Affiliations: Department of Biomedical Engineering and Alfred Mann Institute for Biomedical Engineering, University of Southern California, Los Angeles, CA, USA
Note: [] Corresponding author: Hilton M. Kaplan, MD, PhD, PO Box 2337, Beverly Hills, CA 90213, USA. Tel.: +1 (310) 570 2822, Fax: +1 (310) 274 9931; E-mail: [email protected]
Abstract: Objective: Pressure ulcers (PUs) are common and debilitating wounds that arise when immobilized patients cannot shift their weight. Treatment is expensive and recurrence rates are high. Pathophysiological mechanisms include reduced bulk and perfusion of chronically atrophic muscles as well as prolonged occlusion of blood flow to soft tissues from lack of voluntary postural shifting of body weight. This has suggested that PUs might be prevented by reanimating the paralyzed muscles using neuromuscular electrical stimulation (NMES). A review of the published literature over the past 2 decades is detailed. Outcomes: Historically gluteus maximus (GM) has been an important target for NMES, but results have been difficult to interpret and suitable technology has been lacking. Conclusions: NMES of the buttock muscles appears to be valuable in terms of its trophic effects, improving vascularity and soft tissue bulk. It remains unclear, however, whether GM can actually achieve sufficient unloading of normal forces to permit blood flow in the capillary beds of the skin and muscle. Analysis of the skeletal biomechanics is required to assess the relative value of GM vs. hamstring (HS) hip extensors in this regard.
