Metacarpophalangeal impairment in hand osteoarthritis is not rare and is associated with mechanical factors: Results from the DIGICOD hand osteoarthritis cohort

Hand osteoarthritis: A fresh look

Hand osteoarthritis (OA) has been the subject of numerous publications in recent years, particularly in the fields of imaging and therapeutics. The imaging studies revealed a good correlation between the presence of synovitis and/or subchondral edema and arthritic joint pain. Several randomized controlled trials (RCTs) have assessed the efficacy of biologics and conventional DMARDs in patients with symptomatic hand OA. No less than six RCTs have evaluated the symptomatic and, in some cases, structural efficacy of anti-IL-1, anti-TNF or anti-IL-6 drugs. Overall, the results of these trials were disappointing - none of them demonstrated superiority over placebo. There were also two negative trials with hydroxychloroquine. In the end, the only trial that was positive evaluated 10mg oral prednisone versus placebo for 6 weeks in patients with flares of hand OA and synovitis visible on ultrasound. While that trial confirms the role of inflammation in hand OA, it should obviously not encourage the long-term use of corticosteroids as a symptomatic treatment.

Using Sensorized Gloves and Dimensional Reduction for Hand Function Assessment of Patients with Osteoarthritis

Sensorized gloves allow the measurement of all hand kinematics that are essential for daily functionality. However, they are scarcely used by clinicians, mainly because of the difficulty of analyzing all joint angles simultaneously. This study aims to render this analysis easier in order to enable the applicability of the early detection of hand osteoarthritis (HOA) and the identification of indicators of dysfunction. Dimensional reduction was used to compare kinematics (16 angles) of HOA patients and healthy subjects while performing the tasks of the Sollerman hand function test (SHFT). Five synergies were identified by using principal component (PC) analyses, patients using less fingers arch, higher palm arching, and a more independent thumb abduction. The healthy PCs, explaining 70% of patients’ data variance, were used to transform the set of angles of both samples into five reduced variables (RVs): fingers arch, hand closure, thumb-index pinch, forced thumb opposition, and palmar arching. Significant differences between samples were identified in the ranges of movement of most of the RVs and in the median values of hand closure and thumb opposition. A discriminant function for the detection of HOA, based in RVs, is provided, with a success rate of detection higher than that of the SHFT. The temporal profiles of the RVs in two tasks were also compared, showing their potentiality as dysfunction indicators. Finally, reducing the number of sensors to only one sensor per synergy was explored through a linear regression, resulting in a mean error of 7.0°.