[Evaluation of balance in neurologic and geriatric disorders]

Abstract

Objective: To analyse the clinical usefulness and metrological properties of the main techniques and indices used to assess balance disorders.

Methods: More than 4000 abstracts referenced in MEDLINE and dealing with postural control and postural disorders (wide screening) were reviewed to determine the main postural techniques and indices used in a clinical context. We retained abstracts with a high citation frequency and those with interesting findings. Corresponding key words were identified for a specific search of articles that we analysed.

Results: Postural assessment tools can be classified as scales of ordinal items, tests based on metric or chronometric measurement, posturography, and verticality perception. These techniques are complementary, and their association is recommended in a clinical context. Regarding generic tools, the Falls-related Efficacy Scale (FES) and the Activities-specific Balance Confidence scale (ABC scale) would be enhanced if comparatively analysed and reworked to allow for a feasible and reliable assessment of the fear of falling. Despite a wide diffusion in numerous postural fields worldwide, the Berg Balance Scale (BBS) and the Functional Reach Test (FRT) do not have the required criteria to remain the gold standards they were in the 1990s. Static posturography should be normalised and yield more reliable indices. The clinical relevance of the subjective assessment of visual, haptic, and postural verticals are questionable, especially to explain postural disability. Regarding specific tools, the Tinetti test (TT) and the Time Up and Go test (TUG) are the most suited to assess postural capacities in very elderly people, in whom the predictive validity of the postural assessment of falls is still modest. In stroke patients, the Postural Assessment Scale for Stroke (PASS), posturography, lateropulsion assessment, and vertically perception are interesting and complementary techniques. Postural assessment relies mainly upon the 5 postural items of the Unified Parkinson Disease Rating Scale (UPDRS) in people with Parkinson disease and upon the Romberg test and posturography in patients with cerebellar or proprioceptive ataxia. Some novel postural scales for patients with multiple sclerosis or spinal cord injury are also emerging.

Conclusion: Among numerous tools that contribute to the assessment of postural disorders, only the most recent ones (developed in the last 10 years) have undergone complete validation. It is now crucial to compare these tools, not only in terms of reproducibility and internal consistency, but also overall, in terms of feasibility, responsiveness, and predictive validity for a given population.