Pain control, management expected to be next great TKA advance, leading surgeon says

Pain causes some 15% of TKA patients to have trouble reaching proper knee function. New drug regimens may help to drastically reduce that number.

ORLANDO, Fla. — Applying an innovative pain control regimen helped a New York orthopedic surgeon greatly reduce the number of total knee arthroplasty patients with difficulty obtaining proper postop knee function.

"The biggest improvement in patient care in 25 years has been pain control after hip and knee surgery and the impact of that on recovery of function," said Chitranjan S. Ranawat, MD, here at the Current Concepts in Joint Replacement Winter 2006 meeting. "The next great advance will be perioperative pain management," added Ranawat, who is chairman of orthopedics at Lenox Hill Hospital in New York City.

Earlier studies show that while over 85% of total knee arthroplasty (TKA) patients recover full knee function regardless of the rehabilitation protocol used, the remaining 15% have difficulty reaching full function because of significant pain. Yet, only about one in five of those struggling patients actually need postop manipulation, Ranawat said. In other words, the pain was stalling motion recovery, he said.

"It appears that controlling pain is a more important variable than the length of an incision" when it comes to the quality of TKA outcomes, Ranawat said.

Using an alternate pain management regimen, Ranawat and colleagues found in a retrospective study that no patients required prolonged physical therapy or manipulation to reach good function.

That study reviewed 60 TKA patients (67 knees) from Ranawat's center who received an advanced pain management protocol, as follows: Starting on day 1, rofecoxib 50 mg (Vioxx, Merck & Co.); oxycodone 20 mg (OxyContin, Purdue Pharma L.P.); and warfarin 5 mg (Coumadin, Bristol-Myers Squibb). All patients also received spinal anesthesia.

Ranawat's team administered the following local mixture of drugs intraoperatively for pain management: a local mixture of bupivacaine 80 mg; methylprednisolone 40 mg (Depo-Medrol, Pfizer); morphine 4 mg; epinephrine 300 mg; and cefuroxime 75 mg (Zinacef, GlaxoSmithKline) injected into specific ligaments, tendons and other areas. Some patients also received additional corticosteroid intravenously. Patients received Vioxx, PCA Percodan (oxycodone/aspirin, Endo Pharmaceuticals) and acetaminophen as standing orders postop.

In his abstract, Ranawat also noted that, "A relationship appears to exist between acute postoperative pain and the development of arthrofibrosis. By controlling acute pain in the critical early postoperative period following TKR (ie, 3 days), the presented pain management protocol allowed for improved recovery of knee function with no manipulation or prolonged rehabilitation."

For more information:
Ranawat CS. Optimizing postop performance: Be all you can be. #87. Presented at the 23rd Annual Current Concepts in Joint Replacement Winter 2006 Meeting. Dec. 13-16, 2006. Orlando, Fla.