|
Year |
2007 |
|---|---|
|
Question Number |
28 |
|
Category |
Hip and Knee Reconstruction |
Question
An obese 70-year-old woman with a history of diabetes mellitus and peripheral neuropathy underwent primary total knee arthroplasty 8 weeks ago. Postoperatively, she had reported knee instability that made walking difficult, and after a fall, she now reports increased pain. Radiographs are shown in Figures 8a and 8b. Treatment should consist of
1- closed reduction and casting.
2- tibial insert exchange.
3- conversion to a posterior stabilized femoral component.
4- revision to a constrained condylar component.
5- revision to a rotating hinge.
Figures
Answer (click for answer)
The answer is 5- revision to a rotating hinge.
All her knee ligaments are likely disrupted, as it would be hard to get an x-ray like the one in the figure with PCL, MCL, and LCL intact. Therefore she needs the constrain of a rotating hinge as she is very unstable in all planes of motion.
Reference: Sculco: role of constraint in TKA, J arthroplasty 2006; 21:54-6
Morgan: constraint in primary TKA, J Am Acad Orthop Surg, Vol 13, No 8, Dec 2005, 515-524.
