title: Force-controlled dynamic wear testing of total ankle replacements.
abstract: Currently, our knowledge of wear performance in total ankle replacements is limited. The aim of this study is to develop a scenario for force-controlled testing and wear testing of total ankle replacements. A force-controlled wear test was developed: based on cadaver measurements, the passive stabilization (ligaments and soft tissue) of the ankle joint was characterized and a restraint model for ankle stabilization was developed. Kinematics and kinetics acting at the replaced ankle joint were defined based on literature data and gait analysis. Afterwards, force-controlled wear testing was carried out on a mobile, three-component, total ankle replacement design. Wear was assessed gravimetrically and wear particles were analyzed. Wear testing resulted in a mean wear rate of 18.2±1.4mm(3)/10(6) cycles. Wear particles showed a mean size of 0.23μm with an aspect ratio of 1.61±0.96 and a roundness of 0.62±0.14. Wear testing of total ankle replacement shows that a relevant wear mass is generated with wear particles in a biologically relevant size range. The developed wear test provides a basis for future wear testing of total ankle replacements.
authors.affiliation: Laboratory of Biomechanics and Implant Research, Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, 69118 Heidelberg, Germany. Electronic address: joern.reinders@med.uni-heidelberg.de.
authors.forename: Jörn
authors.initials: J
authors.lastname: Reinders
authors.affiliation: Laboratory of Biomechanics and Implant Research, Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, 69118 Heidelberg, Germany.
authors.forename: Falko
authors.initials: F
authors.lastname: von Stillfried
authors.affiliation: Laboratory of Biomechanics and Implant Research, Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, 69118 Heidelberg, Germany.
authors.forename: Emel
authors.initials: E
authors.lastname: Altan
authors.affiliation: Laboratory of Biomechanics and Implant Research, Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, 69118 Heidelberg, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Sonntag
authors.affiliation: Heidelberg Movement Analysis Lab, Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, 69118 Heidelberg, Germany.
authors.forename: Daniel W W
authors.initials: DWW
authors.lastname: Heitzmann
authors.affiliation: Laboratory of Biomechanics and Implant Research, Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, 69118 Heidelberg, Germany.
authors.forename: Jan Philippe
authors.initials: JP
authors.lastname: Kretzer
mesh_terms: D058737:Arthroplasty, Replacement, Ankle; D001696:Biomechanical Phenomena; D006801:Humans; D008422:Materials Testing
keywords: Ankle arthroplasty; Ankle replacement; Wear; Wear particles; Wear simulation