Prior to designing my cane Bob researched “good cane design”. One article stood out as being excellent and he incorporated as many suggestions into his leg bone cane as possible. Following is an excerpt from this article written by Dr. Melanie Diez.
Canes Analysis and Recommendations for Improvement
An informal survey of the canes in today’s market shows they lack the most basic principles of ergonomic design. Little research could be found supporting the designs behind the canes; indeed, most canes launch a practical assault on the hand and wrist. While there are several aspects to the design of a cane (handle, shaft, base, tip), this study will concentrate on the handle designs. First, I will present a brief overview of the commonly accepted ergonomic design principles involved in handle design, followed by several examples of common cane handles.
Fraser (1980) states that the handle of a tool should conform to the natural holding position (neutral position) of the hand. In short, this means that the handle should maintain a straight wrist with minimal flexion, extension, or deviation. This can be done by incorporating an angle of 19 E” 5 E into the handle, as suggested by Emmanuel, Mills, and Bennett (1980). By reducing the angle through which the wrist itself must bend, injuries such as carpal tunnel syndrome can be minimized. Furthermore, grip strength has been shown to be maximized when the wrist is in neutral position (Terrell & Purswell, 1976). The shape of a handle should be generally cylindrical, or shaped like a truncated cone to accommodate the different degrees of flexion exhibited by each finger. Pressure from the device must not be concentrated in a small area, or along pressure-sensitive areas of the palm and fingers. Sanders and McCormick (1993) suggest a large contact surface to reduce tissue and/or nerve compression. Repetitive finger action as well as vibration exposure should also be minimized.
The article in its entirety can be found at http://ergo.human.cornell.edu/ergoprojects/97projects/diez.htm
A My 3rd Leg cane was designed with the user’s best interest in mind. The cane is strong, comfortable, and made with care for each of Bob’s customers. The unique leg bone design that attracts so much attention is a secondary benefit.