***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: STUDY DESIGN R and omized controlled trial with pretraining , posttraining , and follow-up repeated measures . OBJECTIVE To determine the effectiveness of a 4-week elastic resistance exercise program on  balance  in subjects with and without a history of sprained ankles . BACKGROUND Several research ers have suggested that improving balance may help alleviate the symptoms of functional ankle instability and reduce the rate of recurrent ankle sprains . METHODS AND MEASURES Forty subjects ( 20 males , 20 females ; 20 subjects with chronic ankle instability [ CAI ] , 20 healthy ) participated in the study . Ten subjects ( 5 males , 5 females ) from each CAI and healthy group were r and omly assigned to either the exercise or control group , result ing in a total of 4 groups . Total travel distance of the center of pressure , monitored using a force platform , was measured before training , after 4 weeks of training , and at a 4-week follow-up . RESULTS There were no interactions between gender , ankle sprain history , or training groups . Balance significantly improved in subjects with and without a history of ankle sprains following 4 weeks of elastic resistance exercises . Mean improvement in balance for the exercise group following training , reflected through a decrease in total travel distance , was -11.1 cm ( 95 % confidence interval : -14.0 to -8.2 cm ) . These improvements in balance were retained 4 weeks after training . CONCLUSIONS Balance was improved after 4 weeks of elastic resistance exercise in subjects with and without a history of lateral ankle sprains . Balance improvements persisted 4 weeks following the treatment cessation A bi-directional bicycle pedal that combines proprioceptive training and evertor strengthening has been developed for the treatment of residual instability after ankle sprains . A prospect i ve r and omized study was carried out on 19 subjects with recurrent ankle sprains and positive stress X-ray films . The subjects were r and omized to use either a bi-directional test pedal or a traditional uni-directional bicycle pedal and then completed a 6-week high-intensity training program on a cycle ergometer . Assessment of training intensity level was based on maximum oxygen uptake values , heart rate and lactate concentration in blood at various submaximal workloads . After completion of the training program , the subjects who had used the test pedal increased peak eversion torque at 180 degrees degrees s-1 by 14.2 % ( P = 0.020 ) , reduced figure-of-eight running time by 0.24 s ( P = 0.003 ) , improved single leg stance speed from 72.5 % to the maximum speed of 80 % ( P = 0.005 ) , and improved Karlsson functional score by 5.1 points ( P = 0.005 ) . In the control group , single leg stance improved from 56.1 to 67.8 % ( P = 0.018 ) , but otherwise no significant effects were found . This study indicates that short-term high-intensity training with a bi-directional pedal improves ankle performance and may be an option in the treatment of recurrent ankle sprains Early range of motion training after ligament reconstruction of the ankle ligaments for chronic ankle joint instability was evaluated . Forty patients were operated on with anatomic reconstruction of the lateral ankle ligaments , i.e. shortening , imbrication and reinsertion . The patients were r and omized postoperatively between two groups : ( 1 ) immobilization for 6 weeks in a plaster cast and ( 2 ) early range of motion training , in a Walker-Boot . Both groups underwent an identical rehabilitation program . with peroneal strengthening and co-ordination training after 6 weeks . The functional results were evaluated using a scoring scale and the mechanical stability with st and ardized stress radiographs . The minimum follow-up was 2 years . The functional results were satisfactory in 16 ( 80 % ) of the patients in group I , and 19 ( 95 % ) in group II . The mean values of anterior talar translation and talar tilt were not significantly different between the groups preoperatively nor at follow-up . The mean time period for sick leave was significantly shorter for group II , 6.5±1.6 weeks compared with 8.5±1.8 weeks for group I. The mean time period for return to sports activity was significantly shorter for group II , 9.5±2.2 weeks , compared with 12.5±2.6 weeks for group I. Early range of motion training is recommended after ligament reconstruction of the ankle , as it will enable earlier return to sports activities , shorter sick leave and preserved mechanical stability Objectives : To examine the effect of six weeks of strength and proprioception training on eversion to inversion isokinetic strength ratios ( E/I ratios ) in subjects with unilateral functional ankle instability . Methods : Thirty eight subjects were r and