Capsaicin in Digital Osteoarthritis Versus Control

Inclusion Criteria: * Diagnosis of digital osteoarthritis fulfilling the American College of Rheumatology criteria; * Presence of finger pain of ≥ 40 mm on a visual analogue scale (VAS); * Presence of finger pain with a neuropathic pain component (DN4 score ≥ 4/10) * Inadequate response, adverse reactions, and/or contraindications to conventional analgesics and NSAIDs; Exclusion Criteria: * Patient with isolated rhizarthrosis; * Patient with other joint disease affecting the fingers (gout, chondrocalcinosis, RA, spondyloarthritis, psoriatic arthritis); * Patient with upper extremity pain syndrome that may interfere with the assessment of finger pain; * Patient with another pathology responsible for neuropathic hand pain (carpal tunnel syndrome, diabetic neuropathy, Guyon's tunnel syndrome, cervicobrachial neuralgia, brachial plexitis); * Patient with skin lesions on the fingers (psoriasis, wounds, chronic ulcers, eczema, shingles, dermatitis); * Patient with poorly controlled high blood pressure; * Patient with hypersensitivity to capsaicin; * Patient who had 8% capsaicin patch use in the year prior to the study; * Patient who has received intramuscular, intra-articular or intravenous corticosteroid therapy, another disease-modifying anti-rheumatic therapy (methotrexate, salazopyrine) or an intra-articular injection into the joints of the fingers within the previous 3 months; * Patient wearing wrist or finger orthoses in the previous month; * Patient with fibromyalgia;