Proprioceptive exercises balance ankle stability and activity

[Guest guest]

October 2006 Biomechanics Magazine

http://www.biomech.com/showArticle.jhtml?articleID=193200662

Proprioceptive exercises balance ankle stability and activity

The combination of exercises may reduce the chance of recurrent

ankle sprains and reinjury.

By: L. Ross, ATC, CES

Chronic ankle instability, usually a result of recurrent sprains, is

an ongoing problem, especially among active individuals. According

to Holme et al,1 lateral ankle sprains are common and account for

nearly 15% of all sports injuries. Ankle sprains vary in severity

and consequential disability based on the degree to which the

ligaments are damaged. In most cases, ankle sprains are graded as

mild, moderate, or severe.2 The incidence of recurrent ankle sprain

is high and leads to further ligamentous damage as well as damage to

the mechanoreceptors.3 Long-term effects of repetitive ankle trauma

leave an individual more susceptible to degenerative changes.3

Because of the degenerative changes and a reduction in

proprioceptive awareness, a correlation to postural instability may

exist,4 leading to a sense of not being coordinated and a loss of

movement control. In order for an ankle to have control, muscles and

nerves must function synergistically. If there is a deficiency in

any area, a perceived sense of instability may be noted. An altered

sense of balance will heighten functional ankle instability because

of increased movement at the body's periphery, away from the center

of gravity.5

Proprioception is defined as the ability to establish a sense of

position in space, especially at a joint.2 Kinesthesia means to

detect movement.2 Both of these functions are associated with the

joint mechanoreceptors and are interrelated. If the mechanoreceptors

are damaged when an ankle sprain occurs, proprioception will be

affected, which results in a reduction in the body's ability to

balance. Thus, proprioception will not be an effective mechanism for

reducing the chance for further injury. ucation of the

mechanoreceptors becomes a vital key to returning an individual to a

perceived sense of stability.

Based on clinical experience, the majority of physical therapy

clinics and athletic training rooms incorporate both strengthening

and proprioception exercises to return patients and clients to

activities of daily living or competitive athletics. Numerous

studies have looked at the effects of strengthening exercises,

proprioceptive exercises, or a combination of both on returning a

patient to functional activity.6-11 Methods of proprioceptive

rehabilitation include single leg stance and ankle disk training.

Both help to improve the neuromuscular control in the patient,

client, or athlete, which results in a reduced likelihood of future

ankle sprains.

Single leg stance

The single leg stance exercise is one of the mostly commonly used

techniques for increasing proprioception. Single leg stance requires

the individual to balance on one leg, generally without additional

support. During rehabilitation, this method is used both for a

baseline measurement of balance and to progress patients as they

recover. A level of progression might be to take away vision (eyes

closed), making the single leg stance more difficult. As a person

progresses through various techniques, the single leg stance can be

made more challenging by changing surfaces and other ambient

factors. Throughout the literature, the single leg stance has been

used in conjunction with other rehabilitation and proprioceptive

techniques. No specific study published between 1995 and September

2005 and available on PubMed or EBSCO has looked solely at the

effectiveness of single leg stance. On the other hand, single leg

stance appears to have been a key element in every proprioceptive

program reviewed.

Ankle disk training

An ankle disk, commonly used in research studies,6-11 is generally

described as a circular platform with a half ball underneath used

for balancing exercises. The exercises might involve using one or

two legs to move the disk in multiple directions. The ankle disk is

used to move an individual's ankle or ankles (single leg or double

leg stance) through dorsiflexion/plantar flexion,

inversion/eversion, and clockwise/counterclockwise directions.

Because of its circular design, the ankle disk allows for

multiplanar movement and a wide variety of exercises.

Ankle disk training has been shown to help improve balance in a

single leg stance.6-11 Studies have been performed using both

healthy7,10 and previously injured6,8 subjects to determine the

effectiveness of the device. Sheth and colleagues10 used healthy

subjects to simulate an ankle sprain and assess its effects on

various muscles. After eight weeks of training with the ankle disk,

the subjects showed improvement in muscle contraction that may

reduce the chance of a lateral ankle sprain. An earlier study by

Hoffman and Payne7found significant improvements after using the

ankle disk three times per week for 10 weeks on healthy subjects.

