I have painful trigger thumb with thumb dislocation found on xray. rheum wants me to wear splint/spica,but can this heal dislocation?

Hand surgeon.: I would get a second opinion with an orthopedic hand surgeon. The dislocation may need to be reduced first.

No! not unless the -: dislocation is reduced and held reduced in a stable position. Most of these require Pin Fixation and a cast to treat the dislocation. The trigger thumb can be treated with a steroid shot. If that doesn't help or if it comes back then surgery might be needed for it as well.