A Pilot Study of the Effect of Outsole Hardness on Lower Limb Kinematics and Kinetics during Soccer Related Movements

Risk factors of metatarsal stress fracture associated with repetitive sports activities: a systematic review

Background

Metatarsal stress fracture is common in people engaged in repetitive weight-bearing activities, especially athletes and recruits. Identifying risk factors in these contexts is crucial for effective prevention.

Methods

A systematic search on Web of Science, PubMed, EBSCO, SPORTDiscus, MEDLINE, and Cochrane Library was conducted and the date range for the retrieval was set from January 1984 to April 2024.

Results

32 eligible studies were selected from 1,728 related research. Anatomical and biomechanical factors, such as higher foot arch, abnormal inversion/eversion of foot, and longer metatarsal length or larger angles, relatively influence stress fracture risk. However, given that there is no standardized measurement, the results remain to be examined. Soccer is associated with fifth metatarsal fractures, while long-distance running and recruit training often lead to fractures of the second or third metatarsals. High exercise intensity, non-adaptive training, and inadequate equipment heighten fracture risk.

Conclusion

This review highlights the complex interplay of anatomical, biomechanical, and sports-related factors in the risk of metatarsal stress fractures. Relatively, high arches, specific metatarsal morphologies, and foot inversion/eversion patterns are significant risk factors, particularly among athletes. Sports type also correlates with metatarsal stress fracture locations. Despite extensive research, study heterogeneity and inherent biases necessitate cautious interpretation. Comprehensive, multifactorial approaches and personalized injury prevention strategies are essential for reducing the incidence of these injuries and improving the health and performance of athletes.

Development and Validation of a Subject-Specific Coupled Model for Foot and Sports Shoe Complex: A Pilot Computational Study

Nowadays, footwear serves an essential role in improving athletic performance and decreasing the risk of unexpected injuries in sports games. Finite element (FE) modeling is a powerful tool to reveal the biomechanical interactions between foot and footwear, and establishing a coupled foot-shoe model is the prerequisite. The purpose of this pilot study was to develop and validate a 3D FE coupled model of the foot and sports shoe complex during balanced standing. All major foot and shoe structures were constructed based on the participant’s medical CT images, and 3D gait analysis was conducted to define the loading and boundary conditions. Sensitivity analysis was applied to determine the optimum material property for shoe sole. Both the plantar and shoe sole areas were further divided into four regions for model validation, and the Bland–Altman method was used for consistency analysis between methods. The simulated peak plantar and sole pressure distribution showed good consistency with experimental pressure data, and the prediction errors were all less than 10% during balanced standing with only two exceptions (medial and lateral forefoot regions). Meanwhile, the Bland–Altman analysis demonstrated a good agreement between the two approaches. The sensitivity analysis suggested that shoe sole with Young’s modulus of 2.739 MPa presented the greatest consistency with the measured data in our scenario. The established model could be used for investing the complex biomechanical interactions between the foot and sports shoe and optimizing footwear design, after it has been fully validated in the subsequent works under different conditions.

Lower limb injuries in an english professional football club: injury analysis and recommendations for prevention

BACKGROUND

Lower limb injuries constitute a problem in the sport of football. Our aim is to explore patterns and trends of lower limb injuries in an English professional football club.

METHODS

This is a descriptive epidemiological study. Reports provided by the club's physical therapy team were screened for injuries among professional football players sustained over four seasons, from 2015/2016 to 2018/2019. Data included setting of injury (in-match or training), anatomical location of injury, type of injury, number of days off and month of injury.

RESULTS

A total of 296 lower limb injuries were recorded in our study, with a rate of 11.14 per 1000 football hours. Injury rate during games was 51.38 per 1000 football hours, significantly greater than that during training at 3.81 per 1000 football hours (p = 0.021). The thigh was significantly the most commonly injured location at 4.67 per 1000 football hours (p < 0.001). Grade I tears were the most common injury type at 1.73 per 1000 football hours, significantly greater than grade III tears (p = 0.027), contusions (p = 0.043), fractures (p = 0.02), and lacerations (p = 0.019). Injury rates were found to be greatest during preseason and declined as season progressed. On average, an injury sidelined the affected footballer for a total of 20 days.

CONCLUSION

Lower limb injuries were more common during matches than training. The thigh is the most common injury location, and grade I muscle tear was the most common type of injury. Injury rates were higher early on in the season. Potential prevention strategies include spacing out competition, adopting training and exercise regimens that cater for recovery, and increasing research regarding injury mechanisms.

Foot Motion Character During Forward and Backward Walking With Shoes and Barefoot

Backward walking (BW) has been extensively used in athletic training and orthopedic rehabilitation as it may have value for enhancing balance. This study identified the differences in foot intersegment kinematics (forward walking (FW) vs. time-reversed BW) and plantar pressure parameters of 16 healthy habitually shod individuals walking FW and BW using flexible shoes (SH) and under barefoot conditions (BF). BW was found to have shorter stride length (SL) and higher stride frequency (SF) under BF conditions compared with SH, which indicates a better BW gait stability under BF conditions. Decreased HX/FF dorsiflexion at HO in BW induces less plantar aponeurosis tension which may inhibit the windlass mechanism compared to FW walking. Increased forefoot relative to hindfoot (FF/HF) pronation and sequentially hindfoot relative to tibia (HF/TB) eversion combined with medially distributed plantar pressure and a higher plantar contact area in the medial side in BW-BF maybe beneficial in maintaining balance. These results indicate that BW training may be more reliable under BF conditions compared to the SH conditions based on greater sensory information feedback from the plantar area resulting in better biomechanical behavior.