An instrument for extracting a pin from a substrate, such as a bone mass, which comprises a first lever arm with a body part having a channel in which a free end of a pin can be received, a second lever arm which can pivot relative to the first lever arm, a gripping member within the body part by which the pin can be gripped to retain the pin in the channel, and a terminating member mounted on the body part having an end face and two side walls which extend along opposite sides of the body part. The terminating member has a slot provided in a portion of the end face and which extends along a portion of at least one of the two side walls configured to guide the free end of the pin into the instrument prior to being received into the channel.
