Overactive platysma muscle - what can be done? (Photos)

Hi there!
It looks as though you could benefit from tightening (or re-tightening) the muscles of the neck ("platysmaplasty") along with a neck lift and/or lower facelift. The decision on whether or not to do the neck alone, without the face, depends on your goals and anatomy. You do not need to go for the facelift to be able to address the neck muscle–you can do that with the neck lift alone.
I hope this answers your question!

This is a combination of scarring and platysmal banding. You can see the edges of the platysma muscle which appear as the vertical lines going from the chin to the collar bone area. You can also see a very slight prominence of the submandibular gland. You are correct in that this revision would be challenging and needs to be done by an expert plastic surgeon (American Board of Plastic Surgery certified). This surgeon needs to have experience in revisionary facelift/necklift surgery. I would recommend another necklift that would permit addressing the bands, releasing the tethered scarred skin, reducing the gland and then contouring with any additional maneuvers that might be required to help smoothen the neck in the area.

This is relatively frequent finding after neck lift surgery regardless whether resection of platysma muscle in the anterior neck was performed after platysmoplasty. If correction with Botox does not create improvement, revision neck surgery with release of skin and muscle adhesions, possibly further excision of the platysma muscle may be considered. This can be done in local or twilight anesthesia. Good luck.