对常规治疗无效的手部骨关节炎的甲氨蝶呤治疗 (ADEM2)

The placebo consists of a 0.9% solution of sodium chloride (NaCl) in sterile distilled water for injection. This solution was chosen as the placebo. Injection every week during 12 month.

Injection of methotrexate every week during 12 month

The progression of structural damage between M0 and M12, the worsening of digital osteoarthritis in a joint, will be defined by the change in stage of the Verbruggen-Veys score. The Verbruggen-Veys anatomical scoring system for hand osteoarthritis, which evaluates the radiographic progression of interphalangeal joints.

This scale classifies each joint into five stages (N, S, J, E, R) reflecting increasing severity of structural damage. Progression is defined as a transition to a more advanced stage between M0 and M12.

As this is a categorical ordinal scale rather than a continuous numerical score, there are no minimum or maximum numerical values. However, higher stages correspond to more severe structural damage and thus a worse outcome.

Hand function will be assessed using the Australian/Canadian Osteoarthritis Hand Index (AUSCAN). The AUSCAN is a validated patient-reported outcome measure that evaluates pain, stiffness, and physical function in hand osteoarthritis. The function subscale consists of 9 items, each scored on a Likert scale. The total function score ranges from 0 to 36, with higher scores indicating worse functional impairment. Changes in the AUSCAN function score between baseline (M0) and 12 months (M12) will be analyzed.

The effectiveness of the treatment on pain will be assessed using a Visual Analog Scale (VAS) for pain, a validated patient-reported outcome measure.

The VAS consists of a 100 mm horizontal line, where 0 mm indicates "no pain" and 100 mm indicates "worst imaginable pain".

The outcome will be expressed as the mean pain score (in millimeters) and the change in pain score from baseline (M0) at each time point (M3, M9, and M12).

Higher scores indicate greater pain intensity and therefore a worse outcome.