Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

Polymethylmethacrylate (PMMA) removal during septic total joint arthroplasty revisionis associated with a high fracture and perforation risk. Ultrasonic cement removal isconsidered a bone‐preserving technique. Currently, there is still a lack of sound data onefficacy as it is difficult to detect smaller residues with reasonable technical effort.However, incomplete removal is associated with the risk of biofilm coverage of theresidue. Therefore, the study aimed to investigate the efficiency of ultrasonic‐basedPMMA removal in a human cadaver model. The femoral components of a total hip and atotal knee prosthesis were implanted in two cadaver femoral canals by 3rd generationcement fixation technique. Implants were then removed. Cement mantle extraction wasperformed with the OSCAR‐3‐System ultrasonic system (Orthofix®). Quantitativeanalysis of cement residues was carried out with dual‐energy and microcomputertomography. With a 20 μm resolution, in vitro microcomputer tomography visualized tiniest PMMA residues. For clinical use, dual‐energy computer tomography tissuedecomposition with 0.75 mm resolution is suitable. With ultrasound, more than 99% ofPMMA was removed. Seven hundred thirty‐four residues with a mean volume of0.40 ± 4.95 mm3were identified with only 4 exceeding 1 cm in length in at least oneaxis. Ultrasonic cement removal of PMMA was almost complete and can therefore beconsidered a highly effective technique.For the first time, PMMA residues in thesub‐millimetre range were detected by computer tomography. Clinical implications ofthe small remaining PMMA fraction on the eradication rate of periprosthetic jointinfection warrants further investigations.