Among the large variety of athletes, ankle sprains are one of the most
common musculoskeletal injuries. According to research, a considerable amount
of sports-related injuries may be caused due to ankle instability, also known
as ankle ligament laxity.
Factors for Ankle Sprains
The most frequent factor behind a majority of ankle sprains is when a
single extremity lands on an uneven surface. During this case, a quick and
joined ankle plantar flexion and inversion motion can often result in an
extreme lateral movement which can lead to ankle sprains. Another factor that
can influence the chance of lateral ankle sprains is proprioception, or an individual’s
own neuromuscular control. With the necessary proprioception, an athlete may be
able to accurately determine the speed and force of a disturbance of motion in
order to be able to subsequently react with an appropriate joint and muscle
motion to avoid injury. However, because there’s always a chance the athlete
may be surrounded by uneven terrain, even an individual with excellent proprioceptive
skills can suffer harm. Moreover, the evidence for the role of proprioceptive
factors in preventing ankle sprains is still unclear. Other factors which may
lead to ankle sprains among athletes included non-modifiable risk factors such
as: sex, age, height, race, foot/ankle anatomy, extremity alignment, previous
ankle sprain and generalized joint laxity. Modifiable risk factors that can
cause an ankle sprain include: weight, body mass index, bracing/taping,
footwear, neuromuscular control, postural stability, muscle strength, exposure
to sport, player position, playing surface and skill level.
Due to the nature of lateral ankle sprains, once an individual has
experienced an injury, there’s a high probability that another injury can
occur. This is because damage or injury to the ligaments and joint capsules
within the ankle can impair the structures ability to function appropriately. Along
with any deficits in proprioception, this can often result in a high re-injury
rate. Indeed, research has demonstrated that 73 percent of individuals who
sprain their ankles are most likely to experience recurrent ankle injuries in
the future.
The Importance of Balance
As
previously mentioned, numerous researchers have proposed that both neuromuscular
control and proprioception of the ankle joint is a considerable factor in the initial
and recurrent cause of ankle sprains. Furthermore, despite decades of studies
on ankle sprains, the evidence remains inconclusive. More specifically,
research has failed to find actual evidence that suggests individuals with
ankle instability may experience proprioception deficits compared to those
without a history of ankle instability because there is no standard testing and
training protocol for determining ankle proprioception.
Many healthcare professionals believe that balance issues and an impaired
proprioception can play a significant role when it comes to ankle sprains. These
are common components of many intervention programs for the prevention and
treatment of acute lateral ankle sprains and chronic ankle instability.
Moreover, a considerable amount of contemporary theory on this subject suggests
that balance and coordination training may have both local and central effects on
the sensorimotor system, or a subcomponent of the comprehensive motor control
system of the body.
In a 2008 review study performed to provide a better understanding
behind proprioception, balance and ankle sprain, the following questions were
issued to answer various doubts regarding the issue:
1. Can prophylactic balance and coordination training reduce the chance
of experiencing a lateral ankle sprain?
2. Can balance and coordination training improve the result of
treatments associated with acute ankle sprains?
3. Can balance and coordination training improve the result of
treatments in patients with chronic ankle instability?
In total, the results of eleven studies were combined; three of which
were used to answer question 1, three to answer question 2 and five to answer
question 3. The researchers finally determined that prophylactic balance and
coordination training essentially reduced the chance of athletes suffering
ankle sprains, more closely observed among those with prior sprains. There was
also further evidence that completing at least 6 weeks of balance and
coordination training during recovery from an acute ankle sprain could
potentially reduce the risk of frequent ankle sprains for up to one year.
Although a variety of studies determined the above facts, the
researchers also noted that the improvements in the postural control
instrumented measures associated with the training were not regularly calculated
from study to study, which ultimately reduces the quality of the evidence. They
also mentioned that there was not enough evidence to accurately assess the
reduction in the chance of experiencing repeated sprains, inconclusive to
demonstrate improved instrumented postural control measures and limited towards
the development of an athlete’s functions with chronic ankle instability or
ankle ligament laxity who also complete balance and coordination training.
The findings of the above study were also relevant with a very recent
study regarding ankle sprains among the athletic population. This study
recognized that a change in neuromuscular control as a result of peripheral
proprioception alterations of the ankle joint may in fact contribute to the
high frequency of lateral ankle sprains and that after the initial injury,
overstretched and/or loosened ligaments and joint capsules may restrict the
function of the mechanoreceptors in those structures. It also demonstrates that
some researchers have reported prolonged peroneal muscle reflex latency in
injured ankles and ankle position sense deficits in various testing protocols.
However, the researchers from the study also showed that regardless of
the provided evidence, there are also many studies which have been conducted
that contradict these findings. For instance, in several studies that compare
healthy and unstable ankles, no peroneal reflex latency differences, no
position sense differences, and no movement sense differences were found between
the two various ankles studies. Additionally, some studies indicate that the ability
to sense ankle position is not recommended to be used for predicting ankle
sprains in the future.
Strength and Balance
With that mentioned, a majority of the provided evidence appears to be
contradictory, at least in the sense where balance training is not believed to
improve the prediction of ankle sprains and reduce the risk of repeated injury,
regardless if there’s a small amount of evidence that shows how improving an
individual’s neuromuscular control can produce positive results. This could be
because even with better, almost intact proprioception at the ankle joint,
generating enough muscle strength that is fast enough to counter the wide
variety of quick disturbances of motion, such as landing on an uneven surface,
still remains an issue.
One likely consideration for the examination is the role of strength. A
recent study has indicated that developing sufficient muscle strength could
indeed play a much more essential role in the prevention and rehabilitation of
ankle sprains rather than improving proprioception. Although the effects of
muscle strength on ankle stability is yet unclear, muscle weakness has been
reported in peroneal muscles, ankle dorsiflexes, and hip abductors among many
individuals with ankle instability.
Although stimulating large muscles can enhance the sensitivity of muscle
spindles, strength training is not proven to reduce the chance of initial and recurrent
ankle sprains through enhancing neuromuscular control of the ankle joint. It
can help restore ankle muscle balance, however, as well as better position the
ankle and increase the strength of the ligaments. In addition, a larger and stronger
muscle can also provide additional passive restraints to the ankle joint.
Therefore, if balance training is beneficial in reducing ankle sprains,
it is most likely because of the enhanced strength and stiffness in both
muscles and ligaments at the ankle joint rather than enhanced neuromuscular
control. In other words, while improving neuromuscular control and
proprioception at the ankle joint may not be effective towards protecting the
ankle from an accident, balance training can increase the strength of muscles
and ligaments around the ankle joint. Since ligaments are the primary stabilizer
of the ankle joint, treatment protocols with a balance training routine may
benefit the athletes with unstable ankles.
In conclusion, it appears that ankle injury prevention and rehabilitation
programs which focus primarily on proprioception improvement may not be as
effective after all. The evidence that proprioceptive training can benefit the
prevention of an injury or recurrence is not considered to be strong enough.
However, the evidence for balance training is much stronger, although the
benefits are most likely to occur as a result of improvements in muscular and
ligament strength.
Preventing Sports Injuries
By Dr. Alex Jimenez