Pressure algometry and palpation of the upper limb peripheral nervous system in subjects with hand osteoarthritis are repeatable and suggest central changes

Case-control study. A subset of patients with hand osteoarthritis (OA) shows evidence of central pain phenotypes. To examine whether differences exist in experimental pain responses in the affected and nonaffected sides of patients with unilateral hand OA. To investigate the test-retest reliability of pressure algometry and manual digital palpation in patients with unilateral hand OA. The hand OA group consisted of 20 patients, and the control group consisted of 20 healthy subjects. Pressure pain threshold (PPT) measurements were made 2 times, consisting of 3 repeat trials, each using computerized algometry and manual digital palpation. Grip and key strength (dynamometer), pain (visual analog scale), and function (Disabilities of the Arm, Shoulder and Hand [short version]) were also measured. The 2-way analysis of variance was conducted to determine the differences between sides and groups. Intraclass correlation coefficient (ICC) and standard error of measurement were calculated. Patients with hand OA had decreased PPTs over the thumb carpometacarpal joint as well as radial and median nerves compared with controls (all P