EA for AOA

Inspired by Jiang et al 2025.[1]

EA – electroacupuncture
AOA – ankle osteoarthrosis
IF – impact factor
AOS – Ankle Osteoarthritis Scale
AOFAS-AHS – American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale
MCID – minimal clinically important difference
NSAIDs – non-steroidal anti-inflammatory drugs
US – ultrasound
PRP – platelet rich plasma

– key to acronyms

This paper is from the journal Back and Musculoskeletal Rehabilitation (IF 1.4) – a journal published by Sage. It was started in the early 1990s and focusses on an interdisciplinary approach to musculoskeletal rehabilitation.

This is the first RCT I have seen specifically in AOA (n=78), whether involving acupuncture or any other treatment. I have only treated a handful of patients for chronic ankle pain that was labelled as AOA. I recall struggling to find points close to the joint that I could use for EA. In general, we like to apply EA to deep somatic tissues, otherwise we might as well use TENS applied to the surface of the skin.

I used to slide needles under the skin in front of the malleoli and use points in front of the Achilles but was never very satisfied by the points over the anterior joint line of the ankle mortice. I would also pair up SP6 to LR3. This was until Hugo used me as a model for his ankle rehabilitation protocol on the BMAS Boat Trip up the Douro in 2013.

He buried a needle at GB40, almost 40mm deep into my sinus tarsi. I assumed he had placed it into my ankle joint, but on closer inspection of the anatomy I saw that this point goes between two talocalcaneal joints. Subsequently, I started using this as my favourite ankle point, together with a point just in front of the fibular at the level of GB39, which is approximately the same level as SP6. I have stopped using LR3 for EA in most circumstances because of the proximity of a large peripheral nerve – the deep fibular (peroneal) nerve. So, now I pair SP6 with a point just below the talonavicular joint in the muscle of the medial arch. This point is just behind KI2.

The main points used in this paper were ST41, KI3, BL60, ST36, GB34. Then additional points were added based on the location of pain: GB40, GB39, BL62, and GB41 for the lateral side; KI6, KI2, SP5, and SP6 for the medial side. EA pairs were connected as follows: ST36 to GB34; KI3 to ST41 (medial pain); BL60 to GB40 (lateral pain).

The image in the paper has the EA connected to the medial and lateral pairs, but not to ST36 and GB34.

EA was applied at 100Hz for 30 minutes daily (5 days a week) for 4 weeks. The control group performed resistance training in 4 directions using elastic bands. Positions were held for 10 seconds with 3 seconds of rest. 10 reps in each direction were performed daily, 5 days a week for 4 weeks. The EA group also performed these exercises.

The primary outcomes in this trial were the AOS and the AOFAS-AHS. Both scales are reported from 0 to 100, but the AOS score goes down and the AOFAS-AHS score goes up with improvement in the condition. Three-dimensional gait analysis was performed as a secondary outcome measure.

Since EA was added as an additional treatment to one group, it is not surprising that this group was better than the control after 20 sessions (4 weeks). The improvement from baseline in the AOS score was ~57 in the EA group and ~30 in the exercise only group. Both of these exceeded the MCID for the measure, which has been reported as 28.[2]

The AOFAS-AHS score improved by ~22 in the EA group and ~7 in the exercise only group. The MCID for this outcome is 12, and the final score in the EA group reached near-normal function, having started in the range of moderate impairment.

Gait analysis showed up one or two significant differences between groups and several more significant improvements within each group.

I decided to ask ChatGPT if he, she, they, or it, knew of any conventional arthritis treatments that had been tested in AOA specifically. I got back a summary with a list of 10 interventions, starting with NSAIDs and corticosteroid injections, moving through surgery, and ending with stem cell therapy. I asked for the references supporting the use of NSAIDs, and it turned out there were none in AOA, but ChatGPT had done what the rest of the medical world does with drugs and extrapolated from studies in other joints.

I called out the oversight, and when pushed into a corner, ChatGPT admitted that ‘there is a notable gap in RCTs specifically assessing their [NSAIDs] efficacy in this condition [AOA]’.

So, I opted to go back to the old school method of searching myself on PubMed. I only found 5 papers that came up with a search for ‘ankle osteoarthritis [ti]’ and limited to RCTs.

One was a feasibility study on education and exercise, and no data on efficacy.[3] One was a surgical study where an intraoperative injection with a multidrug concoction proved superior to no injection in terms of immediate post-operative use of analgesics.[4] A third paper compared sodium hyaluronate with saline injections in just 20 patients enrolled from 128 potential subjects.[5] I cannot get the full text, but with just 20 included and 17 finishing, I don’t think it is really worth looking.

Finally, the two best papers describe the initial results and long-term follow-up data of a trial of US guided injection of PRP versus saline (n=100).[6,7] There was no difference between groups, and neither group breeched any MCIDs from baseline, although the saline group almost made it.

References

1          Jiang C, Xia L, Li H, et al. Effect of electroacupuncture for early ankle osteoarthritis: A randomized controlled trial using three-dimensional gait analysis. J Back Musculoskelet Rehabil. 2025;10538127241308216. doi: 10.1177/10538127241308216

2          Coe MP, Sutherland JM, Penner MJ, et al. Minimal clinically important difference and the effect of clinical variables on the ankle osteoarthritis scale in surgically treated end-stage ankle arthritis. J Bone Joint Surg Am. 2015;97:818–23. doi: 10.2106/JBJS.N.00147

3          Smith MD, Vuvan V, Collins NJ, et al. A combined program of education plus exercise versus general advice for ankle osteoarthritis: A feasibility randomised controlled trial. Musculoskelet Sci Pract. 2024;74:103169. doi: 10.1016/j.msksp.2024.103169

4          Kim YS, Kim BS, Koh YG, et al. Efficacy of multimodal drug injection after supramalleolar osteotomy for varus ankle osteoarthritis: A prospective randomized study. J Orthop Sci Off J. 2016;21:316–22. doi: 10.1016/j.jos.2016.02.002

5          Salk R, Chang T, D’Costa W, et al. Viscosupplementation (hyaluronans) in the treatment of ankle osteoarthritis. Clin Podiatr Med Surg. 2005;22:585–97, vii. doi: 10.1016/j.cpm.2005.07.007

6          Paget LDA, Reurink G, de Vos R-J, et al. Effect of Platelet-Rich Plasma Injections vs Placebo on Ankle Symptoms and Function in Patients With Ankle Osteoarthritis: A Randomized Clinical Trial. JAMA. 2021;326:1595–605. doi: 10.1001/jama.2021.16602

7          Paget LDA, Reurink G, de Vos R-J, et al. Platelet-Rich Plasma Injections for the Treatment of Ankle Osteoarthritis. Am J Sports Med. 2023;51:2625–34. doi: 10.1177/03635465231182438

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Declaration of interests MC