Isometric middle finger abduction (2nd dorsal interosseous) (Finger (middle) abduction strengthening isometric - 2nd dorsal interosseous)

Sit upright in a chair.
Place your affected arm on a table with your palm facing down and your fingers flat.
Place the index finger from your unaffected hand on the thumb side of your middle finger.
Try to move your middle finger towards your thumb, using your opposite hand to resist the movement.
Keep your palm and forearm flat on the table throughout the exercise.