Understanding the Contraindications of Functional Electrical Stimulation (FES)

Functional Electrical Stimulation (FES) is a therapeutic intervention in which small electrical pulses are used to facilitate contractions in muscles that are weakened or paralyzed due to neurological injury or illness. While FES offers numerous clinical benefits, it’s crucial to be aware of its contraindications to ensure safe and effective use. In this blog post, we will delve into the contraindications of FES, helping practitioners and patients make informed decisions.

What is Functional Electrical Stimulation (FES)?

FES involves applying electrical currents to specific muscles through surface electrodes. Stimulating muscles through FES can help increase muscle strength, enhance motor function, decrease spasticity and reduce muscle atrophy, among other potential benefits. It is commonly used in rehabilitation for individuals with conditions such as spinal cord injuries, stroke, brain injury, multiple sclerosis, and cerebral palsy.

Absolute Contraindications

Certain conditions make the use of FES unsafe due to the high risk of adverse effects. These include:

1. Pacemakers and Implanted Defibrillators: FES can interfere with the functioning of these devices, potentially leading to life-threatening complications. However, because of the different types of these devices and how they operate, it is worth speaking with your physician to determine if FES can be used safely with your specific implant.
2. Epilepsy: The electrical stimulation can potentially trigger seizures in individuals with uncontrolled epilepsy. If your epilepsy is controlled, we recommend speaking with your neurologist.
3. Pregnancy: The safety of FES during pregnancy has not been established.
4. Severe Osteoporosis: FES can induce muscle contractions that might lead to fractures in individuals with severe osteoporosis.
5. The use of FES is also not recommended over the following areas: phrenic nerve, eyes, gonads, areas with known peripheral vascular disease (including DVT and thrombophlebitis), carotid bodies, and areas with active osteomyelitis or hemorrhage. 

Relative Contraindications

In some cases, FES can be used with caution. Listed below are circumstances in which a patient should seek specific medical clearance prior to use:

1. Skin Conditions: Open wounds, infections, or skin irritations at the electrode site can worsen with the use of FES. It’s important to ensure the skin is healthy before applying the electrodes.
2. Malignant Tumors: Stimulating muscles near a tumor could potentially promote cell growth.
3. New Metal Implants: While not an absolute contraindication, the presence of recent metal implants near the stimulation site can cause discomfort or heat during treatment; typical guidance is to avoid FES until 3 months after implant surgery.
4. Uncontrolled Hypertension or Hypotension: The autonomic responses induced by FES can affect blood pressure regulation, posing a risk for individuals with uncontrolled blood pressure issues.

Special Considerations

When considering FES, it’s also important to evaluate the following factors:

1. Cognitive or Communication Impairment: Patients with significant cognitive and/or communicative deficits may not be able to provide feedback or understand the instructions necessary for safe FES application.
2. Cardiac Conditions: Individuals with a history of cardiac issues should undergo a thorough evaluation to determine if FES is safe for them.
3. When combining FES and cycling, the patient will need adequate range of motion in the extremities as well as no major musculoskeletal concerns to exercise safely. 

Ensuring Safe Use of FES

To ensure the safe and effective use of FES, healthcare providers should:

1. Conduct Comprehensive Assessments: Evaluate each patient’s medical history, current health status, and specific contraindications before initiating FES therapy.
2. Monitor Treatment: Regularly monitor the patient’s response to FES, adjusting the treatment parameters as necessary.
3. Educate Patients: Provide thorough education to patients and caregivers about the proper use of FES, including how to recognize and report any adverse reactions.
4. Stay Informed: Keep up-to-date with the latest research and guidelines on FES to ensure best practices are followed.

Conclusion

Functional Electrical Stimulation is a valuable tool in rehabilitation; however, as with any other modality, it is crucial to fully understand the contraindications to ensure patient safety. By understanding and adhering to these contraindications, healthcare providers can optimize the benefits of FES while minimizing the risk of adverse effects.If you or someone you know is considering FES therapy, contact MYOLYN’s  knowledgeable team to learn more. You can also browse our User Stories to read our users’ accounts of how this technology has helped them reach their rehabilitation goals!