Predicting individual risk for medial tibial stress syndrome in navy recruits

Significance of tibial MRI findings of special forces recruits at the onset of their training

INTRODUCTION

MRI is commonly used to evaluate medial tibial stress syndrome (MTSS), based on grading assessments developed in civilian populations. When MTSS represents stress fracture, rest is required to allow for bone remodelling to occur. False positive evaluations can lead to unnecessary recruit attrition.

METHODS

Thirty randomly selected new recruits to a special forces training unit underwent MRI of their tibias using the T2-Dixon sequence at the onset of training. Evaluation was according to the Fredericson MTSS grading system. Prior to undergoing MRI, anthropomorphic measurements, a survey of sports history and an orthopaedic examination of subject tibias were performed. Orthopaedic follow-up was through 11 weeks of training.

RESULTS

Medial periosteal oedema without the presence of bone marrow oedema, corresponding to a grade 1 stress reaction, was present on MRI in 10 recruits (17 tibias). In only one case did the periosteal oedema include the posterior aspect of the medial cortex where medial tibial stress fractures usually occur. Tibial tenderness was present in seven tibias on examination done just prior to the MRI studies, but none were symptomatic and only one had periosteal oedema present on MRI, but without anatomical correlation between the site of the tenderness and the periosteal oedema. During subsequent training, five tibias in four recruits developed pain and tenderness. Two had periosteal oedema in their prior MRIs, but the location did not coincide anatomically with that of the tibial tenderness. The time from stopping sports before induction and the presence of periosteal oedema was not significant.

CONCLUSION

Periosteal oedema, one of the hallmarks used in MRI grading systems to evaluate MTSS, was found to have a 37.7% false positive rate for anatomically corresponding tibial tenderness at the time of the examination and during subsequent training, indicating the grading systems' low utility for the military.

Identifying special operative trainees at-risk for musculoskeletal injury using full body kinematics

Introduction: Non-combat musculoskeletal injuries (MSKIs) during military training significantly impede the US military's functionality, with an annual cost exceeding $3.7 billion. This study aimed to investigate the effectiveness of a markerless motion capture system and full-body biomechanical movement pattern assessments to predict MSKI risk among military trainees. Methods: A total of 156 male United States Air Force (USAF) airmen were screened using a validated markerless biomechanics system. Trainees performed multiple functional movements, and the resultant data underwent Principal Component Analysis and Uniform Manifold And Projection to reduce the dimensionality of the time-dependent data. Two approaches, semi-supervised and supervised, were then used to identify at-risk trainees. Results: The semi-supervised analysis highlighted two major clusters with trainees in the high-risk cluster having a nearly five times greater risk of MSKI compared to those in the low-risk cluster. In the supervised approach, an AUC of 0.74 was produced when predicting MSKI in a leave-one-out analysis. Discussion: The application of markerless motion capture systems to measure an individual's kinematic profile shows potential in identifying MSKI risk. This approach offers a novel way to proactively address one of the largest non-combat burdens on the US military. Further refinement and wider-scale implementation of these techniques could bring about substantial reductions in MSKI occurrence and the associated economic costs.

Comparison of optimized machine learning approach to the understanding of medial tibial stress syndrome in male military personnel

PURPOSE

This study investigates the applicability of optimized machine learning (ML) approach for the prediction of Medial tibial stress syndrome (MTSS) using anatomic and anthropometric predictors.

METHOD

To this end, 180 recruits were enrolled in a cross-sectional study of 30 MTSS (30.36 ± 4.80 years) and 150 normal (29.70 ± 3.81 years). Twenty-five predictors/features, including demographic, anatomic, and anthropometric variables, were selected as risk factors. Bayesian optimization method was used to evaluate the most applicable machine learning algorithm with tuned hyperparameters on the training data. Three experiments were performed to handle the imbalances in the data set. The validation criteria were accuracy, sensitivity, and specificity.

RESULTS

The highest performance (even 100%) was observed for the Ensemble and SVM classification models while using at least 6 and 10 most important predictors in undersampling and oversampling experiments, respectively. In the no-resampling experiment, the best performance (accuracy = 88.89%, sensitivity = 66.67%, specificity = 95.24%, and AUC = 0.8571) was achieved for the Naive Bayes classifier with the 12 most important features.

