Beevor's sign.

Introduction

Beevor's sign in clinical neurology refers to the abnormal upward movement of the umbilicus on attempting to raise the head from a supine position by the patient being assessed. Charles Edward Beevor described it as follows: “When a patient sits up or raises the head from a recumbent position, the umbilicus is displaced toward the head. This is the result of paralysis of the inferior portion of the rectus abdominal muscle, so that the upper fibers predominate pulling upwards the umbilicus.”[1] Classical teaching emphasizes the observation that in normal individuals, the umbilicus is observed unchanged in its position when one attempts to raise the head from a resting supine position.

Anatomy

The rectus abdominis is one the anterior abdominal muscles that acts to keep the viscera in its location within the abdomen. Contraction of the rectus abdominis aids the evacuation of the rectum, urinary bladder and the uterus. It is a sheet-like muscle supplied by the ventral rami of the lower six or seven thoracic nerves. The fact that the umbilical position normally remains unchanged, i.e. in its central location during the contraction of this muscle, implies that it contracts as a single unit. Weakness of the lower divisions of the rectus abdominis results in the upward movement of the umbilicus on contracting the muscle. This is called the Beevor's sign. Figures 1 and 2 shows the differences in the development of upper and lower abdominal rectii in a patient with positive Beevor's sign. The uncommon occurrence of the downward movement of the umbilicus due to weakness of the upper divisions of the rectus abdominis could be called the inverted Beevor's sign.[2]

Figure 1

Normal appearance of abdominal muscles on CT scanning

Figure 2

Atrophic infraumbilical portion of rectus abdominis

Discussion

A positive Beevor's sign is commonly observed in fascioscapulohumeral muscular dystrophy. In one study, it was observed in 27 of 30 such patients, but was not observed in 40 patients with other neuromuscular disorders.[1] In these patients, the genetic diagnosis was not available as the gene was not identified then. A subsequent study, done in 2005, identified Beevor's sign in 19 of 20 patients with a genetic confirmation of fascioscapulohumeral dystrophy, supporting the earlier study, but also found it to be positive in only two of 28 in the non-fascioscapulohumeral dystrophy group.[3] These two in the non-fascioscapulohumeral group were patients with familial tubular aggregate myopathy. Charles Edward Beevor first documented the finding of upward deflection of the umbilicus on flexion of the neck in spinal cord injuries at or below the level of T9.[4] An acute Beevor's sign has been described in a single patient with spinal cord infarction extending from the T10 to the T12 levels.[5] The other neuromuscular condition in which Beevor's sign may be observed is amyotrophic lateral sclerosis.

Charles Edward Beevor (1854–1908) had a distinguished neurological career and, at one time, was President of the Neurological Society of United Kingdom. With another neurologist, Armand de Wattville, he described the exaggerated jaw jerk reflex in 1885 in a woman with amyotrophic lateral sclerosis.