Effect of Electroacupuncture on the Treatment of Chronic Achilles Tendinopathy: A Case Report

EXTENDED ABSTRACT

Background

Chronic Achilles tendinopathy is a common musculoskeletal disorder in physically active and non-active populations and is typically characterized by pain, swelling, and impaired lower-limb function such as walking [1]. Although many patients improve with conservative management, including activity modification, heel elevation, physiotherapy modalities, eccentric exercise, and anti-inflammatory interventions, a subgroup continues to experience persistent symptoms, and treatment can remain challenging [2]. Electroacupuncture combines mechanical stimulation by solid filiform needles with local electrical stimulation and has been investigated as a minimally invasive approach for musculoskeletal disorders. Experimental and clinical reports have suggested potentially beneficial effects of electroacupuncture or related needling approaches on tendon healing and tendinopathy [3-6]. A previous report describing two patients with chronic Achilles tendinopathy also suggested clinically meaningful improvement after electroacupuncture [7]. Clinical management is also important because symptom resolution can be prolonged. The source article notes that improvement commonly occurs over three to twelve months, whereas chronic symptoms may persist for years in a proportion of patients, with consequences for physical activity and quality of life [2]. Electroacupuncture has been proposed as a complementary option in this difficult-to-treat subgroup, but clinical evidence remains limited, particularly for patients whose symptoms persist despite standard conservative procedures. The present case report therefore describes the electroacupuncture technique and clinical course of a patient with chronic Achilles tendinopathy that had not responded adequately to several prior treatments, with emphasis on pain, ankle range of motion, functional activities, treatment tolerability, and short-term persistence of the response.

Methods

A 53-year-old man was referred to Mobasher Kashani Physiotherapy Clinic in Hamadan in January 2024 with a six-month history of pain in the left Achilles tendon and limitations in daily activities. He reported pain during walking and running. Clinical assessment, including a positive resisted isometric test of the gastrosoleus muscle, was consistent with chronic Achilles tendinopathy. He had previously received corticosteroid injection, shock-wave therapy, and laser therapy without substantial improvement. Baseline pain intensity was 8/10 on a visual analogue scale. Active ankle dorsiflexion of the affected left ankle was 0 degrees, compared with 20 degrees on the healthy right side, indicating a 20-degree restriction. Plantar flexion was 45 degrees bilaterally. Because of pain and restricted motion, he was unable to run and could not tolerate prolonged walking. Electroacupuncture was delivered by a physiotherapist experienced in acupuncture using an SDZ-III electroacupuncture device. After skin sterilization, 3-mm needles were placed in the distal Achilles tendon and at BL60, BL61, KI3, and KI4, with needles inserted into the tendon as described in the source protocol [4]. Electrical stimulation was then applied as an alternating current at 5 Hz and 5 mA for 20 minutes. Treatment was performed three times weekly for a total of 10 sessions. Pain intensity, active ankle range of motion measured with a universal goniometer, and functional activities including walking and running were assessed at the first session, the tenth session, and again two months after treatment. The healthy contralateral ankle was used as a practical range-of-motion comparator. The intervention was intended as a focused local treatment; no concomitant therapeutic change was described during the electroacupuncture course, and the clinical response was evaluated against the patient's persistent six-month pre-treatment symptom history and previous lack of meaningful response to conservative modalities. Treatment-related adverse effects were also monitored throughout the intervention and follow-up.

Results

The patient showed clinically important improvement over the treatment period. After 10 electroacupuncture sessions, pain intensity decreased from 8/10 to 3/10. According to the tabulated range-of-motion findings, active dorsiflexion of the affected ankle improved from 0 degrees at the first session to 15 degrees at session 10, while the healthy ankle remained at 20 degrees. Two months after treatment, dorsiflexion of the affected ankle reached 20 degrees, matching the healthy side. Plantar flexion remained 45 degrees on both sides at all three assessment points. These changes are summarized in Table 1. Functionally, after 10 sessions the patient no longer reported limitation or disability during walking and gradually resumed running. At the two-month follow-up, he reported no pain and no limitation in daily activities or running, representing complete self-reported functional recovery. No adverse effects related to electroacupuncture were reported during the treatment course.

Table 1. Active ankle range of motion before and after electroacupuncture treatment.

Figure 1. Electroacupuncture needles inserted into the distal Achilles tendon and at BL60, BL61, KI3, and KI4.

The intervention itself was performed by inserting the needles into the distal Achilles tendon and the specified BL60, BL61, KI3, and KI4 points and connecting them to the electroacupuncture device, as illustrated in Figure 1. The source article interprets the observed response in the context of combined mechanical and electrical stimulation. Mechanical needling may create controlled local microtrauma, while electrical stimulation may augment local tissue responses. The discussion cites experimental work in tendon models describing increases in collagen fibril diameter, collagen synthesis and organization, cellular activity, and mechanical properties after acupuncture or electroacupuncture [3, 5, 6, 9]. The clinical response in this patient was also considered consistent with the earlier case report by Hawks [7]. Because this was a single uncontrolled case and no imaging such as musculoskeletal ultrasonography was available to document structural tendon healing, the findings demonstrate a temporal clinical association rather than proof of efficacy.

Conclusion

In this patient with six months of chronic Achilles tendinopathy that persisted despite corticosteroid injection, shock-wave therapy, and laser therapy, a 10-session course of electroacupuncture was associated with marked pain reduction, restoration of ankle dorsiflexion, return to walking and running, and maintenance of improvement at two months without reported adverse effects. The case supports electroacupuncture as a potential complementary option for selected patients with refractory chronic Achilles tendinopathy. Nevertheless, the evidence is limited by the single-patient design, absence of a control group, and lack of objective imaging assessment; controlled prospective clinical studies with adequate sample sizes and validated structural and functional outcome measures are required before the treatment effect can be generalized.

Keywords: Achilles Tendon, Electroacupuncture, Tendinopathy

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