UNASSIGNED: It is widely reported that the weight distribution in each foot is approximately 60% in the rearfoot and 40% in the forefoot. For balance training, it is recommended to transfer some weight to the forefoot. However, it is still unclear whether fore-rear foot weightbearing ratio affects balance and plantar pressure parameters.
UNASSIGNED: There is a relationship between the forefoot weightbearing ratio and balance and plantar pressure in female adolescent athletes.
UNASSIGNED: Cross-sectional study.
UNASSIGNED: Level 3.
UNASSIGNED: A total of 91 adolescent female athletes aged between 10 and 19 years were included in the study. Weightbearing ratios of the forefoot, balance, and plantar pressure were assessed using a plantar pressure platform (FootWork, AMCube IST). In the static and stabilometric evaluation, the weightbearing ratio (%), mean and maximum plantar pressure (kPa), center of pressure (CoP) total, antero-posterior and medio-lateral sway length (cm), CoP surface area (cm2), and length over area (cm-1) were recorded. In the dynamic evaluation, the maximum pressure (kPa) acting on each foot was recorded.
UNASSIGNED: Two groups with forefoot weightbearing ratio <40% and ≥40% were compared. Maximum pressure values in static conditions, CoP anteroposterior, and total sway length were significantly different between these groups. In addition, as the amount of load transferred to the forefoot increased, CoP total and anteroposterior sway length increased postural stability.
UNASSIGNED: Although postural control mechanisms are quite complex, plantar pressure and postural control parameters can be varied by optimizing rear-to-fore foot weight transfer.
UNASSIGNED: This study will contribute to the development of appropriate training and rehabilitation strategies to optimize athlete performance and reduce injury risk.

BACKGROUND: Hindfoot varus deformity is common in people with unilateral upper motor neuron syndrome (UMNS) and can be dynamic or persistent. The aims of this study were (1) to gain insight into plantar pressure characteristics of people with chronic UMNS in relation to hindfoot varus and (2) to propose a quantitative outcome measure, based on plantar pressure, for the scientific evaluation of surgical interventions.
METHODS: In this retrospective study, a cohort comprising plantar pressure data of 49 people with UMNS (22 \"no hindfoot varus\", 18 \"dynamic hindfoot varus\", and 9 \"persistent hindfoot varus\"), and 586 healthy controls was analyzed. As an indication of plantigrade foot contact, the ratio between the plantar contact area of the affected and the non-affected foot was calculated. To investigate spatial and temporal aspects of plantar pressure, normalized plantar pressure patterns and center of pressure trajectories were computed.
RESULTS: People with UMNS had lower plantar pressure area ratios compared to healthy controls. Additionally, increased plantar pressure underneath the lateral foot was found in people with a persistent hindfoot varus. Center of pressure trajectories were more lateral during the first 26% of the stance phase in people with a dynamic hindfoot varus and during the first 82% of the stance phase in people with a persistent hindfoot varus compared to healthy controls.
CONCLUSIONS: Spatial and temporal differences in plantar pressure were found in people with dynamic or persistent hindfoot varus deformity. We propose to primarily use the medio-lateral center of pressure trajectory as outcome measure for the scientific evaluation of surgical interventions targeting hindfoot varus.

