Pain, fatigue, function and transcutaneous electrical nerve stimulation in individuals with fibromyalgia

Fibromyalgia is a condition characterized by chronic widespread muscle pain and fatigue. The primary objective of this study was to determine if pain, perceived cognitive fatigue, and perceived physical fatigue were enhanced in participants with fibromyalgia compared to healthy controls during a cognitive fatigue task, a physical fatigue task and a dual fatigue task. Twenty four individuals with fibromyalgia and 32 healthy controls completed pain, fatigue and function measures. A cognitive fatigue task (Controlled Oral Word Association Test) and physical fatigue task (Valpar peg test) were done individually and combined for a dual fatigue task. Resting pain, perceived cognitive fatigue and perceived physical fatigue were assessed during each task using visual analogue scales. Function was assessed with shoulder range of motion and grip. People with fibromyalgia had significantly higher increases in pain and fatigue when compared to healthy subjects with all fatigue tasks (p<0.01). For the physical fatigue task, people with fibromyalgia performed less well when compared to healthy controls during transfer of pegs from waist to overhead (p<0.001). These data show that people with fibromyalgia show larger increases in pain and fatigue to both cognitive and physical fatigue tasks and reduced function in a physical fatigue task. Thus, how physical and cognitive activity might impact pain and fatigue is an important consideration for the clinician in terms of