<LEAP> highlights the findings and application of Cochrane reviews and other evidence pertinent to the practice of physical therapy. The Cochrane Library is a respected source of reliable evidence related to health care. Cochrane systematic reviews explore the evidence for and against the effectiveness and appropriateness of interventions—medications, surgery, education, nutrition, exercise—and the evidence for and against the use of diagnostic tests for specific conditions. Cochrane reviews are designed to facilitate the decisions of clinicians, patients, and others in health care by providing a careful review and interpretation of research studies published in the scientific literature.1 Each article in this PTJ series summarizes a Cochrane review or other scientific evidence on a single topic and presents clinical scenarios based on real patients or programs to illustrate how the results of the review can be used to directly inform clinical decisions. This article focuses on a patient with chronic ankle instability who has re-sprained his ankle and is now unable to participate in sports. Could a neuromuscular training program improve his functional outcomes?
Ankle sprain, in particular injury to the lateral ligament complex of the ankle joint, is one of the most frequently encountered lower-limb injuries in sporting populations.2 In the acute phase, ankle sprains are associated with pain, swelling, ecchymosis, and loss of function, with up to one quarter of all injured people being unable to attend work for more than 7 days postsprain.3 In addition to restricted joint range of motion and increased joint laxity, common clinical and research findings are disruption in neuromuscular control as manifested by decreased postural stability, altered muscle activation patterns, and aberrant joint physiological and accessory movement.
In the weeks following an ankle sprain, activities of daily living can be compromised, and, even though acute symptoms resolve, persistent symptoms are reported to occur in 30% to 40% of people,4 with higher incidences being reported in athletes involved in high-velocity, dynamic sports.5 These symptoms, which include a feeling of joint instability and repeated episodes of the ankle joint giving way, are part of the clinically described entity chronic ankle instability.6 “Chronic ankle instability” is an encompassing term used to describe the presence of mechanical instability and functional instability following ankle sprain.6 The symptoms still persist in up to 25% of people at 3 years after the initial sprain.7
There are few evidence-based clinical guidelines for ankle sprain management in primary care. Clinical practice varies widely and often can be limited to basic advice followed by immediate discharge in the absence of ankle joint fracture.8 Recently, Hertel9 developed a widely accepted paradigm of chronic ankle instability, whereby various functional insufficiencies and mechanical insufficiencies are described. Clinicians can use strategies to treat the various functional insufficiencies described in the paradigm of Hertel.9 The generic term “neuromuscular training” is used to describe a combination of functionally based exercises, including postural stability, proprioceptive, and strength training, as part of a rehabilitation regimen.
A recent Cochrane review investigated the effectiveness of any conservative or surgical treatments for chronic ankle instability in adults.10 Of the 10 included studies, 4 evaluated neuromuscular training. The remaining studies examined surgical interventions (4 studies) or mobilization versus immobilization after surgery (2 studies). Only the results concerning neuromuscular training are presented here (Appendix).
Studies compared 4 weeks of supervised neuromuscular training (including wobble board and other balance exercises) with no training (3 studies) and bidirectional to unidirectional pedaling on a recumbent stationary bicycle (1 study). The study sample sizes were small, and most studies had methodological flaws (eg, no concealed allocation). The studies did not provide follow-up data other than data collected at the end of the treatment period. The pooled results from 2 studies showed statistically significant but small functional gains when neuromuscular training was compared with no training. A third study comparing neuromuscular training with no training also showed similar results. There was no difference between bidirectional or unidirectional pedaling. The Cochrane review did not report adverse events as an outcome, but reviewing the included studies showed that 1 of the 4 studies reported on adverse events. Hale et al11 compared a 4-week neuromuscular training program with no training and reported that no participant withdrew from the study due to adverse events.
Take-Home Message
Because of the low number of studies, the small sample sizes, and the risk of bias, there is only limited evidence regarding the efficacy of neuromuscular training for ankle instability. However, the results showed a small, short-term treatment benefit supporting supervised neuromuscular training conducted over 20 to 30 minutes a few times a week for 4 weeks.
<LEAP> Case #9 Neuromuscular Training for Chronic Ankle Instability
Can neuromuscular training help this patient?
Mr. R is a 28-year-old amateur soccer player who works as an accountant. He had an acute right ankle sprain, sustained while running during training, on a background of chronic ankle instability. He played with a club in his local competitive league and had 2 pitch training sessions and 1 game every week during the season, which lasted approximately 32 weeks. He has had recurrent episodes of ankle instability over the past 4 years, with 2 to 3 re-sprains per year. All of the episodes have occurred while participating in or training for his sport.
Mr. R reported his current symptoms over the lateral aspect of his right ankle, with 5/10 pain on the visual analog scale. His ankle was stiffer getting out of bed in the morning, and it took a few minutes before he could walk freely. His pain was aggravated by running or any sudden twisting or turning, and he was currently unable to participate in training or competition. There was moderate effusion of the ankle joint and bruising along the lateral aspect of the dorsum of the foot, with marked laxity on the anterior drawer test and pain and moderate laxity on the talar tilt test. There was tenderness along the lateral ankle, particularly over the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL). He had mild weakness through his peroneal and gastrocnemius muscles, reduced passive dorsiflexion of the talocrural joint, and hypomobililty on an anteroposterior glide of the talus. His knee to the wall score was 11 cm on the left side and 6 cm on the right side, with reported stiffness and lateral ankle pain.12 His timed single-leg stance postural stability test with eyes closed was reduced on the right side (4 seconds; left side, 16 seconds). He scored 58 on the Foot and Ankle Score Scale component of the Foot and Ankle Outcomes Questionnaire. The Foot and Ankle Score Scale is a 20-item questionnaire on stiffness, swelling, pain, activity limitation, balance, and giving way, where 0 represents a poor outcome and 100 represents the best possible outcome.13 The scale has good content and construct validity and reliability for a variety of ankle and foot conditions.14 Mr. R's score placed him well below the 25th percentile of the normative data, suggesting marked disability.15 Magnetic resonance imaging of Mr. R's right ankle showed complete rupture of his ATFL and a grade 2 tear of his CFL. There was no evidence of any fracture, but there was mild periosteal bruising of the talus.
