|Year : 2017 | Volume
| Issue : 1 | Page : 14-21
Does balance training balance the functional aspects of ankle instability?
Zafar Azeem1, Kalpana Zutshi2
1 Department of Physiotherapy, Charotar University of Science and Technology, Anand, Gujarat, India
2 Department of Physiotherapy, Faculty of Allied Health Sciences, Jamia Hamdard, New Delhi, India
|Date of Web Publication||3-Jan-2017|
Department of Physiotherapy, Charotar University of Science and Technology, Petlad, Anand - 388 421, Gujarat
Background and Purpose: Ankle sprains are the reigning top most priority in the management and prevention of sports injuries. However, the repetitive nature of the injury makes it difficult to prevent as the functional deficits disturb the kinesthetic sense and thereby functional movement performance indicators of sportsmen. Balance training is considered as the mainstay of preventive strategy for ankle sprains though limited evidence seems to suggest the actual mode of training. This study was aimed to study the efficacy of wobble board training and a new functional balance training program on athletes with recurrent ankle sprains and reported functional deficits in the injured or affected leg. Materials and Methods : The training was carried out for 30 recreational athletes with a history of "giving away" and atleast 1 ankle sprain during the past 6months. Static and dynamic postural control were assessed using measures of balance in static and dynamic mode. Results: The results of the study showed that both training programs showed equal benefits in improving the static and dynamic postural control though functional training had more impact due to its functional nature of movements. Conclusion: The findings from our study pointed toward the greater need to involve function oriented movement approach to prevent sporting injuries as frequent and common as ankle sprains.
هل تنظم تمارين التوازن الجانب الوظيفي لعدم استقرار الكاحل
الخلفية: التواءات الكاحل لها الاولوية العليا التي تحكم الوقاية والعلاج في الإصابات الرياضية. إلاّ أن تكرار الإصابة يجعل من الصعب تجنب الخلل الوظيفي الذي يصيب الإحساس في العضلات والأوتار العضلية ومؤشرات أداء الحركة الوظيفية لدى الرياضيين. وتعدّ تمارين التوازن من إسترتجيات الوقاية السائدة في التواء الكاحل رغم محدودية الدليل التي تقترح طريقة التمرين.
هدف الدراسة: دراسة فعالية تمرين لوح التأرجح وبرنامج التمرين الوظيفي المتوازن الجديد على الرياضيين المصابين بالأتواء كاحل حديث مع خلل الوظيفي بالرجل المصابة او المتأثرة.
المواد والطريقة: تم إجراء التمرين لثلاثين من الرياضيين الذين كانوا في حالة استجمام والذين لديهم تاريخ من الاعتزال وعلى الأقل التواء واحد بالكاحل خلال الأشهر الستة المنصرمة. تم التقييم في وضعية الثبات والحركة باستخدام قياس التوازن في وضع الثبات والحركة.
النتائج: أظهرت نتائج الدراسة أن تعادل فوائد برنامجي التدريب في تحسن التحكم في وضعية الثبات والحركة على الرغم من الاعتقاد أنّ للتمرين الوظيفي تأثيراً أكبر نظراً لطبيعته الوظيفية في الحركات.
الخلاصة: أشارت نتائج الدراسة أن هناك حاجة كبيرة لإدخال وسيلة التنوير الوظيفي للحركة لتجنب الإصابات الرياضية المتكررة والشائعة مثل التواءات الكاحل.
Keywords: Ankle sprains, balance, balance training, functional ankle instability
|How to cite this article:|
Azeem Z, Zutshi K. Does balance training balance the functional aspects of ankle instability?. Saudi J Sports Med 2017;17:14-21
|How to cite this URL:|
Azeem Z, Zutshi K. Does balance training balance the functional aspects of ankle instability?. Saudi J Sports Med [serial online] 2017 [cited 2017 Aug 20];17:14-21. Available from: http://www.sjosm.org/text.asp?2017/17/1/14/197463
| Introduction|| |
Participation in athletics often leads to increased susceptibility to ligamentous injuries. Ankle sprains were the most commonly diagnosed injury in NCAA athletics between 1988 and 2004. In a similar study of men's and women's professional basketball players from 1996 to 2002, lateral ankle sprains were the most commonly diagnosed injury at 13.7%. Sprains affecting the lateral ligament complex of the ankle constitute 85-95% of ankle sprains in high school athletes.
