(HealthDay News) — In patients with myofascial pain syndrome (MPS), trigger point injection (TPI) with lidocaine and hyaluronidase works more quickly on the first day following injection than lidocaine alone, but there are no significant differences between the methods after 4 days, according to a study published online Oct. 7 in Pain Practice.
Ji Won Choi, MD, from the Sungkyunkwan University School of Medicine in Seoul, South Korea, and colleagues randomized 61 adults (aged 25–75 years) with MPS affecting both trapezius muscles to treatment with either lidocaine (31 patients; 3.2mL 0.5%) or hyaluronidase (30 patients; 3.2mL 0.5% lidocaine + hyaluronidase 600 IU/mL). All patients received TPI. The verbal numerical rating scale (VNRS), the neck disability index (NDI), and the short form of brief pain inventory (BPI-SF) were used to evaluate outcomes.
The researchers found that in both groups, VNRS decreased on Days 4, 7, and 14, compared to pre-TPI. In the lidocaine + hyaluronidase group, there was also a decrease in VNRS on Day 1. However, there were no significant VNRS differences between the groups. Both groups experienced significant decreases in NDI and BPI-SF scores after TPI.
“TPI consisting of lidocaine mixed with hyaluronidase worked more effectively than lidocaine alone on post-TPI day one,” the authors write.