All of the following are affected in low radial nerve palsy except -
In type II low radial nerve palsy ECRL, triceps, Anconeus, and brachioradialis are spared.

Clinical features of radial nerve palsy


Clinical features depend upon the site of the lesion.

1) 1f lesion is high

Wrist drop, thumb drop and finger drop.
Inability to extend elbow, wrist, thumb & fingers (MP joint)
The patient can extend interphalangeal joints due to the action of lubricants and interossei.
Sensory loss over posterior surface of arm & forearm and lower lateral half of forearm.

2) If the lesion is low
a) Type I


Wrist drop, thumb drop and finger drop.
Elbow extension is preserved.
Sensory loss over the dorsum of first web space.

b) Type II

Thumb drop and finger drop
Elbow and wrist extension is preserved
Sensory loss over the dorsum of first web space

Clinical features of posterior interosseous nerve

It is prone to be injured in injury & operations of radial head- neck .
There is no sensory deficit as it is a pure motor nerve.
Wrist extension is preserved (i.e. no wrist drop) due to spared extensor carpi radialis longus .
Presents with loss of extension of metacarpophalangeal (MP) joints i.e., thumb & finger drop.
Extensor carpi radialis longus
Extensor carpi radialis brevis
Finger extensors
Sensation on dorsum of hand