Tuesday, October 30, 2012

Central Deficiency with 2-3 fingers

Central deficiency (cleft hand) is classically as I have shown in previous blogs.  http://congenitalhand.wustl.edu/2012/05/cleft-hand-surgery.html We have previously published our experience with the classic central deficiency, that is the hand with a limited thumb- index web space, 3 fingers (index, ring, and small finger), and a large cleft http://www.ncbi.nlm.nih.gov/pubmed/18984341

However, there are many different varieties of cleft hand, as previously classified by Dr Ogino in Japan and Dr. Manske here in St. Louis.  Dr Ogino's classification is based on how many digits are missing and Dr Manske's classification, http://www.ncbi.nlm.nih.gov/pubmed/7594304  is based on the thumb web space- which is important for function.  If the thumb- index web space is limited, the overall hand function will be markedly limited.  The child will struggle to grab large objects but also will find it difficult to manipulate smaller ones.

With less common types of central deficiency, surgery is sometimes completely avoided or may be minimized.  Consider these 2 examples.

A conjoined thumb with pinky finger in cleft hand.  Note the small web space.

Cleft hand with difficulty grasping large objects.  The thumb is not positioned to best grasp or pinched (i.e., not opposed to fingers)

Cleft hand xray.

We will likely help this child's function with 2 procedures, one to slightly deepen the web space to allow larger object grasp and a second to rotate and reposition the thumb in a position to better pinch and grasp against the pinky finger.

2) Consider the next child with a very similar hand.  A merged thumb and a single other digit.  However, the difference is that the cleft is deeper allowing the child to grasp larger objects and the thumb is opposed.  Look how the child can grasp with the thumb against the finger with a pen and with cheerios.  Surgery is unlikely to help.  Additionally, one might consider narrowing the thumb but I would argue against that procedure as I think it would hurt function and would be unlikely to help appearance.

A second child with similar cleft hand.

Cleft hand with a well- opposed thumb easily manipulating a pen.

Also able to easily manipulate a cheerio.  Note the position of the thumb against small finger.

Wednesday, October 24, 2012


Hemihypertrophy is a difficult diagnosis due to its rarity and the variety of associated conditions.  Basically, the diagnosis means that one extremity (or one side of the body) is enlarged compared to the other side.  As little as a 5% difference can be diagnostic but usually families seek care when the difference is more notable.  It can be dramatic.  As a hand and upper extremity surgeon, I typically see kids with one arm or one part of the hand which is larger than the other.  There is some information on the web which is useful including this website: http://hemisupport.com  The most commonly associated conditions are listed below (and there are others as well); not all patients will have a syndrome but we do assess for the following conditions.  I have only briefly summarized these conditions with links for more information.

Beckwith- Wiedemman syndrome is one possible diagnosis and its diagnosis is important to make because of possible associated tumors.  http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002168/

Proteus syndrome is an overgrowth condition affecting skin, bones, soft tissues, and other organs.  It may be asymmetrical.  This condition is exceedingly rare (1 in 1,000,000) and is related to a genetic abnormality (not inherited).  http://ghr.nlm.nih.gov/condition/proteus-syndrome

Klippel- Trenaunay Weber Syndrome.  KTW is characterized by port wine stains on the skin, extra bone and soft tissue growth, and varicose veins.  Classically associated with vascular malformations.   http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001205/

Neurofibromatosis is a condition with numerous nerve tumors which may grow rapidly.  Type 1 is more common and is associated with cafe au lait spots on the skin.  http://www.ninds.nih.gov/disorders/neurofibromatosis/neurofibromatosis.htm

 The orthopaedic surgeon or pediatrician often makes the diagnosis of hemihypertrophy but a geneticist is usually involved for full evaluation of the possible associations.  My role in hemihypertrophy is to provide information, refer families to geneticists and other providers, help make the appropriate diagnosis, and arrange referral or testing to rule out the rarely associated tumors (such as Wilms tumor).  Surgery for hemihypertrophy can sometimes be helpful to control growth (by limiting the growth plates) or to debulk enlarged areas.  Sometimes amputations are the best course of action.  Surgery is a difficult decision as our options are not ideal and the effectiveness of surgery is also limited.

