Balance Training for Persons With Functionally Unstable Ankles.

Balance Training for Persons With Functionally Unstable Ankles Rozzi SL, Lephart SM, Sterner R, Kuligowski L (College of Charleston, Charleston, SC; University of Pittsburgh, Pittsburgh, Pa), J Orthop Sports Phys Ther. 1999;29:478-486.

The researchers in the study compared the effects of a 4-week balance training program on the ability to perform a single-leg stance in 2 groups of subjects. The nonrandomized 2-group pretest-posttest design compared static balance assessments in 13 subjects who reported functionally unstable ankles (5 women, 8 men; mean age=21.9 [+ or -] 3.1 years) with those of 13 subjects who did not have impairments (6 women, 7 men; mean age=21.2 [+ or -] 2.5 years).

Subjects performed a single-leg static balance test of both lower extremities on a Biodex Stability System at 2 stability levels: 6 (more stable) and 2 (less stable). Each test was rated with a stability index (SI) score that quantified the subjects' ability to control the platform's angle of tilt during a 20-second test. A higher SI indicated greater platform motion and less stability. A mean SI was calculated for the 3 tests at each of the 4 test conditions: each of 2 limbs at 2 stability levels. All subjects also completed an unvalidated ankle joint functional assessment tool questionnaire.

After the pretest assessments all subjects participated in a unilateral, multi-level, static and dynamic balance training program on the Biodex Stability System 3 times a week for 4 weeks. The subjects with unstable ankles trained the involved limb, whereas subjects without an impaired ankle trained a randomly selected limb.

Data at stability level 2 were analyzed independently of data at stability level 6. Data were analyzed using 2 separate 3-factor ANOVAs to determine significant interactions and main effects, and the Tukey post hoc test was used to determine significant differences between the mean values.

At level 2 (less stable), the analyzed test data indicated the following: (1) the subjects with functionally unstable ankles had poorer balance ability at the beginning of the study when compared with subjects without impairments (mean SI=5.93 [+ or -] 3.65 and 4.67 [+ or -] 3.43 respectively), (2) both groups showed improvement in posttest scores (subjects with unstable ankles: mean SI=2.63 [+ or -] 1.92; subjects without impairments: mean SI=2.69 [+ or -] 2.32), and (3) there was no difference in the posttest scores of the 2 groups. The results at level 6 (more stable) were similar, with the exception that there was no pretest difference between the groups (subjects with unstable ankles: mean SI=2.30 [+ or -] 1.88; subjects without impairments: mean SI=2.04 [+ or -] 1.43). The posttest scores at level 6 were 1.27 [+ or -] 0.66 and 1.37 [+ or -] 0.66 for the subjects with unstable ankles and the subjects without impairments, respectively. The scores in the ankle joint functional assessment tool indicated perceived improvement in ankle joint functional stability that matched improvements noted in the balance data. The post-training scores of subjects with unstable ankles (25.78 [+ or -] 3.80) and subjects without impairments (29.15 [+ or -] 5.27) improved significantly over the pre-training scores (17.11 [+ or -] 3.44 and 22.92 [+ or -] 5.22 respectively).

The researchers concluded that the 4-week training program produced a greater treatment effect for the subjects with unstable ankles than for the subjects who were not impaired. Furthermore, the researchers noted that deficits in balance ability observed in the involved limb of subjects with unstable ankles were also evident in their uninvolved limb.

Debra Coglianese, PT, OCS, ATC Beth Israel Deaconess and Children's Hospital Medical Care Center Lexington, Mass