Effects of Traditional Cupping Therapy in Patients With Carpal Tunnel Syndrome: A Randomized Controlled Trial

Carpal tunnel syndrome is a fairly common condition that affects approximately 3% of the general population, causing numbness, tingling, burning, and pain especially in the thumb, index, and middle fingers. In addition to considerable physical discomfort, this syndrome can lead to work absenteeism and generate significant medical costs. Women are more frequently affected than men, and symptoms tend to be disabling for daily activities. The condition results from compression of the median nerve at the wrist, generally caused by fibrosis of connective tissue surrounding the flexor tendons.

Although there are conventional treatments such as splints, anti-inflammatory medications, and surgery, results are not always entirely satisfactory, with surgery yielding good results in only 75% of cases.

This study investigated the efficacy of a traditional therapy called wet cupping in the treatment of carpal tunnel syndrome. The research was conducted as a randomized controlled clinical trial with 52 outpatients who had a confirmed neurological diagnosis of the syndrome. Participants, with a mean age of approximately 58 years, were randomly divided into two groups: one received wet cupping therapy and the other received local heat application as a control. Cupping therapy consisted of superficially perforating the skin over the trapezius muscle in the shoulder region, applying suction cups for 5 to 10 minutes until they partially filled with capillary blood, performed in only one session.

The control group received heat application for 15 minutes at the same region. All patients were assessed at baseline and one week after treatment.

Results demonstrated significant benefits of cupping therapy compared with heat application. The total symptom score, which included pain, tingling, and numbness measured on visual analog scales, reduced dramatically in the cupping group: from 61.5 points to 24.6 points after seven days, while in the control group the reduction was smaller, from 67.1 to 51.7 points. This difference represents an improvement of approximately 60% in symptoms in the cupping-treated group. In addition, researchers observed significant improvements in functional disability, physical quality of life, and reduction of neck pain, which was present in most patients.

All participants completed the study without dropouts, and the treatment was considered safe and well tolerated, with only mild local hematomas as minor adverse effects.

For patients with carpal tunnel syndrome, these results suggest that cupping therapy may be a promising therapeutic option, especially considering that it is a simple treatment, performed in a single session, and provided substantial symptom relief. For healthcare professionals, the study indicates that complementary therapies based on traditional medicine may have a place in the therapeutic arsenal for this common condition. The theory behind the treatment is based on the "double crush" hypothesis, which suggests that problems in the cervical region and shoulder may contribute to wrist symptoms, and that treating these related areas may benefit the primary condition. Cupping therapy may work by improving local circulation, modulating lymphatic flow, and exerting antinociceptive effects.

The study has some important limitations that should be considered when interpreting the results. As an open-label study, where neither patients nor researchers were blinded to the treatment received, there is the possibility that placebo effects influenced the results. Although researchers assessed patient expectations and found no significant differences between groups, developing a convincing placebo procedure for cupping therapy remains challenging. In addition, follow-up was limited to only one week, not allowing assessment of long-term effects.

The sample size, although adequate to detect significant differences, was relatively small. Future studies with longer follow-up periods, control groups with established treatments for carpal tunnel syndrome, and if possible with masking procedures, will be necessary to confirm these promising results and establish the role of cupping therapy in the treatment of this prevalent condition.