HandShoe Mouse: Ergonomic Mouse Backed By Ergonomic Research

Examples of complaints, caused by gripping and pinching are:

• head aches radiating from the neck area
• tingling feeling in arms and hands
• reduced mobility of the head
• loss of force in the hands
• obstruction of blood flow, numb feeling

Complaints may also increase as a result of stress.

Continuous Lifting of Fingers ("Hovering")

The Erasmus University studies have also shown that, when using a conventional computer mouse, you are obliged to almost continuously lift the fingers above the mouse to prevent inadvertent switching.

This may lead to over exertion of certain muscles (the extensor muscles) in your arms and hands.
As a result of this exertion, excessive tension in the deep neck muscles may occur. When these muscles are tense they can virtually close the costoclavicular gate between the first rib and the clavicular bone.

Another aspect addressed by professor Van Zwieten of Hasselt University in Belgium is the highly intense use of fingers, for example with a conventional computer mouse. This may lead to hand- or finger complaints. To understand the finger positions concerned, we analysed some of its joints by functional anatomical research. 
It appears that the functional demand of a stabilised arch of the finger will be met, by designing and using a computer mouse that is pre-shaped to prevent disorders caused by intense use of the mouse.
In current e-learning practice, each student’s fingers, hand, and even whole upper extremity, may benefit from ergonomically safe working conditions, thus using the computer successfully.

A statically and dynamically stabilised finger arch as is enabled by the HandShoe Mouse is needed to prevent complaints.
(ref: publication of professors K.J. van Zwieten, K.P.Schmidt et al, 2010)

Blood vessels and nerves that pass through this gate may be pinched and the blood circulation may thus be hampered (possibly also resulting in carpal tunnel syndrome).

Pronation of the forearm

When a (seated) person shifts his hand, palm downwards (fully pronated forearm), to and from his body, e.g. by moving a conventional computer mouse over a desk top, the Radius gradually crosses the Ulna. This is partially realised by contraction of the muscle Pronator Teres.
Crossing of Radius over Ulna is defined as pronation of the forearm.
 
Such frequent movements could result in Repetitive Strain Injury complaints. (ref: publications Russian Scientific Practical Conference, Nov. 2008 and Health Conference St. Petersburg, Nov. 2009 of professors K.J. van Zwieten, K.P.Schmidt et al, 2008)

So called neutral or "handshake" position

Next to the above subject, "pronation of the forearm", it is interesting to observe the behaviour of the membrane which sits between Ulna and Radius, the two forearm bones. For example, muscles of the forearm attach to this membrane. The membrane also transfers forces from the radius, to the ulna and to the humerus. 

In vitro studies by Professors K.J. van Zwieten, K.P.Schmidt et al, University of Hasselt demonstrated that the use of a vertical PC-mouse in “handshake” positions should be re-evaluated.(for publication click here)

The so called neutral or “handshake” position results in a maximally taut membrane between Ulna and Radius. In general thumb and index finger long muscles originate from this forearm interosseous membrane. Therefore the need to grip and pinch a vertical mouse results in unnecessary strains in the already taut membrane and may cause physical complaints. (for publication click here)

Studies with regard to the design of the PC-mouse by National Taiwan University (for publication click here) and Erasamus University Medical Center (on this page) have resulted in a slightly slanted mouse body as with the HandShoe Mouse to prevent these physical complaints.