Pycnodysostosis is perhaps best recognised as the diagnosis given to Henri de Toulouse-Lautrec, a late nineteenth-century French artist.
Pycnodysostosis is a bone condition that is inherited. Its inheritance pattern follows the basic rules of genetics.
Short stature is a common symptom of pycnodysostosis. Adult males with the condition have a height of less than 150 cm (59 inches, or 4 feet 11 inches). Pycnodysostosis also affects adult females, making them even shorter.
Pycnodysostosis causes abnormally dense bones (osteosclerosis); the last bones of the fingers (the distal phalanges) are unusually short; and the normal closure of the connections (sutures) between the skull bones in infancy is delayed, resulting in the “soft spot” (the fontanel) on top of the head remaining wide open.
Pycnodysostosis is characterised by fragile bones that are easily broken (fractured). Leg and foot bones are prone to fracture. Fractures of the jaw and collar bones (clavicles) are also common.
What is the origin of the disease’s name?
The French physicians Maroteaux and Lamy established the name for this condition in 1962. In a study titled “La pycnodysostose,” they characterised the condition. (They weren’t the only ones who discovered the sickness.) In 1962, Andren and colleagues reported the syndrome separately.) Maroteaux and Lamy combined the Greek term “pyknos,” which means “dense,” with the composite word “dysostosis,” which means “abnormal bone development.” The term “pycnodysostosis” was coined to describe the disease’s characteristic abnormally dense bone.
Although Maroteaux and Lamy originally spelled it with a ‘c,’ it has been written with a ‘c’ or a ‘k’. The original spelling with a ‘c’ is used here. Regardless of how it is spelled, the word has remained and is now used to describe this condition all across the world. It is also simply called Toulouse Lautrec syndrome.
Pycnodysostosis’ exact frequency has never been identified. Pycnodysostosis belongs to a huge set of hereditary illnesses that are individually rare but collectively significant due to their sheer numbers, their devastating impact on affected individuals, and the equally devastating burden they inflict on their families.
What are some of the symptoms of pycnodysostosis?
Small stature, dense brittle bones, short fingers, and the wide-open soft spot of the skull are all symptoms of Pycnodysostosis (see above). The head and face, teeth, collar bones, skin, and nails are among the various anomalies. The head’s front and back are prominent. Many tiny bones may be seen within the open sutures of the skull (called wormian bones). The midface isn’t as full as it usually is. The nose stands out. It is possible for the jaw to be tiny. The palate is grooved and thin. Baby teeth are slow to emerge and maybe lost much later than expected. Permanent teeth can sometimes take a long time to appear. Permanent teeth are frequently irregular, and some teeth are missing (hypodontia). The collar bones are frequently deformed and undeveloped. The skin on the backs of the fingers is wrinkled and saggy. The nails are grooved and flat.
Pycnodysostosis might also produce issues that become apparent over time. Aside from shattered bones, the distal phalanges (the final bones of the fingers) and the collar bone might deteriorate with time. Vertebral abnormalities can cause the spine to curve to the side (resulting in scoliosis). Tooth problems frequently necessitate orthodontic treatment, and dental cavities are widespread.