Successful injury prevention should involve informing and educating those involved in all aspects of military training. Injury prevention programs that involve education are more likely to increase adherence and show success [4]. Education includes dissemination of information regarding the proven strategies for the prevention of injury, educating those who deliver training programs, and those who are responsible for training troops at all levels. Perhaps most importantly, effective education is a crucial component for obtaining military commanders’ support for evidence-based injury prevention interventions that are aligned with their responsibility to protect service members [3].

Without adequate and widespread surveillance, it is difficult to appreciate the magnitude of the MSK-I problem in the military, which presents challenges for deciding where to intervene. Surveillance reporting on specific injuries (e.g., stress fracture) and training events (e.g., pugil sticks) provides the foundation for identifying problem areas and informing improvement strategies. Through the synthesis of information about injury rates and training by unit level, training cycle, fiscal or calendar year, and goals for improvement, targeted interventions can be thoroughly evaluated and recommendations made in an evidenced-based manner .

Numerous Department of Defense (DoD)-wide surveillance systems exist, including the Defense Medical Surveillance System (DMSS) administered by the Armed Forces Health Surveillance Center (AFHSC), and the Military Health System Data Repository (MDR). However, more importantly, most training units carefully track their own outcomes, including number of dropped trainees, unit fitness test performance, and in coordination with medical staff, in-house injury rates. Routine surveillance of unit-level injuries and fitness can and should be used as an indicator of physical training program success or failure and is an invaluable tool for garnering leadership support. Local injury surveillance infrastructure and data are also critical for providing timely and actionable data to military leaders at the strategic, operational, and tactical levels .

Leadership focus at all levels of the organization, from the highest-level military commanders to the squad leader, has the greatest influence on MSK-I rates and whether an injury prevention intervention will be successful or not. Simply understanding the current state of specific injuries, their contributing causes, setting goals to improve outcomes, and monitoring success through surveillance can be an effective way to gain leadership support for injury prevention initiatives. High injury rates indicate a need to modify existing training programs, with command-level decisions having broad-reaching impacts. Regular reporting of injury data through the chain of command may have the effect of encouraging greater command responsibility for unit performance, including MSK-I. However, most importantly, recent work shows that successful short-term prevention program implementation and ultimate long-term sustainability are only possible with complete leadership buy-in and support [5]. Key to obtaining this support is aligning the mutual goal of injury prevention along with the overall mission of military leaders (i.e., operational readiness). Both buy-in and support from leaders and key stakeholders are paramount to garnering commitment for successful implementation and ultimate sustainability of injury prevention initiatives [5].

While there have been many successful injury prevention programs reported, there are many more that lack sufficient evidence for implementation. There is a great need for branch or service-level research and program evaluation of multiple types of injury prevention strategies in military populations. More importantly, there is a great need for the willingness and desire to devote resources to implement, disseminate, track, and evaluate new strategies for injury prevention. The following section describes the latest research and program evaluation for successful military injury prevention strategies.

Training-related risk factors for MSK-I have been clearly identified [6–8]. Risk factors have traditionally been categorized into intrinsic and extrinsic risk factors. Intrinsic risk factors are factors inherent in the individual, while extrinsic risk factors are environmental factors that interfere with the individual. Intrinsic risk factors can be further grouped into demographic factors (age, gender, race, tobacco use, history of previous MSK-I), anatomical factors (high arches and genu valgus), and physical fitness factors (low aerobic fitness, endurance, and strength; see Table 15.1). Extrinsic risk factors vary with the training environment. High running mileage, certain training companies, older running shoes, and the summer season have been identified as risk factors for overuse injury in Basic Combat Training (BCT) [9]. Injury prevention strategies for training-related injuries attempt to modify both intrinsic and extrinsic risk factors.

