Problems with Concrete Trowel Handles
The information on this page is drawn from material produced by the CPWR. The original pdf is available at the bottom of the page. 6/01/09
Some problems
Trowels used for concrete placement and finishing work have handles cause pressure points on the palm of the hand and wrist bending. This could lead to an overuse injury to the hand or arm.
- Many users hold the trowel in this fashion. There is concentrated pressure in the base of the palm of the hand. This pressure occurs near the carpal tunnel and may contribute to the risk of carpal tunnel syndrome.
- The angle of the handle causes side bending of the wrist (ulnar deviation).
One solution
Modify the shape of the handle to fit the hand better, decrease wrist bending and provide padding to eliminate the pressure point on the palm of the hand.
- Building up the handle of the trowel with "grip kit" material provides padding to help decrease the pressure point on the palm of the hand.
- The angle of the wrist is changed slightly to reduce risk of wrist or hand injury.
An unmodified trowel
A modified trowel
How modifying the handle works
By building up the stem of the handle of the trowel, the "sharp" corner of the handle is rounded. This reduces the concentrated pressure on the palm of the hand. Also, the angle between the handle and the stem places the wrist at a more comfortable angle. The new angle reduces ulnar deviation of the wrist creating a more comfortable and less tiring grip. Cushioning will also be a benefit.
Modifying a trowel handle
Buy material that can be wrapped around the stem of the trowel handle. Be careful to not create too much thickness on the inside of the handle. There is barely enough room for the knuckles to fit between the underside of the handle and the metal ridge on the trowel.
- Ensure that the tool handle is clean and free from grease. Remove any old rubber or plastic covering. If necessary, clean the handle with an alcohol based solution.
- Wrap the material around the handle to "soften" the corner on the handle.
- Add enough padding to decrease wrist side bending when you hold the trowel. (be careful to not add too much! You should have plenty of space between your fingers and the top of the trowel.
- You may need to use an industrial hot blower (or hair dryer) to apply heat to the covering to ensure good adhesion.
Materials used to modify the example
We used an "Orthex" Vibration and shock reducing "Grip Kit" #4713 for our trials. They cost around $30 and are available from various vendors. "Grip kit" materials in one set should be adequate for wrapping several trowels.
