Ridged nails

Symptoms and Signs, Chapter 65

Longitudinal ridges in the nails are generally due to Liver-Blood deficiency or Liver-Yin deficiency.

Indented nails

Symptoms and Signs, Chapter 65

Nails take about 150–180 days to grow and horizontal indentations may appear in the course of a serious disease. From the location of a horizontal indentation, we can therefore gauge roughly the time of onset of the disease. Figure 15.1 illustrates two nails in section with two indentations corresponding to two different times of onset of a disease, one roughly 120 days, the other approximately 30 days.

Apart from indicating the onset of a disease, in general terms indentations of the nails may be due to deficiency and dryness of Liver-Blood, general deficiency of Qi and Blood, or Heat injuring fluids. Moreover, small indentations of the nails are also seen in chronic skin diseases such as eczema and psoriasis, in which case the clinical significance is different, simply indicating chronic Liver-Blood deficiency.

Thin and brittle nails

Symptoms and Signs, Chapter 65

Thin and brittle nails generally indicate Qi and Blood deficiency, and particularly Liver-Blood deficiency. In severe cases, they may also indicate a deficiency of Kidney-Essence.

Thickening of the nails

Symptoms and Signs, Chapter 65

Thickening of the nails may be due to Liver-Fire, Liver-Blood stasis, or Phlegm.

Coarse and thick nails

Symptoms and Signs, Chapter 65

Coarse and thick nails generally indicate Qi and Blood deficiency with Blood-Dryness generating Wind, which often happens in chronic psoriasis. In some cases, coarse and thick nails may indicate accumulation of Dampness.

Withered and brittle nails

Symptoms and Signs, Chapter 65

Withered and brittle nails are generally due to a deficiency of Liver-Blood or Liver-Yin. In some cases, they may also be due to Liver-Blood stasis, in which case the withering of the nails is caused not by a lack of nourishment of Liver-Blood but by stagnant Liver-Blood being unable to reach the nails.

In some cases, Liver-Fire may cause the nails to become withered and brittle. If this occurs and the nails look scaly, it indicates a severe Kidney deficiency.

Withered and brittle nails in some cases may be due to Phlegm in the joints and this is seen in cases of chronic Painful Obstruction Syndrome with Phlegm, in patients suffering from rheumatoid arthritis. The withering of the nails observed in psoriasis is usually due to either deficiency and Dryness of Liver-Blood or stasis of Liver-Blood.

In acute cases, withered nails may appear in the aftermath of a febrile disease resulting in Blood- and Yin-deficiency with Blood-Dryness and Empty-Heat.