Both terms are interchangeably used to refer to the same surgical procedure but there is a difference. If we delve deeper, Arthroplasty is a broad term that refers to multiple surgical reconstructions or replacements of a joint, while joint replacement only refers to the removal of a damaged joint and replacement with an artificial joint or prosthesis.
With this, we can say that joint replacement surgery is a type of arthroplasty, but not all arthroplasty procedures involve joint replacement. For example, arthroscopic surgery, which involves repairing or removing damaged tissue in a joint through small incisions, is also a type of arthroplasty but does not involve joint replacement. The long and short of it is that while joint replacement is a type of arthroplasty, arthroplasty encompasses a broader range of surgical techniques for joint reconstruction or replacement.