In general, ankle sprain or ankle injury essentially indicates that lateral ligament complex of ankle joint including anterior talofibular ligament, calcaneofibular ligament, and posterior talofibular ligament are stretched or torn during an unanticipated or unprovoked plantarflexion, supination, and inversion movement of fixed foot coupled with external rotation of tibia.
The need to address proprioception following injury to the ankle ligaments was recognized in the 1960's. Rehabilitation in an attempt to improve neuromuscular control of the injured ankle should address the restoration of the control of volitional contractions of the muscles acting on the ankle, normal reflex responses, and normal pattern generated movements of the lower extremity. The multifaceted musculoskeletal system offers various ways that proprioception can be affected. Deficits in proprioception have been demonstrated after injury and with articular disease and increasing age. As joint moves, impulses must arise from muscular, fascial, tendon, and articular receptors. Injury to any or all of these receptors can result in a sensory deficit. Freeman et al. were the first to report that exercises on a wobble board (ankle disk training) could reduce the incidence of instability after ankle sprain as measured with a modified Romberg test. Since then, various methods have been used to assess the function of postural stability before and after ankle injury.
In spite of all the available methods of preventive strategies such as braces, taping, and orthotics, there is a tendency for athletes to go back to or be put back on the playing field as soon as they can tolerate activity despite their inadequate functional recovery. As the rehabilitation process continues, clinicians progress athletes to performing functional exercises that simulate joint motions the athletes will perform during athletic activities.
Creating a device that would increase the difficulty of performing functional exercises may prove to be more beneficial in improving postural stability than traditional wobble board exercises.
Although the research in the area of injury prevention is rather extensive, the most important data based on randomized controlled trials designed to address the effectiveness of an intervention in the prevention of ankle sprains are limited in both scope and rehabilitation.
Therefore, the purpose of our study was to make use of functional balance training program with balance shoes in cases with functional ankle instability and compare its efficacy to the traditional ankle disk program.
| Materials and Methods|| |
Design of the study
The study was a pretest and posttest experimental design which compared the effects of functional balance training and wobbles board training in cases with functional ankle instability on single leg stance test and Star Excursion Balance Test (SEBT) over a period of 4 weeks.
Cases were 30 recreational athletes (age 24.3 ± 1.2 years, weight 64 ± 6.72 kg and height 163.6 ± 4.51 cm) that were recruited for the study using convenience sampling based on inclusion criteria. This included 23 males and 7 females. Cases were then divided into functional balance training and wobble board training randomly based on lottery method. Cases were included in the study based on the history of recurrent episodes of ankle sprains (at least 1-3 before 6 months of the study) and self-reported feeling of "giving way" at the ankle joint during sports activities such as jumping, lateral cutting, and squatting., Cases were recruited only after obtaining the informed consent to participate in this study.
The dependent variables were measures of static and dynamic postural control with help of single leg stance test (eyes closed and open) and Star Excursion Balance Test respectively. The independent variables were functional balance training and wobble board training programs.
All the data for dependent variables were measured on three occasions, i.e. before starting of training, after 2 weeks, and after 4 weeks of training.
Before recording measurements for the pretest and posttest on the single leg stance test and Star Excursion Balance Test, cases were explained each test and each test was demonstrated to them. They were then asked to perform three practice trials on each of the tests for the dominant lower extremity.
For the single leg stance test, cases were instructed to place their foot fixed surface where they could best maintain a single leg stance with their arms placed on their hips both in eyes open and closed for a maximum period they could maintain their stance position. Three trials were taken for the testing and the average of the three trials was considered as static balance scores.