UNASSIGNED: Asymmetric gait patterns are mostly observed in hemiplegic stroke patients. These abnormal gait patterns resulting in abnormal speed, and decreased ability in daily of activity living.
UNASSIGNED: This study aimed to determine the immediate changes in gait parameters and plantar pressure during elevation by wearing an insole on the sound side lower extremity of patients with hemiplegia.
UNASSIGNED: Thirty-six participants were recruited, comprising those with a post-stroke follow-up of ≥3 months and a functional ambulation category score of ≥2. The participants were asked to walk with and without a 1 cm insole in the shoe of their sound side, and the order of wearing or not wearing the insole was randomized. Gait parameters, bilateral gait parameters, and dynamic plantar pressure were measured using the GAITRite Walkway System.
UNASSIGNED: Paired t-test was used to examine immediate changes in gait parameters and plantar pressure with and without insoles during walking in the same group. Overall, gait velocity and step length significantly decreased (p < 0.05), whereas step time significantly increased (p < 0.05). The swing phase of the affected sidelower extremities significantly increased (p < 0.05), and the stance phase significantly decreased (p < 0.05). Double-support unloading phase (pre-swing phase) significantly increased (p < 0.05). The changes in plantar pressure were significantly increased in some lateral zones and significantly decreased in the medial zone of the mid-hindfoot, both in terms of pressure per time and peak pressure (p < 0.05).
UNASSIGNED: Although this study did not show immediate positive effects on gait parameters and gait cycle, it is expected that sensory input from the sole of the foot through changes in plantar pressure may help improve gait asymmetry and regulate postural symmetry.

Background/Objectives: Studies have reported that patients suffering from ankylosing spondylitis (AS) have decreased postural stability in comparison to healthy subjects. Our study aims to compare static plantar pressure and stabilometry parameters in AS patients who performed an 8-week exercise program (spine motion and flexibility exercises; stretching of hamstring, erector spine, and shoulder muscles; control abdominal and diaphragm breathing exercises and chest expansion exercises), in three different testing conditions (eyes open, eyes closed, and head retroflexed). Methods: Plantar pressure (the loading of the first and fifth metatarsal heads (MT1, MT5) and calcaneus) and stabilometry (CoP path length, 90% confidence ellipse area, and maximum CoP speed) were recorded in 28 AS patients (age 56.64 ± 10.3 years; body mass index 29.4 ± 4.9 kg/m2) at the beginning of rehabilitation and after 8 weeks. At first evaluation, there were significant differences (p < 0.05) for the foot loading sites (MT1, MT5, and calcaneus), both for the right and left feet, when comparing eyes open with the other two testing situations. Results: After rehabilitation, significant differences were recorded between eyes-open and head-retroflexed conditions for MT1 (p = 0.03 for right; p = 0.004 for left) and calcaneus (p = 0.014 for right; p = 0.011 for left). A significantly higher CoP path length was registered in both initial and final assessments when tested with eyes closed. The maximum CoP speed had increased values at both evaluations when tested with head retroflexed. Conclusions: The CoP path length decreased after the physical exercise program, with a better postural stability after rehabilitation.

UNASSIGNED: This study aims to investigate the plantar biomechanics of healthy young males as they descend a single transition step from varying heights.
UNASSIGNED: Thirty healthy young males participated the experiment using the F-scan insole plantar pressure system in which participants made single transition steps descent from four step heights (5, 15, 25, and 35 cm), leading with their dominant or non-dominant foot. Plantar pressure data were collected for 5 s during the period between landing touchdown and standing on the ground. Landing at each step height was repeated three times, with a five-minute rest between different height trials.
UNASSIGNED: At 5 cm and 15 cm steps, participants demonstrated a rearfoot landing strategy on both sides. However, forefoot contact was observed at heights of 25 cm and 35 cm. Parameters related to center of plantar pressure (COP) of the leading foot were significantly larger compared to the trailing foot (P < 0.001), increased with higher step heights. Vertical ground reaction forces for the biped, leading and trailing feet decreased with increasing step height (all P < 0.05). The leading foot had a higher proportion of overall and forefoot loads, and a lower proportion of rearfoot load compared to the trailing foot (P < 0.001). The overall load on the dominant side was lower than that on the non-dominant side for both the leading and trailing feet (P < 0.001). For the trailing foot, forefoot load on the dominant side was lower than that on the non-dominant side, however, the opposite result appeared in rearfoot load (P < 0.001). Upon the leading foot landing, forefoot load exceeded the rearfoot load for the dominant (P < 0.001) and non-dominant sides (P < 0.001). Upon the trailing foot landing, forefoot load was lower than the rearfoot load for the dominant (P < 0.001) and non-dominant sides (P = 0.019).
UNASSIGNED: When the characteristics of biomechanical stability are compromised by step height, landing foot, and footedness factors - due to altered foot landing strategies, changing COP, or uneven force distribution - ability to control motion efficiently and respond adaptively to the forces experienced during movement is challenged, increasing the likelihood of loss of dynamic balance, with a consequent increased risk of ankle sprains and falls.

