This document discusses levers and their application in physiotherapy. It defines the three types of levers - first, second, and third order - and provides examples of their clinical use. Torque, force couples, and the resolution of forces are also explained. The roles of bones, joints, and muscles as lever systems in the body are described. Finally, references used in creating the document are listed.

1. Padmashree Dr. Vitthalrao Vikhe Patil
College of Physiotherapy
Vadgoan Gupta,
Ahmednagar(M.S.)
414111
www.vims.edu.in

2. By- Dr. Vrushali S. Jadhav
PG in Musculoskeletal Sciences
Guide- Dr. Deepak Anap
Associate Professor

3. 
 Lever
 Type of lever
 Clinical application in physiotherapy
 Force couple
 Resolution of forces
Objective

4. 
 Principle of rigid bar
 3 forces of mechanical lever-
Axis(A)
Weight(W or R)
Moving force(F or E)
Lever

5. 
 The bones and muscles in the body act as lever systems
Bones—levers
Joints---fulcrum
Muscles contracting ---effort
Resistance(load)-----COG of part moved or object to be lifted

6. 
First Order- Balance
Second Order- Power
Third Order- Speed
Order of Lever

7. 
 First order lever
Clinical application in
Physiotherapy

8. 
Second Order Lever

9. 
Third Order Lever

10. 

11. 
Torque
The rotary effect of a force about an axis of rotation.
T = Fd
Thus, both the magnitude of a force and the length of its
moment arm equally affect the amount of
torque(rotation) generated

12. 
Force Couple
 Pure force couple-
rotational motion
 In General- both
translational & rotational
motion

13. 
 Force applied at 90deg. ,
produce greater torque
 Perpendicular force( rotatory
component)
 Parallel force (Translatory
component)
Resolution Of Forces

14. 
 To visualize the effect of such angular forces on the
body.
 To determine the torque produced by the forces.
 To calculate the magnitude of unknown muscle &
joint forces.
Uses

15. 

16. 
Muscle Role Versus Angle Of Attachment
Mechanical advantage is greater at 90 elbow flexion

17. 
 Joint structure and function by Cynthia Norkin, 4th
edition.
 Brunstorm’s Clinical Kinesiology, 5th edition.
 Kinesiology by Carol Oatis, 2nd edition.
 Biomechanical basis of Human Movement by Joseph
Hamill, 2nd edition.
 The principle of exercise therapy by Dena Gardiner,
4th edition.
References

18. 
Thank You