Does adding corticosteroids to periarticular injection affect the postoperative acute phase response after total knee arthroplasty?

Periarticular injection (PAI) can reduce pain and improve early outcomes following total knee arthroplasty (TKA). Although corticosteroid PAI has been reported to be safe and effective, investigations on the postoperative acute phase response (APR) are scarce.

This retrospective cohort study with propensity score matching investigated two groups of patients after TKA: the steroid group (n = 50) received an intraoperative corticosteroid PAI (methylprednisolone 40 mg); the non-steroid group (n = 50) did not receive the corticosteroid. To evaluate the APR, C-reactive protein (CRP) levels and erythrocyte sedimentation rates (ESR) were determined preoperatively and on postoperative day (POD) 2, 4, 6, 14, and 28. A visual analogue scale (VAS) was used to measure pain on the night of surgery and on POD 1, 2, 4, and 6. Maximal flexion at discharge (POD 7), morphine equivalent dose (MED), and complications were also evaluated.

The steroid group showed significantly lower CRP levels on POD 2 ( P < .05) and POD 4 ( P < .05) but a higher CRP level on POD 6 ( P < .05). However, ESR levels did not differ between the two groups in all measurements. Peak values in CRP and ESR in the steroid group (POD 4 and 6) appeared two days later compared with the non-steroid group (POD 2 and 4). The VAS pain score was significantly lower in the steroid group on POD 2 ( P < .05). Maximal flexion on discharge, MED and complication rate were similar in the two groups.

Adding a corticosteroid to the PAI following TKA attenuated the APR, and also provided significant pain relief.