The authors' excellent observation that being driven over bumps in the road will aggravate the pain of localised peritonitis is very well taken. They correctly ascribe this phenomenon to rebound tenderness. This reminds me of my methods of eliciting rebound tenderness in the clinical scenario, having had to modify the traditional method for eliciting the sign, due to far too many raised eyebrows during a process that is guaranteed to make the patient at the very least wince in pain.

May I suggest the following techniques instead: If pain is exacerbated on pumping up the bed for examination, then rebound tenderness is present. Naturally, motorised beds cannot reproduce the same effect. Additionally, pumping up the bed to height is an essential step, and a far milder way to flex the inflamed peritoneum. In children, an excellent and often humorous way to achieve the same is to gently shake the child from side to side with one hand on each side of the pelvis.

If both of these methods fail, then percussing over the affected area, or McBurney's point in acute appendicitis, is a more direct, but still a gentler method of eliciting the sign of rebound (percussion) tenderness, which is indicative of underlying localised peritonitis.

Competing interests: None declared