CONCLUSION

The Naive Bayes, Ensemble, and SVM methods could be the primary choices to apply the machine learning approach in MTSS risk prediction. These predictive methods, alongside the eight common proposed predictors, might help to more accurately calculate the individual risk of developing MTSS at the point of care.

Externally validated machine learning algorithm accurately predicts medial tibial stress syndrome in military trainees: a multicohort study

Objectives

Medial tibial stress syndrome (MTSS) is a common musculoskeletal injury in both sporting and military settings. No reliable treatments exist, and reoccurrence rates are high. Prevention of MTSS is critical to reducing operational burden. Therefore, this study aimed to build a decision-making model to predict the individual risk of MTSS within officer cadets and test the external validity of the model on a separate military population.

Design

Prospective cohort study.

Methods

This study collected a suite of key variables previously established for predicting MTSS. Data were obtained from 107 cadets (34 women and 73 men). A follow-up survey was conducted at 3 months to determine MTSS diagnoses. Six ensemble learning algorithms were deployed and trained five times on random stratified samples of 75% of the dataset. The resultant algorithms were tested on the remaining 25% of the dataset, with models then compared for accuracy. The most accurate new algorithm was tested on an unrelated data sample of 123 Australian Navy recruits to establish external validity of the model.

Results

Calibrated random forest modelling was the most accurate in identifying a diagnosis of MTSS; (area under curve (AUC)=98%, classification accuracy (CA)=96%). External validation on a sample of Navy recruits resulted in comparable accuracy; (AUC=95%, CA=94%). When the model was tested on the combined datasets, similar accuracy was achieved; (AUC=92%, CA=91%).

Conclusion

This model is highly accurate in predicting those who will develop MTSS. The model provides important preventive capacity which should be trialled as a risk management intervention.

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.

Risk factors for musculoskeletal injuries in the military: a qualitative systematic review of the literature from the past two decades and a new prioritizing injury model

BACKGROUND

Musculoskeletal injuries (MSkIs) are a leading cause of health care utilization, as well as limited duty and disability in the US military and other armed forces. MSkIs affect members of the military during initial training, operational training, and deployment and have a direct negative impact on overall troop readiness. Currently, a systematic overview of all risk factors for MSkIs in the military is not available.

METHODS

A systematic literature search was carried out using the PubMed, Ovid/Medline, and Web of Science databases from January 1, 2000 to September 10, 2019. Additionally, a reference list scan was performed (using the "snowball method"). Thereafter, an international, multidisciplinary expert panel scored the level of evidence per risk factor, and a classification of modifiable/non-modifiable was made.

RESULTS

In total, 176 original papers and 3 meta-analyses were included in the review. A list of 57 reported potential risk factors was formed. For 21 risk factors, the level of evidence was considered moderate or strong. Based on this literature review and an in-depth analysis, the expert panel developed a model to display the most relevant risk factors identified, introducing the idea of the "order of importance" and including concepts that are modifiable/non-modifiable, as well as extrinsic/intrinsic risk factors.

CONCLUSIONS

This is the qualitative systematic review of studies on risk factors for MSkIs in the military that has attempted to be all-inclusive. A total of 57 different potential risk factors were identified, and a new, prioritizing injury model was developed. This model may help us to understand risk factors that can be addressed, and in which order they should be prioritized when planning intervention strategies within military groups.

Are Leg Muscle, Tendon and Functional Characteristics Associated with Medial Tibial Stress Syndrome? A Systematic Review

Background

Medial tibial stress syndrome (MTSS) is a common overuse injury that lacks effective evidence-based treatment options. Reduced leg girth has been associated with MTSS development because it is hypothesised to impair the ability of the leg to modulate tibial loading generated during foot–ground contact. Measuring total leg girth, however, does not provide specific information about the structural composition or functional capacity of individual leg muscles. Consequently, uncertainty remains as to which specific muscles are compromised and contribute to MTSS development. Therefore, this paper aimed to systematically review the body of literature pertaining to how the structure and function of the leg muscles are thought to be associated with MTSS injury.

