Botulinum toxin A improves shoulder pain and movement in patients with stroke

This study investigated the effectiveness of Botulinum toxin A (Botox; BTA) in treating shoulder pain in stroke survivors. Researchers suggested that BTA improves pain and shoulder movement in these patients.

A stroke happens when the blood flow to the brain is cut off. This may be due to a blood clot or a burst blood vessel. Shoulder pain is a common complication after stroke and is present in 54 to 75% of stroke survivors. It affects the mental well-being and quality of life of these patients.

The standard treatment for shoulder pain includes physical therapy. Local injection of therapy drugs such as BTA is also part of the conventional treatment. BTA blocks nerve signals improving muscle stiffness. Prior studies suggested that it improves shoulder pain and function. However, its effectiveness varied between studies. The right dosage and whether BTA should be given alone or in combination is still not clear.

This study reviewed 9 other studies including information about 301 stroke survivors with shoulder pain. patients received either BTA injection with or without rehabilitation therapy or control treatments. Control treatments included injections with a steroid drug or a placebo drug with or without the same rehabilitation therapy. 

Patients who received BTA had a significant decrease in shoulder pain at 1, 4, and 12 weeks after treatment. Moreover, these patients also had an increase in shoulder movement at 1, 4, and 12 weeks after treatment. Shoulder rotation also increased at 1, 2, and 4 weeks after treatment.

This study concluded that BTA shoulder injections provided pain relief and increased shoulder function in patients with stroke.

This study included studies with very small patient populations. Also, patients had different types of stroke and were at different stages of stroke recovery. This might have influenced the results. Further studies are needed.