Do Jesus’ Post-Resurrection Scars Prove That You Will Still Have Disabilities or Disfigurements in Heaven If You Have Them Now?

No.

The fact that Jesus bore your sicknesses and diseases to purchase your healing is unopposed by Satan in heaven.  You will have a new body anyway that is not subject to pain or disease.  You will not need a walker, crutch, wheelchair or oxygen machine in heaven because you will not have any infirmities or disabilities.

Jesus was marred and disfigured “more than any man” when He was punished for our sins.

Isaiah 52:14:
As many were astonied at thee; his visage was so marred more than any man, and his form more than the sons of men:

If you still had to keep your earthly disfigurements, Jesus would still have been a physical mess after He rose from the dead.  But He wasn’t.  John described His appearance in the book of Revelation, and there was nothing to indicate that He was bruised and scarred all over.  He was bruised for our iniquities but nothing indicated that His resurrected body was full of bruises.  So you should not expect any bruises or other disfigurements to be in YOUR resurrected body in heaven.

Jesus’ bodily injuries that He showed to Thomas were not evidence that He had any disease or disability that had to remain, but rather that He had paid the price for us so that we don’t have to have them!  To Him, they are marks of honor and eternal proof of His love for us.