For the Star Excursion Balance Test (dynamic balance), cases were instructed to stand in the center of the star grid, which was laid on the floor with eight lines extending at 45° increments from the center of the star grid, and maintain a single leg stance while reaching with the opposite leg to touch as far as possible along a chosen excursion. They were then instructed to touch the farthest point possible, as light as possible, along a chosen excursion with the most distal part of their reach foot. Cases were then instructed to return to a bilateral stance while maintaining their balance. Three trials were taken for the testing and the average of the three trials was considered as dynamic balance scores. The average scores for each excursion (anterior excursion, anteromedial excursion, medial excursion, posteromedial excursion, posterior excursion, posterolateral excursion, lateral excursion, and anterolateral excursion) were recorded as the case's dynamic balance scores.
The training was carried for 5 sessions a week for 4 weeks. This study was conducted with one to one, investigator to subject supervision.
Functional balance training protocol
Functional balance training program included the following components performed five times per week with a day's break at the end of 3rd day.
This stretching required subject to place the foot on a 30° step board and stretch the Achilles with knee straight for 3 sets × 20 s, and then stretch with knee bent for 3 sets × 20 s. Subjects did not wear sandals or shoes during achilles stretching.
Short foot concept contractions
In this maneuver, short-foot position was achieved three times, and each contraction held for 60 s. During these contractions, casess were instructed to pull the arch of the foot up by shortening the length and narrowing the width of the foot without flexing the toes.
High knee walking
Cases were instructed to flex the limb to approximately 70° of hip flexion and 90° of knee flexion while simultaneously standing on the contra lateral limb . After flexing, cases returned the limb to a straightened position by taking a step out in front of the body. Cases then took step forward with stance limb so that the limbs were shoulder width apart and parallel to each other.
Lateral side step
Lateral side steps had the subjects to step laterally while staying in a defensive stance. Subjects then lifted the foot slightly off the ground and quickly moved the limb laterally. Contralateral limb then move medially to bring the limbs shoulder width apart.
Walking exercises (forward and backward)
This required the subjects to step forward while maintaining a defensive stance position. Here, subjects did not flex their hips and knees to 70° and 90°, respectively. After stepping, subject takes step forward with the contralateral limb so that the limbs are shoulder width apart and parallel. Same procedure needs to be repeated for backward walk.
This required subjects to perform a lateral side step while maintaining a defensive stance. The subjects then flexes the limb that moved laterally to 70° of knee flexion and straightens the contralateral limb. The knee of the limb that moves laterally will then be extended back to the original defensive stance knee position as the contralateral limb moved medially.
The squat exercise again required subject to perform a lateral side step and to maintain a defensive stance. After stepping laterally, the contralateral limb will move laterally so that limbs will then move medially, so that limbs are approximately shoulder width apart and parallel. Subjects will then perform a squat by flexing their knees to 70° of knee flexion. Knees were then extended back to the original defensive stance knee positions.
Wobble Board training protocol
Single leg Stance on Wobble board with eyes open and closed
Cases maintained a single leg stance with the contralateral knee flexed to 75° and arms folded across their chest with their eyes open and closed. Exercises involved maintaining a single leg stance on a fixed surface with eyes open and closed.
Double leg stance on wobble board with eyes open and closed
Cases were asked to stand on both legs on circular wobble board both with eyes open and closed and were instructed to maintain balance on the wobble board for the maximum period.
Double leg stance and performing a squat with eyes open and closed
Cases were instructed to perform half squat in double stance with eyes open and closed.
Cases were asked to carry on their normal activities and refrain from any balance training except that was required by the study.
The data were analyzed using statistical tests, which were performed using SPSS version 11.5 software (Chicago) used for statistical analysis. The dependent variables were analyzed using 2 × 3 mixed analysis of variance. There was one between factor-type of training with two levels (functional balance training vs. wobble board training), and one within factor - time with three levels (pretraining, at the end of 2 weeks and posttraining at 4 weeks).
