Corticosteroids are commonly used in total knee arthroplasty (TKA) to reduce pain and prevent nausea. But are the effects of steroids different when administered locally rather than systemically? Hatayama et al. investigate this question in JBJS, where they report on a randomized controlled trial comparing periarticular injection with intravenous (IV) administration of corticosteroids. The authors assessed the drugs’ effects on pain control, the prevention of postoperative nausea, and inflammation and thromboembolism markers following TKA.
The 100 included patients were 50 to 85 years of age and underwent primary, unilateral TKA for osteoarthritis. Fifty patients were randomized to the intravenous group (10 mg dexamethasone IV 1 hour pre- and 24 hours postoperatively, along with periarticular placebo injection during the procedure), and 50 were randomized to the periarticular injection group (a 40-mg injection of triamcinolone acetonide during surgery, along with IV placebo 1 hour pre- and 24 hours postoperatively).
Patients in the periarticular injection group experienced better pain control at 24 hours postoperatively, both at rest and during walking. The antiemetic effect was similar and notable in both groups. The IV group showed a better anti-thromboembolic effect, as measured by prothrombin fragment 1.2 levels, but the incidence of deep venous thrombosis was low overall, each group having only 2 cases.
The authors also reported that, at 24 and 48 hours, interleukin-6 levels did not differ between the groups, while C-reactive protein (CRP) levels were significantly lower in the IV group. In contrast, 1 week after surgery, patients in the periarticular group had a significantly lower CRP. These inflammatory-marker findings lead Hatayama et al. to postulate that “the better [24-hour] pain control in the periarticular injection group was not because of reduced inflammation,” and they note that locally administered corticosteroids directly inhibit signal transmission in nociceptive fibers.