Balance in single-limb stance after surgically treated ankle fractures: a 14-month follow-up

BACKGROUND: The maintenance of postural control is fundamental for different types of physical activity. This can be measured by having subjects stand on one leg on a force plate. Many studies assessing standing balance have previously been carried out in patients with ankle ligament injuries but not in patients with ankle fractures. The aim of this study was to evaluate whether patients operated on because of an ankle fracture had impaired postural control compared to an uninjured age- and gender-matched control group. METHODS: Fifty-four individuals (patients) operated on because of an ankle fracture were examined 14 months postoperatively. Muscle strength, ankle mobility, and single-limb stance on a force-platform were measured. Average speed of centre of pressure movements and number of movements exceeding 10 mm from the mean value of centre of pressure were registered in the frontal and sagittal planes on a force-platform. Fifty-four age- and gender-matched uninjured individuals (controls) were examined in the single-limb stance test only. The paired Student t-test was used for comparisons between patients' injured and uninjured legs and between side-matched legs within the controls. The independent Student t-test was used for comparisons between patients and controls. The Chi-square test, and when applicable, Fisher's exact test were used for comparisons between groups. Multiple logistic regression was performed to identify factors associated with belonging to the group unable to complete the single-limb stance test on the force-platform. RESULTS: Fourteen of the 54 patients (26%) did not manage to complete the single-limb stance test on the force-platform, whereas all controls managed this (p < 0.001). Age over 45 years was the only factor significantly associated with not managing the test. When not adjusted for age, decreased strength in the ankle plantar flexors and dorsiflexors was significantly associated with not managing the test. In the 40 patients who managed to complete the single-limb stance test no differences were found between the results of patients' injured leg and the side-matched leg of the controls regarding average speed and the number of centre of pressure movements. CONCLUSION: One in four patients operated on because of an ankle fracture had impaired postural control compared to an age- and gender-matched control group. Age over 45 years and decreased strength in the ankle plantar flexors and dorsiflexors were found to be associated with decreased balance performance. Further, longitudinal studies are required to evaluate whether muscle and balance training in the rehabilitation phase may improve postural control

Individual factors affecting stabilometry and one-leg hop test in 75 healthy subjects, aged 15-44 years

The aims of this study were: 1) to investigate whether single-limb stabilometry and a one-leg hop test are influenced by age, sex, height, weight or activity level in healthy subjects, 2) to examine possible differences between the right and the left leg, 3) to determine Limb Symmetry Index (LSI) values, and 4) to study the relation between the stabilometric variables, that is, average speed (AS) and amplitude of center of pressure (CP) movements. Seventy-five healthy subjects (39 women) were studied, with a mean age of 29.5 years (SD 8.2, range 15-44), mean height 175 cm (SD 8.6, range 155-194), mean weight 67.8 kg (SD 9.7, range 50-90) and median value 8 (quartiles 8-9, range 7-10) on a 1-10 activity-level scale. AS was higher among the men compared to the women and increased with increasing age. The females hopped shorter distances than the males. The hop distance decreased with increasing age among the women. Height, weight and activity level within the actual range had no significant influence on stabilometric or hop-test values. When comparing patients with healthy subjects, they should be matched according to sex and age, with an age difference of less than 10 years within pairs