Patient with right total knee arthroplasty with but with substantial pain/dysfunction at level of patellar tendon insertion. Has either scar or other substance irritating patellar tendon or intrasubstance tendinitis of tendon. Total knee arthroplasty was implanted in 2013, is made of chrome-cobalt allow, and x-rays indicate it is well fixed. Evaluation of the bones and soft tissues of the knee is limited due to metallic susceptibility artifact arising from the patient's total knee arthroplasty. The extensor mechanism is best seen on the MAVRIC sequences: series 7, 9, and 11. The patellar tendon appears intact. There is minimal increased signal intensity within the proximal fibers of the patellar tendon at its attachment to the patella which could conceivably represent mild tendinosis, but the true clinical significance of this is uncertain. I see no frank edema within the adjacent patella or the anterior tibial tubercle. There is bandlike low signal intensity along the posterior margin of Hoffa's fat pad, extending from the undersurface of the patella to the anterior aspect of the proximal tibial component, likely representing postoperative scarring, but this not does not appear to directly involve the patellar tendon. Minimal, thin bandlike intermediate signal intensity extends from the anterior margin of the tibial component to the patellar tendon (image 14 of series 9) which may reflect mild scarring, but this is of questionable clinical significance. The visualized components of the quadriceps tendon appear normal. There is a small amount of fluid in the joint. There are foci of metallic stability artifact anterior to the distal quadriceps tendon and patellar tendon likely representing suture material. The remaining visualized soft tissue structures are unremarkable. Visualized bone marrow signal intensity is likewise within normal limits. The susceptibility artifact from the patient's total knee arthroplasty precludes evaluation of enhancement along the patellar tendon and in the soft tissues adjacent to the prosthesis; no abnormal enhancement is noted in the tissues proximal and distal to the prosthesis.
There is perhaps minimal proximal patellar tendinosis and subjacent scarring, but I see otherwise see no specific findings to account for the patient's symptoms.