to 0.35, and 2 of 3 studies revealed statistically significant. The ES of maximum abduction velocity showed statistically significant with the ES of 0.23 and 0.61. However, maximum abduction from 3 studies showed non-significant with ES ranges from 0.00 to 0.62.CONCLUSIONS: The rearfoot motion (eversion) associates with overuse leg injuries during gait more than tibial motion (internal rotation).