How did the physical therapist apply the results of the Cochrane Systematic Review to the patient?
Mr. R reported having an acute ankle sprain with a background of chronic ankle instability affecting his sporting and daily activities. The clinical question, using the PICO (Patient, Intervention, Comparison, Outcome) format, is: Would Mr. R benefit from a neuromuscular training program to improve his functional outcomes? The Cochrane review supports the use of neuromuscular training to improve function in chronic ankle instability. The review reported on studies that recruited participants who had characteristics similar to those of Mr. R; thus, the results could be generalized to him. Mr. R was otherwise healthy and did not have comorbidities that would prohibit his participation in a supervised exercise program.
Based on Mr. R's presentation and the evidence from the systematic review, the physical therapist recommended a neuromuscular training program to the patient. Mr. R had reported carrying out some neuromuscular training after his previous ankle sprains. His adherence to prescribed programs was poor, but he was willing to start a new neuromuscular training program. Mr. R received treatment once a week for the first 4 weeks and then had his final review appointment on week 6. His treatment consisted initially of reduction of pain and swelling through ice, compression, and nonsteroidal anti-inflammatory drugs, as well as passive accessory and passive physiological joint mobilizations to restore full talocrural mobility. He was given a home neuromuscular training program to improve his balance, ankle mobility, and ankle strength (Tab.). He was expected to carry out this program 5 days a week. As there was ongoing structural laxity, Mr. R had his ankle taped during all training sessions and matches as he returned to soccer to provide additional structural support while continuing to improve his postural stability and strength.
Mr. R's Neuromuscular Training Program as Prescribed by His Physical Therapista
How well do the outcomes of the intervention provided to the patient match those suggested by the systematic review?
After 6 weeks, Mr. R had returned to full training. He had full talocrural mobility and full strength in his peroneal and calf muscles. There was ongoing but pain-free laxity on anterior drawer and talar tilt testing. His single-leg stance postural stability test with eyes closed improved to 10 seconds on his affected side. He scored 97 on the Foot and Ankle Score Scale, indicating he had almost returned to full function (normative mean=93.15, SD=12.33).15 Mr. R understood the importance on continuing to improve his static postural stability and the need to achieve symmetry and maintain these improvements during the season to avoid further re-sprain.
Can you apply the results of the systematic review to your patients?
The findings of the Cochrane review provide some evidence that neuromuscular training can lead to small, short-term improvements in function compared with no training. For Mr. R, the training effect allowed him to improve function and return to sporting activities. Although the studies in the Cochrane review recruited patients with an average age in the 20s, as in Mr. R's case, there is no reason why the same benefits would not be expected in the general adult or adolescent population seen by physical therapists for chronic ankle instability. Studies in the Cochrane review do not provide evidence on the long-term benefits of neuromuscular training, and, to our knowledge, no relevant randomized controlled trials have been published since the last search date of this Cochrane review (February 2010). However, evidence from exercise trials in other musculoskeletal conditions suggests that benefits of a training program decline over time and booster sessions are useful to maintain long-term benefits.16
There are measures related to the functional and mechanical insufficiencies that are thought to contribute to chronic ankle instability, such as deficits in strength, proprioception, and neuromuscular or postural control9 (for a clinical case using some of these measures, see the case report by O'Driscoll et al17). These measures were not included as outcomes in the Cochrane review; however, other evidence is available to supplement the review's findings. A recent systematic review with best evidence synthesis concurs with the findings of the Cochrane review and concludes that neuromuscular training can improve discrete functional insufficiencies (eg, static and dynamic postural stability) associated with chronic ankle instability.18 The results indicate that in the future significant emphasis should be placed on the mode specificity of neuromuscular training. This would seem a pertinent point given the multifactorial nature of chronic ankle instability. Another recent systematic review shows that neuromuscular training can reduce lower-limb injuries in an athletic population.19 Furthermore, a neuromuscular training program could be implemented in people after acute ankle sprain without the diagnosis of chronic ankle instability. Hupperets and colleagues20,21 showed that after an ankle sprain, a home proprioceptive exercise program is effective and cost-effective at preventing re-sprain at 1 year.
What can be advised based on the results of this systematic review?
The results of the Cochrane review provide stronger evidence than individual studies that neuromuscular training can improve short-term functional outcomes in people with chronic ankle instability. The programs used in the reviewed studies are 20 to 30 minutes in duration a few times a week for 4 to 6 weeks and mostly consist of progressive postural stability, proprioceptive, and strengthening exercises. The long-term benefits of neuromuscular training in chronic ankle instability are not known, but studies have shown that neuromuscular training can reduce the risk of other lower-limb injuries, including ankle re-sprain.19,21
The Cochrane review also provides insights for future research in neuromuscular training for ankle instability. What is required is large, adequately powered trials with a broad age group and information on cost-effectiveness. There also is a need to establish treatment effects beyond the immediate treatment period and identify the specific training components that constitute the most effective form of neuromuscular training.
Appendix.
Neuromuscular Training for Chronic Ankle Instability: Cochrane Review Results10
Footnotes
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Dr Lin is funded by the National Health and Medical Research Council, Australia.
- Received October 13, 2011.
- Accepted April 11, 2012.
- © 2012 American Physical Therapy Association
References
