Wednesday, April 9, 2014

Symphalangism (stiff fingers)

Symphalangism is a rare birth anomaly of the fingers which literally means: joined bones.  Most commonly, it refers to an ankylosis (bony union) or fibrous tissue union of the finger bones preventing finger motion.  It can be nonhereditary or it can be hereditary.   Nonhereditary symphalangism occurs without known family history.  It can be associated with other nonhereditary conditions such as Aperts or Polands syndrome.  Sometimes the fingers can be short as well as stiff.

There are two main types of hereditary symphalangism: SYM1 (Cushing Symphalangism; OMIM #185800) which is stiffness of the PIP joints, the wrist and ankles and deafness.  It is passed in an autosomal dominant fashion (50% chance of passing it on) and has been localized on the genome at 17q22.  SYM1  There is also a SYM1b (OMIM #615298) has been localized to chromosomal 20q11 and relates to a defect in the GDF5 gene.  SYM1b

The other inherited type of symphalangism is SYM2 (Distal Symphalangism, OMIM %185700).  This includes stiffness of the DIP joints of the hands and feet.  Less is known about this condition but it is also autosomal dominant.  SYM2

Traditionally, attempts to surgically improve finger motion in symphalangism have had limited results.  However, recently, Baek, et al reported reliably improved motion with surgical release.  They also felt surgery in younger children may be more successful.  Baek paper

Patients with symphalangism present with a stiff finger (or more than one, finger or toe).  On examination, the stiff joint will not have the normal skin creases on the top or bottom.  X-rays may appear similar to the normal fingers but often the two bones are fused on x-ray so that there is no joint.

Here is one example of a child with symphalangism and a single, stiff joint.

Middle finger (long finger) symphalangism.  Note the lack of skin creases over the PIP joint.

Symphalangism.  Note the lack of finger flexion of the middle finger at the PIP joint.

The x- rays in symbrachydactyly look normal without clear evidence of the abnormality.











8 comments:

  1. I believe both of my boys have symphalangism and a single stiff joint. I had asked my children's doctor about their middle fingers and how they looked different than they should. The doctor seemed unconcerned and said it was something we could x-ray later in life. My sons' fingers look just like the fingers in the photo above of the small child. My older child has this on both hands and my younger child only seems to have it on one hand. No one in my family seems to have this condition, but both my boys do. My older child in 3.5 years old and the other is just 1 month old. I am concerned about the other conditions that can go along with this. How would I know if they have one of the conditions that can go along with this? My older son had hypospadias, which was corrected with surgery, and also is having issues with his eyes (crossed eyes, lazy eye)... are any of these conditions known to be connected with symphalangism? Since my children's pediatrician doesn't seem to be knowable on this topic I would love to hear from someone who is? Should I find a specialist of some kind and have my children seen by this person? If so, what kind of specialist should I see? What kinds of other things should I be looking for in my children to know if there are other related health issues going on with them? I can email you pictures of my children's fingers if you provide me a way to contact you. Thank You so much for your time!

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    1. Mandy, thank you for your comments and question. We know that symphalangism can be passed along in an autosomal dominant way and so both kids having it makes sense. We know that there are very few associated conditions- this link highlights the genetic suspected cause- the noggin protein: http://ghr.nlm.nih.gov/gene/NOG. I also understand that hearing loss can be associated. Questions
      1) A geneticist might be helpful. Their expertise will obviously depend on their experience but someone at a Childrens Hospital is typically somewhat knowledgable and can research the issue further.
      2) Again, there are no major associated conditions to my knowledge other than other stiff joints
      3) If I can help more, feel free to email at congenitalhand@wudosis.wustl.edu

      Thank you.

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  2. My has 4 fingers on each hand with thumbs being normal. His father only has the fifth digit affected. Im concerned with him playing sports a risk of injury. Or even impaired circulation. His hand's are freezing. Color is normal. He is perfectly capable of writing, typing, and even trying to play a guitar.

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    1. Jennifer,

      Thank you for the comment. In my experience, sports and other activities are safe. I am not sure why his hands are cold- does it vary based on the weather? Finally, I am glad to hear that he can participate in perform the listed activities- this is what really matters and most kids and adults function normally (they just might do things slightly differently).

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  3. My daughter is 16 and suffering from this condition. She really wants to be a surgeon when she grows up and so the use of her hands is very important to her. Her hands work just fine now, but they are constantly stiff and sore. Is it possible for her to have her hands operated on at this age, even though the article said that the outcome was best in younger patients? And if so, do you have a name of a doctor that could perform this surgery?

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    1. Kathryn,

      Thank you for your question. Surgery to restore joint motion in symphalangism is difficult even in a young child and I do not think possible in older patients such as you daughter. However, occasionally, there may be surgeries to put fingers in better functional positions which can both help function and decrease symptoms. This is difficult to clarify further as it depends on which joints, which fingers, etc. An experienced hand surgeon (ideally one with experience in birth differences) can likely give you advice. Good luck!

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  4. My daughter is 4 weeks old and we have noticed she is unable and to flex (passively and actively) all of her PIP joints on both hands. I am suspicious she may have this. How early do you recommend surgical intervention if she is a candidate?

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    1. Kayti,
      Thank you for the question and sorry for my delay. If you have a hand surgeon who specializes in this condition, it would make sense to seek intervention early. The one report by Baek reported surgery a bit older than I would prefer, 46 months on average. Earlier surgery allows earlier remodeling and I have operated at closer to one year of age. Better motion can make a difference to function. If I can answer more specific questions, feel free to email at congenitalhand@wudosis.wustl.edu

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