Hand dysfunction is a frequent cause of disability in rheumatoid arthritis (RA). In patients with RA, we studied the precision grip-lift sequence in relation to pain, stiffness, and observer assessed hand function and their relation to patients' experience of clumsiness and tendency to drop objects.
Performance of the precision grip-lift sequence was studied in 23 women with RA and 7 age and sex matched controls. The results were correlated to self-estimation of pain and stiffness of hands and to observer assessed measurements of hand function.
A prolongation of the preload and loading phases and of the acceleration part of the transition phase as well as a disturbance of the safety margin (SM) during precision grip-lift were noted. Patients with good hand function (low Grip Ability Test score; GAT) displayed normal or increased SM compared to the healthy controls, whereas patients with more pronounced disease exhibited a lower SM. Disturbances seen in the precision grip-lift performance were related to stiffness, range of motion, and GAT score. In RA patients with decreased hand function the SM was correlated to feeling of clumsiness, but did not explain the frequency of object dropping.
A disturbance in the precision grip-lift performance was noted in patients with RA. These grip performance changes need further investigation to determine possible mechanisms.