Abdominal pain is a common complaint, but when’s the last time you diagnosed someone with abdominal wall pain as the source of their presentation?
Carnett’s maneuver (aka the abdominal wall tenderness test) is an approach to diagnosing painful lesions in the abdominal wall, some of which can mimic peritonitis. In this exam maneuver, the clinician locates the area of maximal tenderness by gentle palpation and then applies enough pressure to elicit moderate tenderness. The patient is asked to lift the head and shoulders, as if performing a partial sit-up (alternatively, the patient may lift both legs off the table as a means of tensing the abdominal muscles). The test is positive if there is increased tenderness at the site of palpation, a finding that decreases the probability of peritonitis.
Interestingly, one notable cause of acute abdominal wall tenderness is diabetic neuropathy (i.e., thoracoabdominal neuropathy involving nerve roots T7 to T11; lesions of T1 to T6 actually cause chest pain). In addition to a positive Carnett’s maneuver, characteristic features of this disorder are cutaneous hypersensitivity (often in contiguous dermatomes) and weakness of the abdominal muscles causing ipsilateral bulging of the abdominal wall that resembles a hernia.