Work 52 (2015) 707–713 DOI:10.3233/WOR-152110 IOS Press 707 Effects of bed height on the biomechanics of hospital bed entry and egress Andrew S. Merryweather a , Janice M. Morse b , Alexa K. Doig b,∗ , Nathan W. Godfrey a , Pierre Gervais c and Donald S. Bloswick a a Department of Mechanical Engineering, University of Utah, Salt Lake City, UT, USA b College of Nursing, University of Utah, Salt Lake City, UT, USA c Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada Received 17 February 2014 Accepted 17 July 2014 Abstract. BACKGROUND: Although a significant proportion of patient falls in hospitals occur in the vicinity of the hospital bed, little is known about the contribution of bed height to fall risk. OBJECTIVE: To compare lower extremity joint torques and angles during hospital bed entry and egress at two bed heights. METHODS: Twelve adults (age >55) were purposively selected and had variety of strength and mobility limitations. Biomechanical data for this pilot study were collected with three digital video cameras and processed to obtain estimates for joint torques and included angles. RESULTS: At the low bed height, hip torque for bed entry was significantly higher, and hip, knee, and ankle flexion angles were significantly smaller. The absence of significant differences in knee and ankle torques were the result of a compensation strategy that shifts the center of mass forward by flexing the torso during low bed ingress. Torque data from the egress motion were similar, however 50% of participants were unable to rise from the low bed without assistance. CONCLUSIONS: Healthcare providers should be aware that low bed heights pose safety risks to the population for which they were designed–elderly persons at high risk for falling. Keywords: Patient safety, equipment safety, accidental falls, caregiver, healthcare provider 1. Introduction In the hospital setting, a variety of studies report that patient falls at the bedside account for 12.1–77.6% of all falls [1–6]. Approximately one third of falls lead to patient harm with 4–6% of those resulting in seri- ous injury [7, 8]. Patients who suffer injurious falls have an increased length of hospital stay and a greater rate of discharge to long term care facilities, which increases health care costs [9, 10]. Healthcare providers, ∗ Address for correspondence: Alexa Doig, College of Nursing, University of Utah, 10 South 2000 East, Salt Lake City, UT 84108, USA. Tel.: +1 801 581 4381; E-mail: alexa.doig@nurs.utah.edu. including nurses, aides, and physical therapists are responsible for assessing fall risk and modifying the environment in an effort to reduce the frequency of falling [11]. In response to concerns about injury and death caused by rolling out of the bed or crawling over bed side rails, the low bed (with a bed deck height as low as 13 cm) was developed for geriatric care settings. The use of the ‘low bed’ has been recommended as an injury prevention strategy in several patient safety reports and clinical guideline papers for fall prevention [11–14]. However, there are serious safety concerns for individuals with muscle strength deficiencies and balance disorders (i.e., 1051-9815/15/$35.00 © 2015 – IOS Press and the authors. All rights reserved