To compare the pain and functional improvement of suprascapular nerve block (SSNB) and intra-articular hyaluronic acid (HA) injection in post-stroke patients with hemiplegic shoulder pain.

In total, 24 stroke patients were randomly assigned in the SSNB group (n = 12) or the HA group (n = 12). Ultrasound (US) guided SSNB with 10 cc of 1% lidocaine and US guided intra-articular injection with 2 cc of HA was done in each group 3 times weekly. Visual analogue scale (VAS), Fugl-Meyer scale (FMS), Wolf motor function test (WMFT), Brunnstrom stage, modified Ashworth scale (MAS), range of motion (ROM) of shoulder joint and brief pain inventory (BPI) concerning the interference of patient's function (activity, mood, walking, work, relationship, sleep and enjoy) were assessed before the injection, one week and four weeks after first injection.

Both groups showed significant improvements in pain assessed by VAS, but the changes between the two groups were not significantly different. There were no significant improvements and did not show any significant differences between the two groups in FMS, WMFT, Brunnstrom stage, MAS and ROM of shoulder joint. On several items of the BPI concerning the interference of patient's function (activity, mood, work, and enjoy), only SSNB group showed significant improvement, even though the differences between the two groups were not significant.

Both SSNB and intra-articular HA injection were safe and effective in pain and functional ability in hemiplegic shoulder pain. But comparing the interference of patient's function caused by pain, only SSNB showed significant improvement.