A measurement device for measuring a change in the size and / or shape of at least a portion of an object having a surface, the device including: a first part for attachment to the object； a second part having a first portion moveable relative to a first portion of the first part； and a determining device for determining a displacement of the first portion of the second part relative to the first portion of the first part caused by the object changing, wherein the displacement is for use in measuring the change in the size and / or shape of the object.
