title: Intravertebral neotrabecularization as an expression of focal load transfer by a keel-design lumbar total disc arthroplasty.
abstract: The aim of this study is to direct attention to the specific load transfer characteristics of keel-design total disc arthroplasty (TDA) implants that may be underreported. A variety of implants for lumbar TDA are available on the market. One of the main differences between the design types of lumbar TDA implants is whether they use a keel or small spikes/ridges in order to achieve primary stability. The consequences of such design features on load transfer have not been adequately discussed. We report and discuss a case in which new intravertebral bone trabecula have appeared after double-level implantation of a keel-based TDA. We think that the mid- and long-term follow-up radiographs of patients after TDA with keel-design implants should be examined for the presence or absence of such changes. Should our case turn out to be not a singular occurrence, this might have an impact on the design of future TDA implants.
authors.affiliation: Department of Orthopedic Surgery, Grosshadern Medical Center, Ludwig-Maximilian-University Munich, Marchioninistr. 15, 81377 Munich, Germany. doctor-b@web.de
authors.forename: Christof
authors.initials: C
authors.lastname: Birkenmaier
authors.forename: Bronek
authors.initials: B
authors.lastname: Boszczyk
authors.forename: Andrea
authors.initials: A
authors.lastname: Baur-Melnyk
authors.forename: Bernd
authors.initials: B
authors.lastname: Wegener
authors.forename: Volkmar
authors.initials: V
authors.lastname: Jansson
mesh_terms: D000328:Adult; D016723:Bone Remodeling; D005260:Female; D006801:Humans; D007595:Joint Prosthesis; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000502:physiology*; D011474:Prosthesis Design; D011859:Radiography; D059145:Total Disc Replacement; D016474:Weight-Bearing