Using electrical stimulation for lower extremities | Case Study
Electrical stimulation is a non-invasive, easy-to-use technique which can be used at home without needing assistance. It is used to increase circulation and ease neuropathic pain. Electrical stimulation is used in pressure ulcers (1), diabetic patients (2), venous leg ulcers (3) and venous thromboembolism prophylaxis (4-6). It is suitable for prolonged and repeated use for lower extremities.
Thermal imaging is a remote, non-contact and non-invasive technique, which is fast and can provide images in real-time. This technique makes it possible to assess lower extremities’ dynamical variations by measuring skin temperature. Thermal imaging records the natural radiation from the skin surfaces and it has no harmful radiation effects (7). It can be used as an adjuvant tool to detect venous thrombosis (8,9).
Covid-19 has changed treatment plans all over the world and has triggered wider use of telemedicine and the development of more applications for it. There was an increase in the need for home-based diagnostics with the help of specially designed medical devices. Immobilisation and lack of movement causes venous insufficiency which is a risk factor of venous embolism. Electrical stimulation is used to ease venous insufficiency symptoms and thermal imaging is used to follow-up.
Venous insufficiency and venous ulcerosis is a common diagnosis encountered by wound care doctors. The patients with these diagnoses require continuous medical and compression treatments. Some of the patients are reluctant to use compression methods and some of them have contraindications for anticoagulant drugs. Hyperbaric oxygenation and electrical stimulation were used to treat wounded patients in a wound care centre in Antalya between 2013-2019 where thermal imaging was used for follow up with the patients (10,11).
The patients who were experiencing venous ulcers needed daily wound centre visits for weeks to reach the stage of total closure of the wounds. However, the problem was the reopening of the wounds with a risk of superficial/deep venous thrombosis especially as the patients did not want to use stockings, lived in a hot climate and did not use medications. Even though the wound was treated it would often repeat itself. Strategies and management plans are needed to improve outcomes in venous circulatory care and prevention of the ulcers.
Venous thrombosis and venous thromboembolism are common causes of morbidity and mortality. A venous ulcer is a result of venous reflux or venous thrombosis typically seen around the ankle area. Some of the risk factors of venous ulcers are immobilisation, superficial/deep venous thrombosis, family history of thrombosis, infections, previous ulcers, ageing, high body mass index, venous reflux in deep veins and pregnancy. It has been presented that neuromuscular electrical stimulation systems used for the prevention of venous thromboembolism could be beneficial for patients (4,5). Electrical stimulation treatments significantly reduced the risk of deep vein thrombosis when it is compared to the patients who did not get any prophylaxis treatments (6). Usage of electrical stimulation treatments can improve venous circulation and play a major role in the prevention of venous thromboembolism and venous ulcers.
The main objective here is to identify a new method to prevent venous insufficiency, venous thrombosis and ulcerated wounds where the early management of venous insufficiency is the key prevention of future wounds. In the case study, the patient, who has a family history of deep vein thrombosis, reached his doctor by telemedicine and a commercial electrical stimulation device was used for his neuropathic pain, venous circulation improvement and a thermal camera was used for feedback and follow-up.
The patient is a 40-year-old man, non-smoker, and was active in sports before Covid-19. He had a diagnosis of disk hernia L4-S1 at age 25 with neuropathic pain on his right dorsal foot with a visual pain scale score of 6. He had meniscus surgery on his right knee at age 28. In addition, he has a history of sudden extreme pain and swelling of his right extremity during a trip in a foreign country at the age of 30 where he did not receive proper treatment. His mother has a history of deep venous thrombosis and she had a stroke at the age of 40.
He has been working at home and sitting in a chair more than 10 hours per day, six days a week during Covid-19, starting from March 2020. His complaints started with swelling in the lower legs, itching and feeling fullness around his ankles. He experienced new swollen veins in his lower extremities. He had sleeping issues due to the pain around his lower extremities. He was reluctant to use ibuprofen, paracetamol or wear compression stockings. He was advised to have daily walks and to consume plenty of water. During one of his walks, he got bitten by a bug of an unknown origin, leading to experiencing pain, swelling and a burning sensation on his extremities.
