In my opinion, large-joint injections/arthrograms, most abdominopelvic abscess drainages, LPs/myelograms, and uncomplicated renal/liver/thyroid/nodule biopsies should within a DR's wheelhouse. Subspecialists frequently do more (body - perc neph/biliary/chole, ports) (MSK - small joints, biopsies) (neuro - diagnostic angiography) (breast - biopsies, needle locs). Your practice is highly customizable.