No short term pain benefit of adding corticosteroids to periarticular analgesia after total knee arthroplasty: a prospective, double-blind, randomized controlled trial.

OBJECTIVES: This randomized controlled trial aimed to evaluate the short term effects of adding different doses of corticosteroids to periarticular infiltration analgesia (PIA) on pain control and functional recovery after total knee arthroplasty (TKA).

METHODS: A total of 234 patients undergoing TKA were randomly assigned to one of three groups: Group H (PIA with 21 mg betamethasone), Group N (PIA with 7 mg betamethasone), and Group C (PIA without corticosteroid). The PIA cocktail (80 mL) consisted of 300 mg of 0.75% ropivacaine, 5 mg morphine, 50 mg flurbiprofen, and 0.4 mL of 1:1000 epinephrine. The primary outcome was the Visual Analog Scale (VAS) score during active knee flexion. Secondary outcomes included resting VAS scores, active range of motion (AROM), 1-min walking distance, knee circumference (measured at three levels: 10 cm above the superior patellar pole, mid-patella, and 10 cm below the inferior patellar pole), total rescue analgesic consumption, serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and fasting blood glucose. Tertiary outcomes involved the incidence of postoperative adverse events.

RESULTS: No significant intergroup differences were observed in active flexion VAS scores at any postoperative time point. From postoperative days 1-4, A ROM was significantly greater in Groups H and N than in Group C. Group H also demonstrated significantly reduced mid-patella circumference and lower rescue analgesic consumption compared to the other groups. In addition, CRP and ESR levels were significantly lower in Group H. However, this group exhibited transiently elevated blood glucose at 6 h post-surgery. No significant differences were found among the three groups in other secondary outcomes, including resting VAS, 1-min walking distance, additional knee circumference measurements, and adverse event rates.

CONCLUSION: The adjunct use of corticosteroids in PIA did not enhance short-term pain control or ambulation capacity after TKA. Although corticosteroid supplementation reduced inflammation, improved early ROM, and decreased rescue analgesic requirements, it induced dose-related hyperglycemia. Therefore, high-dose steroid-containing PIA should be avoided in patients with diabetes or glucose intolerance.