01 Dec Percutaneous Electrical Nerve Stimulation
Percutaneous Electrical Nerve Stimulation (PENS) is a relatively modern neurostimulation therapy for the treatment of chronic neuropathic pain. PENS is similar to TENS (Transcutaneous Electrical Nerve Stimulation), a therapy in which a low voltage electrical current is delivered to the area of pain via electrodes. With TENS, the electrodes are placed onto the skin (transcutaneous), however, with PENS, the current is delivered into the subcutaneous (fatty) tissue close to the pain generating nerve via an “electro-acupuncture” type needle.
Unlike radiofrequency neurotomy/ablation therapies that deliver heat to damage pain generating nerves and interrupt pain signalling, the delivery of low voltage electrical current aims to desensitise the nerve to pain signals and hence provide pain relief. This is similar to peripheral nerve neuromodulation, without the need for invasive surgery/implants.
PENS therapy is used to treat chronic neuropathic pain conditions, such as nerve hypersensitivity, neuropathic headache, chronic post-surgical pain and peripheral diabetic neuropathy. PENS has also been shown to provide short term relief of low back pain and sciatica.
PENS is a minimally invasive procedure that can be performed in a day surgery setting.
The patient will be admitted by a nurse and change into a gown before being positioned onto the procedure table. The doctor will mark the target area with a pen and inject some local anaesthetic into the area to numb the treatment site. A single needle or a pair of fine-gauge needles will then be inserted into the soft tissue. An earthing pad will be placed on the skin somewhere near the target area. The needle(s) are then connected to a low voltage pulse generator and a low voltage electrical current is delivered to the area. The duration of the electrostimulation will vary, typically between 15 to 60 minutes.
Possible adverse effects include temporary exacerbation of pain, tenderness and bruising at the target site. There is a very low risk of serious side effects, such as infection and nerve damage.
The degree and duration of pain relief is highly dependent on the condition and the individual. If successful, PENS may be repeated for sustained pain relief / management.
References & Further Reading:
- National Institute for Health and Care Excellence (UK). Percutaneous electrical nerve stimulation for refractory neuropathic pain. 2016: https://www.nice.org.uk/guidance/ipg450
- Victoria Pain Specialists. Using PENS for pain? Oct 11, 2015: http://vicpain.com.au/patient/2015/10/11/using-PENS-for-pain.html
- Yokoyama M, Sun X, Oku S, et al Comparison of percutaneous electrical nerve stimulation with transcutaneous electrical nerve stimulation for long-term pain relief in patients with chronic low back pain. Anesthesia and Analgesia. 2004:98:1552-6. https://www.ncbi.nlm.nih.gov/pubmed/15155304
- Ghoname EA, Craig WF, White PF, et al. Percutaneous electrical nerve stimulation for low back pain: a randomized crossover study. JAMA. 1999:281:818-23. http://jamanetwork.com/journals/jama/fullarticle/188949
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