This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nerve Injuries - 1, Subject name: Orthopaedics
Given video shows findings of an abnormality. The patient has most likely suffered lesion at which level? 
Select and explain. 
A. Radial groove, B. Lower 1/3 of forearm, C. Neck of radius, D. At wrist
A: Radial groove
Answer: A: Radial groove 
Explanation: Low Radial nerve palsy: Injury is before the spiral groove. All muscles supplied by radial nerve are paralysed. Low radial nerve injuries may be of two types:- 1) Type 1: Injury occurs between the spiral groove and elbow joint. Muscles involved is:- Elbow extensors(Triceps,Anconeus) are spared. Wrist, elbow and finger extensors are paralysed. Sensory loss in first web space(on dorsal side). 2)Type 2:-Injury occurs below the elbow joint. Elbow extensors,brachioradialis and wrist extensors(ECRL)are spared. Finger extensors (extensor digitorum,extensor digiti minimi,extensor indicis),ECRB and thumb extensors(extensor pollicis longus & brevis)are paralysed. Sensory loss in the first web space(on dorsal side).