One example of hemihypertrophy

Sunday, October 21, 2012

Too much about me

I have been asked on several occasions by patients (or prospective patients) to provide more information on the blog about my professional career.  Enclosed, please find a variety of links including local and regional publications and videos.  I have included links to several books and articles.

First, my basic bio from Washington University

1) Great Story on a Child born in Central America with 3 arms

2) Peer Reviewed Publications as of October 6, 2012

3) Links to Published Books
- Hand and Upper Extremity Therapy: Congenital, Pediatric and Adolescent Patients.  Saint Louis Protocols.

- A Pocketbook Manual of Hand and Upper Extremity Surgery: Primus Manus

- Tendon Transfer Surgery of the Upper Extremity: A Master Skills Publication

4) St Louis Medical News

5) Ladue News

6) St Louis Children's Hospital Trauma Services Interview

7) St Louis Children's Hospital Doctors Digest on Trauma

8) Best Doctors in America, 2007-2012

9) American Society for Surgery of the Hand (ASSH) Board of Directors (Council)

Severe Ulnar Deficiency

Ulnar deficiency, as described in a previous post has characteristic findings at the elbow, forearm, and hand.  http://congenitalhand.wustl.edu/2011/09/ulnar-longitudinal-deficiency-basics.html

Most classifications describe 4 types of ulnar deficiency (or ulnar longitudinal deficiency- ULD).  These classifications only address the bony deficiency (and not the important other issues such as muscles, tendons, nerves, etc).  While there are a number of classifications, the basic description is as follows:

Type I is a slightly short ulna
Type II is a notably short ulna
Type III is an absent ulna
Type IV is a completely absent ulna with fusion of the radius and the humerus.

We have helped to extend the classification in both directions.  When the ulna is normal and there are only abnormalities of the hand (such as metacarpal synostosis, absent digits, etc) , this can be described as a Type 0 ulnar deficiencyhttp://www.ncbi.nlm.nih.gov/pubmed/16344190

On the other end of the spectrum, some kids have a severely shortened extremity.  Traditionally, these children have been classified as having a phocomelia.  Phocomelia (which will be the topic of another post) technically implies a segmental deficiency in which, for example the hand is attached to the arm (i.e., humerus) without a forearm.  However, in another investigation we were able to demonstrate that most kids with a diagnosis of phocomelia actually have a diagnosis of either radial deficiency or ulnar deficiency: http://www.ncbi.nlm.nih.gov/pubmed?term=ezaki%20goldfarb%20manske

The importance of making the correct diagnosis cannot be understated, most importantly for 2 reasons: the genetics related to the diagnosis and the associated conditions.  The genetics of a particular diagnosis will allow for information regarding the risks that the parents should understand for having another child with the same diagnosis and also the risk that the patient will someday have a child with the same diagnosis.  The other issue is associated conditions.  Some diagnoses carry a risk for associated conditions such as a heart or kidney problem whereas others do not.  Therefore, making the correct diagnosis allows the ideal medical evaluation of the patient.

Here is an example of severe ulnar deficiency, or Type 5 ulnar deficiency.  Note the short extremity and the three conjoined fingers.

Ulnar deficiency on right

Another view of ulnar deficiency

Note the 3 fingers with syndactyly in ulnar deficiency

Radiograph of ulnar deficiency.  There is one bone which has a split (kind of like a wishbone).  There is no separate radius and ulna.

Saturday, October 6, 2012

Severe Symbrachydactyly and Nubbins

Symbrachydactyly, as noted previously, http://congenitalhand.wustl.edu/2011/12/normal.html  means "short, webbed fingers."  The use of this label is clearly appropriate for some children who (brace yourself for this truth) have short and webbed fingers (i.e., a syndactyly).  The term symbrachydactyly has further meaning as it has implications for etiology (i.e., cause).