The aim of the study was to measure and compare plantar pressures, forces and gait parameters in athletes with and without hallux valgus. It was a cross sectional study with the sample Size: 106 [53 for each group (Hallux valgus and without hallux valgus)]. Hallux valgus angle was calculated with digital photographs uploaded on Karasunpo software. Participants only with the moderate and severe hallux valgus angle were selected. For participant having hallux valgus in both the feet, one with the greater angle of hallux valgus was selected. Participants without hallux valgus were the ones whose hallux valgus angle was less than 15 degrees. The participants of both groups were asked to walk on predetermined speed of 4.8 kmph. The device used was Zebris FDM-T (Zebris® Medical GmbH, Germany) for the pedobarographic and gait parameter measurement. On an average, measurement was recorded for 20 steps during the different phases of gait in all subjects and corresponding mean values were calculated. Mean values for all the readings were documented and statistically calculated. Statistical analysis was done using SPSS (v.27.0.1) with unpaired t-test to compare between both the groups. Shapiro-Wilk test was used to check normality of data. Significant p-values for forefoot forces (0.001), forefoot pressures (<0.001) and midfoot pressures (0.002) were found. There is clear evidence of increased foot loading in young adult athletes with hallux valgus on the forefoot and midfoot regions while performing activities.

OBJECTIVE: To investigate the contribution of foot type to plantar pressures in a community-dwelling adult population with type 2 diabetes.
METHODS: Foot Posture Index-6 (FPI-6) as a measure of foot type, barefoot plantar pressure (peak pressures and pressure-time integrals), presence of forefoot deformities, peripheral neuropathy, ankle and first metatarsophalangeal joint (MTPJ) dorsiflexion range of motion (ROM), and demographic variables were measured. Standard multiple regression models were used to investigate the independent contribution of FPI-6 on plantar pressure variables at the hallux, forefoot, and rearfoot.
RESULTS: 122 adults (mean age 70.9 ± 9.3, n = 58 female) with type 2 diabetes were recruited. A lower (more supinated) FPI-6 significantly contributed to an increased forefoot pressure-time integral (β = -0.285, p = 0.04). FPI-6 was not a statistically significant independent predictor of peak pressure at the hallux, forefoot or rearfoot.
CONCLUSIONS: When screening for at-risk sites of elevated plantar pressure in adults with type 2 diabetes, clinicians should consider performing the FPI-6 along with other clinical measures that have been shown to be associated with increased plantar pressures including first MTPJ dorsiflexion ROM, and presence of digital deformities. Evidence-based treatments to offload these areas should then be considered.

OBJECTIVE: To investigate relationships between static foot posture, dynamic plantar foot forces and knee pain in people with medial knee osteoarthritis (OA).
METHODS: Data from 164 participants with symptomatic, moderate to severe radiographic medial knee OA were analysed. Knee pain was self-reported using a numerical rating scale (NRS; scores 0-10; higher scores worse) and the Knee Injury and Osteoarthritis Outcome Score pain subscale (KOOS; scores 0-100; lower scores worse). Static foot posture was assessed using clinical tests (foot posture index, foot mobility magnitude, navicular drop). Dynamic plantar foot forces (lateral, medial, whole foot, medial-lateral ratio, arch index) were measured using an in-shoe plantar pressure system while walking. Relationships between foot posture and plantar forces (independent variables) and pain (dependent variables) were evaluated using linear regression models, unadjusted and adjusted for sex, walking speed, Kellgren & Lawrence grade, shoe category, and body mass (for dynamic plantar foot forces).
RESULTS: No measure of static foot posture was associated with any knee pain measure. Higher medial-lateral foot force ratio at midstance, and a higher arch index during overall stance, were weakly associated with higher knee pain on the NRS (regression coefficient = 0.69, 95% confidence interval (CI) 0.09 to 1.28) and KOOS (coefficient=3.03, 95% CI 0.71 to 5.35) pain scales, respectively.
CONCLUSIONS: Dynamic plantar foot forces, but not static foot posture, were associated with knee pain in people with medial knee OA. However, the amount of pain explained by increases in plantar foot force was small; thus, these associations are unlikely to be clinically meaningful.

