Forefoot and hindfoot kinematics in subjects with medial tibial stress syndrome during walking and running

Medial Tibial Stress Syndrome: A Scoping Review of Epidemiology, Biomechanics, and Risk Factors

Regular physical activity confers numerous health and social benefits; however, activity-related lower-limb overuse injuries are prevalent. Medial tibial stress syndrome (MTSS) is a common overuse injury of the lower extremity. It is frequently observed in athletes and in military personnel. It involves exercise-induced pain over the anterior tibia and is an early stress injury in the continuum of tibial stress fractures (TSF). This scoping review aims to synthesize and characterize the literature on MTSS, identify knowledge gaps, and propose future research directions. We conducted a scoping review of the literature, which was informed by the Joanna Briggs Institute and the Arksey and O'Malley methodology, by searching four databases until December 31, 2023. The references were screened by two authors based on their titles, abstracts, and full texts to ensure that they met the inclusion criteria. Data related to the research objectives were extracted, analyzed, and reported numerically and descriptively. Thirty-seven studies were included in the current review, most of which recruited athletes as the study participants (67.6%). This was followed by articles about military members (16.2%). The highest prevalence of MTSS has been reported among recreational marathon runners in India (69.5%). The highest incidence of MTSS was reported in a German study (35.7%). Two studies reported that participants with MTSS had a higher body mass index (BMI) than those without MTSS, and one study found a significant correlation between BMI and the time required for complete recovery. Two studies reported that individuals with greater experience in athletic activities were at a lower risk of developing MTSS later in their careers. In contrast, another study reported that ultramarathon running increases the incidence of MTSS overuse injuries. Traction theory as a cause of MTSS was examined in five studies, and the mean navicular drop test (NDT) score was assessed in three studies. Biomechanical evaluation of ankle disorders and MTSS was performed in five articles and hip abnormalities in four articles. This review identifies research areas on the influence of epidemiological, risk, and biomechanical factors on MTSS development. Such research could inform counseling for patients concerned about MTSS risk factors and curative measures, as well as optimize surveillance and subsequent management of MTSS outcomes.

How Medial Tibial Stress Syndrome Is Affected by Alignment, Range of Motion, Strength, and Gait Biomechanics: A Systematic Review and Meta-Analysis

CONTEXT

Medial tibial stress syndrome (MTSS) is a common chronic injury of the lower-extremity in the physically active population. However, the risk factors for MTSS remain unclear.

OBJECTIVE

This study identified the risk factors for MTSS and established the continuum model of lower-extremity alignments, range of motion, muscular strength, and gait kinematics affecting each other and MTSS development.

EVIDENCE ACQUISITION

Online databases including PubMed, CINAHL, SPORTDiscus, and Web of Science were used to retrieve studies related to risk factors for MTSS. The study eligibility criteria were studies that used the MTSS definition of the Yates and White criteria, or included participants with MTSS, except for stress fracture and compartment syndrome. A total of 2099 papers were retrieved during the initial search stage. After screening, based on eligibility criteria and cross-reference, 21 papers were included in this study. Data on lower-extremity alignments, range of motion, muscular strength, and gait biomechanics were extracted as outcome variables for this meta-analysis. Publication bias was assessed using funnel plots and Egger's regression analysis.

EVIDENCE SYNTHESIS

Foot posture index (standardized mean difference [SMD] = 1.23; 95% CI, 0.02-2.43), intercondylar interval (SMD = 0.29; 95% CI, 0.10-0.48), inversion range of motion (SMD = 0.37; 95% CI, 0.10-0.63), eversion strength (SMD = 0.37; 95% CI, 0.10-0.65), and dynamic arch height change during walking (SMD = 1.05; 95% CI, 0.49-1.60) were significant risk factors for MTSS. Egger's regression analysis revealed asymmetry in several variables, which indicates publication bias. The trim-and-fill method was applied to these variables. A comparison between the SMD and adjusted SMD showed that the variables had minimal impacts on the meta-analysis.

CONCLUSIONS

Based on our results, health care professionals should assess the significant risk factors in patients before participation in physical activities and treat them to prevent and rehabilitate MTSS.

Acute effects of the short-foot exercise in runners with medial tibial stress syndrome: A quasi-experimental study

OBJECTIVES

Analyze whether there are immediate changes in peak soleus activation and peak hindfoot eversion after short-foot exercise (SFE) in runners with medial tibial stress syndrome (MTSS). Secondarily, establish differences in peak soleus activation and peak hindfoot eversion between asymptomatic individuals and those presenting MTSS.

