<prompt> Which of the following movements of thumb are not affected in radial nerve injury:OppositionFlexionAdductionAll  <response>: A i.e. Opposition; C i.e. Adduction; B i.e. Flexion Posterior interosseous branch of radial nerve supplies extensor pollicis longus brevis EPL EPB and abductor pollicis longus AbPLQ 3 thumb muscles. So radial nerve injury weakens affects abduction extension movements of thumb and spares flexion, adduction oppositionQ Movements of Thumb Movements Extension Flexion Abduction Adduction Opposition Muscle - Extensor pollicis longus - Flexor pollicis longus FPL - Abductor pollicis - Aductor pollicis - Opponens EPL PIN M longus AbPL AdPU pollicis OP M Nerve - Extensor pollicis brevis - Flexor pollicis brevis PIN - ls, dorsal - Flexor pollicis EPB PIN - Abductor pollicis longus FPBM U - Opponens pollicis OP M - Abductor pollicis brevis AbPBM interosseous U brevis M U AbPL PIN PIN posterior interosseous nerve br of radial nerve; M Median U Ulnar nerve Flexor pollicis brevis has dual nerve supply i.e. superficial head from median and deep hed from ulnar nerve. 