Calcific Tendinitis — Sudden Severe Shoulder Pain
Table of Contents
What is calcific tendinitis
Calcific tendinitis is a condition in which calcium crystals (hydroxyapatite) deposit within the rotator cuff tendons, especially the supraspinatus tendon. It is most common in those aged 30–50 and is slightly more frequent in women. While calcium is being formed, the patient may be asymptomatic, but during the resorption process a sudden, intense inflammatory reaction develops, causing severe acute shoulder pain. The pain is so extreme that many patients visit the emergency department.
Stages of calcium deposition
- Formative phase: Tendon cells transform into cartilage cells and calcium gradually deposits. Pain is mild or absent at this stage.
- Resting phase: The calcium has hardened and is in a stable state, with mild pain or some restriction of motion.
- Resorptive phase: Macrophages absorb the calcium, accompanied by neovascularization and acute inflammation. The area around the calcium swells and irritates the subacromial bursa, producing severe pain.
Korean medicine treatment strategy
Korean medicine treatment proceeds along two axes: controlling acute inflammation and accelerating calcium resorption.
- Acupuncture: In the acute phase, distal point selection (遠位取穴) is used, with needling at points such as Tiaokou (ST38) and Chengshan (BL57) to relieve pain without directly stimulating the shoulder. Once the acute phase passes, local shoulder points are needled directly.
- Pharmacopuncture: Anti-inflammatory pharmacopuncture and bee venom are administered adjacent to the calcium deposit to increase local blood flow and promote macrophage-mediated calcium resorption.
- Herbal medicine: In the acute inflammatory phase, formulas combining heat-clearing/toxin-resolving (清熱解毒) and blood-moving/stasis-resolving (活血祛瘀) actions are used. Herbs that drain dampness (利水滲濕) such as Coix seed (薏苡仁, uiyiin) and Alisma (澤瀉, taeksa) help with calcium absorption.
- Electroacupuncture: Low-frequency stimulation at 2 Hz has been reported to increase local blood flow and aid calcium resorption.
Course and prognosis
Calcific tendinitis is largely a self-limiting condition in which calcium is naturally absorbed and the patient improves over time. However, active Korean medicine treatment is recommended to minimize the severe pain and dysfunction during resorption and to accelerate the absorption process. Acute pain typically eases significantly within 1–2 weeks, and full recovery takes 2–3 months.