The document discusses vicarious movements, defined as unnatural movements resulting from muscle paralysis or inhibition, where other muscles compensate for the action of a paralyzed prime mover. It details six types of trick movements: direct/indirect substitution, accessory insertion, tendon action, rebound, gravity assistance, and anomalous nerve supply, each with examples. References cited include works on muscle testing and function.

1. Vicarious movements
Dr. Arunima Biswas

2. CONTENTS
 What are trick movements?
 Types of trick movements
 Examples of each type of trick movement
 References

3. Definition
 Unnatural movements seen when muscle is
paralyzed or inhibited
 It is taking over of the action of a paralyzed prime
mover by another group of muscles
 It is also known as substitution movement

4. Types of trick movements
1. Direct/ indirect substitution
2. Accessory insertion
3. Tendon action
4. Rebound
5. Gravity
6. Anomalous nerve supply

5. 1. Direct/ indirect substitution
A. Another prime mover will substitute for paralyzed
prime mover muscle
 E.g. weakness/ paralysis of supinator muscle
Muscle substituted Trick movement
Biceps brachii Supination along with elbow flexion

6. B. Fixator muscle will produce movement for prime
mover/ agonist muscle
 E.g. weak/ paralyzed hip abductors
Muscle substituted Trick movement
Lateral abdominals Pelvis elevation

7. C. Other favourable muscles placed in the region will
contract to position the joint in a new position so
that the other muscle performs the test motion in
the new modified position
 E.g. Deltoid paralysis
Favourable muscle New position Other muscle
External rotators Externally rotate Biceps will contract to produce
shoulder abduction

8. D. Other muscle may contract to assist the weak
muscle
 E.g. Weakness/ paralysis of Biceps
Muscle substituted Trick movement
Shoulder flexors Shoulder flexes during elbow flexion

9. 2. Accessory insertion
 The insertion of muscle is such that when the
muscle contracts, it helps to perform movements
of the weak/ paralyzed muscles
 E.g. weakness/ paralysis of EPL
Substituted muscle Insertion Trick movement
APB & FPB Base of proximal phalanx
& extensor expansion
Extension of thumb

10. 3. Tendon action
 Occurs in two joint or multi joint muscles
 Shortening of a tendon when antagonist muscle
contracts strongly
 E.g. weakness/ paralysis of long finger flexors
Trick movement Passive insufficiency Tendon action
Wrist extension Wrist flexors Finger flexion

11. 4. Rebound
 Phenomenon of seeming contraction in the
agonist when the antagonist contracts strongly &
the relaxes quickly
 E.g. weakness/ paralysis of long finger flexors
Antagonist contraction Trick movement
EPL & ED Finger flexion

12. 5. Gravity
 Patient will shift the body part so that gravity
assists the weak muscles to do the movement
 E.g. weak/ paralyzed triceps
Shifting of body part Trick movement
Shoulder abducted to 90° Shoulder depression & external
rotation

13. 6. Anomalous nerve supply
 20% of all normal people have anomalous nerve supply in
the hand
 These motor anomalies may/not be associated with an
anomaly of sensory supply and may not be bilateral or
symmetrical
 E.g. Median nerve palsy
Muscle action Anomalous innervation
Opponens pollicis, 2nd & 3rd
lumbricals, & FPB
Ulnar nerve

14. References
 Parry CBW. Trick Movements. Proceedings of the Royal
Society of Medicine. 1970;63(7):674-676
 Kendall, F. (2005). Muscle Testing & Function with Posture
& Pain (5th edition). Lippincott Williams & Wilkins.
 Avers, D. (2019). Daniels & Worthingham’s Muscle Testing,
Techniques of Manual Examination & performance Testing
(10th edition). Elsevier.

15. THANK YOU