Chapter 5 Special considerations in revision

m

•of aseptic loose total knee ' arthroplasty

The results of total knee, replacement revision are not as good as those of primary total knee replacement, the former being approximately 70% in the good to excellent range whereas the latter is approximately 90% (2).

Outcomes arc better for patients who undergo revision for aseptic loosening as opposed to infection. It is critical to identify the cause of the original prosthesis failure to improve the outcome following revision surgery (2).

As a general principle, revision surgeryshoul(Tr5ep^ffoTnreti™as"Soon as failure is diagnosed. A more satisfactory revision operation is obtained by early intervention (93).

1-Exposure :

Adequate skin coverage serves as a barrier to infection and must be sufficiently supple to allow knee motion (87).

/\nalysis of the vascular anatomy about the knee suggests that a midiine skin incision is less disruptive to the arterial network. Transcutaujous oxygen measurements made before and after incisions'of the skin about the knee have demonstrated reduced oxygenation of the lateral skin region (87).

Placement of the skin incision slightly lateral to the midline will assist in aversion of the patella, particularly in obese patients in whom a large and bulky lateral skin flap resists patellar eversion (88).