Outcome after Surgery for an Extra Thumb

The condition of a child born with two thumbs has many, many names but most commonly, we call it radial polydactyly, thumb duplication, or split thumb.  While all are utilized, radial polydactyly is the medical term and split thumb is appropriate as both thumbs are smaller than the other thumb.  I have posted about radial polydactyly previously as can be seen HERE.

We have learned over the years that surgical reconstruction of the extra thumb is much more than removing one of the thumbs.  The remaining thumb requires stabilization and often straightening. This can be tricky and, I believe, is best accomplished by a surgeon with experience in treating these problems- really the more experience, the better.  Even then, sometimes a second surgery may be required as the child ages.  This has been discussed over the years but a nice long term follow- up study from Dallas, as detailed HERE, reports on 43 kids at an average follow- up of 17 years.  These late surgeries were for different reasons but a crooked thumb was often the issue.

The surgical goals for radial polydactyly are to

1) Remove the extra thumb

2) Maintain the 'better' thumb.  Typically that is the one closer to the hand but not always

3) Stabilize the thumb (i.e., make sure the ligaments are good)

4) Align the thumb (i.e., make sure the bones are straight)

We typically add a temporary metal pin to protect the surgery during the first 5 weeks when the child is casted.  Cast and pin are removed at the first visit after surgery.

Here is an example of the early outcome after reconstructive surgery for radial polydactyly.  This child was not as complex as some but still a challenge.  One thumb was clearly larger and it was also crooked, requiring straightening of the bone at the time of surgery.  Both the family and I are pleased at this point but we will follow the child over time to assure that the thumb stays straight and functional.

Radial polydactyly before surgery.  Note that the large thumb is somewhat crooked.  

Here is the side view of the thumb after surgery for radial polydactyly.  Not the subtle scar.

Top view of the thumb after radial polydactyly reconstruction.  The thumb is straight.

Charles A. Goldfarb, MD
My Bio at Washington University
congenitalhand@wudosis.wustl.edu

Multiple Hereditary Exostosis- Its Not Always about the X-rays

Multiple hereditary exostosis is an uncommon tumorous condition and is capable of causing significant functional limitations.  I have previously posted on MHE.  While multiple hereditary exostosis in the fingers can cause deformity and limitations of finger flexion (I need to post on this topic), we worry more about the forearm.  The problem is that if the two bones of the forearm don't grow at the same rate, the natural rotation of the forearm may be lost.

However, when the bones don't grow at the same rate, the best techniques for surgical correction in multiple hereditary exostosis is not clear.  Multiple techniques have been described including lengthening the short ulna, correcting angulation of the radius, or 'detethering' (separation) of the radius and ulna growth.  There is no question that these techniques each have a role and make conceptual sense.  And all may allow the x-rays to look better.  But none have shown to clearly improve motion in patients with multiple hereditary exostosis.

And, to make things more confusing- even patients with dramatic findings on x-ray can do very well functionally.  The case below in a 12 year old with multiple hereditary exostosis proves this point. She has no pain, great motion, and no interest in surgery.  Time will determine if her outstanding function continues.

Multiple hereditary exostosis.  Note the radial head dislocation on the left.

Multiple hereditary exostosis.  Great forearm supination.

Multiple hereditary exostosis.  Very good but not perfect forearm rotation on both sides.

Multiple hereditary exostosis.  Right radial head is out of position.

Multiple hereditary exostosis.  Right radial head is dislocated.

Left elbow with radial head dislocation (with great motion and function). In multiple hereditary exostosis.

Right elbow with radial head dislocation although not as notable as the left (with great motion and function). In multiple hereditary exostosis.

Charles A. Goldfarb, MD
My Bio at Washington University
congenitalhand@wudosis.wustl.edu

Pollicization- concerns immediately after surgery

Pollicization, or the creation of a thumb, is a fantastic procedure that creates a hand that is more functional and looks better.  It is certainly a specialized procedure in that most hand surgeons don't perform this surgery.  I do believe that this is a surgery that is best performed by surgeons that do at least several of these each year.  If this is the case, the surgeon is familiar with the procedure, the specific tricks and tips in performing the surgery, and understands what to worry about.  That is, the problems that can happen around the time of surgery and the problems that can appear months or years later.  I have blogged several times about pollicization- read here. 

Here is a recent surgery on pollicization.  This case is interesting to me because the child has a thumb- but it is a really small thumb that is completely unstable (i.e., floppy) and a thumb that she does not use.  In the US, most of congenital hand surgeons agree that this thumb is best treated with a pollicization (in Asia, some surgeons will stabilize this thumb).  However, this is a tough conversation for the family (it is easier to discuss a pollicization when there is no thumb).

Hypoplastic thumb Type 3B

Second view of a hypoplastic thumb, type 3B

Successful pollicization

Second view of successful pollicization

So this child did well in surgery and just after surgery.  The color of the thumb was good.  We carefully watch kids in the recovery room and also typically overnight in the hospital.  We want to make sure the thumb does not turn white (which means not enough blood flow in) or purple (which means that there is not enough blood flow out).  In this case, all looked good.

Mom called 3 days later to say that she was concerned about the color of the thumb and we asked her to bring the patient in to be seen.  The thumb did look slightly darker but not dramatically so.  We loosened the dressing and it looked somewhat better.  

Pollicization position and color of the thumb.

Slightly dark thumb after pollicization.

We elected to continue to carefully watch the patient.  Rarely, in the situation when thumb clearly does not look healthy, a return trip to the operating room is required.  In my experience, that has only very, very rarely been necessary and it has been immediately after pollicization.

Charles A. Goldfarb, MD
My Bio at Washington University
congenitalhand@wudosis.wustl.edu