Clinodactyly of the Fifth Finger

Genetics is a fascinating subject so far above my level of understanding it cannot be placed into words. As I have learned more about having Cowden Syndrome, I have learned more about signs indicating the condition and other genetic problems. I have seen things on myself and in my children that I did not understand to be connected to the syndrome.

The hand in the photograph is my own. For the most part, my hand looks normal but it is not. My hand demonstrates a phenomenon known as clinodactyly. Clinodactyly of the fifth finger (pinky) is a bending of the pinky toward the other four fingers.

I have always known the pinky on my left hand looked different from everyone else's pinkies. The top half of my pinky is entirely bent toward my other fingers. The top portion of the finger is small as if its growth were stunted and bent as though it belongs to an elderly lady with arthritis. My parents told me when I was one and one half years old I burned my finger by placing it in a Christmas light bulb that did not have the bulb. I assumed I burned this finger and it affected the growth. It wasn't until I looked at a letter written from my geneticist to my general physician that I realized there was a name for my odd pinky finger.

While I was incorrect about why my fifth finger is bent so awkwardly toward my other fingers, I was correct in assuming it was caused by abnormal development in the small bones of the finger.
Clinodactyly is fairly common but often associated with certain genetic disorders. In my case, the condition happens to come along with Cowden Syndrome but it is known to be associated with other syndromes as well. Russell-Silver syndrome, Feingold Syndrome, and Down Syndrome are each known to have this condition as a sign. If it is noticed on prenatal ultrasound it is considered enough of a risk factor for prenatal genetic testing of the fetus.

Some research indicates clinodactyly can be related to autism. An interesting personal experience with this is knowledge the PTEN gene mutation I have is also correlated with autism.
My daughter has been diagnosed with autism, Cowden Syndrome, and also has clinodactyly.

For many people, however, this fifth finger curvature goes unnoticed and is not related to a specific genetic problem. An estimated ten percent of the population has Clinodactyly though it is difficult to be precise in statistics because there is no set data on what constitutes the condition. More than one hundred causes of the condition have been discovered. To be confirmed as having clinodactyly usually an X-ray is performed of the hand.

Luckily no treatment is usually required for this condition. Surgery may be an option if the curvature worsens over time and interferes with hand function. If surgery is done, a cut is made in the bone to correct the deformity and the bones are stabilized until everything is well healed. Sadly recurrence can occur so most cases of fifth finger curvature are left without treatment.