omly assigned to one of four treatment groups : strength training ( S ) ; proprioception training ( P ) ; strength + proprioception training ( B ) ; control ( C ) . Isokinetic strength was tested before and after training using a Kin Com 125 automatic positioning isokinetic dynamometer . Subtalar joint eversion and inversion motions  were tested both concentrically and eccentrically through a range of motion involving 40 ° . All peak torque and average torque values were normalised for body mass . E/I ratios were calculated from average torque and peak torque measures by taking the concentric eversion value and combining it with the eccentric inversion value . Data were analysed using a mixed model analysis of variance with repeated measures on the test factor . Average torque and peak torque E/I ratios at 30 and 120 ° /s were analysed separately . Results : There were no significant differences in average torque and peak torque E/I ratios of the functionally unstable ankle for any of the groups after training compared with before . Conclusions : Six weeks of strength and proprioception training ( either alone or combined ) had no effect on isokinetic measures of strength in subjects with self reported unilateral functional instability . Further studies examining this agonist ( concentric ) to antagonist ( eccentric ) muscle group strength ratio are needed Exercises to improve joint proprioception and coordination of the functionally unstable ankle are advocated throughout the literature , yet there is little evidence that these exercise have any effect on proprioception and balance . The purpose of this study was to determine the effects of a 6-week coordination and balance training program on proprioception of subjects with functional ankle instability . Forty-five subjects ( age = 22.53 + /- 3.95 years , height = 172.04 + /- 10.0 cm , weight = 71.72 + /- 15.7 kg ) were r and omly placed into a control ( Group 1 ) , sham ( Group 2 ) , or experimental ( Group 3 ) group . The experimental group trained 3 days per week , 10 minutes each day , performing various balance and proprioception exercises .  Postural sway and active and passive joint position sense were assessed . Analysis of variance for postural sway modified equilibrium score for anterior and posterior sway , as well as medial and lateral sway revealed significant four-way interactions . Tukey post hoc analyses revealed that Group 3 performed significantly better ( p < .05 ) than Group 1 and Group 2 on the posttests . There were no significant differences for joint position sense or postural sway index . Results suggest that balance and coordination training can improve some measures of postural sway . It is still unclear if joint position sense can be improved in the functionally unstable ankle STUDY DESIGN Prospect i ve , r and omized controlled trial . OBJECTIVE To examine the effects of a 4-week rehabilitation program for chronic ankle instability ( CAI ) on postural control and lower extremity function . BACKGROUND CAI is associated with residual symptoms , performance deficits , and reinjury . Managing CAI is challenging and more evidence is needed to guide effective treatment . METHODS AND MEASURES Subjects with unilateral CAI were r and omly assigned to the rehabilitation ( CAI-rehab , n=16 ) or control ( CAI-control , n=13 ) group . Subjects without CAI were assigned to a healthy group ( n=19 ) . Baseline testing included the ( 1 ) center of pressure velocity ( COPV ) , ( 2 ) star excursion balance test ( SEBT ) , and ( 3 ) Foot and Ankle Disability index ( FADI ) and FADI-Sports Subscale ( FADI-Sport ) . The CAI-rehab group completed 4 weeks of rehabilitation that addressed range of motion , strength , neuromuscular control , and functional tasks . After 4 weeks , all subjects were retested . Nonparametric analyses for group differences and between-group comparisons were performed . RESULTS Subjects with CAI demonstrated deficits in postural control and SEBT reach tasks of the involved limb compared to the uninvolved limb and reported functional deficits of the involved limb compared to healthy subjects . Following rehabilitation , the CAI-rehab group had greater SEBT reach improvements on the involved limb than the other groups and greater improvements in FADi and FADI-Sport scores . CONCLUSIONS These results demonstrate postural control and functional limitations exist in individuals with CAl . In addition , rehabilitation appears to improve these functional limitations . Finally , there is evidence to suggest the SEBT may be a good functional measure to monitor change after rehabilitation for CAI The present study investigated the effects of two different surgical procedures for the treatment of chronic ankle instability . Ten patients treated with an  anatomic reconstruction using a periosteal flap