Evaluation of minimum pinch force while holding in fbromyalgia patients

Objective This study aimed to investigate the relationship between the minimum pinch force applied during object carrying and physical fatigue in patients with fbromyalgia. For this purpose, the study evaluated the association between the minimum and maximum pinch forces exerted while carrying a weight and both isokinetic muscle strength and the isokinetic fatigue index. Methods One hundred eight (54 FMS/54 healthy) women participated. Pinch force was measured with a force sensor, and wrist fexor/extensor strength and fatigue index were evaluated using an isokinetic dynamometer at 180°/s. Results Minimum pinch force did not difer signifcantly between groups, but maximum pinch force was higher in healthy subjects (p=0.011). Wrist fexor and extensor strength were substantially lower in FMS (p<0.001 for both). Fatigue index was lower in FMS, but diferences were not statistically signifcant (p=0.05, p=0.06). In FMS patients, the minimum pinch force correlated with wrist fexor and extensor fatigue, but no correlation was found in controls. Conclusions Our research shows that the minimum pinch force exerted by women with FMS is not diferent from that exerted by healthy women, but the maximum pinch force is lower. Muscle performance tests measured by isokinetic dynamometry may help assess physical fatigue in FMS patients. Signifcance Although women with FMS can match their healthy peers in minimum pinch force, their lower maximum force may be the main cause of the fatigue they experience during daily activities.