A retractor having an elongate portion with first and second parts each with adjacent pivotally connected segments pivotable from a first configuration to a second configuration, wherein in the second configurations the adjacent segments abut each other to inhibit further movement, at least one of the parts including a control whereby a force required to move the first part from the first configuration towards the second configuration is less than the force required to move the second part from the first configuration towards the second configuration, and an actuator arranged to urge the first and second parts from the first to the second configurations at the same time.
