Page 114 - JSOM Winter 2019

Army adopted optional use of the brace for all airborne oper- airborne students after they completed their fourth of the five
ations and described the use of the PAB in Army Field Manual jumps necessary to become airborne qualified. Among stu-
(FM) 57-220 (Static Line Parachuting Techniques and Train- dents who wore the PAB, 48% had a favorable opinion, 49%
ing). The US Army Airborne School began using the PAB in had a negative opinion, and 4% were neutral. Another study
24
28
1994. A subsequent study at conducted between November conducted in 2014 involved 100 soldiers with an average of
1994 through December 1996 at the 3d Ranger Battalion at Ft 4 years on jump status who were training to be jumpmasters
Benning, GA, showed that ankle injuries were substantially re- at the Advanced Airborne School at Ft Bragg, NC. Only 38%
duced among Rangers wearing the PAB compared with those of students had heard of the PAB, and among those, 54% had
not (4.5 vs 1.5 ankle injuries/1000 jumps, RR [braced/not concerns that would prevent them from using the PAB. Among
braced] = 0.34, 95% CI = 0.16–0.71). 25 students with a prior ankle sprain, 54% reported being some-
what or very likely to use some form of ankle bracing. 31
Despite these positive outcomes, PAB use was discontinued at
the US Army Airborne School in 2000 because of (1) the cost In summary, data from six scientific studies involving
of maintaining the brace, (2) anecdotal reports that the brace >1,300,000 jumps and two systematic reviews indicated that
increased injuries in other parts of the lower body, and (3) an- the PAB reduced ankle injuries and ankle fractures by about
ecdotal reports that the brace complicated parachute entangle- half with a return on investment of at least 7:1. These studies
ments. After the PAB was discontinued at the Airborne School, were conducted when the Army was using the T-10D para-
a study was conducted to compare injuries among students chute; the injury reduction efficacy of the PAB has not been
while the PAB was in use versus after it was discontinued. It tested with the newer T-11 parachute or with the newer mili-
was found that the risk of an ankle injury hospitalization due tary boots. Although the 2013 edition of FM 3-21.220 (Static
to parachuting was 1.65 (95% CI = 1.22–2.24) times higher Line Parachuting Techniques and Training) still listed the PAB
after the PAB was discontinued. 26 as an optional item of equipment for parachutists, the latest
version does not. DJOrtho no longer manufactures the PAB
32
In 2004, the effectiveness of the PAB was brought to the at- shown in Figure 5 and recommends the Aircast Model A60 .
®
tention of the Defense Safety Oversight Council (DSOC). The Model A60 is an inside-the-boot brace worn directly on
The DSOC requested a determination of whether the PAB the foot (over the socks) and has not been tested in airborne
increased injuries in other parts of the lower body and com- operations.
plicated parachute entanglements. At the end of a 21-month
project involving >100,000 jumps, it was found that airborne FIGURE 5 The parachute ankle brace.
27
students not wearing the PAB were almost twice as likely to
experience an ankle injury compared with those who did wear
the brace (RR = 1.92, 95% CI = 1.38–2.67). Further, there
was no significant increase in other lower body injuries exclu-
sive of the ankle (14 injuries/10,000 jumps in PAB group vs
13 injuries/10,000 jumps in the non-PAB group, p = .62) and
no significant differences in parachute entanglements in which
students remained entangled to the ground (4/10,000 jumps in
PAB group vs 5/10,000 jumps in non-PAB group, p = .73).
27
In 2007, the use of the PAB was reinstituted at the Airborne
School, but the new commander in 2009 discontinued use, be-
cause of a perceived increase in the number of ankle injuries.

Later studies also demonstrated that the PAB reduced ankle
injuries in airborne operations. 28,29 In 2010 and 2016, two sys-
tematic literature reviews of PAB injury studies was conducted.
Meta-analyses that pooled the data from 5 studies indicated
that among paratroopers ankle injuries, ankle sprains and
ankle fractures were 2.13 (95% CI = 1.80–2.53), 2.07 (95%
CI = 1.40–3.08), and 1.77 (95% CI = 1.07–2.94) times higher, Summary
respectively, when the PAB was not used. A cost-effectiveness
analysis indicated that for every $1 spent on the PAB, there Injuries during military airborne operations have decreased
was a savings of $7 to $9 in medical and lost duty day costs. over time. At the Airborne School, some of the innovations
30
1
The other meta-analysis excluded one study reviewed in the associated with this decrease include improved ground landing
16
earlier meta-analysis that included self-reported injuries, but techniques (especially the PLF), better supervision of Soldiers
30
it included one study not available at the time of the earlier while in initial airborne training, and elimination of unnec-
16
review. The 2016 meta-analysis concluded that those not wear- essary training procedures (like jumps from 11-foot heights)
ing the PAB had 1.84 (95% CI = 1.63–2.08) times the risk of an that resulted in high injury rates. Aircraft exit techniques that
ankle injury compared with those wearing the PAB. 16 have reduced injury rates include alternating jumps between
the two aircraft doors so that the jumpers exit at slightly dif-
Attitudes of paratroopers toward the use of the PAB are im- ferent times (CAPES) and possibly the procedure in which the
portant because the PAB is an extra item of equipment that jumper grasped the reserve parachute rather than the aircraft
must be properly worn and checked, in addition to the other door when exited the aircraft. Equipment innovations in-
equipment paratroopers must be concerned with. During cluded improvements in parachute technology, especially the
2005 and 2006, a questionnaire was administered to 1,677 T-11 parachute that reduced overall injuries by about 43%

112 | JSOM Volume 19, Edition 4 / Winter 2019