Current applications of advanced cross-sectional imaging techniques in evaluating the painful arthroplasty.

Patients with a painful arthroplasty can present a clinical diagnostic dilemma. Aspirates are often negative for infection and alignment of the prosthesis on conventional radiographs is usually satisfactory. These patients can have a myriad of soft tissue as well as osseous pathologies, which may be clinically unsuspected or radiographically occult. The ability of advanced cross-sectional imaging to diagnose osseous and soft tissue injuries has been well documented, but applications to arthroplasty imaging are often limited by regional metallic artifacts. Adjustment of standard imaging parameters can make CT and MR imaging useful adjuncts in imaging the painful arthroplasty, especially in the setting of normal radiographs. Ultrasound can be used to evaluate the periprosthetic soft tissues and provide a real-time method of evaluating the dynamic relationship of the periprosthetic soft tissues to the arthroplasty components, and it also can be used as a guide for diagnostic and therapeutic interventions.