THE SIGNIFICANCE OF AN ABSENT ANKLE REFLEX

We assessed the prevalence of abnormal ankle reflexes in 1074 adult pa tients attending orthopaedic clinics and related it to age, Those with possible pathological causes of reflex loss were excluded. The absenc e of one or both reflexes was significantly related to increasing age; all patients under 30 years had both reflexes. Few had absent reflexe s between 30 and 40 years, but over 40 years, the proportion with both reflexes absent increased rapidly from 5% (40 to 50 years) to 80% (90 to 100 years), Unilateral absence did not show the same pattern of in crease being 3% to 5% at 40 to 60 years and 7% to 10% at over 60 years . Our results suggest that a significant number of 'normal' adults hav e unilateral absence of an ankle reflex, but this finding is rare enou gh to be a definite clinical sign, irrespective of age.