Lower regulatory frequency for postural control in patients with fibromyalgia and chronic fatigue syndrome, 2018, Stensdotter et al

[Andy]

Abstract
As many similar symptoms are reported in fibromyalgia (FM) and chronic fatigue syndrome (CFS), underlying defcits may potentially also be similar. Postural disequilibrium reported in both conditions may thus be explained by similar deviations in postural control strategies. 75 females (25/group FM, CFS and control, age 19–49 years) performed 60 s of quiet standing on a force platform in each of three conditions: 1) firm surface with vision, 2) firm surface without vision and, 3) compliant surface with vision. Migration of center of pressure was decomposed into a slow and a fast component denoting postural sway and lateral forces controlling postural sway, analyzed in the time and frequency domains.

Main effects of group for the antero-posterior (AP) and medio-lateral (ML) directions showed that patients displayed larger amplitudes (AP, p = 0.002; ML, p = 0.021) and lower frequencies (AP, p < 0.001; ML, p < 0.001) for the slow component, as well as for the fast component (amplitudes: AP, p = 0.010; ML, p = 0.001 and frequencies: AP, p = 0.001; ML, p = 0.029) compared to controls. Post hoc analyses showed no significant differences between patient groups. In conclusion, both the CFS- and the FM-group differed from the control group. Larger postural sway and insufficient control was found in patients compared to controls, with no significant differences between the two patient groups.

Open access at http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0195111

 

[Trish]

In conclusion, differences in performance and postural control during quiet standing in patients with chronic fatigue syndrome and fibromyalgia varied relative to healthy controls, but with no significant differences between the patient groups.

In general, patients displayed a different pattern of postural control.
Differences in the fast and slow components was interpreted as lower regulatory frequency and greater ankle joint torque resulting in greater postural sway in patients.

Both patient groups increased the ankle torque more than controls when vision was removed, and the largest difference between healthy individuals and patients occurred when somatosensory information was modulated with vision enabled.

This suggests deficits in somatosensory information processing and possibly insufficient compensation from visual information. Findings of similar deficits in FM and CFS does however not automatically transfer to a similar origin of deficits.

I think I understand this to mean that in FM and ME, reaction to movement at the ankle when standing still that gives a clue that we are going off balance, and to visual cues, is slower than in healthy controls. And because we react more slowly to going off balance, we have to move more to re-balance, so there is a bigger, slower swaying motion - and more danger of falling.

So they are suggesting we process sensorimotor messages more slowly, and that's why we are slower to react and correct our balance.

Makes a change from being told all our physical disabilities are caused by deconditioning.