This categorization is important because large congenital melanocytic nevi are associated with an increased risk of melanoma, a serious type of skin cancer.Small: <1.5 cm
Medium: 1.5–19.9 cm
Large: ≥ 20 cm
Nevus of Ito
Nevus of Ota

Decreased melanin
Acquired
Nevus anemicus

Congenital
Nevus depigmentosus
		
Additional types of nevi do not involve disorders of pigmentation or melanocytes. These additional nevi represent hamartomatous proliferations of the epithelium, connective tissue, and vascular malformations. Epidermal nevi
These nevi represent excess growth of specific cells types found in the skin, including those that make up oil and sweat glands. Verrucous epidermal nevus
Nevus sebaceous
Nevus comedonicus
Eccrine nevus
Apocrine nevus

Connective tissue nevi
Connective tissue nevi represent abnormalities of collagen in the dermis, the deep layer of the skin. Collagenoma
Elastoma

Vascular nevi
These nevi represent excess growth of blood vessels, including capillaries. Nevus simplex (nevus flammeus nuchae), also known as a stork bite or salmon patch. Intramucosal nevi
An intramucosal nevus is a nevus within the mucosa as found in for example the mouth and genital areas. In the mouth, they are found most frequently on the hard palate. They are typically light brown and dome-shaped. Intramucosal nevi account for 64% of all reported case of oral nevi. Diagnosis
Nevi are typically diagnosed clinically with the naked eye or using dermatoscopy. More advanced imaging tests are available for distinguishing melanocytic nevi from melanoma, including computerized dermoscopy and image analysis. The management of nevi depends on the type of nevus and the degree of diagnostic uncertainty. Some nevi are known to be benign, and may simply be monitored over time.
The underlying problem, however, is not solved by wearing shoes with arch supports, or worsened by wearing shoes without arch support. There is currently no cure for the condition.In addition, people with ligamentous laxity often have clumsy or deliberate gaits, owing to the body having to overcompensate for the greater amount of energy required to offset the weakened ligaments. The feet may be spread apart at a wide angle, and the knees may flex backwards slightly after each stride. Those who have this disease may experience sprained ankles more frequently than other people. Cause
In most people, ligaments (which are the tissues that connect bones to each other) are naturally tight in such a way that the joints are restricted to normal ranges of motion. This creates normal joint stability. If muscular control does not compensate for ligamentous laxity, joint instability may result. The trait is almost certainly hereditary, and is usually something the affected person would just be aware of, rather than a serious medical condition. However, if there is widespread laxity of other connective tissue, then this may be a sign of Ehlers–Danlos syndrome. Ligamentous laxity may also result from injury, such as from a vehicle accident. It can result from whiplash and be overlooked for years by doctors who are not looking for it, despite the chronic pain that accompanies the resultant spinal instability. Ligamentous laxity will show up on an upright magnetic resonance imaging (MRI), the only kind of MRI that will show soft tissue damage.