Both studies used reproducible research methods. Hoffman and Payne

used stabilometry recordings to determine how well an individual can

balance, while Sheth and colleagues used fine-wire electrodes to see

how quickly muscle contractions occur.7,10 Although different in

design, the aims of both studies were similar: to determine the

increased neuromuscular control and proprioception benefits of ankle

disk training for a healthy subject.

Studies have also been conducted to determine the effectiveness of

ankle disk training in helping to reduce the chance of further

injury for patients with previous ankle sprains. Eils and Rosenbaum

used a multistation proprioceptive training program, including ankle

disk training, for a period of six weeks.6 They looked at postural

sway, joint position sense, and muscle reaction times and found

significant improvements in plantar flexion angle of reproduction

and all aspects of postural sway and a slight increase in muscle

reaction times after completion of the training program. Slightly

more comprehensive in the number of exercises used for its

proprioceptive exercise program, this study did involve the ankle

disk and overall results were favorable.

Another study used electromyographic (EMG) recordings to determine

muscle onset latency.8 The procedure used was identical to that of

Sheth and colleagues, but the subjects were individuals with a

history of ankle sprains. They used the ankle disk for a period of

eight weeks before being retested. The results showed a significant

decrease in the muscle onset latency of the anterior tibialis,

peroneus longus, flexor digitorum longus, and posterior tibialis.

This study shows that an ankle disk program can be effective in

decreasing muscle onset latency in particular muscles after ankle

sprain.

Most research involving ankle instability has been done within a

clinical setting. Stasinopoulos conducted a study on Greek female

volleyball players. The study involved three interventions:

technical training, proprioceptive training on a balance board, and

use of a sport-stirrup orthosis.12 Players who had experienced an

ankle sprain during the 1998-1999 season were included in the study

during the 1999-2000 season. Randomly assigned to one of the three

interventions, the players followed their respective program for the

entire season. The proprioceptive group had three ankle sprains

among 17 subjects. Results of the study showed that each of the

three preventive methods was effective at reducing the number of

ankle sprains reported.

Ankle disk training, based on evidence from some of the studies

cited, can help improve various aspects of balance and muscle

reaction time. The long-term effects of this proprioceptive training

technique, however, are not known. Stasinopoulos looked at injury

rates over an entire season, but would the numbers improve over a

second or third year of continuous proprioceptive training? Further

research is needed to determine whether ankle disk training will be

effective over an extended period of time or whether additional

methods need to be added as an individual becomes competent in

performing the given technique.

Clinical implications

Studies involving lower leg proprioception play a key role in the

implementation of programs for those with stable and unstable

ankles. The majority of research indicates that proprioceptive

training is effective at developing better balance and reducing the

chance of further injury.5-8,10-13 Studies have shown that balance

and coordination training reduce the chance of recurrent ankle

sprains.6-8,10,11 However, other studies indicate that

proprioceptive exercise may not be effective at reducing the chance

of an ankle sprain.3,9

The goal behind proprioceptive exercises is to help the patient

restore stability and neuromuscular control. Fu and Hui-Chan looked

at recurrent ankle sprains among basketball players and their effect

on postural sway and found that as the number of ankle sprains

increased, so did the number of errors in ankle positioning and

postural sway.4 They concluded that there was a need for

rehabilitation and proprioceptive training among those with

recurrent ankle sprains. Unfortunately, only a few studies have used

EMG to look at how well the neuromuscular system works in preventing

or reducing acute or chronic ankle sprains.3,6,7,10 The majority of

these studies found improvement in muscle reaction time as it

related to an induced ankle sprain;6,7,10 however, there is not

enough research from which to draw a conclusion. More studies are

needed to show the overall benefits of proprioceptive exercise for

both the stable and unstable ankle.

