With complete rest, frozen shoulder will heal in about 24 months. However, the body doesn't completely rest: we breath, sneeze, move, talk, eat, drink which means that however small an action, the upper body does move. Steroid injections can ease symptoms, it's like a bit of WD40
. Gentle exercise to stop the muscle over the joint ceasing up more can help, Mum had to lean forwards and make a 'stirring the pudding' action as well as reaching up as far as she could. MinL suffered too. At that 'certain' age