Despite difficulties in comparing data across nations, mortality from COVID-19 is clearly higher in some countries than in others. Many factors could have a role in this disparity, including differences in proportion of elderly people in a population, general health, accessibility and quality of healthcare, and socioeconomic status. One mostly overlooked factor that could influence outcome of COVID-19 is the relative vitamin D status of populations. Because people are advised to stay at home as much as possible, the government health agencies of Great Britain have recommended that people take vitamin D supplements through summer and autumn during this pandemic. Vitamin D supplementation could be especially important for older people as they are at high risk of poor outcome from COVID-19 and of vitamin D deficiency.
Sometimes, an orthopedic aid or orthosis is necessary. Orthopedic aids include, among others, cushioned heels (providing a shock-absorbing function) and wedges to elevate the inner or outer side of the shoe, thereby correcting the axis to a certain extent and taking mechanical stress off the affected part of the joint. Some patients initially do not want to accept these aids, but can be made more amenable to them by adequate patient education and the active involvement of orthopedic technicians and shoemakers. Knee orthoses are also intended to relieve pain and improve joint function (11). In a Cochrane Review, five controlled trials (evidence level Ib) were evaluated (e22). Patients wearing an orthosis were found to have significantly less pain and better function than patients in the control groups.