Failure to balance the soft tissues among top 10 reasons for early revision after TKA

While total knee arthroplasty remains a reliable procedure, most failures are the result of surgeon errors, according to a new report.

At the 9th Annual Current Concepts in Joint Replacement Spring Meeting, John M. Cuckler, MD, listed the top 10 reasons that patients undergo revision within 2 years of total knee arthroplasty (TKA).

The best way to ruin a good total knee arthroplasty is operating on patients too soon, he said. Surgeons may perform TKA without trying conservative treatments and surgical alternatives.

"Don't operate too early or you may have an unhappy patient," Cuckler said.

Revisions may also result from surgeons failing to balance the soft tissues. Surgeons should produce collateral ligament tension in both 0° of extension and 90° of flexion.

"If you choose to do a cruciate-retaining knee, you need to make sure that the posterior structures, primarily the PCL, are not too tight in extension," Cuckler said.

While new implant designs help surgeons avoid patellar tilt and dislocation, patella maltracking is still an issue. If subluxation is noted, Cuckler recommends checking the component rotation first and then evaluating the need for a lateral retinacular release.

Procedures can also be ruined by failing to restore the neutral mechanical axis of the knee, he said. Tibial component malpositioning can also lead to failure.

He cited infection as another leading cause of revision, and internal rotation of the femoral component can also result in suboptimal outcomes.

"Component malposition is a major source of failure of MIS (minimally invasive surgery) technique, and this usually results from an asymmetric flexion gap, which is going to result in patellar maltracking and flexion instability," Cuckler said.

He warned that prolonged observation of wound drainage could lead to infection and a marred TKA.

"I don't believe that you should observe draining incisions more than 48 hours," Cuckler said. "If you see bloody drainage, it is a sign of a deep hematoma. It needs to be drained in the operating room."

Wound complications stemming from a failure to respect prior incisions, raising large subcutaneous flaps or delaying closure can result in infection and, ultimately, failure. Likewise, knee pain with secondary gain can also result in an unsuccessful TKA, he said.

For more information:
John M. Cuckler, MD, can be reached at Brookwood Medical Plaza, 513 Brookwood Blvd., Suite 375, Homewood, AL 35209; 205-802-4577; e-mail: Jcuckler@charter.net. He holds intellectual property rights with Biomet.

Reference:
Cuckler JM. Top 10 ways to ruin a perfectly good TKA. Paper #37. Presented at the 9th Annual Current Concepts in Joint Replacement Spring Meeting. May 18-21, 2008. Las Vegas.