Spinal Cord Injury (SCI) refers to damage to the spinal cord that disrupts communication between the brain and the rest of the body. This damage can be complete or incomplete, depending on whether the spinal cord is fully severed or only partially damaged. The consequences can range from partial weakness to full paralysis below the injury site. Functional Electrical Stimulation (FES) is a widely used approach to support motor recovery, maintain muscle health, and enhance mobility. FES can help re-educate neural pathways by delivering controlled electrical impulses to targeted muscles.

According to the World Health Organisation,

Globally, over 15 million people are living with spinal cord injury (SCI) [1].

Most SCI cases are due to trauma, including falls, road traffic injuries or violence, and are thus preventable [1].
SCI is a major cause of long-term disability, accounting for over 4.5 million years of life lived with disability in 2021. [1]

Symptoms and Complications

The symptoms of SCI vary widely based on the injury's location and severity, but may include:

Secondary complications like pressure ulcers, respiratory infections, and blood clots are also common, particularly in those with high-level injuries.

Impact on Daily Life

Living with SCI impacts nearly all aspects of daily life, from mobility and employment to independence and social participation. The physical, emotional, and financial burden can be overwhelming for both patients and caregivers. Rehabilitation is often long-term and requires a combination of medical, physical, and psychological support.

Functional Electrical Stimulation

Functional Electrical Stimulation (FES) uses electrical pulses to stimulate peripheral nerves and generate muscle contractions in individuals who have lost motor function due to neurological conditions. In the context of SCI, FES can activate paralysed or weakened muscles to support movement. The stimulation is typically applied through surface electrodes placed on the skin over specific muscle groups. These contractions can be coordinated to achieve functional tasks like grasping, walking, or cycling.

FES plays an important role in neurorehabilitation, particularly for individuals with spinal cord injuries and other neurological conditions. More sophisticated than traditional electrical stimulation, FES often incorporates precise timing and coordination, using motion sensors, stimulation protocols, or even immersive XR-based systems to enhance outcomes. Its therapeutic benefits include reducing muscle atrophy, improving blood circulation, lowering spasticity, and promoting bone density. Crucially, FES also supports neuroplasticity, the brain and spinal cord's ability to reorganise and form new neural connections, which is essential for regaining lost motor functions after injury.

How FES Supports SCI Recovery

The impact of FES in spinal cord injury recovery is multifaceted:

Muscle Re-education: FES allows targeted activation of muscles even in cases of paralysis, helping patients re-learn movement patterns.
Cardiovascular Health: Repeated FES cycling or gait training improves cardiovascular function in individuals with limited mobility.
Neuroplasticity: Though SCI interrupts brain-body communication, FES offers external stimulation that may help "re-train" neural circuits, especially in incomplete injuries.
Psychological Benefits: Active participation in therapy, even when assisted, has been linked to improved mood, confidence, and motivation.

Clinical research supports the use of FES in rehabilitation for individuals with stroke and spinal cord injuries, showing improvements in specific motor functions. In spinal cord injury cases, particularly incomplete cervical injuries, FES therapy has been associated with enhanced self-care abilities, with sustained benefits observed over time. [2]

One pilot study by Popovic et al. explored the use of Functional Electrical Therapy (FET) for retraining grasp in individuals with chronic cervical SCI. The findings showed promising improvements in hand function, indicating that even long after injury, meaningful functional gains may be achievable with FES-assisted therapy, though larger-scale studies are needed to confirm these results. [3]

Functional Electrical Stimulation Cycling for Spinal Cord Injury

FES-Induced Cycling in Complete SCI: A Simpler Control Method Based on Inertial Sensors

FES Cycling is one of the common applications of this technology for individuals with SCI. It enables paralysed legs to pedal a stationary bike by triggering muscle contractions in a coordinated sequence [4]. In addition to the benefits of FES mentioned above, FES bike can lead to:

Increased muscle mass, muscle strength and power output
Improved aerobic capacity
Enhanced circulation and metabolic function
Reduced spasticity

A detailed review by van der Scheer et al [4] highlights how FES cycling supports physical health, but also reduces the risk of secondary complications like pressure ulcers and deep vein thrombosis.

Thanks to its wide-ranging physiological benefits, FES cycling has been included as an official discipline in CYBATHLON—an international competition that showcases advanced assistive technologies designed to support people with disabilities in everyday life. This inclusion highlights the growing recognition of FES cycling as not just a therapeutic tool, but also a means of promoting independence, physical activity, and real-world functionality for individuals with spinal cord injuries. [5]

v-health Mobile

One of our recent clinical case studies highlights the potential of personalised FES therapy in SCI recovery, using the v-health Mobile in functional training with spinal cord injury and stroke patients. The primary goals were to support grasp and release functions using wrist flexors and extensors, enable functional reaching through the pairing of deltoid, triceps, and wrist extensors, facilitate a hand-to-mouth task via coordinated wrist and elbow flexion, and assist with chair push-ups using triceps in manual stimulation mode.

The protocol integrated a 2-channel FES setup with v-health Mobile’s Custom Sequence and Manual Mode, targeting specific muscle groups to support daily functional tasks. As a result, the patients were able to perform task-oriented movements with assistance, building coordination and reducing effort.

Read the Full Case Study

References:

[1] World Health Organisation. (2024, April 16). Spinal cord injury. https://www.who.int/news-room/fact-sheets/detail/spinal-cord-injury

[2] Kapadia N, Moineau B, Popovic MR. Functional Electrical Stimulation Therapy for Retraining Reaching and Grasping After Spinal Cord Injury and Stroke. Front Neurosci. 2020 Jul 9;14:718. doi: 10.3389/fnins.2020.00718. PMID: 32742254; PMCID: PMC7364342.

[3] Popovic, M. R., Kapadia, N., Zivanovic, V., Furlan, J. C., Craven, B. C., McGillivray, C., & O’Connor, P. (2006). Functional electrical therapy: retraining grasping in spinal cord injury. Spinal Cord, 44(3), 143–151. https://pubmed.ncbi.nlm.nih.gov/16130018/

[4] van der Scheer, J.W., Goosey-Tolfrey, V.L., Valentino, S.E. et al. Functional electrical stimulation cycling exercise after spinal cord injury: a systematic review of health and fitness-related outcomes. J NeuroEngineering Rehabil 18, 99 (2021). https://doi.org/10.1186/s12984-021-00882-8

[5] CYBATHLON; Functional Electrical Stimulation Bike Race https://cybathlon.com/en/event/disciplines/fes

Spinal Cord Injury Recovery with Functional Electrical Stimulation