Following this, he preferred to stay at home, skipping his daily walks. He was then requested to take images using a thermal camera (adapted to a phone) of his lower extremities. Based on the clinical history and the thermal images he was prescribed local antibiotics and oral acetylsalicylic acid (100mg/daily). One week later he was then advised to try electrical stimulation treatment for his lower extremities, and to keep sending images to his consultant.
Materials and methods
The patient was placed in a semi-recumbent position for 15 minutes to maintain unaffected baseline equilibrium of the lower extremity venous flow. An electrical stimulation device was attached to the cutaneous tissue of the lower extremity with the help of electrodes. During the stimulation of the nerves and muscles, skin temperature readings were obtained with a standard mobile-phone-compatible thermal camera under ambient conditions. 20-minute electrical stimulation treatment (frequency <20 Hz, pulse width = 100μs) was applied twice a day. The images taken during the treatment were sent to the consultant.
Below are some images taken with a thermal camera during the application of the electrical stimulation and showing an increase in metabolic activity.
NuroKor Lifetech mibody modes 1 and 3 were used for 20 minutes on each local area shown above twice a day
Electrical stimulation was implemented by delivering electric pulses to the user’s skin through the electrodes. The portable and compact device, the NuroKor Lifetech mibody wearable therapy device, has multiple modes of different pulse frequencies, covering peripheral nerve stimulation (PNS) and neuromuscular stimulation (NMS) for muscle toning, firming, and strengthening. Features of the device are as follows:
- Power supply: Powered by internal 3.7V li-ion battery
- Waveform and wave shape: Biphasic rectangular wave pulse
- Pulse duration: 100 us (microseconds)
- Pulse frequency: 1-160 Hz (Hz=vibration per second)
- Output Voltage: Max. 75Vpp ±20% (at 500ohm load)
- KorOS2 dualwave technology
- Output intensity: 0 to 10 levels, adjustable
- Modes: 6 auto modes
- Size: 373.6 x 40 x 12mm
Thermal images were captured using a long-wave infrared (LWIR) camera module. It captures infrared radiation input in its nominal response wavelength band (from 8 to 14 microns) and outputs a thermal image using standard cell-phone-compatible power supplies. Features of the device are as follows:
- Fast (<0.5 sec) time to image
- 51-deg HFOV, 63.5-deg diagonal
- 80 (h) × 60 (v) active pixels
- Thermal sensitivity, <50 mK
- Optional temperature-stable output to support radiometric processing
Thermal imaging is a harmless application, which was used as a follow-up method during the electrical stimulation treatments.
Venous insufficiency is a vascular disease that occurs when the venous wall and/or valves in the leg veins do not work properly. Calf muscles and the muscles in the feet must contract sufficiently to squeeze veins and push blood to the heart. Immobility due to Covid-19 and long work hours at home triggers unhealthy living conditions and can increase the risk of issues in the lower extremities. Electrical stimulation treatment can be used as a helpful method to prevent venous diseases during these conditions.
This case report showed that electrical stimulation treatment increased the activity of the metabolism, which was captured with the thermal camera. In this case, electrical stimulation treatment was also used to ease the patient’s neuropathic pain - the visual analogue pain scale score decreased from 6 to 2 after the second day of the treatment. No side effects were observed during or after the electrical stimulation treatments.
Undesirable clotting in lower extremities may happen due to limited mobility. This could be prevented by medications or compression methods. Neuromuscular electrical stimulation systems provide impulses to lower extremities to encourage involuntary mechanical contractions of the muscles and have been used for the prevention of venous diseases. Neuromuscular electrical stimulation increases venous blood flow and is well tolerated (6). Electrical stimulation promotes tissue oxygenation and reduces oedema. It has also been shown to have beneficial effects in wound healing (12) which may also affect the rise of epidermal growth factors and their receptors (13,14). Furthermore, electrical stimulation may have an antibacterial effect that helps diminish infection and improve healing (15).
