Experimental characterization of axillary/underarm interface pressure in swing-through crutch walking

Supporting weight on the upper support of crutches is not recommended because it can lead to axillary nerve damage. Despite this warning, improper axillary loadings may still occur because of a lack of arm strength or fatigue. It is generally accepted that improper use of conventional axillary crutches contributes to axillary nerve damage, but surprisingly there are no studies characterizing axillary support/underarm configurations. In this study, we compared traditional and horizontal axillary support designs by measuring various biomechanical parameters on the axillary support during a swing-through gait while supporting weight on the axillary support. Subjects found the axillary support that remains horizontal to be more comfortable than the axillary support of axillary crutches. The higher perceived comfort may be attributed to the lower force and contact area, both average and maximum, developed on the horizontal axillary support and/or shorter excursion of the position of the center of force during a stride. These findings suggest that avoiding all weight bearing on the axillary support may be an overly conservative recommendation for supports that remain horizontal. Individuals with insufficient arm strength may benefit by considering this type of support, but because further study is needed, a physical therapist should be consulted.