title: Early mechanical failure in total knee arthroplasty.
abstract: Early mechanical dysfunction of a total knee arthroplasty (TKA) is a challenging problem in terms of causality and solutions. The current strategy in our department is to perform a complete TKA revision rather than the less invasive partial procedures when a clear mechanical cause of failure has been found. In this investigation, we assessed 21 patients who underwent complete TKA revision in 2003-2004 in our institution within the first two years following the index TKA. Various clinical presentations included pain, stiffness, instability, and femoro-patellar signs. These corresponded to implant size, position, and fixation issues. The IKS knee score/function significantly increased from 47/47 to 85/78 at follow-up (six months minimum). Compared to the data in the literature, this systematic full revision seems to be a reasonable approach. This attitude takes advantage of the modularity of the implants for allowing perioperative adjustments of position, fixation, and constraint. Based on the results of our study, we propose a list of six mechanical pitfalls to be evaluated in the case of early dysfunction: frontal misalignment, sagittal overstuffing or malpositioning, axial malrotation, poor bone fixation, inappropriate constraint or ligamentous balance, and inappropriate level of the joint space.
authors.affiliation: Department of Orthopaedic Surgery, La Pitié Salpêtrière Hospital, Paris, France. m_a_rousseau@hotmail.com
authors.forename: Marc-Antoine
authors.initials: MA
authors.lastname: Rousseau
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Lazennec
authors.forename: Yves
authors.initials: Y
authors.lastname: Catonné
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee; D005260:Female; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure; D012086:Reoperation; D012189:Retrospective Studies; D013314:Stress, Mechanical; D013997:Time Factors; D016896:Treatment Outcome