View Full Version : T12-L1 shear forces

Richard Lefebvre
12-18-1998, 01:05 AM
A couple of weeks ago, I received a problem to solve regarding shear forces appearing at T12-L1 level following, during a rock climbing activity, a rappel descending technique using 3 rope contour around the waist. The climber was unfortunately asked to take a position with both arms open on each body side like the Christ on the Cross, the body in straight line positioned perpendicular to the rock wall and mainly parallel to the ground (wall slope being about 80 degrees in reference to the ground). This not recommended climber position apparently resulted into damage at the thoraco-lumbar region (herniated disk) with potential sensory or motor affection.

Considering that most of the work is done around impact, compression and shear forces during lifting, is there any references I may look at to get information regarding shear forces and any standards (like NIOSH in lifting) in that matter.

Thank you in advance for any help and best wishes for the New Year.

Richard Lefebvre, Ph.D.
Département des Sciences de l'activité physique
Université du Québec à Trois-Rivières
C.P. 500, Trois-Rivières (Québec) G9A 5H7