Some 45% to 65% of elderly nursing home residents suffer
from OA [7,8]. The knee is one of the most commonly
affected sites [9]. Undertreatment of pain in nursing home
residents has serious consequences for the quality of their
sleep [10], and the combination of unrelieved pain and
sleep disturbance further exacerbates existing cognitive
impairment [11] and leads to depression [12] and disruptive
behavior [13], while also increasing the considerable
burden and costs of caring for elders.