synergies at the hand

Question 1

ABD of the fifth finger

Answer 1

FCU will contract along with the abd digiti minimi (ADM)

prevent simultaneous ulnar deviation, ABD pollicis longus (APL)

Question 2

thumb extension

Answer 2

as the extensor pollicis longus contracts

the extensor carpi ulnaris will contract to prevent radial deviation

Question 3

complete forceful thumb flexion

Answer 3

as thumb flexors (thenar group) contract

the palmaris longus contracts to tense the palmar fascia

to prevent wrist flexion, the extensor carpi radialis brevis will contract