Background Postural control, that depends on many sensory contributors and motor skills, is altered in people with fibromyalgia (FM) 1–3. Knowing those contributors that could be impaired in this population is important to design an appropriate balance therapy.
Objectives Due to the fact that people with FM use to present a strength loss 7, our main goal was to explore the relation between postural control and lower limb strength in this population. Further, the sensory inputs contributors to the postural control were assessed.
Methods A cross-sectional study was conducted in a sample of 40 FM patients. A force platform was used to assess postural control under five bipedal conditions: i) eyes-open (EO); ii) dual task (recalling a typical day in their life) (DT); iii) eyes-close (EC); iv) eyes-open over a foam (FEO); v. eyes-close over a foam (FEC). Three variables, “Ellipse”, “RMS” and “Sample Entropy” (SampEn), were recorded (for both directions). Further, maximal quadriceps (qdc) and hamstring (hmsg) isometric strength were assessed using a dynamometer. Spearman correlations were conducted to establish the relationship between postural control and strength and a repeated-measures MANOVA, to analyze differences between conditions.
Results When EO and DT (performed with eyes open) were compared, no significant differences were obtained. However when patients closed their eyes, an increase in ellipse and RMS_AP and a decrease in variability were obtained. The same was true when the tests were performed over a foam (altering proprioception), Table 1.
Furthermore, no significant correlations (p>0.05) were observed between strength and balance except for a weak significant correlation between hmsg strength and RMS_AP (rs=-0.33, p<0.05) in the EC test.
Conclusions Postural control worsens in FM people when some sensory inputs are altered or missed. Further, there is no correlation between lower limb strength and balance in this population.
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Acknowledgements Grant GV2016/140. Conselleria Educaciό Ciencia i esports. Valencia, Spain.
Disclosure of Interest None declared