Comparison of intra-articular steroid injection and pericapsular nerve group block for pain control and functional outcomes in patients undergoing manipulation under anaesthesia for frozen shoulder – A randomised controlled trial

Background and Aims: Manipulation under anaesthesia (MUA) for frozen shoulder is usually done under intra-articular steroid injection along with local anaesthetic agents. The pericapsular nerve group (PENG) block is also found to be effective for MUA. This study aimed to compare the efficacy of the PENG block with that of intra-articular steroid injections in patients with frozen shoulder. Methods: This randomised controlled trial was conducted on 130 patients aged 18–75 years with stage 2 or stage 3 frozen shoulder scheduled for manipulation under anaesthesia. The participants were randomly assigned into two groups: Group S (intra-articular steroid injection) and Group P (PENG block). Group S received ultrasound-guided intra-articular injection of 40 mg triamcinolone with 2 mL of 2% lignocaine and 2 mL of 0.5% bupivacaine. Group P received ultrasound-guided PENG block using 10 mL of 0.5% bupivacaine and 10 mL of 2% lignocaine. Numerical pain rating scale (NPRS) scores for pain were recorded at 15 min; 30 min; and 1, 6, 12, and 24 hours. Range of Motion (ROM) and Shoulder Pain and Disability Index (SPADI) were also assessed. Data were analysed using Statistical Package for Social Sciences 19.0, and P < 0.05 was considered statistically significant. Results: NPRS pain scores were significantly lower in the PENG group across all time points ( P < 0.001). At 15 minutes, the mean NRPS scores were 5.2 [95% confidence interval (CI) 4.8–5.6] in Group S and 4.1 (95% CI 3.5–4.7) in Group P. ROM and SPADI scores at 24 hours were significantly better in the PENG group. ROM improved across all planes in both groups; however, improvement was significantly greater in the PENG block group. Conclusion: PENG block is effective in providing pain relief and improving shoulder function following MUA in patients with frozen shoulder.