Methods

The review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P). Medline, PubMed, SCOPUS, SPORTDiscus with Full-texts and Web of Science were searched until March 2021 to identify articles in which lower limb muscle structural or functional variables associated with MTSS injury were investigated.

Results

Seventeen studies, which were predominately case–control in design and captured data from 332 individuals with MTSS symptoms and 694 control participants, were deemed appropriate for review. The average Downs and Black Quality Assessment score was 71.7 ± 16.4%, with these articles focussing on leg girth, tendon abnormalities, muscle strength and endurance, shear modulus and neuromuscular control. Of the risk factors assessed in the 17 studies, decreased lean leg girth and higher peak soleus muscle activity during propulsion were most strongly correlated with MTSS development. Individuals with MTSS also displayed deficits in ankle plantar flexor endurance, greater isokinetic concentric eversion strength, increased muscle shear modulus and altered neuromuscular recruitment strategies compared to asymptomatic controls.

Conclusions

Future prospective studies are required to confirm whether decreased lean leg girth and higher peak soleus muscle activity during propulsion are associated with MTSS development and to elucidate whether these structural and functional differences in the leg muscles between MTSS symptomatic and asymptomatic controls are a cause or effect of MTSS.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40798-021-00362-2.

Successful Treatment of Medial Tibial Stress Syndrome with Interosseous Membrane Acupuncture: A Case Series

Background: Medial tibial stress syndrome (MTSS), otherwise known as shin splints, frequently causes pain and disability in the physically active population and can be recalcitrant to treatment. Interventional and alternative therapies, specifically acupuncture, for treatment of MTSS have been poorly described in the literature. The aim of this case series is to describe an acupuncture technique for the treatment of MTSS. Cases: Patients who received the diagnosis of MTSS were treated in an outpatient military treatment facility. One Hwato^® 0.30 mm × 75 mm needle was placed 1 cun distal and 1 cun lateral to the tibial tuberosity of the affected leg and was inserted deeply through the plane of the interosseous membrane. A second needle was then placed 2 cun distal to the first needle in the same trajectory and at the same depth. Needles were then irregularly stimulated for 5 minutes before needle removal. After treatment, the patient vigorously moved the affected leg before reassessing pain. Results: Both patients noted a clinically significant decrease in pain immediately after intervention, which lasted for 4 weeks. Conclusions: Interosseous membrane acupuncture is a clinically significant, effective means to decrease MTSS-associated pain in physically active adults. This case series demonstrates a technique to augment conservative therapy of patients with MTSS.

Musculoskeletal injuries in military personnel-Descriptive epidemiology, risk factor identification, and prevention

OBJECTIVES

To provide an overall perspective on musculoskeletal injury (MSI) epidemiology, risk factors, and preventive strategies in military personnel.

DESIGN

Narrative review.

METHODS

The thematic session on MSIs in military personnel at the 5th International Congress on Soldiers' Physical Performance (ICSPP) included eight presentations on the descriptive epidemiology, risk factor identification, and prevention of MSIs in military personnel. Additional topics presented were bone anabolism, machine learning analysis, and the effects of non-steroidal anti-inflammatory drugs (NSAIDs) on MSIs. This narrative review focuses on the thematic session topics and includes identification of gaps in existing literature, as well as areas for future study.

RESULTS

MSIs cause significant morbidity among military personnel. Physical training and occupational tasks are leading causes of MSI limited duty days (LDDs) for the U.S. Army. Recent studies have shown that MSIs are associated with the use of NSAIDs. Bone MSIs are very common in training; new imaging technology such as high resolution peripheral quantitative computed tomography allows visualization of bone microarchitecture and has been used to assess new bone formation during military training. Physical activity monitoring and machine learning have important applications in monitoring and informing evidence-based solutions to prevent MSIs.

CONCLUSIONS

Despite many years of research, MSIs continue to have a high incidence among military personnel. Areas for future research include quantifying exposure when determining MSI risk; understanding associations between health-related components of physical fitness and MSI occurrence; and application of innovative imaging, physical activity monitoring and data analysis techniques for MSI prevention and return to duty.

