Imaging of Total Knee Arthroplasty

Abstract

Painful total knee arthroplasty (TKA) represents a diagnostic challenge for the clinician and radiologist, as there is a wide variety of potential etiologies, with a broad range of clinical presentations, and the abnormalities on imaging studies are often subtle, absent, or nonspecific. Imaging findings of normal TKA are reviewed, in addition to a variety of complications such as loosening, infection, instability, osteolysis, heterotopic ossification, extensor mechanism disruption, and fracture. Although imaging evaluation of painful TKA is usually limited to conventional radiographs and nuclear imaging, examples of the utility of computed tomography are also illustrated, and suggested imaging strategies and algorithms are discussed.

Varus Di̇zi̇li̇m Bozukluğu Ve Pri̇mer Osteoartrozlu Di̇zlerde Total Di̇z Protezi̇ Sonrasi Proksi̇mal Ti̇bi̇ofi̇bular Kaynakli Ağri Hasta Mutsuzluğuna Neden Mi̇?

“…Knees with gross instability and painful lateral retinaculum and/or PF joint were excluded from the study. Antero-posterior and lateral radiographs of the knee were evaluated to reveal evident findings of component loosening (wider and more extensive zone(s) of lucency around the components, and component migration) and lateral overhang of the tibial base plate, which were exclusion criteria (8,9). Inclusion criteria for the study are shown in Table 1.…”

Berliner diagnostischer Algorithmus der schmerzhaften Knie-TEP

“…Radiologisch zeigen sich meist klare Lockerungszeichen in Form von Saumbildungen. Eine durchgehende Ausdehnung > 2 mm oder eine zeitliche Progredienz sind beweisend für eine aseptische Lockerung [27][28][29]. Davon abzugrenzen sind radiolucent lines.…”

“…Dabei handelt es sich um knöcherne Reaktionen, die häufig als Lockerungssaum fehlinterpretiert werden. Sie treten vor allem bei unikondylären Endoprothesen und Revisionsimplantaten auf [29,30]. Während der echte Lockerungssaum über die Zeit progredient ist, zeigen die radiolucent lines keine Zunahme.…”

“…Während der echte Lockerungssaum über die Zeit progredient ist, zeigen die radiolucent lines keine Zunahme. Die häufig zur Lockerungsdiagnostik eingesetzte 3-Phasen-Skelettszintigrafie ist aufgrund der geringen Spezifität nur wenig hilfreich [29]. Innerhalb der ersten 12-18 Monate nach Implantation ist eine Differenzierung zwischen Lockerung und Remodelling des Knochens in der Skelettszintigrafie unmög-lich [31].…”

Imaging patellar complications after knee arthroplasty

“…Although no studies have addressed the routine use of these techniques for the follow-up of asymptomatic patients, some authors recommend CT to look for osteolysis in patients with painful knee prostheses with normal or equivocal radiographs and increased uptake on all three phases of a bone scan. [6] Another group of researchers [7]- [8] recommend multidetector CT in cases where osteolysis is likely, such as those with aseptic loosening and gross polyethylene wear. In patients with loosening, CT examination may also be useful to show the extent and width of lucent zones that may be less apparent on radiographs; in these cases, CT makes it possible to assess rotational alignment of components and to detect subtle or occult periprosthetic fractures of the patella.…”