Muscle Weakness and Perceived Disability of Upper Limbs in Persons With Late Effects of Polio

Muscle weakness in one or both upper limbs is common in persons with previous polio, but there is very limited knowledge how it influences daily life.

To assess muscle weakness and self-perceived disability of the upper limbs in persons with late effects of polio and evaluate their association.

Cross-sectional study.

University hospital outpatient clinic.

Twenty-eight persons (mean age 67, SD 16 years) with late effects of polio in their upper limbs.

A fixed dynamometer (Biodex System 3 PRO dynamometer (Biodex Medical Systems Inc, Shirley, NY) was used to measure isometric shoulder abduction and elbow flexion, as well as isokinetic concentric elbow flexion and extension. A hand-held dynamometer (Grippit, Hägersten, Sweden) was used to measure isometric grip strength. The Disabilities of Arm, Shoulder and Hand (DASH) questionnaire was used to assess self-perceived disability of the upper limbs. The relationships between the measures were analyzed with the Spearman rank correlation coefficients (rho).

The participants were 20%-31% weaker in their more-affected upper limb compared with their less-affected limb. The DASH score was on average 33.5 (SD 18.6), indicating a mild-to-moderate disability of their upper limbs. Changing a lightbulb overhead, carrying a heavy object, and performing recreational activities that required muscle force with the arms were perceived as most difficult. The correlations (rho) between the muscle strength measurements and DASH scores ranged from -0.46 (95% confidence interval [95% CI] -0.10 to -0.71) to -0.61 (95% CI -0.31 to -0.80) for the more affected upper limb, and from -0.54 (95% CI -0.21 to -0.76) to -0.68 (95% CI -0.41 to -0.84) for the less affected upper limb (P < .05-.01).

Persons with previous polio and muscle weakness in their upper limbs perceive difficulties to use their arms in daily life, especially when performing activities above their head and strenuous household or leisure activities. The fair-to-moderate correlations of muscle strength with self-perceived disability imply that the weakness can only partially explain the perceived disabilities of arm, shoulder and hand. Other factors are therefore important to consider in the rehabilitation of persons with late effects of polio and upper limb disability.