The slipping slipper sign: a marker of severe peripheral diabetic neuropathy and foot sepsis

Peripheral neuropathy is a major contributor to diabetic foot complications including ulceration, sepsis and limb loss. The aim of this study was to document the frequency of this previously undocumented clinical marker of peripheral neuropathy, the "slipping slipper sign" (SSS), characterised by unrecognised loss of slippers from one's feet while walking, and to compare it with traditional clinical tests for peripheral neuropathy.

To evaluate the relationship between a positive SSS and diabetic peripheral neuropathy.

The study included 105 diabetic outpatients without active foot problems, 40 diabetic inpatients with active foot sepsis, and 69 other patients with neither diabetes nor active foot sepsis as negative controls. Demographic data, clinical neuropathy scores and the presence or absence of the SSS were obtained.

No control subjects had a positive SSS. In contrast, 64 of 145 diabetic patients had severe neuropathy of whom 53 had a positive SSS (83% sensitivity) and 74 of 81 without severe neuropathy had a negative SSS (91% specificity). Diabetic patients with concurrent foot sepsis had a higher frequency of severe neuropathy (70%) and positive SSS (65%) compared with those without (36% and 35%, respectively, p<0.001). Multivariate analysis showed that a positive SSS was strongly related to severity of neuropathy independent of duration of diabetes.

The SSS reflects severe peripheral neuropathy and is particularly prevalent among those with active foot disease. Patients who have experienced the SSS should be encouraged to seek attention and preventive action taken.