Post-TJR drug protocol reduces postop pain

Five weeks after surgery, only 6% of TKA patients reported finding recovery ‘very difficult.’

CHICAGO — Employing a multimodal pain control protocol after total hip or knee arthroplasty can significantly improve early postoperative recovery, according to a surgeon speaking here.

“It is our belief that the biggest advancement, which will remain over several years, is not mini-incision surgery, but managing the postop pain ... . And this would be done by local pain control, by patient education, appropriate physical therapy and reduced tissue trauma surgery,” said Chitranjan S. Ranawat, MD, of Lenox Hill Hospital in New York.

Ranawat and colleagues conducted two separate studies on total knee arthroplasty (TKA) and total hip arthroplasty (THA) patients using an established pain control protocol blinded to patients. He presented the results here at the American Academy of Orthopaedic Surgeons 73rd Annual Meeting.

TKA study

The TKA study group included 52 knees of 36 patients. Eleven patients (22 knees) underwent simultaneous bilateral TKA, 12 patients (17 knees) underwent staged bilateral TKA and 13 patients (13 knees) underwent unilateral TKA, Ranawat said. Perioperatively, all patients received Vioxx (rofecoxib, Merck & Co.), oxycodone and Coumadin (warfarin sodium, Bristol-Myers Squibb). Surgeons also offered patient-controlled analgesia (PCA) to all patients and gave most oral narcotics.

During the procedure, Ranawat also injected a local proprietary pain modifying mixture into all tissue trauma locations. The mixture, which Ranawat named the “BIG (MAC)²,” included the following:

40 mg to 120 mg of Marcaine (bupivacaine HCl, AstraZeneca);
4 mg to 6 mg of morphine;
300 µcg of adrenaline (epinephrine);
750 mg of Zinacef antibiotic (cefuroxime, GlaxoSmithKline);
40 mg of Depo-Medrol corticosteroid (methylprednosolone acetate, Pfizer Inc.); and
100 µcg of clonidine (Catapres, Boehringer Ingelheim Pharm. Inc.).

TKA pain results

Ranawat and colleagues found that 35% of patients did not require any PCA.

At five weeks all simultaneous bilateral TKA patients, 82% of staged bilateral TKA patients and 85% of unilateral TKA patients could perform straight leg raises. Additionally, at five weeks 82% of simultaneous bilateral, 88% of staged bilateral and 46% of unilateral patients could ambulate unassisted.

The researchers also found that 86% of simultaneous bilateral patients, 71% of staged bilateral patients and 69% of unilateral patients achieved 110° range of motion. And all patients could climb stairs without using a banister for assistance.

In the simultaneous bilateral TKA group, 64% of patients reported an easier recovery than expected compared with 82% of staged bilateral patients and 85% of unilateral patients, Ranawat said.

Overall, only 6% of patients described recovery as “very difficult,” he noted.

No patients developed infections, required manipulation, re-operation or had prolonged recovery. Additionally, the researchers found significant reductions in narcotic side effects, such as nausea, vomiting, cosmetic deficiency, urinary retention, respiratory depression, itching and rash.

“The BIG (MAC)² is promising in this small, retrospective, single-surgeon series,” Ranawat said. “It has proven to be safe and has significantly improved the recovery of knee function after total knee replacement in the early postop period.”

THA results

Ranawat and colleagues found similarly promising results using the same pain protocol in 40 hips of 35 THA patients. At six weeks, 60% of patients reported no pain, 37% reported mild pain and only 3% reported moderate pain. At three months, 94% reported no pain, while 3% reported mild and 3% reported moderate, Ranawat said.

Also at six weeks, 60% of patients did not limp, 70% could walk unlimited distances (1 to 2 miles) without a cane and 74% reported experiencing an easier recovery than expected, he said. These results improved at three months to 85% of patients being limp-free and 85% walking unlimited distances.

“It appears that controlling the pain after total joint surgery is the most important variable for early recovery of function ...,” Ranawat said.

These results prompted further ongoing IRB-approved, prospective randomized trial of 83 patients. Preliminary results show that THA and TKA patients receiving the pain control injection reported significantly less pain than patients receiving PCA, he noted.

For more information:
Ranawat H, Ranawat CS, Ranawat A, et al. Modifying the pain response after THR using local periarticular injections. #387. Presented at the American Academy of Orthopaedic Surgeons 73rd Annual Meeting. March 22-26, 2006. Chicago.