Excess hair on the elbows is called hypertrichosis cubiti while hair ears are known as hairy pinna
Information on hypertrichosis and hair removal treatments
Hairy Ears - Elbows
Excessive hairy ears known as “hairy pinna” and excessive
hairy elbows known as “hypertrichosis cubiti” are types
of localized congenital hypertrichosis.
Excessive congenital hair growth on the elbow region in a symmetric pattern is known as hypertrichosis cubiti or hairy elbows syndrome. The hair usually appears symmetrically at birth as lanugo hair, transforms into terminal hairs and becomes more pronounced in early childhood on the extensor surface of the elbow. The hair growth then usually regresses partially or fully in adolescence. Onset of hypertrichosis cubiti as late as at the age of 5 years has also been reported. More recently, the first case of hypertrichosis cubiti presenting excessive hair growth on the knees has been reported.
Biopsy of hair growth area shows normal dermal and epidermal structures. Endocrine and chromosomal studies have also shown normality in cases which were reported.
Hypertrichosis cubiti is familial and in some cases has been seen in patients with short stature, especially if other abnormalities are present as well. Out of the 22 cases of hypertrichosis cubiti, which were reported in one study, in 10 cases the patients were found to be of short stature. However, in several cases there were other coexisting conditions that adequately explained the short stature of the patients.
The mode of inheritance of this congenital hypertrichosis is not known. The reported cases give various inheritance modes, such as, autosomal dominant transmission with incomplete penetration, autosomal recessive transmission, or de novo mutation.
The association of hypertrichosis cubiti with facial asymmetry, developmental delay, ptosis with or without other focal areas of hypertrichosis and patchy unilateral hypertrichosis ipsilateral to the facial atrophy has been reported. It remains unclear whether these cases represent variants of this disorder or are an entirely distinct condition.
Some authors have hypothesized that the excess hair growth represents a nevoid abnormality, although its symmetry and consistent distribution have led others to conclude that it is simply the exaggeration of physiologic hair distribution.
This disorder, it is now believed, occurs more frequently than was earlier thought. In boys with dark hairs, excessive hair growths on the elbows sometimes may be a pure physiological feature and not a medical problem needing treatment. In others it is usually more a cosmetic problem than a medical one.
Hairy pinna (Congenital hairs on the external ears)
Excessive hair growth confined to the ears is a condition found usually in older men, although it has occasionally been found also in women. Congenital hair on the external ears is common among some of the populations of South Pacific, India and Sri Lanka. It is also found among some population groups in Europe, Africa and Australia. Some babies who have the XYY syndrome also exhibit such hairy growth on the ears. However, congenital hair on the pinna may be distinguishing mark of babies born to diabetic mothers, its presence independent of the degree of diabetic control. Excessive hair growth on the ears has also been found in patients with AIDS and diabetes.
The incidence of this disorder as reported will vary with the definition
of hairy pinna and on the population under observation. A definition of hairy
pinna has been given as one with at least several hairs on the top or side
of the ears and excluded hair around the external auditory meatus and lobe.
Using this definition, the incidence of hairy pinna is 26 percent in Israel,
50 percent in Madras in India and 10 percent in Bengal in India.