Randomized trial of trigger point acupuncture treatment for chronic shoulder pain: a preliminary study

There is evidence for the efficacy of acupuncture treatment for chronic shoulder pain, but it remains unclear which acupuncture modes are most effective. We compared the effect of trigger point acupuncture (TrP), with that of sham (SH) acupuncture treatments, on pain and shoulder function in patients with chronic shoulder pain. The participants were 18 patients (15 women, 3 men; aged 42-65 years) with nonradiating shoulder pain for at least 6 months and normal neurological findings. The participants were randomized into two groups, each receiving five treatment sessions. The TrP group received treatment at trigger points for the muscle, while the other group received SH acupuncture treatment on the same muscle. Outcome measures were pain intensity (visual analogue scale, VAS) and shoulder function (Constant-Murley Score: CMS). After treatment, pain intensity between pretreatment and 5 weeks after TrP decreased significantly (p<0.001). Shoulder function also increased significantly between pretreatment and 5 weeks after TrP (p<0.001). A comparison using the area under the outcome curves demonstrated a significant difference between groups (p=0.024). Compared with SH acupuncture therapy, TrP therapy appears more effective for chronic shoulder pain.