Comparing Rapid Spiral CT and Conventional X-ray for Reliable Detection of Peri-Prosthetic Osteolytic Lesions after Total Knee Replacement: Implications for Surgical Management

Abstract

Increasing prevalence of osteolysis-induced mechanical failure has been shown in a number of longitudinal studies after total knee replacement (TKR). It can be difficult to accurately estimate osteolytic lesions prior to surgery, even with multiplane X-rays of high quality. A model that allows more reliable lesion assessment is Surgical management is likely to be affected significantly. A simulated cadaver model was used for this study in order to compare To conventional X-ray standards, spiral computed tomography (CT) is a rapid imaging procedure for the detection of osteolytic lesions in peri-prosthetic joints after TKR. The TKR implant components were located in three human cadaveric knees, nine volume-occupying defects were created to simulate osteolytic lesions. An X-ray series of two stages and a spiral CT were employed to image the knees after implant placement. The quality of CT images was improved using a beam-hardening artefact removal algorithm. A random image sorting procedure placed 12 radiologists in the same room and asked them to independent assess whether osteolytic lesions could be seen, what anatomic location they were located in, and their size. CT images were reviewed separately using the same process. To determine if osteolytic lesions are more easily detected on X-rays and CT scans, direct comparisons of the results were performed. In a study using just AP projections (P = 0.008), CT images significantly improved recognition accuracy (P = 0.03), as did biplanar oblique X-rays (P = 0.005). Based solely on APs and laterals, the introduction of oblique images did not improve the accuracy of identifying such lesions (P = 0.13). Conclusion: An imaging method based on CT scans that is simple and rapid method can be used to reliably describe peri-prosthetic osteolytic lesions non-invasively in this study. Even when supplemental bi-planar 45° oblique views are provided, conventional X-ray is low in sensitivity and therefore cannot be used in situ for screening TKR implants for osteolytic lesions. At routine orthopaedic follow-up, CT evaluation may be a better method for evaluating osteolysis around TKRs due to its ease of use and accessibility. As a result of these findings, surgical and non-operative management strategies are influenced by the It is important to detect such lesions early and to classify them accurately, as well as the nature and appropriateness of implants revisions and joint-salvage osteotomies.