I believe symbrachydactyly occurs due to difficulties with the AER and the underlying mesoderm during development- please see previous description of limb development http://congenitalhand.wustl.edu/2012/10/limb-formation.html  If the AER is lost, limb outgrowth stops and there is a deficient limb.  The theory is that early loss (i.e., at 4-5 weeks of gestation) leads to a really short limb and later loss (i.e., at 6-7 weeks of gestation) leads to more subtle symbrachydactyly.  The following children would be considered to have a severe symbrachyactyly- at least the way I consider it.  We have shared our thoughts and experiences with this diagnosis in the Journal of Hand Surgery: http://www.ncbi.nlm.nih.gov/pubmed/17996776

Nubbins of symbrachydactyly

Another example of severe symbrachydactyly
The "nubbins" on the end of the arm likely represent some remnant from the cells from development (from the apical ectodermal ridge).  The nubbins can be surprisingly well formed and often have fingernails.  Some families preserve and value the nubbins while others feel that the nubbins get in the way and can be difficult to keep clean.  When families request, the nubbins can be easily excised with a small surgery.  The nubbins certainly do not grow and removal, therefore, is reasonable because function of the nubbins will not get better with age.  I leave these decisions to the family.

Others believe severe symbrachydactyly really should be called a transverse arrest or congenital amputation of the limb.  I don't mind those terms but I happen to believe this is most likely a development issue (a malformation)- meaning that something went wrong during limb development, not after.

The above examples differ from less severe symbrachydactyly:
Short finger type of symbrachydactyly- short, webbed fingers.

Another short finger symbrachydactyly

Limb Formation

I have been remiss in that I have not given an overview of limb formation.  Mind you, this is  a topic that is constantly changing- we learn more each year about the process, the proteins, the timing, etc.  So this is a hand surgeon's perspective in 2012.  There are others with a much better understanding of limb development- people who continue to add to our understanding.  I have enjoyed getting to know Kerby Oberg from Loma Linda, one of those people.  He is a vital part of a congenital hand surgery study group as well.  http://www.llu.edu/medicine/basic-sciences/faculty/anatomy/oberg-kerby.page

The upper limb forms from about 28 days of gestation to about 56 days of gestation- that's right from 4 to 8 weeks of gestation. Many women may not even be aware of pregnancy at that time.  By the 8 week point, the arm and hand are in an amazingly, fully formed state.  There are fingers, a thumb, and joint with a big- picture normal appearance.

So, how do we get there?

The limbs start to form based on signaling mechanisms, genes, and proteins (and everything is about genes, signaling and proteins).  TBX-5 and TBX- 4 are genes that help "turn- on" upper and lower limb formation respectively.  The upper limb is about 2 days ahead of the lower limb.  HOX genes play a role as well.  There are three axes that guide limb development: proximal/ distal, anterior/ posterior, and dorsal/ ventral.

If you imagine that the developing limb is a blob of cells, the center of the blob is mesodermal cells and the outer layer is ectodermal cells.  The complex interaction between these cells guides development of the arm.  The outer layer is called apical ectodermal ridge (AER for short) and it continually interacts with the inner cells of the mesoderm.  Fibroblast growth factors (FGFs) are the key to this interaction.  But importantly, the AER guides limb growth or lengthening.  If you take away the AER, the limb stops growing.

The other key area is on the back side (post axial) of the limb and is termed the zone of polarizing activity (ZPA).  The ZPA interacts with the AER and the developing limb to help determine the development of the different parts- specifically thumb side of limb (radial side) versus pinky side of limb (ulnar side).  This is based on a morphogen called sonic hedgehog (which can be abbreviated Shh).  (lab humor= the name 'sonic hedgehog').  This protein affects development of the fingers, thumb, etc.  Some really amazing experiments showed that if you take the ZPA (or even the sonic hedgehog) and add it to the other side of the developing limb, you can develop a "mirror" limb as more fingers develop.  This is described beautifully in one of my favorite articles: http://genepath.med.harvard.edu/~tabin/Pdfs/Riddle.pdf

This is a mirror hand with 8 fingers.  We believe this happens due to problems or duplication of the ZPA.
And the ZPA interacts with the AER constantly as the limb develops.  Check out the simple drawing (from 12 years ago!) which emphasizes this interaction:

Complex interaction between ZPA and AER, simplified.


Finally, Wnt 7a and Lmx-1 help determine the top and bottom of the limb and fingers (ie nail side of finger vs palm side).

I will refer back to this blog on limb development as it relates to anomalies.