Saturday, June 16, 2018

Families, Choices, and Untreated Triphalangeal Thumbs

One of the benefits to my taking care of kids with birth anomalies of the upper extremity is the opportunity to really come to know the patient and the family, often over many years.  This is magnified when more than one child is affected.  This is one of the best things about my practice (and one of the limitations of the other parts of my practice)- that is treating a patient and family over years.  I really enjoy watching kids grow, learning about their development, and understanding how their birth anomaly does or does not affect their lives.

Another interesting opportunity is talking to and understanding the experience of an affected parent.  This is critically important because the experience of the affected parent influences their goals and hopes for their child.  It also usually moderates their concerns.  What I mean by this is that most parents who are also affected understand that their child is likely to be highly functional and also likely to be well adjusted

Kids with birth anomalies never cease to amaze us and it takes time for 'new' or unaffected parents to realize just how well their child will do and how many expectations will be exceeded.  Affected parents simply better understand their child's status and have appropriate expectations for the future.  

One particular family has become particularly special to me as I have come to know the whole family and done so over many years.   Mom and the kids have triphalangeal thumbs together with an extra thumb.  Mom's triphalangeal thumbs were untreated (although the extra thumbs were removed when she was a child) and she understands the diagnosis and its implications very well.  We have performed surgery on her kids due, at least in part, to mom's understanding of how surgery would be helpful.

A few features to take note of.  
1) The thumbs are long.  This is due to the extra bone in each of the thumbs (triphalangeal- 3 phalanges instead of the normal thumb with 2 phalangers).  
2) The thumbs appear thin, almost like a finger.  
3) The thumbs do not rest in the normal position.  The thumbs are more in the plane of the fingers- some might call this a 5 fingered hand rather than a hand with 4 fingers and a thumb.

Adult with triphalangeal thumbs.

Adult with triphalangeal thumbs, palm side

Adult with triphalangeal thumbs, thumb flexion.  Note the length.

Adult with triphalangeal thumbs. Note that the thumbs are in the plane of the fingers.

Adult with triphalangeal thumbs, right
Adult with triphalangeal thumb, left























Nonetheless, the patient has very good function.  There are a few challenges with fine motor skills and pinch.  This video shows thumb motion and gives a sense of function.






A few relevant blog posts:

The bottom line is that patients with a triphalangeal thumb function well with or without surgery.  However, surgery does offer improved function and appearance as confirmed by this family and the choices they have made.

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








Sunday, June 10, 2018

Three thumbs

Radial polydactyly (duplicated thumb) is an uncommon condition in the general population- I have blogged about kids with extra thumbs a number of times.  Those posts can be found HERE.  Extra thumbs come in a wide variety of patterns, some of which are captured in the Flatt Classification (previously called the Wassel Classification) as shown in the this picture from orthobullets.com.
Flatt Classification for radial polydactyly from orthobullets.com


Yet, this classification does not capture the extra thumbs in all kids with radial polydactyly.  Many simply do not fit this pattern.  As a result, the Rotterdam (in the Netherlands) group added a more complex classification system which is much more comprehensive.  The publication abstract can be found HERE.  It includes more specific patterns for triphalangeal thumbs (longer thumbs, more like a finger), triplicate thumbs (three thumbs, rather than the more common 2 thumbs), as well as adjustments for stiffness, deviation, and small size). 

This is one example of a triplicate thumb.  These are uncommon (even compared to the uncommon radial polydactyly). 
Triplicate thumb

Triplicate thumb, another view

Final view of triplicate thumb

And here are a few x- rays which show the complexity.  This is a complex arrangement of bones and joints.
Triplicate thumb xrays

Additional xrays for triplicate thumb

The principles for treating the triplicate thumb are to create a stable, well aligned thumb.  The thumb's main role is to serve as a post and if stable and well- aligned, it can do just that.  Ideally, we would love to have motion at the joints but motion is not mandatory for a great thumb.  So, in reconstructing these three thumbs- the goal is to create the best single thumb.  This requires excision of some parts, straightening of some bones, stabilizing joints (with new ligaments), and careful treatment of the skin and soft tissues (cosmetic surgery).

Here are images at about 3 months after surgery for the triplicate thumb. The child is starting to use his new thumb and will, over time, use it more and more.  The thumb is stable.  It is reasonably straight although not perfect.  And he does have some motion.  It may be that he will benefit from additional surgery down the road.  If so, we try to perform that second surgery before kindergarden.  Such surgery is needed in approximately 1/3 typical radial polydactyly patients but in notably more triplicate thumb patients like this one.

Top view of thumb after reconstruction for triplicate thumb

Palm view after triplicate thumb reconstruction



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