I agree with LisaM, that it may very well be just weak muscles from lack of use for so long. But please don't push things too far - no pain, no gain DOESN"T work for TOSERS! Maybe start out walking the wall 3 times (high as you can, but don't push past discomfort to PAIN) in a.m., 3 times in p.m.

Also do plenty of nerve glides - ask your PT to show you. Your muscles may have been cut off from their power supply - the nerves - due to TOS - and the nerves will take a bit longer to wake up. About 6 wks out from surgery you will feel when the nerves start waking up - they will tingle, be angry, flare easily, etc. But that is all to the good - now you will have good power supply to those muscles.

Baby steps...you didn't get here overnight, you can't undo it overnight. But if you aren't happy with your progress or your PT in 4-6 weeks or so, can't see you've made any ground, may want to look for a new PT, there are few who really understand rehabbing from TOS surgery.

Best wishes,
beth