DESIGN

Quasi-experimental study.

SETTING

University Laboratory.

PARTICIPANTS

Thirty-two runners participated: 16 with MTSS and 16 in the no-pain group (NPG).

MAIN OUTCOME MEASURES

Soleus activation was measured using electromyography, and hindfoot eversion via 3D kinematic analysis. Participants performed SFE, and running data were collected at 9,12 and 15 km/h pre- and post-intervention.

RESULTS

SFE reduced peak soleus activation at 9 (p = 0.017) and 15 km/h (p = 0.019) for the MTSS group and at 15 km/h (p < 0.001) for the NPG, suggesting improved neuromuscular efficiency and potentially reduced tibial stress. SFE did not significantly affect peak hindfoot eversion. Significant correlations were found between ankle dorsiflexion range of motion and muscle activation (r = 0.585 to 0.849, p < 0.05). These findings suggest SFE could improve neuromuscular efficiency and reduce tibial stress, and highlights ankle flexibility's role in muscle activation.

CONCLUSIONS

SFE significantly reduces soleus activation, potentially improving neuromuscular efficiency and decreasing tibial stress.

Foot torsional stiffness exhibits gender differences but shows no correlation with medial longitudinal arch height

Although foot mobility tends to be greater in females, sex-based differences in foot torsional stiffness have not been investigated. It is also unclear whether assessing the medial longitudinal arch (MLA) height reflects foot torsional stiffness. This study included 52 healthy adults (26 females and 26 males) with an average age of 24.6 years. The arch height index was used to assess MLA height. To calculate foot torsional stiffness, a custom-built torque meter and a three-dimensional motion analysis system were employed. The forefoot was passively rotated from the maximum eversion to the maximum inversion at a rate of 2.5°/s. The forefoot's resistance torque and rotation angle relative to the rearfoot were recorded. Foot torsional stiffness was defined by establishing the slope of the regression line from 10° eversion to 10° inversion of the torque-angle curve, with the slope subsequently normalized by body weight. Gender differences in foot torsional stiffness and the correlation between MLA height and foot torsional stiffness were investigated. Foot torsional stiffness was significantly lower in females than in males (0.00237 ± 0.00061Nm/°･kg vs 0.00368 ± 0.00136 Nm/°･kg, p < 0.001, effect size: r = 0.65, statistical power = 0.99). MLA height was not significantly different between sexes. No significant correlations were found between foot torsional stiffness and MLA height in either sex. Foot torsional stiffness and MLA height reflect different mechanical properties of the foot, emphasizing the need for individual assessment and consideration of sex differences.

In-shoe multi-segment foot kinematics measurement during the stance phase of running using a stretch strain sensor

Multi-segment foot kinematics during shod running are difficult to investigate in clinical settings. Stretch strain sensors can measure foot kinematics; however, whether they can evaluate foot kinematics during shod running or at the midfoot kinematics remains unclear. The aim of this study was to investigate the stretch strain sensor could reveal differences between shod and barefoot conditions and midfoot kinematics during running. Eighteen healthy adults were included in the study. A stretch strain sensor and three-dimensional motion capture system were used to measure foot kinematics during barefoot and shod running with a rearfoot strike pattern. The correlation between the amplitudes of the two signals during barefoot running was investigated, and the similarity between the two signals was evaluated using the cross-correlation coefficient. Statistical parametric mapping was used to compare shod and barefoot conditions. Shod running had significantly lower sensor strain from 30 % to 100 % stance compared to barefoot running (p < 0.05). The sensor amplitude was significantly correlated with the shank-rearfoot frontal (r = 0.668, p = 0.002), the rearfoot-midfoot transverse (r = 0.546, p = 0.02), and the midfoot-forefoot sagittal planes (r = 0.563, p = 0.01). A high cross-correlation was observed between the sensor signal and the shank-rearfoot sagittal, frontal, and transverse planes and the midfoot-forefoot sagittal plane. This sensor can be used to investigate foot kinematics during shod running. The sensor signal mainly reflects the shank-rearfoot frontal and midfoot-forefoot sagittal planes, as well as the maximum kinematic range of the rearfoot-midfoot transverse plane.

