I dislocated my elbow when I was younger and when they set my arm .. My left is2mm approx shorter than my right and the curve when straightened is slightly different.

I haven't trained in a couple of years due to other issues, anyway when I hit the gym this morning I found my left arm to be weaker than my right in all exercises. .. Bicep curls, dumbbell flies etc.i also know that tomorrow I'm going to have stiffness in that joint... Is there anyway I can strengthen this so its not an issue?