What type of Functional Electrical Stimulation (FES) device is recommended for an adult patient with wrist drop and intact flexor function, likely due to a neurological condition such as stroke or spinal cord injury?

Functional Electrical Stimulation Device for Wrist Drop

Use a functional electrical stimulation (FES) device with surface electrodes applied to the wrist and forearm extensor muscles to directly stimulate muscle contraction in patients with wrist drop. 1, 2

Device Type and Application

The recommended gadget is a surface electrode FES system that applies electrical stimulation transcutaneously to the radial nerve and wrist extensor muscles. 2, 3 This differs from implantable systems and works by causing controlled muscle contractions through external electrodes placed on the skin over the forearm extensor compartment. 1, 4

Specific Technical Approach

• Target the proximal radial nerve bundle proximal to the elbow and the wrist/finger extensor muscle groups using transcutaneous electrode arrays. 3
• The device should allow adjustment of stimulation intensity and location to elicit finger and wrist extension either independently or in coordinated patterns. 3
• Surface stimulation electrodes are preferred over implanted systems for initial therapy, as they are non-invasive and can be adjusted based on patient response. 5

Clinical Implementation Protocol

Timing of Intervention

• Apply FES within the first 6 months post-stroke for optimal outcomes, as this is the critical window for motor recovery. 2, 6
• FES is typically used as a time-limited intervention during the first several weeks after acute stroke onset. 1, 6

Treatment Structure

• Combine FES with intensive task-specific wrist extension practice rather than using stimulation alone. 2, 6
• Each session should last 45-60 minutes maximum to prevent excessive fatigue. 5
• The stimulation should produce minimum to virtually no pain during application. 5

Expected Outcomes

• Improved muscle force in wrist extension is the primary measurable outcome supported by meta-analysis of RCTs. 1, 6
• Evidence shows short-term increases in motor strength and motor control with reduction in impairment severity. 1

Critical Caveat About Functional Gains

The evidence demonstrates improved muscle force but does NOT consistently show improvements in functional outcomes or activities of daily living. 1 This means the device will strengthen the wrist extensors and reduce the visible wrist drop, but may not translate to better hand function in real-world tasks. 6 The benefits may only be evident when the stimulator is actively being used. 6

Integration with Rehabilitation

• Do NOT use FES as a standalone treatment - it must be combined with active motor practice. 6, 7
• Pair the electrical stimulation with progressive task-specific wrist extension exercises starting with supported movements on a table surface, advancing to unsupported movements. 2
• Add structured resistance training starting at 40% of 1-repetition maximum with 10-15 repetitions, progressing to 41-60% intensity as tolerated. 2

What NOT to Do

• Avoid static splinting or immobilization of the wrist, as this prevents restoration of normal movement and promotes learned non-use. 2
• Do not position the wrist at end ranges for prolonged periods, which exacerbates symptoms and impedes recovery. 2

Advanced Options for Specific Presentations

For patients with abnormal co-contraction patterns who have some voluntary movement, consider EMG-driven neuromuscular electrical stimulation with robot-assisted wrist training as a more sophisticated first-line option. 7 This approach uses the patient's own muscle signals to trigger the stimulation, creating a more physiological recruitment pattern. 6, 8