Thursday, September 26, 2013

Congenital Radial Head Dislocation

Congenital radial head dislocation is an unusual congenital anomaly of the elbow.  It is undoubtably present at birth but is rarely discovered until children get a bit older.  This is mainly because the limitations of radial head dislocation are not life- altering for most (including the motion limitations).  X- rays are usually the best way to discover a joint dislocation but may not be diagnostic in a young child.  Much of the elbow is cartilage in a young patient and the cartilaginous elbow is difficult to understand because cartilage is not visible on x- ray.  

So, congenital radial head dislocation often presents as children the reach an age of increased activities-   typically 4-8 years of age but often even older.  They usually complain of a lack of motion- specifically limited rotation of the forearm.  Rarely, elbow flexion or extension limitations may be noted.  Pain is rare in the younger patients but pain can be a problem in the teenager with a marked deformity .  When the dislocated radial head is bumped- it hurts.

Some basics.  First, children with congenital radial head dislocation have it for both elbows.  Second, it can be associated with syndromes- including nail- patella syndrome:  Others may include Klinefelters and Cornelia de Lange. Third, most dislocations are posterior or posterior- lateral but some may be anterior or truly lateral.  

One of the biggest issues with the diagnosis of congenital radial head dislocation is separating it from trauma causing a radial head dislocation.  It can be confusing.  There may be several tricks to separate the two. First, if both sides are involved, it is a birth (congenital) problem.  And second, the x- rays can help.  Typically the capitellum is rounded and the radial head is concave and round.  If these shapes are not present-  the radial head and capitellum have not developed normally because it is a problem present since birth (i.e., not a trauma).  Third, most radial head dislocations in kids are accompanied by an ulna fracture (Monteggia injury)- make sure ulna is ok!  And fourth, radial head dislocation may be a part of proximal radioulnar synostosis.  This is a different issue altogether.

In most cases, we do not surgically treat congenital radial head dislocations.  If discovered in a young child, there have been thoughts about putting it back in place but most believe this will not succeed.  In older kids, attempts to put radial head back in place are even less likely to succeed because the anatomy is altered.  So, given that most kids have few if any complaints- we do not recommend surgery.  However, in older kids, typically teenagers, pain can be an issue.  If the pain is a real issue, surgical excision of the radial head can be considered.  It should ideally be delayed until the growth plates are closed.  I have been very happy with our results with this operation but there are a couple of issues for families to consider.  First, the radius can move slightly proximally (away from wrist).  If it does, the ulna becomes prominent at the wrist and can be painful.  This can, in a small percentage of patients, require another surgery.  Second, we worry about the stability of the elbow and possibility of development of arthritis.  And third, excision of the radial head may improve elbow motion (best for rotation) but obviously does not make it normal.  We have published our results in this area with good outcomes:

Here are a few pictures of recent radial head excision in a teen with elbow pain.

AP x-ray of elbow with congenital radial head dislocation demonstrating deformity of radial head.  This teenager had pain.

Congenital radial head dislocation.  Not the head of the radius is out of place and misshapen.
The shape and appearance of the excised radial head.  The head should be round and completely covered in shiny, white cartilage.  This radial head in a 15 year old is arthritic and misshapen.  The separate piece of cartilage is also a problem- a loose body.

We take an x-ray of the wrist to understand the relationship of the radius and ulna before we remove the radial head.  This helps us understand issues later that might develop.

Friday, September 13, 2013

Short Fingers- Brachydactyly

I have written several times about symbrachydactyly- that is short, webbed fingers.  This common condition is distinctive in appearance (although there are multiple different types).   I have actually written 10 posts that relate to symbrachydactyly.

Brachydactyly, or short fingers, is a different condition as there are the normal 5 digits with shortening of either the phalanges or metacarpals or both.  The different classifications are helpful as there are so many types and the classifications help keep some sort of organization.  Most commonly cited are those by Bell and Temtamy and McKusick (Temtamy SA, McKusick VA. The Genetics of Hand Malformations. New York: Alan R Liss, INC; 1978).  There are a number of good educational sites on the topic of brachydactyly.  One such site is the OJRD- Orphanet Journal of Rare Disease which provides information through the NIH
and another great site is through OMIM- the Online Mendelian Inheritance in Man which categorizes each individual type.

I will not repeat all the detailed information available through these amazing sites.  A few key points, however, are worth repeating.  First, brachydactyly can be isolated or can be part of a larger syndrome.  This means that for most people, the short fingers are the only issue- there are not other conditions to worry about.  Second, it is most commonly passed in an autosomal dominant fashion (50% chance of passing it on to your children).  So, in most cases, a parent will have brachydactyly which obviously helps in understanding the abnormality.  And last, many of the genes associated with brachydactyly have been identified.  We actually know where the problem is in the human genome but, as of now, we can't do anything about it. Eventually, we may be able to "fix" the problem, but the science is simply not there yet.