BACKGROUND: Chronic ankle instability (CAI) has been associated with lower limb deficits that can lead to altered biomechanics during dynamic tasks. There have been contradictory findings in terms of ankle and hip joint biomechanics to date, influenced by the variety of movement tasks and varying definitions of the CAI condition.
OBJECTIVE: How do biomechanical variables of the lower extremity differ during walking, running, and jump-landing in individuals with CAI compared with those without CAI?
METHODS: Thirty-two individuals (17 CAI and 15 controls) participated in this retrospective case-control study. Sagittal and frontal plane ankle and hip joint angles and moments, and mediolateral foot balance (MLFB) were calculated during the tasks. Statistical parametric mapping (SPM) was used for the whole trajectory analysis to detect group differences. Discrete variables, including initial contact (IC) and peak angles and moments, were additionally compared.
RESULTS: No differences were found between groups during walking. During running, the CAI group exhibited a lower plantar flexor moment (p < 0.001) and more laterally deviated MLFB (p = 0.014) during mid-stance when compared to controls. Additionally, participants with CAI had a significantly greater peak plantar flexion angle in early stance (p = 0.022) and a reduced peak plantar flexor moment (p = 0.002). In the jump-landing, the CAI group demonstrated an increased hip extensor moment (p = 0.008), and a greater peak hip adduction angle (p = 0.039) shortly after ground contact compared to the control group.
CONCLUSIONS: Differences in ankle and hip biomechanics were observed between groups during running and jump landing, but not during walking. These differences may be indicative of impairments in the sensorimotor system or of learnt strategies adopted to try to minimise instability and injury risk and can help to inform future intervention design.

BACKGROUND: No in-shoe systems, measuring both components of plantar load (plantar pressure and shear stress) are available for use in patients with diabetes. The STAMPS (STrain Analysis and Mapping of the Plantar Surface) system utilises digital image correlation (DIC) to determine the strain sustained by a deformable insole, providing a more complete understanding of plantar shear load at the foot-surface interface.
OBJECTIVE: What is the normal range and pattern of strain at the foot-surface interface within a healthy population as measured by the STAMPS system? Is STAMPS a valid tool to measure the effects of plantar load?
METHODS: A cross-sectional study of healthy participants was undertaken. Healthy adults without foot pathology or diabetes were included. Participants walked 20 steps with the STAMPS insole in a standardised shoe. Participants also walked 10 m with the Novel Pedar® plantar pressure measurement insole within the standardised shoe. Both measurements were repeated three times. Outcomes of interest were global and regional values for peak resultant strain (SMAG) and peak plantar pressure (PPP).
RESULTS: In 18 participants, median peak SMAG and PPP were 35.01 % and 410.6kPa respectively. The regions of the hallux and heel sustained the highest SMAG (29.31 % (IQR 24.56-31.39) and 20.50 % (IQR 15.59-24.12) respectively) and PPP (344.8kPa (IQR 268.3 - 452.5) and 279.3kPa (IQR 231.3-302.1) respectively). SMAG was moderately correlated with PPP (r= 0.65, p < 0.001). Peak SMAG was located at the hallux in 55.6 % of participants, at the 1st metatarsal head (MTH) in 16.7 %, the heel in 16.7 %, toes 3-5 in 11.1 % and the MTH2 in 5.6 %.
CONCLUSIONS: The results demonstrate the STAMPS system is a valid tool to measure plantar strain. Further studies are required to investigate the effects of elevated strain and the relationship with diabetic foot ulcer formation.