Shoulder EA 2020

Inspired by Guan et al 2020,[1] and Dunning et al 2020.[2]

MC’s favourite EA protocol for chronic shoulder pain (left), best position for the elbows to avoid RC impingement when doing press-ups or holding this mid-press position (lower right)…

EA – electroacupuncture; a technique where electrical pulses are passed between pairs of filiform acupuncture needles placed in deep somatic tissues at locations usually defined as acupuncture points (APs).

EDN – electrical dry needling; a technique where electrical pulses are passed between pairs of filiform acupuncture needles placed in deep somatic tissues at locations usually defined by points in muscle targets that often bear a striking resemblance to APs.

This week I am highlighting two recent trials using EA or EDN in shoulder conditions. One is from China (n=54), based at a single centre 266km south west of Beijing called Shijiazhuang. The second is a US/Spanish collaboration (n=145) and based at 14 physical therapy clinics across 12 American states. The similarity is that they both utilised electrical stimulation of deep somatic tissue via filiform acupuncture needles in shoulder conditions.


SF – synovial fluid

IL – interleukin

MMP – matrix metalloproteinase

ASES – American Shoulder and Elbow Surgeons score

CMs – Contant-Murley score

SPADI – shoulder pain and disability index

VAS – visual analogue score vs NRS – numerical rating scale

RC – rotator cuff

SAP – subacromial pain

TM – thrust manipulation vs NTM – non-thrust mobilisation

TMEDN – thrust manipulation plus electrical dry needling

NTMEX – non thrust mobilisation plus exercise plus interferential

key to acronyms

The paper from Shijiazhuang is novel because it measured biomarkers in synovial fluid (SF) at three time points (baseline, 6 weeks and 6 months) and correlated these with symptomatic and functional changes. The patient group had MRI diagnosis of full thickness rotator cuff (RC) tears who were treated conservatively and had 6 months follow up. One group received standard rehabilitation for RC tears and the other received additional EA treatment: 12 sessions over 6 weeks to 4 points (LI15–SI9, jianqian–ST38), 200us pulses at 10Hz for 30 minutes and at an intensity sufficient to cause muscle twitch. Outcomes were two functional scores (ASES & CMs), VAS pain and SF biomarkers (IL–1b, IL–6, MMP–1, MMP–13).

IL–1b correlated strongly with functional scores pain

IL–1b correlated strongly with both functional scores (r=-0.59 & -0.73) and VAS pain (r=0.81). IL–6 correlated with VAS (r=0.7) and one of the functional scores (r=-0.67). MMP–1 correlated with one of the functional scores (r=-0.57), and MMP–13 did not correlate with any of the outcomes, but it was significantly lower in the EA group at both 6 weeks and 6 months, as were all the other biomarkers.

The second paper is a comparative trial of 2 different combinations of treatments in management of subacromial pain (SAP). Spinal thrust manipulation (cervicothoracic) was combined with 20 minutes of EDN: 4 pairs of local/regional needles stimulated at 2Hz with 250us pulses at a moderate intensity (TMEDN group). The comparator group received a more standard, gentle physical therapy approach with mobilisation, exercise and interferential (NTMEX group). The treatment schedule was the same as the first paper with 12 sessions over six weeks, and outcomes were a standard scale (SPADI) and NRS pain.

The TMEDN group was superior to the NTMEX group in both outcomes at all time points beyond baseline (2 weeks, 4 weeks and 3 months).

Are objective outcomes influenced by blinding?

So, we have a couple of quite convincing trials in favour of EA from a pragmatic perspective. Unfortunately both suffered methodically from a lack of blinding, that is why I have a marginal preference for the one from China, since objective outcomes (ie SF biomarkers) do not appear to be influenced by a lack of blinding (see previous blog: Blinding – where is the bias?).

Reference list

1         Guan J, Geng W-Q, Li Y, et al. Decreased Synovial Fluid Biomarkers Levels Are Associated with Rehabilitation of Function and Pain in Rotator Cuff Tear Patients Following Electroacupuncture Therapy. Med Sci Monit 2020;26:e923240. doi:10.12659/MSM.923240

2         Dunning J, Butts R, Fernández-de-las-Peñas C, et al. Spinal Manipulation and Electrical Dry Needling in Patients With Subacromial Pain Syndrome: A Multicenter Randomized Clinical Trial. J Orthop Sport Phys Ther 2020;:1–46. doi:10.2519/jospt.2021.9785

Declaration of interests MC