Summary: Background: Localisation of the radial nerve (RN) in the spiral groove by previously reported methods has a wide range and is generalised. The objective of this study was to establish a method unique to a patient to accurately localise the nerve. Methods: The distance between RN at the midpoint of the spiral groove (D) and the tip of the olecranon (O) was compared with the most distal wrist flexion crease and fingertips on 100 healthy volunteers. The RN was found by ultrasound examination. Results: The mean distance from O to D was 16.22 cm (12.5–20.5 ± 1.55), and mean distances from wrist crease (WC) to second, third, fourth and fifth fingertips were 17.79 (14–20 ± 1.28), 18.66 (15–21 ± 1.32), 17.71 (14.5–20.5 ± 1.32) and 15.62 (12.5–20.5 ± 1.34) cm, respectively. With regards to O–D distance, the strongest relationship was obtained for the distance between the fifth fingertip to the WC (r = 0.708, p