Brachydactyly is typically a condition that affects the appearance of the hand more than the functional ability of the hand.  The type of brachydactyly obviously matters as some types will cause finger deviation, some an isolated shortness of the digits and some a combination.  The finger deviation is a type of clinodactyly as I have previously discussed.

Surgery is not usually required but can be helpful for marked deviation or, rarely, for marked shortening of the digits.  Surgery is usually an osteotomy (cutting of the bone).

This is an example of brachydactyly type E.  This patient had no pain, excellent motion (as shown), and was not overly concerned about the appearance of her hand.

Brachydactyly- both hands affected but the right hand is more noticeable.
Note the knuckle asymmetry in brachydactyly.
Brachydactyly with different length metacarpals.
The most notable finding in this patient with brachydactyly is the short 5th metacarpal. The 4th metacarpal is also short.
The right hand in the same patient with brachydactyly shows a very short 3rd and 5th metacarpal along with a short 4th metacarpal.

Sunday, September 1, 2013

Even More Thoughts on Pollicization

Pollicization is the surgical procedure in which the index finger (typically) is used to create a thumb.  It is most commonly performed for children born without a thumb or with a markedly small, unstable thumb but can also be performed in post- trauma situations in the adult.  The importance of a good thumb can not be overstated: first, it allows large object grasp (grabbing a soda can).  While one may be able to grab a soda can between the index and long finger, it is difficult as most of us do not have a big enough space to accomplish that goal.  The second reason that the thumb is so important is small object fine manipulation.  It is true that  one can manipulate beads or blocks between the index and long finger BUT, when you do so, you are using the sides of these two fingers which is a challenge.  It is much easier when one uses the pulpy part of the finger/ thumb to accomplish this goal.

So when the thumb is not suitable, the pollicization procedure is a great option because it really helps function.  There is an added benefit that it also really helps appearance as well.  A hand with a thumb (or pollicized digit) and 3 fingers looks almost normal and is almost never noticed as being abnormal.  However, a four fingered hand without a thumb is always noticed.

So, in case you can't tell, I (and others who share my passion for congenital hand surgery) really feel strongly that the pollicization procedure is a great operation for the right child (and family).  The risks are relatively low for such a procedure and the results are really predictable and good.  However, it is also an operation that is slightly different based on the surgeon.  Dr Manske, my former mentor and partner and a father of this field of surgery, published a "cookbook" of how to actually perform the procedure.  The 10- step process really does break it down nicely into straightforward steps.

But, the pollicization procedure, as much as any procedure I know in orthopaedic surgery, is really affected by the surgeon and the small decisions that the surgeon makes during the surgery.  We have written on some of the factors that affect the appearance outcome of pollicization

Some factors are out of the control of the surgeon and these factors include mobility (the most important factor affecting the outcome of the pollicization procedure is the quality/ mobility of the index finger), girth or size, nail width, among others.  However the surgeon can control some really important features including length, position of the web space, angulation (sometimes), mobility (to some degree), and perhaps most importantly, rotation.  None of these are easily controlled and, I believe, the decision- making comes with years of experience and lots of procedures performed.  It is why I believe that the best way to learn the entire field of congenital hand surgery is with a mentorship model- meaning that I feel that to be high quality congenital hand surgeon, one needs to learn from another very experienced congenital hand surgeon over time).  After all of my training (college, 4 years of medical school, 5 years of residency in orthopaedic surgery, and 1 year of fellowship in hand surgery), I had the pleasure/ honor of learning for another 10 years with Dr. Manske.  While I was certainly well- enough trained to perform the procedure immediately after I finished those years of training, I feel the extra years helped me immensely and helped to make me a better surgeon today.

My advice to parents considering this procedure is to understand the surgeon's training and the number of pollicization procedures that the surgeon performs each year.  He or she should be willing to share that information and if the topic is uncomfortable for discussion, to me, that is not ok.  Ask to see pictures of previous cases, talk to other patients, etc.

Here is a child after bilateral wrist procedures and pollicizations (1+ year out from last pollicization).  The left side, to me, looks wonderful and functions beautifully.  The right side works really well also but was more of a challenge as there was limited motion before surgery and so we made some decisions to help function at a slight cost of appearance.  The right side is rotation differently compared to the left and is a bit longer.  These are trade offs.  Mom and child are both very happy and he uses BOTH thumbs wonderfully.

Bilateral pollicization.  Left side is a bit more natural appearing due to decisions to maximize function on right.

Left side pollicization.

Left side pollicization demonstrating pinch.

Right side pollicization.  Thumb is slightly longer than usual to make up for decreased motion.

Left sided small block pinch after pollicization.

Left sided large block grasp after pollicization.