Effectiveness of Acupuncture Therapies to Manage Musculoskeletal Disorders of the Extremities: A Systematic Review

Musculoskeletal disorders of the extremities (arms and legs) are a significant public health concern. In the United States, injuries such as sprains and strains account for a considerable portion of emergency department visits — 16% of all upper-extremity injuries and 36% of lower-extremity injuries. In Brazil, many people seek acupuncture as treatment for these problems, but until recently there was little solid scientific knowledge about its actual efficacy. Researchers therefore conducted a rigorous systematic review to evaluate whether different types of acupuncture really help people with musculoskeletal disorders of the arms and legs.

To answer this question, the researchers performed a comprehensive search across five large scientific databases, looking for studies published between 1990 and 2015. They included only randomized controlled trials — the type of study considered the gold standard in medicine — that tested different forms of acupuncture. Studies had to include at least 30 participants per treatment group to have adequate statistical power. The team critically analyzed the methodological quality of each study using rigorous criteria, classifying them as low or high risk of bias.

Only high-quality studies were used to formulate the main conclusions.

Of the 5,180 publications initially identified, only 15 studies met the inclusion criteria, with 10 of them classified as of high methodological quality. These studies investigated different types of acupuncture — including traditional needle acupuncture, electroacupuncture, dry needling, and acupressure — to treat conditions such as carpal tunnel syndrome, shoulder pain, Achilles tendinopathy, plantar fasciitis, elbow pain, and knee pain. The results showed promising but limited evidence for some specific conditions.

For carpal tunnel syndrome, two high-quality studies suggested that traditional needle acupuncture may be beneficial. One study showed that acupuncture was superior to oral corticosteroids, and another indicated it may be more effective than vitamin B1 and B6 supplements. Electroacupuncture also showed positive results for carpal tunnel syndrome, being potentially superior to placebo and equally effective as nighttime splinting. For Achilles tendinopathy, one study found that traditional acupuncture was more effective than eccentric exercises.

As for shoulder problems, electroacupuncture showed benefits superior to placebo, although the evidence for traditional acupuncture was inconsistent across different studies.

On the other hand, some conditions did not show clear benefits with acupuncture. For nonspecific upper-extremity pain, patellofemoral pain syndrome (pain in the patellar region), and plantar fasciitis, acupuncture did not demonstrate important advantages over comparison treatments. It is important to note that all observed effects were of small magnitude, and did not always reach levels that experts consider clinically meaningful for patients.

These findings have important practical implications for patients and healthcare professionals. The results suggest that acupuncture is not a universal solution for all musculoskeletal problems of the extremities. Its efficacy appears to be specific to certain conditions, and different types of acupuncture may work better for different problems. Healthcare professionals may consider traditional acupuncture as an option for patients with carpal tunnel syndrome and Achilles tendinopathy, and electroacupuncture for shoulder injuries.

For other conditions, current evidence does not justify a strong recommendation.

It is essential to recognize the limitations of this study. The research was restricted to English-language publications, which may have excluded relevant studies in other languages. In addition, because of the heterogeneous nature of the included studies — which used different acupuncture protocols, outcome measures, and patient populations — it was not possible to statistically combine their results. The relatively small number of high-quality studies also limits the strength of the conclusions.

Generalization of the results is limited to the specific conditions studied and the types of acupuncture investigated.

A concerning finding was that when the researchers included lower-quality studies in the analysis, the results became more favorable to acupuncture. This suggests that poorly conducted studies tend to exaggerate treatment benefits, reinforcing the importance of relying only on high-quality evidence to make informed clinical decisions.

In conclusion, although this systematic review provides evidence that certain types of acupuncture may be beneficial for specific conditions such as carpal tunnel syndrome and Achilles tendinopathy, the effects are modest and the evidence is still limited. Patients interested in acupuncture should discuss with their healthcare professionals whether it may be appropriate for their specific condition, considering other treatment options with more robust evidence. More high-quality research is needed to definitively establish the role of acupuncture in the treatment of musculoskeletal disorders of the extremities and to determine optimal treatment protocols.