However, a recent paradigm shift in the conceptualization of risk factors has begun to focus on whether risk factors for MSK-I are “modifiable” or “non-modifiable.” Intrinsic and extrinsic risk factors, which may be interrelated and influence each other, whereas modifiable or non-modifiable risk factors allow for straightforward identification on specific risk factors that are amenable to change (i.e., modifiable) [10, 11]. In order to prevent MSK-I, it is critical to identify and focus on the modifiable risk factors associated with injury as these factors are likely amenable to intervention. As a result, classifying risk factors by whether they are modifiable or non-modifiable is much more relevant from a clinical and injury prevention perspective. Non-modifiable risk factors are important to help identify which populations are at greatest risk for injury so that prevention resources can be justifiably directed to these populations. However, as many intrinsic and extrinsic risk factors are in essence modifiable, they hold the most promise as targets for truly successful injury prevention interventions. Table 15.1 describes identified risk factors for training-related MSK-I across various categories and whether they are considered modifiable (M) or non-modifiable (N) .

Ankle sprains in the military occur at a rate of almost 35 sprains per 1000 person-years at risk—5 times the rate reported in civilian populations [25]. Therefore, prevention of ankle sprain has become a top priority. Ankle bracing has been shown to effectively prevent ankle injuries in several well-designed studies, especially in those who have had previous ankle sprains. A randomized controlled trial by Sitler et al. [26] on 1601 cadets at the United States Military Academy at West Point found that ankle brace use significantly reduced ankle injury during required intramural basketball. Cadets were randomized into a semirigid ankle stabilizer versus control group. They were then further randomized into a non-injured versus previously injured group and followed for 2 years. After 2 years, there were a total of 46 ankle injuries, 11 in the ankle stabilizer group and 35 in the control group (χ² = 12.29; P < 0.01). The ankle stabilizer group had a significantly lower rate of ankle sprains compared to the control group (1.6 per 1000 athlete exposures versus 5.2 per 1000 athlete exposures). Although there are always concerns from the athletes regarding performance decrement and comfort with ankle bracing, a recent study in military cadets looking at obstacle course times and dynamic lower extremity reach found no effect on performance with bracing compared to non-bracing [27].

Ankle bracing has also been shown to prevent ankle injuries related to parachuting. Results of a study by Shumaker et al. [28] found that during airborne jump operations, those wearing an outside-the-boot brace had 0.6 inversion ankle injuries/1000 jumps compared to 3.8 injuries/1000 jumps for those who did not wear the brace. This translated to three times fewer ankle injuries in Army Rangers when wearing braces [28]. According to a recent systematic review on the effectiveness of a parachute ankle brace (PAB) overall, not wearing a PAB approximately doubled the incidence of ankle injury, ankle sprain, or ankle fracture. In addition, the calculated cost-effectiveness of a PAB showed that for every $1 spent on the brace, $7–9 in combined limited duty and medical costs were returned—significant savings [29]. Overall, there appears to be a significant benefit to prophylactic bracing in preventing ankle injuries during airborne training and operations, particularly in the participants with a history of previous ankle injuries.

Specific programs that address increasing neuromuscular control, proprioceptive, and agility training have been shown to decrease anterior knee pain, stress fracture, and other lower extremity MSK-I incidences during military training [8, 12, 30]. Anterior knee pain, or patellofemoral pain syndrome (PFPS), is a common overuse injury in the military. In United States Naval Academy midshipmen, the prevalence of PFPS upon entry to the academy is as high as 15 % in females and 12 % in males. Female midshipmen develop PFPS at a rate of 33/1000 person-years (95 % CI = 20–45/1000 person-years), while males have a rate of 15/1000 person-years (95 % CI = 7–22/1000 person-years) [31]. In British Army recruits, an intervention of stretching and strengthening was found to reduce PFPS during entry-level training [30]. This randomized controlled trial compared the stretching and strengthening intervention (n = 759) to standard warm-ups (n = 743) during the 14-week basic training cycle. The eight intervention exercises were performed as a part of regular physical training and included isometric hip abduction against a wall in standing, forward lunges, single-legged step downs, single-legged squats, quadriceps stretching, iliotibial band stretching, hamstring stretches, and calf stretches. Most importantly, an emphasis was placed on form. In total, 46 cases of diagnosed anterior knee pain were reported: 36 (4.8 %) in the control group and 10 (1.3 %) in the intervention group (P < 0.01). Surprisingly, there were no gender differences noted. Perhaps, the most significant finding from this study was that despite a PFPS diagnosis, the training completion rate for those from the intervention group was 90 %, while only 44 % of the PFPS cases in the control group successfully completed the training [30].