Symptomatic Flexion Instability in Posterior Stabilized Primary Total Knee Arthroplasty
Publication Date
2014
Journal Title
Orthopedics
Abstract
Flexion instability in posterior-stabilized total knee arthroplasty is a relatively uncommon but distinct problem that is often underdiagnosed and may require surgical management. This retrospective study evaluated the authors' management strategy and assessed the results of revision surgery. The authors identified 19 knees that underwent revision for isolated flexion instability after primary posterior-stabilized total knee arthroplasty. All patients had typical symptoms and signs of flexion instability, which include diffuse pain, especially when negotiating stairs, a sense of instability without giving way, recurrent joint effusions, and diffuse periarticular tenderness. Knee Society scores were used to assess pain and function. Complete revision was performed in 11 knees, femoral revision with a thicker insert was performed in 1 knee, and isolated tibial polyethylene insert exchange was performed in 7 knees. Postoperatively, all patients reported improvement in instability symptoms and signs associated with improvement in mean Knee Society scores. Revision surgery with careful gap balancing is successful in the management of isolated flexion instability in posterior-stabilized total knee arthroplasty. Isolated tibial polyethylene insert exchange may have a role in selected patients where component malalignment and malrotation is ruled out and a thicker and/ or semiconstrained insert can be used, while limiting the resultant flexion contracture to less than 5 degrees.
Volume Number
37
Issue Number
9
Pages
7
Document Type
Article
Status
Faculty
Facility
School of Medicine
Primary Department
Orthopedic Surgery
PMID
DOI
10.3928/01477447-20140825-52