A 0.05 level of significance was used for all comparisons.
| Results|| |
Single leg stance test (eyes closed)
The analysis revealed that both types of training influenced single leg stance test in eyes closed and open conditions. In the single leg stance test with eyes closed, there was a significant effect for the within-group comparison, P < 0.05 for both groups. However, there was a nonsignificant difference for the between-group comparison (P > 0.05) [Figure 1].
|Figure 1: Comparison of means (± standard deviation) of single leg stance test score (eyes closed)|
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Post hoc analysis revealed that both types of training improved the single leg stance test scores under eyes closed condition. There was a significant difference with P < 0.05 among both training groups at the end of 4 weeks of balance training.
Single leg stance (eyes open)
The analysis revealed that there was a nonsignificant difference found in functional training group, i.e. P > 0.05 but a statistically significant difference in wobble training group P < 0.05 for the within-group comparison. However, there was a nonsignificant difference found for between-group comparison with P > 0.05 [Figure 2].
|Figure 2: Comparison of means (± standard deviation) of single leg stance test score (eyes open)|
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Post hoc analysis revealed that there was a significant difference between the groups from 2nd to 4th week, but nonsignificant difference was found in functional training group (P > 0.05) However, significant differences were found for wobble board group with P < 0.05.
Star Excursion Balance Test
The results showed that there was a nonsignificant difference for between-group comparison (P > 0.05) at the end of 4 weeks of balance training. There was a statistically significant difference found in both the training groups.
Post hoc analysis revealed a significant difference from pre- to post-training period, i.e., 0-4 week in functional training group (P < 0.05) and nonsignificant difference for wobble board group (P > 0.05) [Figure 3].
|Figure 3: Comparison of means (± standard deviation) of Star Excursion Balance Test score in anterior direction|
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There was a nonsignificant difference was observed for between-group comparison, i.e. P > 0.05. There was a significant difference in functional training group for the within-group comparison (F = 6.51, P = 0.005) and nonsignificant difference for wobble board training group (F = 2.58, P = 0.093).
Post hoc analysis revealed nonsignificant difference for functional group and significant difference from 0 to 2 weeks of balance training. Interestingly, functional displayed nonsignificant difference from 2 to 4 weeks and wobble board group showed significant difference from 2 to 4 weeks of balance training [Figure 4].
|Figure 4: Comparison of means (± standard deviation) of Star Excursion Balance Test score in anteromedial direction|
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There was a nonsignificant difference observed for between-group comparisons from 0 to 4 weeks of balance training. There was a significant difference for within-group comparison (P < 0.05) in functional training group and nonsignificant difference for wobble board training group (P > 0.05) [Figure 5].
|Figure 5: Comparison of means (± standard deviation) of Star Excursion Balance Test score in anterolateral direction|
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Post hoc analysis revealed that there was a significant difference observed in functional group from 0 to 4 weeks of training. However, wobble board group showed that nonsignificant differences were observed throughout the study period (P > 0.05).
The results showed that there was a nonsignificant difference for between-group comparison, i.e., P > 0.05 from 0 to 4 weeks of balance training. There was a significant difference observed in functional group for within-group comparison (P < 0.05) and nonsignificant difference in wobble board group (P > 0.05).
Post hoc analysis revealed a significant difference in functional group (P < 0.05) and nonsignificant difference in wobble board group (P > 0.05) [Figure 6].
|Figure 6: Comparison of means (± standard deviation) of Star Excursion Balance Test score in medial direction|
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The results displayed significant differences were observed for between-group comparison from 0 to 4 weeks of training (P < 0.05). There was a significant difference for within-group comparison in functional group (P < 0.05) and nonsignificant difference for wobble board group (P > 0.05).
Post hoc analysis showed significant differences for functional group (P < 0.05) and nonsignificant difference for wobble board group from 0 to 2 weeks of balance training. However, significant differences were observed for functional training group (P < 0.05) and nonsignificant differences for wobble board group from 0 to 4 weeks of training (P > 0.05) [Figure 7].
|Figure 7: Comparison of means (± standard deviation) of Star Excursion Balance Test score in lateral direction|
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The analysis revealed nonsignificant difference for between-group comparison from 0 to 4 weeks of training (P > 0.05). There was a statistically significant difference for within-group comparison in functional training group (P < 0.05) and nonsignificant difference for group wobble board (P > 0.05).
