What can I do about my tree trunk legs which also lack skin elasticity? (photos)

Get rid of those tree trunk legs with liposuction. You will be so glad you did. They may still be dimply but the shape improvement will be so worth it.

VASER hi def lipo plus ThermiRF will help shape and define your legs as well as tighten the skin. Cellfina can be used on the backs of the thighs if you have cellulite. See an expert for a formal consultation. Best, Dr. Emer. 

best would be an in-person evaluation. but if you would like you can view some of the YouTube videos I have on my website that will help you answer some of your questions. if you wish to change the shape of your legs then a circumferential contouring is what you will need

Hello and thank you for your question. Based on your
photograph, you may be a candidate for a short scar thigh lift.  The
most important aspect is to find a surgeon you are comfortable with. I
recommend that you seek consultation with a qualified board-certified plastic
surgeon who can evaluate you in person.
Best wishes and good luck.
Richard G. Reish, M.D.
Harvard-trained plastic surgeon

The best solution for your legs is continue to exercise.  Liposuction in the thigh and knee area may help some, but it is not a cure all for legs.