Page 136 - JSOM Summer 2022

articles relating to injuries during OCEs. Keywords used in the US Military Academy (West Point) in 1858, but the first obsta-
search were injury OR illness AND obstacle course. The refer- cle course for general Army testing was part of an “Individual
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ence lists of the obtained articles were also examined for other Efficiency Test” conducted during the WWI period. This test
articles that were missed by the formal search. Articles were consisted of 6 events including a 100-yard run, running broad
included in the review if they reported quantitative data on jump, wall climb (8 feet), hand grenade throw (30 yards,
injuries or illnesses experienced during any type of OCE, were 10-foot square to hit), and the obstacle course. The obstacle
written in English, and were published in peer-reviewed jour- course itself was a 100-yard linear track with six obstacles: (1)
nals. During the course of the review, studies were found relat- vaulting a 3-foot hurdle; (2) negotiating a 10-foot wire entan-
ing to infection outbreaks during OCEs. Since this appeared to glement (arms folded); (3) climbing a 5-foot ramp; (4) jumping
be an important hazard, the review was expanded to include from the top of the 5-foot ramp over a 10-foot trench; (5) ne-
studies of this type. To guide the data extraction, a spreadsheet gotiating a 1-foot wide, 20-foot-long plank; and (6) climbing
was constructed that contained the study name; type of OCE; an 8-foot, smooth-faced wall. Soldiers sprinted 10 to 15 yards
how data was collected; total participants; number of partic- between each obstacle and at the start. 29
ipants with medical problems; number of medical problems
evacuated by ambulance and by private vehicles; referrals to Obstacle courses are still common in US Army training. Ver-
participant medical care providers; types of medical problems; sions of Army Field Manual (FM) 20-21 (Physical Fitness
and anatomical location of injury. In some cases, these data Training) 30,31 and FM 7-22 (Physical Readiness Training/Holis-
were not available in particular investigations, but as long as tic Health and Fitness) 32,33 contain information on confidence/
data was provided on the number of medical problems during obstacle course construction, negotiation, and safety. Civilian
an OCE the study was included in the review. The final search OCE can contain obstacles similar to their military counter-
was completed in February 2022. parts involving activities like climbing objects and netting,
vaulting/stepping over barriers, climbing up and down lad-
The Comprehensive Meta-Analysis Statistical Package, Version ders, balancing on logs, descending on ropes, climbing walls,
3.2 (Biostat, Englewood, New Jersey, US) was used to perform low crawls under nets/wires, and other activities.
meta-analyses on four variables available in many studies.
These variables included total medical encounters, ambulance There are several case studies of military personnel experienc-
evacuations, personal vehicle evacuations, and referrals to per- ing lower body fractures and dislocations on military obstacle
2
sonal medical care. For total medical encounters, data in the courses. 15–18 A study at Ft Leonard Wood Missouri, exam-
meta-analysis included the total number of participants and ined all injuries occurring during Initial Entry Training (IET).
the number that experienced medical problems of any type. Medical personnel were present during all training activities
For ambulance evacuations, personal vehicle evacuations, to treat and record medical problems. The confidence/obstacle
and referrals to personal medical care, the data in the meta- course accounted for only 5% of all IET injuries. However,
analyses include the total number of cases and the overall num- when investigators considered the estimated amount of actual
ber of medical cases of any type. The meta-analyses produced training time on the course, the confidence/obstacle course
an effect size for each of these four variables with their 95% had the highest injury rate of all training activities at 97 inju-
confidence intervals (95% CI). The effect size represented the ries/hour of training. This was followed by physical training at
weighted and pooled results from all individual investigations. 62 injuries/hour and foot marching at 13 injuries/hour.
A random-effects model was used for all analyses. Heteroge-
2
neity in the individual studies was assessed using the Q- and Another study examined medical encounters during the US
the I -statistics. Heterogeneity was the degree of variability Army Special Forces Assessment and Selection (SFAS) course.
2
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2
among the individual studies. For I , values could range from 0 Again, injuries on the obstacle course accounted for only 5%
to 100 with higher numbers indicating more variability. of all injuries during the 19- to 20-day course; however, when
researchers considered the estimated time in each training ac-
tivity the injury rate for the obstacle course was the highest
Results
at 65 injuries/hour of training. This was followed by running
Three retrospective studies 2,13,14 and 4 case studies 15–18 were at 27 injuries/hour, Combat Readiness Assessment (activities
found involving injuries during military obstacle course train- involving combat-related tasks) at 20 injuries/hour, and foot
ing. Civilian studies on medical events during OCEs were marching at 16 injuries/hour. These two studies 2,13 indicate
largely focused on medical encounters seen by medical care that of all training/assessment activities, obstacle courses have
providers at medical tents located on the event course or en- the highest injury rate of all common training activities in IET
counters with medical personnel stationed along the OCE and during the SFAS course.
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course. 6,19–24 Exceptions were 1) a study providing a case
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series and other encounters at one emergency department of A final study examined anterior cruciate ligament injuries
a hospital after a OCE and 2) an on-line survey that asked among US Naval Academy cadets during a 6-year period. The
participants about upper and lower limb injuries during OCE authors reported that during running of obstacle courses the
events. There were two studies of infection outbreaks during incidence rate for anterior cruciate ligament injury was 6.1 vs
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OCE. 27,28 Once it became apparent that the infection out- 0.6 cases/1000 obstacle course exposures for women and men,
breaks were associated with infected mud or muddy water, respectively.
the review was expanded to examine other outdoor events in
muddy conditions where infections were encountered. Medical Encounters During
Civilian Obstacle Course Events
Injuries on Military Obstacle Courses Table 1 shows data from eight studies examining medical en-
Military obstacle courses have been a part of Army training counters during civilian OCEs. Half of the studies 6,19,20,25 did not
for a long time. An early one was used for testing cadets at the have the exact number of participants, but provided estimates.

132 | JSOM Volume 22, Edition 2 / Summer 2022