The Effectiveness of Cupping Therapy on Relieving Chronic Neck and Shoulder Pain: A Randomized Controlled Trial

Chronic neck and shoulder pain (CNSP) is a common musculoskeletal condition affecting 16% to 78% of the general population, especially prevalent in middle-aged and older adults. This condition can significantly impact quality of life, affecting social activities, future plans, and the emotional well-being of families. Cupping therapy, an ancient technique of traditional Chinese medicine recognized by the World Health Organization, has been used worldwide as a complementary treatment for various pain conditions. This single-blind randomized controlled trial investigated the immediate efficacy of cupping therapy in relieving CNSP, focusing on changes in skin surface temperature as a physiological indicator of therapeutic effects.

The research was conducted in Taiwan between October 2012 and February 2013, recruiting 60 participants through community advertisements. Inclusion criteria required participants to work at least 40 hours per week and to have suffered work-related pain continuously for at least 3 consecutive months, with a minimum intensity of 3 points on the visual analog scale (VAS). Individuals with infection, injury, or bleeding in the skin of the treatment area, cervical neuropathy, use of analgesics in the preceding 4 hours, or caffeine consumption in the same period were excluded. Participants were randomized into two groups of 30 each.

The cupping therapy group received fire cupping at three specific acupuncture points: SI-15 (Jianzhongshu), located in the back about 3-4 cm lateral to the lower edge of the spinous process of the seventh cervical vertebra; GB-21 (Jianjing), located at the midpoint between the dazhui point and the acromion of the shoulder; and LI-15 (Jianyu), located on the lateral aspect of the arm in the deltoid muscle. The procedure consisted of applying medium glass cups (4 cm in diameter, 260 mL volume) for 10 minutes on each side of the body, totaling 20 minutes of treatment. The control group rested for the same period. Measurements were performed using a FLIR ThermaCAM infrared camera for skin surface temperature, a mercury sphygmomanometer for blood pressure, and a visual analog scale for pain intensity.

Skin temperature was recorded at 5-minute intervals, while pain was assessed through specific neck movements (flexion, rotation, lateral bending) and shoulder movements (arm elevation, extension). The results demonstrated significant efficacy of cupping therapy. Skin surface temperature increased at all three acupuncture points in the cupping therapy group: SI-15 increased from 30.7°C to 32.8°C (an increase of 2.1°C); GB-21 from 30.6°C to 32.7°C (an increase of 2.1°C); and LI-15 from 29.4°C to 31.1°C (an increase of 1.7°C). The control group showed no significant changes in temperature.

As for pain, neck pain intensity decreased dramatically from 9.7 to 3.6 points in the cupping therapy group (a 6.1-point reduction), while in the control group it decreased only from 9.7 to 9.5 (a 0.2-point reduction). Shoulder pain also improved significantly, decreasing from 8.5 to 2.6 points in the treatment group (a 5.9-point reduction) versus 8.5 to 7.9 points in the control group (a 0.6-point reduction). All differences between groups were statistically significant (p < 0.001). Systolic blood pressure also decreased in the cupping therapy group, from 117.7 to 111.8 mmHg.

Mechanistically, cupping therapy promotes local vasodilation, increasing blood flow in the treated area. This effect results in hyperemia, a sensation of warmth, and accelerated elimination of toxins and metabolic waste, improving local physical function. The increase in skin temperature observed confirms these physiological effects and correlates with the pain relief reported by participants. The clinical implications are promising, suggesting that cupping therapy may be an effective and safe alternative to analgesics for chronic neck and shoulder pain.

The treatment was well tolerated, with only two participants reporting mild low back pain related to the seated position, and no other adverse effects. No participant developed localized burns or adverse reactions in the treated areas, confirming the safety of the procedure when performed appropriately. The limitations of the study include the relatively small sample size, female predominance (91.7% women), evaluation of only one treatment session without long-term follow-up, and the inability to fully blind because of the nature of the intervention. Future studies should investigate multiple sessions, larger samples with balanced sex and age distribution, and prolonged follow-up to assess the durability of effects.

This study contributes significantly to the scientific evidence on cupping therapy, providing objective data on its physiological and therapeutic effects and supporting its integration as a complementary therapy in the management of chronic musculoskeletal pain.