Is high soleus muscle activity during the stance phase of the running cycle a potential risk factor for the development of medial tibial stress syndrome? A prospective study

To assess the impact of lower-leg muscle activity during the stance phase of running on the development of medial tibial stress syndrome (MTSS), in 123 healthy participants (18.2 ± 0.8 years), dynamic and static foot posture, and soleus and tibialis anterior muscle activity during the stance phase of running were measured before a 17-week track- and field-course. After the course, MTSS was identified in 20.5% of the participants. MTSS participants had a higher body mass (ES = 1.13), body mass index (BMI) (ES = 1.31), lower previous vigorous physical activity level (ES = 0.84) and VO_2max (ES = 0.61), greater dynamic foot pronation (ES = 0.66), higher soleus peak EMG amplitude during the absorption (ES = 0.60) and propulsion phases (ES = 0.56) of running, and a history of MTSS (OR = 6.38) (p < 0.05). Stepwise logistic regression showed BMI, dynamic foot index, soleus peak EMG amplitude during propulsion, MTSS history and previous vigorous physical activity were predictors of MTSS. The model predicted 96.6% of the healthy participants and 56.5% of the MTSS participants and correctly classified 88.4% of overall cases. Coaches and sports-medicine professionals that screen for injury risk should consider adopting a comprehensive evaluation that includes these parameters.

Incidence and risk factors of medial tibial stress syndrome: a prospective study in Physical Education Teacher Education students

Objective

Medial tibial stress syndrome (MTSS) is a common lower extremity overuse injury often causing long-term reduction of sports participation. This study aimed to investigate the incidence and risk factors of MTSS in first-year Dutch Physical Education Teacher Education (PETE) students.

Methods

This prospective study consisted of physical measures at baseline (height, weight, fat percentage, 3000 m run test, navicular drop test, hip internal and external range of motion, hip adduction and adduction strength, single leg squat and shin palpation), an intake questionnaire at baseline (age, sport participation, presence of MTSS, MTSS history, insole use and use of supportive shoes) and an MTSS registration procedure during the academic year of 2016–2017 (10  months) using a validated questionnaire. In total 221 first-year PETE students were included, of whom 170 (77%) were male and 51 (23%) female. The evaluation of risk factors was conducted with univariable and multivariable logistic generalised estimating equation analyses.

Results

In total 55 (25%) subjects, 35 (21%) men and 20 (39%) women, developed MTSS during the follow-up period. The associated risk factors were female sex (OR=3.14, 95% CI 1.39 to 7.11), above-average age (OR=0.31, 95% CI 0.13 to 0.76), above-average body mass index (OR=2.29, 95% CI 1.02 to 5.16) and history of MTSS (OR=5.03, 95% CI 1.90 to 13.30).

Conclusion

The incidence of MTSS is high in PETE students. Several risk factors were identified. These results demonstrate the need for prevention and may provide direction to preventive intervention design.

Risk factors for lower limb injuries during initial naval training: a prospective study

Introduction

This study aimed to identify risk factors associated with the development of common lower limb injuries during initial defence training in naval recruits who were enrolled in a randomised trial.

Methods

Three-hundred and six naval recruits were randomly allocated flat insoles (n=153) or foot orthoses (n=153) while undertaking 11 weeks of initial training. Participant characteristics (including anthropometrics, general health, physical activity, fitness and foot characteristics) were collected at the baseline assessment and injuries were documented prospectively. Injury was defined as the combined incidence of participants with medial tibial stress syndrome, patellofemoral pain, Achilles tendinopathy and plantar fasciitis/plantar heel pain throughout the 11 weeks of training. A discriminant function analysis was used to explore the ability of baseline measures to predict injury.

Results

Overall, 67 (21.9%) participants developed an injury. Discriminant function analysis revealed that participants who sustained an injury were slightly younger (mean 21.4±SD 4.1 vs 22.5±5.0 years) and were less likely to be allocated to the foot orthosis group (40% vs 53%) compared with those who remained uninjured. The accuracy of these baseline variables to predict injury was moderate (78.1%).

Conclusions

Lower limb injury was not accurately predicted from health questionnaires, fitness results and clinical assessments in naval recruits undertaking initial defence training. However, although not reaching statistical significance, the use of foot orthoses may be protective against common lower limb injuries.

Trial registration number

ACTRN12615000024549; Post-results.