“Systematic reviews of controlled clinical studies of treatments used by chiropractors have found no evidence that chiropractic manipulation is effective, with the possible exception of treatment for back pain.[8] A 2011 critical evaluation of 45 systematic reviews concluded that the data included in the study “fail[ed] to demonstrate convincingly that spinal manipulation is an effective intervention for any condition.”[10] Spinal manipulation may be cost-effective for sub-acute or chronic low back pain, but the results for acute low back pain were insufficient.[11] No compelling evidence exists to indicate that maintenance chiropractic care adequately prevents symptoms or diseases.[12]”
I think you’re misunderstanding what most of them keep practicing. It’s not the kooky cranial/cervical manipulation(you can make an argument that them having to learn that stuff in the first place is BS and a waste of time), but most do pick up a few muscle pressure point tricks and stretches that are essentially the same as what PT instructs patients on how to do. Is it bullshit? No more so than most medicine that’s practiced(the data behind the vast majority of what your average physician does is at best all over the place, the truly “settled” clinical questions are few and far between). In my book though, anything that keeps you from having to prescribe a scheduled drug (read as:narcotic or muscle relaxer) to get someone functional from something like severe trapezius tightness or piriformus syndrome is a heck of a tool to have at your disposal in a primary care or urgent care setting.