Contribution of the tibialis posterior and peroneus longus to inter-segment coordination of the foot during single-leg drop jump

Abnormal foot motion is considered to be related to sports related injuries. This study aimed to identify the relationship between calf muscle activity and inter-segment coordination of the foot during single-leg drop jumps. Eleven healthy men participated and performed single-leg drop jumps from a 30-cm box. Muscle activity of the tibialis posterior (TP), flexor digitorum longus, peroneus longus (PL) and gastrocnemius were measured. The rearfoot and midfoot segment angle from landing to leaping were calculated according to the Rizzoli Foot Model and time scaled to 100%. A modified vector coding technique was employed to classify inter-segment coordination of every 1% into four patterns (in-phase, anti-phase, rearfoot phase,and midfoot phase). The relationship between percentage of each pattern and muscle activity levels were statistically analysed with correlation coefficient. The TP showed a significant positive correlation with percentage of in-phase in coronal plane (r = 0.61, p = 0.045). The PL also showed a trend of positive correlation to in-phase in coronal plane (r = 0.59, p = 0.058). TP and PL muscle activities may modulate the inter-segment coordination between the rearfoot and midfoot in coronal plane. Clinically, these muscles should be assessed for abnormal inter-segment foot motion.

Differences in the coordination and its variability among foot joints during running in neutral foot and flatfoot

Flatfoot is a well-known foot deformity, with a prevalence of 11.2%-29.0% among adults. Running injuries can occur in individuals with flatfoot; however, the underlying mechanism remains unknown. We investigated the coordination pattern and variability among foot joints while running by comparing participants with neutral foot and with flatfoot. Participants with neutral foot (n = 15) and flatfoot (n = 15) were asked to run at their preferred speed. Using the modified vector coding technique, the coupling angle between the foot joints, representing interjoint coordination, was calculated and categorized into four coordination patterns. The standard deviation of the coupling angle was computed to measure the coordination variability during the stance phase. There were no differences in the spatiotemporal parameters (speed, step length, and cadence) between the groups. In the sagittal rearfoot and sagittal midfoot coordination patterns, the flatfoot group showed a significantly greater proportion of anti-phase with proximal dominancy and a lower proportion of in-phase with proximal dominancy than the neutral foot group during early stance. Coordination variabilities between the sagittal rearfoot and sagittal midfoot (midstance), between the sagittal midfoot and sagittal forefoot (early stance), and between the frontal rearfoot and sagittal midfoot (midstance) were greater in the flatfoot group than in the neutral foot group. This may explain why those with flatfoot are likely to experience running injuries.

Biomechanical characteristics of the lower extremities during running in male long-distance runners with a history of medial tibial stress syndrome: a case control study

BACKGROUND

Medial tibial stress syndrome (MTSS) is a running-related injury of the lower extremities. After returning to competition, there are often recurring episodes of MTSS. Therefore, it is important to prevent the onset and recurrence of MTSS among long-distance runners. This case-control study aimed to compare the kinematics and kinetics of runners with and without previous MTSS during running to clarify the biomechanical characteristics of the lower extremity of runners with previous MTSS.

METHODS

Thirteen male long-distance runners aged over 18 years and asymptomatic at the time of measurement were divided into an MTSS group and a non-MTSS group based on their history of MTSS as reported in a questionnaire. The kinetics and kinematics of running were analyzed when participants ran at a speed of 2.0 ± 0.2 m/s by a three-dimensional motion analysis system and two force plates. Data regarding the joint angles, moments, and powers of the ankle, knee, and hip during the stance phase while running were extracted and compared between the two groups using the Mann-Whitney U test.

RESULTS

Of the 13 participants, 5 and 8 were included in the MTSS (10 legs) and non-MTSS (16 legs) groups, respectively. The ankle maximum eversion moment was significantly larger in the MTSS group than in the non-MTSS group (p = 0.04). There were no significant differences in other parameters.

CONCLUSIONS

This study found that the ankle maximum eversion moment during the stance phase of running was larger in the MTSS group than in the non-MTSS group. Even after the disappearance of the symptoms of MTSS, the running biomechanics of participants with previous MTSS differed from those of participants without previous MTSS.

The prevalence and effect of the sites of pain in female soccer players with medial shin pain

BACKGROUND

Female soccer players are often diagnosed with medial shin pain, which includes tibial stress fracture, medial tibial stress syndrome, and chronic exertional compartment syndrome. As the possibility of varied sites of pain affecting sports activities has not been fully researched, an urgent discussion and evidence is required. This study investigates the prevalence and effect of sites of pain on the sports activities of female soccer players with medial shin pain.

METHODS

A questionnaire survey was conducted for 196 female soccer players with medial shin pain to assess symptom duration, the effect of practice and performance, and sites of pain. The players were classified into three conditions (tibial stress fracture, medial tibial stress syndrome, or medial shin pain with neurological symptoms) and compared based on sites of pain.

