Nailfold Capillaroscopy of Fingers and Toes - Variations of Normal.

BACKGROUND: Nailfold capillaroscopy is the only method for morphological assessment of nutritive capillaries. The literature data about capillaroscopic findings in healthy individuals are scarce.

OBJECTIVE: To evaluate and compare the capillaroscopic findings of fingers and toes in healthy subjects.

MATERIALS AND METHODS: 22 healthy individuals were included in the study. Capillaroscopic examination was performed with videocapillaroscope Videocap 3.0 (DS Medica). Exclusion criteria were as follows: history of vasospasm, presence of accompanying diseases, taking any medications, arterial hypertension in first degree relatives, overweight or obesity (body mass index > 25kg/m2) and presence of chronic arterial or venous insufficiency.

RESULTS: Poor visibility of nailfold capillaries was found significantly more frequently in the toes (22.7%, 5/22) as compared with fingers (0/22). Slight irregularities in capillary distribution and orientation to their parallel axis were significantly more common in the toes (31.8%, 7/22) as compared with fingers (9%, 2/22), (p<0.05). The mean diameter of the arterial (0.012±0.002mm) and the venous limb (0.017±0.002mm) of the toes did not differ significantly as compared to the respective parameters in the fingers (0.013±0.002mm for the arterial limb, p=0.46 and 0.018±0.002mm for the venous limb, p=0.25). The mean capillary density also did not differ significantly in the fingers and toes. The mean capillary length of the toes (0.165±0.096mm) was shorter as compared with hands (0.220±0.079mm), but the difference was not statistically significant (p=0.37). Presence of tortuous capillaries (>10%) was found significantly more often in the toes (12/22) as compared with fingers (6/22, χ2=6.769, p<0.05). Short capillary loops (length<100µm) were observed significantly more often in the toes (11/22 - toes, 1/22 - fingers, χ2=14.666, p<0.05).

CONCLUSION: Capillaroscopic examination of the toes shows some differences as compared to those of the fingers such as greater number of cases with poor visibility and slight irregularities of distribution, greater number of shorter capillaries and increased tortuosity, which might be related to the thicker epidermis of the toes and increased capillary pressure due to gravity. The values of the major capillaroscopic parameters such as capillary diameters and capillary density in fingers and toes do not differ significantly.