Post hoc analysis revealed a nonsignificant relationship for both groups from 0 to 2 weeks of training (P > 0.05). However, functional group showed significant difference from 0 to 4 weeks of training (P < 0.05) [Figure 8].
|Figure 8: Comparison of means (± standard deviation) of Star Excursion Balance Test score in posterior direction|
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The results showed that significant differences were observed for between-group comparison from 0 to 4 weeks of balance training (P < 0.05). There was a nonsignificant difference in functional group for within-group comparison (P > 0.05) and significant difference in wobble board group (P < 0.05).
Post hoc analysis revealed nonsignificant differences for the whole of the training period from 0 to 4 weeks (P > 0.05) [Figure 9].
|Figure 9: Comparison of means (± standard deviation) of Star Excursion Balance Test score in posteromedial direction|
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The results suggested that nonsignificant differences were observed for between-group comparison (P > 0.05). There was nonsignificant difference in functional group for within-group comparison (P > 0.05) and significant difference in wobble board group (P < 0.05).
Post hoc analysis revealed nonsignificant difference for both the groups from 0 to 2 weeks of training (P > 0.05). However, wobble board group showed significant differences at the end of training after 4 weeks (P < 0.05) [Figure 10].
|Figure 10: Comparison of means (± standard deviation) of Star Excursion Balance Test score in postero lateral direction|
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| Discussion|| |
The results of our study suggested that functional balance training and wobble board training group produced similar results on balance scores after 4 weeks of balance training on subjects with functional ankle instability.
The main findings of our study are in accordance with work done by Michell, who suggested that functional balance training may not be an effective means of improving postural stability in subjects with functionally unstable ankles. Previous study by Ross et al. had suggested that functional balance training using exercise sandals might not have proved to be an effective tool for improving postural stability but may serve as an alternative therapy for inculcating balance retraining program as a preventive tool for those indulging in sports involving jumping and cutting maneuvers such as football and volleyball.
The use of coordination and balance training has proved its efficacy in preventing the recurrent episodes of ankle sprains. Tropp (Sports Medicine, 2003) examined the effects of an ankle disk training program in 65 male soccer players with previous ankle sprain and found an 80% decrease in the frequency of repeat sprain over a 6-month period compared with controls with a similar history of ankle injury. In lieu of the results presented by Ross and Michell et al., our study results too did not consider the effects of functional balance training in reducing the future recurrent sprains but may have an implication toward balance training as an injury prevention strategy in sports.
The results of our study suggest that subjects from functional balance training group performed better than wobble board training group from 2nd to 4th week of training but failed to achieve statistically significant results at the end of 4 weeks. Effect of fatigue and chronic ankle instability on dynamic postural control has been studied earlier by Gribble and Hertel. The result of their study suggested that chronic ankle instability and fatigue created postural control deficits that appeared to be linked to kinematic changes at the hip and knee. This factor may have been responsible for inconsistent findings at the end of 4 weeks in our study as well as both the training protocols primarily focused on proprioception training and placed lesser emphasis on other extraneous factors such as muscle fatigue mainly due to lack of time and availability. Our study had a training period of only 4 weeks; cases were asked to complete 5 sessions/week, but this duration of training stimulus may not have been sufficient to result in neuromuscular adaptation to influence changes in static and dynamic control.
The results of our study also suggest that both Wobble Board Training (WBT) and Functional Board Training (FBT) led to an increase of balance scores in the first half of the study but this rate of increase could not be improved for the entire 4 weeks of training. However, gains in FBT group were found to be steadier throughout the study. In view of the data presented, it would seem reasonable to suggest that initial gains in balance scores may be due to the novelty of the training programs which motivated the cases to perform better over a period.