RESULTS

We observed that medial tibial stress syndrome had a lower impact on performance compared to that of tibial stress fracture and medial shin pain with neurological symptoms. While participants with tibial stress fracture had to suspend practice sessions more frequently, the difference in symptom duration between the classified groups was not statistically significant. The effect of sites of pain on sports activities was not significantly different in participants with medial tibial stress syndrome.

CONCLUSIONS

Medial shin pain should be evaluated carefully to differentiate between medial tibial stress syndrome and medial shin pain with neurological symptoms. Restriction of sports activities may help improve the patient's condition early, regardless of the presentation.

An Elastic Foot Orthosis for Limiting the Increase of Shear Modulus of Lower Leg Muscles after a Running Task: A Randomized Crossover Trial

BACKGROUND

Excessive foot pronation may be attributed to an increasing burden on leg muscles during running, which might be a factor in medial tibial stress syndrome. We developed an elastic foot orthosis (EFO) that can decrease foot pronation and aimed to identify whether this orthosis could limit the increase in lower leg muscle hardness after running.

METHODS

Twenty-one healthy volunteers participated in this randomized crossover trial with an elastic or sham foot orthosis (SFO). All volunteers ran on a treadmill for 60 min while wearing either orthosis. Muscle hardness of the posterior lower leg was assessed using shear wave elastography before and after running. The Wilcoxon signed rank test was used to compare muscle hardness between the two orthotic conditions.

RESULTS

No significant differences were observed between the two orthotic conditions before running (p > 0.05). After running, the flexor digitorum longus (FDL) hardness in the EFO group was significantly lower than that in the SFO group (p < 0.01). No significant changes were observed in the other muscles.

CONCLUSION

The results suggest that the EFO can restrict the increase in FDL hardness with running. The EFO may be an effective orthotic treatment for medial tibial stress syndrome.

Efficacy of kinesiology taping on the management of shin splints: a systematic review

BACKGROUND

Shin splint is one of the most common sports injuries after strenuous exercise. Kinesiology taping (KT) is a popular noninvasive remedy used in sports-related disorders, with the potential effects of relieving pain, facilitating proprioception, modulating muscle activation and correcting abnormal movement patterns. However, the exact efficacy of KT on shin splints is still unknown, and previous findings are inconsistent. Hence, this study aimed to conduct a systematic review to evaluate the current status of relevant evidence on its efficacy.

METHODS

The review was performed according to the PRISMA guidelines, and a systematic search of the literature was conducted in December 2020. Electronic databases, Embase, Scopus, Medline, Web of Science, PubMed and Biomed Central were searched for the identification of pertinent studies with pre-defined key terms on shin splints and KT.

RESULTS

Four studies with a total sample size of 141 participants were included and analyzed. Two studies had within-subject designs, whereas the other two were randomized clinical trials. Although the positive results of KT were reported by the studies, methodological quality varied from poor to moderate according to the Physiotherapy Evidence Database Scale or Non-Randomized Studies-of Interventions.

CONCLUSION

In conclusion, this review revealed that the efficacy of KT on shin splints remains not clear. Evidence that supports its effectiveness in individuals with shin splints is currently limited. Further studies with good methodological quality and study design are warranted.

Validation of the RunScribe inertial measurement unit for walking gait measurement

Introduction

The use of portable gait measurement systems in research is appealing to collect real-world data at low-cost, low participant burden, and without requirement for dedicated lab space. Most commercially available inertial measurement units (IMU’s) designed for running only capture temporospatial data, the ability to capture biomechanics data such as shock and motion metrics with the RunScribe IMU makes it the closest to a lab alternative. The RunScribe system has been validated in running, however, is yet to be validated for walking.

Method

Qualisys motion capture, AMTI force plates, and Delsys Trigno accelerometers were used as gold standard lab measures for comparison against the RunScribe IMU. Twenty participants completed 10 footsteps per foot (20 total) measured by both systems simultaneously. Variables for validation included: Vertical Ground reaction force (GRF), instantaneous GRF rate, pronation excursion, pronation velocity, total shock, impact force, braking force. Interclass correlation (ICC) was used to determine agreement between the measurement systems, mean differences were used to evaluate group level accuracy.

Results

ICC results showed moderate agreement between measurement systems when both limbs were averaged. The greatest agreement was seen for GRF rate, pronation excursion, and pronation velocity (ICC = 0.627, 0.616, 0.539), low agreement was seen for GRF, total shock, impact shock, braking shock (ICC = 0.269, 0.351, 0.244, 0.180). However mean differences show the greatest level of accuracy for GRF, GRF rate, and impact shock.

