Can knitting aggravate the rotator cuff? I have impingment & it seems 2 be getting more sore since knitting

Potentially. Traditionally impingement/rotator cuff tendinopathy is aggravated by overhead activity, but if your getting symptoms while knitting, then that may be an activity that aggravates pain in the shoulder. I would recommend staying away from activities that hurt your shoulder.
Yes. I have had multiple patients who complained that knitting causes increased pain. I think it has to do with arm position. I do not think it will cause any further physical damage, but it may increase pain. Try changing positions. Thank you.