Well-suited adaptability and marginally better improvements on both static and dynamic postural control in FBT group may be attributed to the fact that "short foot concept" used helped in an efficient activity and larger muscle recruitments. A study by Ruthermol suggested that "short foot concept" which includes intrinsic foot flexors to contract in the absence of toe flexion, did not improve postural stability in healthy subjects but helped in developing new muscle activation patterns. His explanation toward subjects not improving postural control was that short foot maneuver caused his subjects to focus more toward muscle activation than on being motionless during single leg stance testing. We had our subjects perform functional balance exercise while using "short foot concept" for nearly 20 sessions over a period of 4 weeks. However, the design of our study did not allow us to study the effectiveness of short foot concept technique.
Subjects from WBT group showed statistically significant improvements mainly in one direction of SEBT test, i.e., posterolateral direction. This may be due to the fact that differing movement patters of FBT provided more challenge to the athletes from different sporting backgrounds. One more reason for unidirectional improvement in WBT group might be that this is the easiest of the directions to perform amongst the 8 test directions of SEBT test.
Another potential reason for nonsignificant changes in dynamic postural control may be the time of testing the dependent variables. Most of the pre- and post-testing of dependent variables were taken during afternoon. Diurnal variations in the measures of dynamic postural control have been proven recently by Gribble and Tucker et al. The result of their study suggested that performance of dynamic postural control like SEBT may be better in the morning than afternoon or evening.
Posteromedial direction has been reported to be highly predictor of performance of 8 components of tests on limbs with Functional Ankle Instability. Our study has also shown consistently significant improvements among both groups.
This study also demonstrates that subjects with a history of unilateral inversion ankle sprains are less stable in single-limb stance when subjects closed their eyes. There was no difference between the injured and noninjured leg when their eyes were open. This demonstrates that subjects having ankle sprains might use their eyes to compensate for the loss in proprioceptive sense due to ankle sprains. According to the theory proposed by Freeman in 1965, subjects with ankle sprain might damage their mechanoreceptors over the ankle joint. The damage in the mechanoreceptors might cause an impair in proprioceptive sense, which is important to control the instantaneous and quantitatively precise contractions of ankle muscles and remain stable on ground. It is well known that compensatory mechanisms are put into action in case of insufficiency in one system. Hence, the substituting action of the other noninvolved sensory sources (visual and vestibular systems) makes it possible that disturbed proprioceptive system resulting with a normal postural sway. Unfortunately, during sporting activities, the sensory input from the visual system might be reduced. This happens when athletes use their eyes to follow the ball, their teammates or opponents.
In view of our study, on single leg stance, under conditions of eyes open and closed, significant improvements were seen in both groups from 0 to 2 weeks but failed to achieve significance after the end of training. Quiet standing in single leg stance might be a task which may get tougher when progressing from eyes open to eyes closed condition. Thus, there may have been a tendency to use alternate motor synergies such as hip strategy to adequately accomplish the task in presence of pathology.
One important observation of our study was that in general, there was a significant improvement seen consistently over 4 weeks of balance training in FBT group than WBT group. This may suggest a viewpoint that FBT protocol is more easily identifiable and is more focused on sports specific activities than single static positions of wobble board training.
Finally, our study emphasized upon the fact that balance training, irrespective of the protocol adopted, is an integral yet underestimated component of rehabilitation following instability of ankle largely because of various still unrecognized facets of chronic ankle instability.
| Conclusion|| |
The results of our study indicate that irrespective of the training method used, subjects with functional ankle instability displayed better clinical improvements in static and dynamic balance though statistically nonsignificant. However, functional balance training protocol was found to be more suitable and showed better compliance in comparison to wobble board training method.
Undoubtedly, the wobble board training has already proved to be an effective means of proprioceptive training, but there is a need for a more cost-effective method of balance training in subjects with functional ankle instability due to its ever-widening horizon.
Clinically, functional balance training may prove to be an effective means of proprioceptive rehabilitation thus may prove to be tool to bring down the epidemiology of ankle sprains in sports.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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