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Polymethylmethacrylate (PMMA) removal during septic total joint arthroplasty revision is associated with a high fracture and perforation risk. Ultrasonic cement removal is considered a bone‐preserving technique. Currently, there is still a lack of sound data on efficacy as it is difficult to detect smaller residues with reasonable technical effort. However, incomplete removal is associated with the risk of biofilm coverage of the residue. Therefore, the study aimed to investigate the efficiency of ultrasonic‐based PMMA removal in a human cadaver model. The femoral components of a total hip and a total knee prosthesis were implanted in two cadaver femoral canals by 3rd generation cement fixation technique. Implants were then removed. Cement mantle extraction was performed with the OSCAR‐3‐System ultrasonic system (Orthofix®). Quantitative analysis of cement residues was carried out with dual‐energy and microcomputer tomography. With a 20 µm resolution, in vitro microcomputer tomography visualized tiniest PMMA residues. For clinical use, dual‐energy computer tomography tissue decomposition with 0.75 mm resolution is suitable. With ultrasound, more than 99% of PMMA was removed. Seven hundred thirty‐four residues with a mean volume of 0.40 ± 4.95 mm3 were identified with only 4 exceeding 1 cm in length in at least one axis. Ultrasonic cement removal of PMMA was almost complete and can therefore be considered a highly effective technique. For the first time, PMMA residues in the sub‐millimetre range were detected by computer tomography. Clinical implications of the small remaining PMMA fraction on the eradication rate of periprosthetic joint infection warrants further investigations. [ABSTRACT FROM AUTHOR]

High speed cutting and ultrasound devices for cement extraction from the femoral cavity in hip revision procedures are frequently used. Such devices generate heat at the cutting interface which may damage osteocytes. One ultrasound device, a manual high-speed cutter and a robot-based high-speed cutter were tested in human cadaveric bone at body temperature. Temperature probes were placed at the cement-bone interface, and data collected from 12 sensors with a digital data-logger during cement removal from the femoral cavity. Peak temperatures from each sensor were recorded and compared by Kruskal- Wallis-H-Test for global effect and Mann-Whitney-U-Test for multiple comparisons. All devices generated mean temperature peaks of over 50°C which is above levels considered safe. A peak temperature of 164°C was reached by the ultrasound system. Significant differences between the three devices exist, with the ultrasound generating the highest median peak temperatures of 107°C. The lowest median peak temperature of 65°C was generated by the high-speed cutting system. Major improvements of the irrigation and cooling systems of the devices seem to be necessary. [ABSTRACT FROM AUTHOR]