A Randomized Double-Blind Prospective Study Comparing the Efficacy of Subperiosteal and Periarticular Injections of a Local Anesthetic for Postoperative Pain Management after Total Knee Arthroplasty.

Objectives: Total knee arthroplasty (TKA) serves as an effective surgical treatment method for advanced osteoarthritis (OA). Nonetheless, it is associated with postoperative pain that can influence patients' functional outcome. This study aimed to compare the analgesic effect of subperiosteal and periarticular injection methods of a special local anesthetic in patients who underwent TKA. Methods: This double-blind prospective clinical study was conducted on patients with advanced knee OA who underwent TKA. Patients were randomly divided into two groups, with a local anesthetic (21 ml) administered either in periarticular (P group) or subperiosteal (S group) forms prior to wound closure. The local anesthetic consisted of lidocaine 2% (15 cc), dexmedetomidine (1 cc), and marcaine 0.5% (5 cc). A study-blinded orthopedic resident recorded postoperative pain levels using a 10-point visual analogue score (VAS) (0 indicating no pain, 10 indicating worst pain) at 6, 12, 24, and 48 hours after surgery. Results: A total of 40 patients (P and S group; n=20 each), consisting of 10 males (mean age=67.4 years old), were included in this study. The intensity of pain in the S group was significantly lower than in the P group 24 hours after surgery (mean VAS scores in the P group: 4±1 vs. the S group: 3.3±0.7, P=0.024). Furthermore, VAS scores at 6, 12, and 48 hours post-surgery were lower in the S group compared to the P group; however, the difference was not statistically significant (P>0.05). Conclusion: Our study indicated that subperiosteal injection of lidocaine, dexmedetomidine, and marcaine is more effective than periarticular injection, providing effective postoperative pain management after TKA.