Discussion

Results show mixed agreement between the RunScribe and gold standard lab measures, and varied agreement across left and right limbs. Kinematic variables showed the greatest agreement, however GRF had the lowest relative mean difference for group results. The results show acceptable levels of agreement for most variables, however further work must be done to assess the repeatability and sensitivity of the RunScribe to be applied within areas such as footwear testing and gait retraining protocols.

Biomechanical analysis of two runners who developed leg injuries during a six-week transition to maximal running shoes: A case series

Achilles tendinopathy (AT) and medial tibial stress syndrome (MTSS) are two of the most common running-related injuries. In a previous study investigating running biomechanics before and after a six-week transition to maximal running shoes, two runners dropped out of this study due to Achilles pain and shin pain, respectively. The purpose of this case series was to investigate running biomechanics in those two runners, identifying potential causes for injury in relation to maximal shoe use. Running biomechanics were collected in a laboratory setting for these two runners wearing both a maximal running shoe and traditional running shoe before the six-week transition using an 8-camera motion capture system and two embedded force plates. Both runners displayed prolonged eversion in the maximal shoe, which has been previously cited as a potential risk factor for developing Achilles tendinopathy and medial tibial stress syndrome. Relatively high loading rates and impact forces were also observed in the runner with shin pain in the maximal shoe, which may have contributed to their pain. More prospective research on injury rates in individuals running in maximal shoes is needed.

Validity and reproducibility of foot motion analysis using a stretch strain sensor

BACKGROUND

Multi-segment foot analysis is traditionally challenging to perform while subjects are wearing footwear or a foot orthosis and is difficult to apply in the clinical setting. A recently developed stretch strain sensor (STR), that is thin and highly flexible, may solve this limitation because it does not require observation using a camera and is highly portable.

RESEARCH QUESTION

This study aimed to examine the reproducibility and validity of foot motion analysis using the STR during walking and running by comparing it with a conventional motion capture system.

METHODS

Twenty-one healthy participants were examined in this study. The STR was placed on the participant's foot in one of two locations in separate experiments (spring ligament; SL and navicular drop; ND methods). Foot kinematic data during walking and running were simultaneously recorded using the STR and a three-dimensional motion capture system. Intra-class correlation (ICC) was used to assess test-retest reproducibility of the STR method. Cross-correlation coefficient evaluated the similarity of the pattern of the signals between the two systems. Pearson and Spearman correlation analysis was used to evaluate the relationships between the STR measurement and angular excursion of the forefoot or hindfoot.

RESULTS

The ICCs of the SL method were 0.95 and 0.96, and those of the ND method were 0.93 and 0.71 during walking and running, respectively. In the SL method, the pattern of the signals between the STR and forefoot frontal motion was strongly correlated. The STR measurement was significantly correlated with forefoot eversion excursion (walking: r=-0.67, running: r=-0.64, p < 0.01 each). In the ND method, the STR signal was not associated with forefoot and hindfoot kinematics.

SIGNIFICANCE

Our results showed that the STR has acceptable reproducibility and validity of foot motion analysis. This system may enable measurement of foot motion while subjects are wearing shoes and outside the laboratory.

Differences in rearfoot, midfoot, and forefoot kinematics of normal foot and flatfoot during running

Flatfoot is a common foot deformity, which could contribute to running injuries such as medial tibial stress syndrome. Intrafoot kinematics of flatfoot during walking have often been documented using multisegment foot models. However, the intrafoot kinematics of flatfoot during running remains unclear, despite the possible relationship between flatfoot and running injuries. We aimed to clarify rearfoot, midfoot, and forefoot kinematics when running in participants with normal foot and flatfoot. Participants with the normal foot (n = 14) and flatfoot (n = 14) were asked to runover-ground at their preferred speed. Three-dimensional kinematics of the rearfoot, midfoot, and forefoot during running were calculated based on the Rizzoli foot model. A two-sample t-test of statistical parametric mapping was performed to determine differences between normal foot and flatfoot in time histories of intrafoot kinematics during running. No differences were found between groups in characteristics and spatiotemporal parameters. In the frontal rearfoot angle, a significantly increased eversion from 24% to 100% (p < .001) was observed in the flatfoot compared to the normal foot. At the midfoot angle, a significantly increased eversion from 0% to 4% (p < .049) and 21% to 100% (p < .001) was observed in the flatfoot compared to the normal foot. At the forefoot angle, a significantly increased inversion from 6% to 17% (p < .047) was observed in the flatfoot compared to the normal foot. These findings may be useful to explain why flatfoot could contribute to running injuries such as medial tibial stress syndrome.