It is a genetic disorder that results in small, poorly developed nails and kneecaps.it can can also affect many other areas of the body( elbows, chest, and hips)

Cause

This is a genetic disease.

Symptoms

Improper development of the fingernails and toenails, underdevelopment of certain bones and/or webbing of skin at the bend of the elbow, absence and/or underdevelopment of the knee caps , and/or abnormal projections of bone from the upper portion of both sides of the hipbone .