were compared with a second group that received an Evans tenodesis . All patients were evaluated before and after surgery with clinical and radiographic examinations as well as  dynamic pedobarography . Patient satisfaction and radiographic and functional results were comparable in both groups and revealed a good restoration of joint stability and gait symmetry . Our results indicate that both methods of ankle ligament reconstruction achieve a comparable clinical and functional outcome within 1 year after surgery Background Ankle sprains are frequent injuries in soccer . Several strategies can be used to prevent further ankle sprains in athletes : the most common are proprioceptive training , strength training , and orthoses . Objective To investigate which of these 3 interventions is the most effective in preventing ankle sprains in athletes with previous ankle inversion sprain . Study Design R and omized controlled trial ; Level of evidence , 1 . Methods and Measures Eighty male soccer players ( age , 24.6 ± 2.63 years ; height , 175.60 ± 4.36 cm ; weight , 64.26 ± 8.37 kg ) in the first division of a men 's league who had experienced previous ankle inversion sprain were r and omly selected from an original population of 120 players . The subjects were individually and r and omly assigned to 4 study groups : group 1 ( n = 20 ) followed the proprioceptive program , group 2 ( n = 20 ) followed the strength program , group 3 ( n = 20 ) used orthoses , and group 4 ( n = 20 ) was the control group . Data on the frequency of ankle sprain reinjury were collected at the end of the session . Results There were no significant differences among the groups in the number of exposures . The incidence of ankle sprains in players in the proprioception training group was significantly lower than in the control group ( relative risk of injury , 0.13 ; 95 % confidence interval , 0.003 - 0.93 ; P = .02 ) . The findings with respect to the strength and orthotic groups in comparison with the control group were not significant ( relative risk of injury , 0.5 ; 95 % confidence interval , 0.11 - 1.87 ; P = .27 for strength ; relative risk of injury , 0.25 ; 95 % confidence interval , 0.03 - 1.25 ; P = .06 for orthotic group ) . Conclusion Proprioceptive training , compared with no intervention , was an effective strategy to reduce the rate of ankle sprains among male soccer players who suffered ankle sprain The purpose of this study was to examine the effects of a single joint mobilization treatment on dorsiflexion range of motion ( DF ROM ) , posterior talar glide , and dynamic and static postural control in individuals with self-reported chronic ankle instability ( CAI ) . In this r and omized cross-over study , subjects received a  Maitl and Grade III anterior-to-posterior joint mobilization treatment and a control treatment of rest for 5 min . Weight-bearing DF ROM , instrumented posterior talar displacement and posterior stiffness , the anterior , posteromedial , and posterolateral reach directions of the Star Excursion Balance Test ( SEBT ) , and time-to-boundary ( TTB ) single-limb stance static postural control  were assessed on both treatment days in 9 males and 11 females with CAI . The results indicated that the joint mobilization treatment was associated with significantly greater DF ROM ( p = 0.01 ) and TTB in the anterior-posterior direction with eyes-open ( p < 0.05 ) . Although not significant , trends were identified in posterior talar displacement ( p = 0.08 ) and the mean of TTB in the medial-lateral ( ML ) direction ( p = 0.07 ) . No significant differences were observed in the st and ard deviation of TTB in the ML direction , the SEBT , or posterior stiffness ( p > 0.05 ) . This indicates that a single joint mobilization treatment has mechanical and functional benefits for addressing impairments in sensorimotor function and arthrokinematic restrictions commonly experienced by individuals with CAI OBJECTIVE The purpose of this study was to determine the efficacy of adjusting the ankle in the treatment of subacute and chronic grade I and grade II ankle inversion sprains . DESIGN A single-blind , comparative , controlled pilot study . SETTING Technikon Natal Chiropractic Day Clinic . PARTICIPANTS Thirty patients with subacute and chronic grade I and grade II ankle inversion sprains . Pat 
    Output:
    
Limited evidence was found for the effectiveness of an early mobilization program after surgery .
In chronic ankle complaints after an ankle sprain , a training program gives better results for pain and function , and a decrease of recurrent ankle sprains , than a wait- and -see policy .
There was insufficient evidence to determine the most effective surgical treatment , but limited evidence suggests that postoperative , early mobilization was more effective than a plaster cast .