Conclusion

Chronic ankle instability, sometimes associated with multiple ankle

sprains, can lead to difficulty with walking, running, jumping, and

cutting. Although functional instability can lead to impaired

performance, the literature shows that proprioceptive exercise may

help with overall balance. The combination of rehabilitative and

proprioceptive exercises has been shown to decrease the chance of

recurrent ankle sprains as well as reduce the chance of reinjury in

a functionally stable ankle. The most common methods of training

include single leg stance and the ankle disk. Individually or in

combination these exercises and devices help improve ankle

stability. This suggests that proprioceptive deficiencies can be

improved through a variety of balance exercises that help to

increase muscle reaction time and the contraction patterns that

favor the correction of excessive inversion.10

Future research

The literature suggests that proprioceptive exercise is beneficial

for increasing functional ankle stability. However, a few articles

dispute the effectiveness of proprioceptive exercise.3,9 They

suggest that the training period in some studies may not have been

long enough to show the effectiveness of proprioceptive exercise.

Also, further research needs to be conducted under different

parameters. The difficulty with this approach is compliance and

accuracy. Stasinopoulos, the author of a study on professional women

volleyball players in Greece, suggested that more research was

needed to look more closely at male volleyball players.12 Studies

looking at young soccer players might need to look further at older

players.13 These studies have helped to demonstrate the

effectiveness of proprioceptive exercise, but more needs to be done

in a variety of settings to show overall effectiveness.

Research is an ongoing endeavor resulting in new methods of

rehabilitation that are being tried every day. Proprioceptive

exercise is one of the newer benefits available in rehabilitation.

With every new study that is completed, physical therapists and

athletic trainers are able to provide better care to their patients.

In the future, it is likely more studies will indicate that

proprioceptive exercise, along with rehabilitation and

strengthening, will help a patient return to activity with a

stronger, more functionally stable ankle.

L. Ross, MS, ATC, CES, is the athletic trainer at Konawaena

High School in Kealakekua, HI.

References

1. Holme E, Magnusson SP, Becher K, et al. The effect of supervised

rehabilitation on strength, postural sway, position sense and re-

injury risk after acute ankle ligament sprain. Scand J Med Sci

Sports 1999;9(2):104-109.

2. Arnheim DD, Prentice WE. Principles of athletic training. Boston:

McGraw-Hill, 2000:492-496.

3. Powers ME, Buckley BD, Kaminski TW, et al. Six weeks of strength

and proprioception training does not affect muscle fatigue and

static balance in functional ankle instability. J Sport Rehabil

2004;13(3):201-227.

4. Fu AS, Hui-Chan CW. Ankle joint proprioception and postural

control in basketball players with bilateral ankle sprains. Am J

Sports Med 2005;33(8):1174-1182.

5. Blackburn T, Guskiewicz KM, Petschauer MA, Prentice WE. Balance

and joint stability: the relative contributions of proprioception

and muscular strength. J Sport Rehabil 2000;9(4):315-328.

6. Eils E, Rosenbaum D. A multi-station proprioceptive exercise

program in patients with ankle instability. Med Sci Sports Exerc

2001;33(12):1991-1998.

7. Hoffman M, Payne VG. The effects of proprioceptive ankle disk

training on healthy subjects. J Orthop Sports Phys Ther 1995;21

(2):90-93.

8. Osborne MD, Chou LS, Laskowski ER, et al. The effect of ankle

disk training on muscle reaction time in subjects with a history of

ankle sprain. Am J Sports Med 2001;29(5):627-632.

9. Riemann BL, Tray NC, Lephart SM. Unilateral multiaxial

coordination training and ankle kinesthesia, muscle strength, and

postural control. J Sport Rehabil 2003;12(1):13-30.

10. Sheth P, Yu B, Laskowski ER, An KN. Ankle disk training

influences reaction times of selected muscles in a simulated ankle

sprain. Am J Sports Med 1997;25(4):538-543.

11. Verhagen E, van der Beek A, Twisk J, et al. The effect of a

proprioceptive balance training program for the prevention of ankle

sprains [electronic version, PubMed]. Am J Sports Med 2004;32

(6):1385-1393.

12. Stasinopoulos D. Comparison of three preventive methods in order

to reduce the incidence of ankle inversion sprains among female

volleyball players. Br J Sports Med 2004;38(2):182-185.

13. Malliou P, Gioftsidou A, Pafis G, et al. Proprioceptive training

(balance exercises) reduces lower extremity injuries in young soccer

players. J Back Musculoskeletal Rehabil 2004;17(3-4):101-104.