Commercially available electrical stimulation treatments can be used safely at home with the guidance of health care professionals. Easy-to-use, handy electrical stimulation devices can play an important role in lower extremity diseases and can be combined with thermal imaging devices for follow-up treatments to show metabolic activity and early detection of illnesses.
- Arora M, Harvey LA, Glinsky JV, Nier L, Lavrencic L, Kifley A, Cameron ID. Electrical stimulation for treating pressure ulcers. Cochrane Database of Systematic Reviews 2020, Issue 1. Art. No.: CD012196. DOI: 10.1002/14651858.CD012196.pub2.
- Baker LL, Chambers R, DeMuth SK, Villar F. Effects of electrical stimulation on wound healing in patients with diabetic ulcers. Diabetes Care. 1997;20(3):405-412. doi:10.2337/diacare.20.3.405
- Miller C, McGuiness W, Wilson S, et al. Venous leg ulcer healing with electric stimulation therapy: a pilot randomised controlled trial. J Wound Care. 2017;26(3):88-98. doi:10.12968/jowc.2017.26.3.88
- Nicolaides AN, Kakkar VV, Field ES, Fish P. Optimal electrical stimulus for prevention of deep vein thrombosis. Br Med J. 1972;3(5829):756-758. doi:10.1136/bmj.3.5829.756
- Hajibandeh S, Hajibandeh S, Antoniou GA, Scurr JR, Torella F. Neuromuscular electrical stimulation for thromboprophylaxis: A systematic review. Phlebology. 2015;30(9):589-602. doi:10.1177/0268355514567731
- Ravikumar R, Williams KJ, Babber A, et al. Neuromuscular electrical stimulation for the prevention of venous thromboembolism. Phlebology. 2018;33(6):367-378. doi:10.1177/0268355517710130
- Fobbe F, Felsenberg D, Laass C, Sörensen R. Tele-Thermographie zur Diagnostik tiefer Bein- und Beckenvenenthrombosen [Tele-thermography in the diagnosis of deep leg and pelvic venous thrombosis]. Rofo. 1988;149(1):31-34. doi:10.1055/s-2008-1048289
- Harding JR. Investigating deep venous thrombosis with infrared imaging. IEEE Engineering in Medicine and Biology Magazine: the Quarterly Magazine of the Engineering in Medicine & Biology Society. 1998 Jul-Aug;17(4):43-46. DOI: 10.1109/51.687962.
- J. R. Harding, "Investigating deep venous thrombosis with infrared imaging," in IEEE Engineering in Medicine and Biology Magazine, vol. 17, no. 4, pp. 43-46, July-Aug. 1998, doi: 10.1109/51.687962.
- Tezer Irem, Fabricius Christian, 42nd Annual Scientific Meeting of the European Underwater& Baromedical Society, (EUBS) 2015, Hyperbaric oxygen and electrical stimulation treatment of systemic sclerosis non healing ulcers: a case report
- Fabricius Christian, Tezer Irem (EUBS) 2015, Amsterdam, Netherlands, Thermal imaging of non-healing wounds
- Ud-Din S, Bayat A. Electrical Stimulation and Cutaneous Wound Healing: A Review of Clinical Evidence. Healthcare (Basel). 2014;2(4):445-467. Published 2014 Oct 27. doi:10.3390/healthcare2040445
- Ud-Din S, Sebastian A, Giddings P, et al. Angiogenesis is induced and wound size is reduced by electrical stimulation in an acute wound healing model in human skin. PLoS One. 2015;10(4):e0124502. Published 2015 Apr 30. doi:10.1371/journal.pone.0124502
- Liebano RE, Machado AF. Vascular Endothelial Growth Factor Release Following Electrical Stimulation in Human Subjects. Adv Wound Care (New Rochelle). 2014;3(2):98-103. doi:10.1089/wound.2013.0427
- Asadi MR, Torkaman G. Bacterial Inhibition by Electrical Stimulation. Adv Wound Care (New Rochelle). 2014;3(2):91-97. doi:10.1089/wound.2012.0410