The Single-Leg-Stance Test in Parkinson’s Disease

Abstract

BackgroundTimed single-leg-stance test (SLST) is widely used to assess postural control in the elderly. In Parkinson’s disease (PD), it has been shown that an SLST around 10 seconds or below may be a sensitive indicator of future falls. However, despite its role in fall risk, whether SLST times around 10 seconds marks a clinically important stage of disease progression has largely remained unexplored.MethodsA cross-sectional study where 27 people with PD were recruited and instructed to undertake timed SLST for both legs was conducted. Disease motor impairment was assessed with the Unified Parkinson’s Disease Rating Scale Part 3 (UPDRS-III).ResultsThis study found that: 1) the SLST in people with PD shows good test-retest reliability; 2) SLST values can be attributed to two non-overlapping clusters: a low (10.4 ± 6.3 seconds) and a high (47.6 ± 11.7 seconds) value SLST group; 3) only the low value SLST group can be considered abnormal when age-matched normative SLST data are taken into account for comparison; and 4) lower UPDRS-III motor performance, and the bradykinesia sub-score in particular, are only associated with the low SLST group.ConclusionThese results lend further support that a low SLST time around 10 seconds marks a clinically important stage of disease progression with significant worsening of postural stability in PD.

Comparing postural balance among older adults and Parkinson's disease patients

“…Additionally, single-legged support may be more appropriate to provide additional information when assessing balance and determining potential disorders, as individuals may not be challenged sufficiently when performing two-legged tests 2,23,24 . In this context, Chomiak and collaborators verified in their study that not being able to remain in a single-leg stance for at least 10 seconds is related to an increased risk of falling among individuals with PD 25 . This study's main findings reveal that the PG presented a worse performance in the COP area represented by an oscillation of more than 60% when compared to the group of healthy individuals (P = 0.002).…”

“…These results are in agreement with our study's findings in regard to balance among PD individuals 30 . We emphasize that we use the single-leg stance in our research in order to provide more appropriate information about balance, as individuals cannot be challenged enough when subjected to tests in bipedal stance 25 . Moreover, there are few studies that evaluated individuals with PD under single-leg stance conditions 31,32,33 and these studies did not use similar methodology, making it difficult to compare our data.…”

Outcome on Balance and Gait Following Botulinum Toxin Treatment for Striatal Foot in Parkinson's Disease

“…Notably, in 30% of individuals, the difference between each leg in OLS performance ranged from 11 to 55 seconds . However, variations are wide in the ability of patients with PD to stand on 1 leg, and there does not seem to be any correlation between motor function and this ability . A correlation does exist, however, between the side of striatal foot deformity and the side of initial parkinsonian symptoms .…”

“…This improvement may have important clinical implications, because an OLS performance time of 10 seconds or less is associated with an increased risk of falling in PD . However, in a recently published PD study, the OLS test was conducted for both legs and was executed for up to 60 seconds. Notably, in 30% of individuals, the difference between each leg in OLS performance ranged from 11 to 55 seconds .…”

“…However, in a recently published PD study, the OLS test was conducted for both legs and was executed for up to 60 seconds. Notably, in 30% of individuals, the difference between each leg in OLS performance ranged from 11 to 55 seconds . However, variations are wide in the ability of patients with PD to stand on 1 leg, and there does not seem to be any correlation between motor function and this ability .…”