OVERVIEW.

McConnell¹ provides practical, nontechnical advice to clinicians to lessen the risk of electric shock with patients (also see Hydrotherapy, Biofeedback).

OVERVIEW.

Electrical stimulation (ES) uses alternating or direct current to accomplish various therapeutic aims including (1) to increase strength and endurance of innervated muscle (NMES), (2) to modulate pain (TENS), (3) to reduce edema (HVPC) and enhance healing, and (4) to stimulate denervated muscle (DC). It is also used (5) to deliver transdermal drugs using direct current (see Iontophoresis) and (6) to activate muscles during functional activities (see Functional electrical stimulation).¹

The literature tends to treat electrical stimulation either in general terms, or alternatively, addresses motor (NEMS, or powered muscle stimulator) and pain modulation (TENS) modality concerns separately (as the FDA does).^2,3 In this text, I differentiate among NMES, ES, and TENS concerns.

SUMMARY: CONTRAINDICATIONS AND PRECAUTIONS.

Thirteen sources together identify a total of 71 concerns for electrical stimulation (TENS, ES, and NMES). These concerns are listed under 16 categories. The largest number of concerns is noted as follows: For NMES, the FDA identifies 26 concerns. For TENS, the FDA and a PT both identify 14 concerns. And for ES, a PT identifies 14 concerns. The top three concerns, with all sources combined (N = 13), are pacemaker devices (92%), pregnancy (92%), and carotid sinus stimulation (85%).

GUIDELINE SIMILARITIES AND DIFFERENCES.

NEMS, ES, and TENS shared some concerns: demand pacemakers, pregnancy, and treatments over the carotid sinus. On the other hand, modality-specific concerns were also apparent in this sample. For example, TENS had distinct concerns for undiagnosed pain, suppression of protective sensory mechanisms, and narcotic/drug use. This would make sense because TENS is used primarily for pain control. Also noteworthy, procedural concerns appear more common during TENS use (17 procedural concerns) than for NEMS (6 procedural concerns). In contrast, NEMS guidelines contain more motion-related concerns such as thrombophlebitis, fractures, hemorrhaging, the operation of machinery (e.g., driving), and conditions where movement is contraindicated. Again, this seems logical, in that NEMS affects muscle contraction.

OTHER ISSUES.

(1) Cross-infection: In a 2000 laboratory-based study, Lambert et al⁴ sampled microorganisms on suction cups and sponges used during interferential therapy and demonstrated the possibility of cross infection in a healthy volunteer. (2) Partially denervated muscle and direct current: In a 1979 Nature publication, Brown and Holland⁵ reported that direct current interfered with sprouting in partially denervated muscle. In a critique, one source¹ argued that the parameters used in Brown and Holland’s study were unlike those used in patients treated with denervated muscle. (3) Brachial plexus injury: In 1986, Mubarak and Wyatt⁶ reported a 13-year-old white girl with idiopathic scoliosis who received electrical stimulation to the trunk for scoliosis and subsequently experienced upper/middle brachial plexus injury possibly from stimulus-related shoulder girdle hyperextension near the thoracic outlet. (4) RA: In 1981, Griffin and McClure⁷ reported a 43-year-old female with RA who experienced a possible circulatory-related exacerbation of her symptoms following TENS use.

Notes: A few sources make recommendations for more than one modality. For NMES: only two sources apply, FDA used the term “powered muscle stimulator.” Abbreviations in table: T = transcutaneous neuromuscular stimulation (TENS); M = neuromuscular electrical stimulation (NMES); E = electrical stimulation (general, not specified).