Monday, July 5, 2021

Syndactyly, Macrodactyly, and Keloid

The treatment of syndactyly is highly successful, no matter the preferred technique. That is the classic technique of Flatt (dorsal commissure flap and zig- zag incisions- ) or graftless techninques or hyalomatrix- all can work. Complications include web creep (maybe not a true complication as it is so commonly seen), wound healing issues, rare infections, etc. Hypertrophic scarring is very, very uncommon. However, with macrodactyly there is a risk of keloid formation. While we do not understand this, it is likely related to PIK3CA . While macrodactyly may be dramatic, it can also be subtle and bears the surgeon's close attention. Here is one view of a patient's syndactyly and a few surgeries immediately after surgery.
The family chose to work with dermatology and that decision has worked out very well, now more than 2 years out from surgery. Silicone sheeting and applying a topical corticosteroid, clobetesol propionate usp 0.5%, has led to dramatic improvement in the keloid.
These are very difficult decisions and, needless to say, I am pleased this has worked out well. The use of methotrexate is not new (> 40 year history) for keloid but the attention to this treatment option was raised by Ezaki (As noted above) and by Tonkin. The excellent outcome here will likely influence my decision for treatment options in patients who delveop keloid after syndactyly reconstruction. But, the other important question is around patients who with macrodactyly and syndactyly- should we always use methotrexate in those patients at the time of the syndactyly reconstruction? Thanks for reading, Charles A. Goldfarb, MD My Bio at Washington University email: congenitalhand@wustl.edu Please CLICK HERE to support our research. Designate my name. Thank you!

Saturday, April 3, 2021

Understanding the 'Why' of Upper Extremity Birth Differences Part 1

Birth differences of the upper extremity have many different forms/ presentations. These can be a dramatic with a shortened or deviated extremity or very subtle/ mild with slightly short fingers or a subtle lack of muscle development. In my three decades of caring for kids, it has always been clear that our team is truly caring for the whole family. Families have many questions about what we can do to help their child (surgery, therapy, what the future holds for their child, and the 'why'- why is their chiild, their family affected with this anomaly. The purpose of this blog post is to discuss the last issue, the 'why' of birth differences of the upper extremity. This is part 1 and I will add a part 2 with some specific information about different anomalies. I always share with patients that limb differences are most commonly related to errors to our genetic code- the DNA. This means that there are changes (mutations) in the DNA sequences related to errors in the coding. We believe that some of these are random (just happen), some are clearly a genetic condition (passed from parent to child), and some are caused by external causes that lead to the mutation. This can be related to medication, environment, or other causes of DNA changes. To me, the fact that our bodies get it 'right' as often as they do is really remarkable. I stress that in the vast majority of patients, nothing a parent did caused the mutation in the DNA and nothing they could have done would have prevented this error. This is really, really important because all parents question their "role". Known examples of medications or drugs causing a limb difference are really uncommon. The most striking and perhaps the most understood example of a medication leading to an extremity difference is the drug thalidomide which was given in the 1950s and early 1960s to help prevent nausea of pregnancy. Thalidomide caused dramatic "phocomelia" or limb shortening. I have blogged about this before on several occasions: This is a classic image from Smithsonian magazine.
Our understanding of birth differences continues to grow but it is safe to say that we all want to know more. The first step in understanding why birth differences happen is understanding what normal (or maybe I should say typical) limb development looks like. We know that upper limb development occurs from 26-54 days of gestation- with the upper limb fully formed before the end of the second month of pregnancy (although obviously quite small). There are three axes of development each with each being guided by different proteins, signals, and morphogens. The axes all development and progress simultaneously and NOT independently- there is a complex interaction between these areas. 1) The proximal distal axis 2) The anterior posterior axis (also known as the radial- ulnar axis and the pre-axial- post axial axis) 3) The dorsal- volar axis (top and bottom of the limb and fingers) One of my favorite articles on limb development was written more than 20 years ago and it discusses one of the key morphogens- sonic hedgehog. Robert Riddle and Clifford Tabin share insights which have stood the test of time including the importance of this video game inspired name of a key protein.
There have been many experiments to better understand limb development and some of my favorites use chick embryos. The developing limb can be easily altered to assess the impact of different proteins or areas of the developing limb. Cheryl Tickle has made notable contributions in this field as higlighted . Below I share a few images from my friend and limb development expert Kerby Oberg. Kerby has made so many contributions to the field is a close friend to clinicians who focus on the treatment of kids with limb differences. He is also a part of the team that created the very important and practical classification system for upper limb anomalies- the OMT. We recently updated the classification system as part of a great team.
The proximal distal axis This axis of development is all about the limb growing longer and bigger. The apical ectodermal ridge (AER) is the key area of ectoderm that interacts with the underlying mesoderm to grow the limb. This limb is affected dramatically by TBX5, Wnt3, FGF8 and FGF10.
The anterior posterior axis This axis is guided by sonic hedgehog (as noted above). This protein diffuses across the developing limb and is key for ulnar sided limb development. Too little contributes to ulnar deficiency and extra (especially in a different area) can lead to a mirror hand. Radial deficiency is likely more related to Gli3 but this is a complicated interchange.
The dorsal ventral axis This axis is least well understood and, perhaps, least 'important' to limb development. Classically, we think about LMXb1 as driving the difference in function and appearance between the top and bottom of the fingers.
My next post will be more on what we know about specific conditions and what might go wrong during limb development. Thanks for reading, Charles A. Goldfarb, MD My Bio at Washington University email: congenitalhand@wustl.edu Please CLICK HERE to support our research. Designate my name. Thank you!

Saturday, February 6, 2021

Forearm Synostosis- Facts and My Approach to Treatment

 I have previously blogged about forearm synostosis HERE.  A few important points

1) It uncommon compared to other upper extremity anomalies but is perhaps the most common of the forearm birth differences.

2) It is really well tolerated by most children.  Especially because the rest of the upper extremity is typically normal (most importantly, the hand)

3) The function impact depends on a few factors:

The position of the forearm (i.e., how rotated is it)

Whether one arm or both

The child- each child is affected differently

4) It is recognized later than many birth anomalies because it is not immediately obvious. 

It is a bony problem and the forearm can look normal.  Parents often count fingers and toes but, unless the parent is a congenital hand surgeon, parents do not typically test forearm rotation. 

Each of us can "rotate" through our wrists so that it looks like the forearm is rotating.  Unless you actually feel feel the forearm, determining rotation can be tough.

Functional limitations may be few and often do not become obvious until the child is required to perform higher- order tasks (often school age or sports).


When is surgery helpful?

Surgery is not typically required but a few factors increase the likelihood of surgery being helpful.  First, when both forearms are affected it is more difficult for the child to compensate.  And second, when the forearm is fixed in severe rotation (typically palm down/ pronation but can be palm up/ supination).


What is the 'best' surgery?

There are two basic concepts for surgery (and only one works).  

1) The most appealing to every single parent and every single surgeon- restore rotation of the forearm.  That is, take out the bony block and allow the radius and ulna to rotate the forearm.  There have been a huge number of techniques attempted but I want to be clear: these surgeries do not work

2) Position the forearm in a more neutral posture (think clapping position).  This allows shoulder motion to help position the hand and is a highly effective surgery.  This requires cutting and repositioning the bones.  There are two techniques

a) I believe more surgeons are using a technique to cut the bone at the site of the bony fusion (the           synostosis).  This works but, in my opinion, has a few challenges.  

        It requires metal pins for approximately 6 weeks while the bone is healing.  Pins can                             sometimes cause problems.  Pins are typically removed in the office but occasionally in the                operating room.

        Like every surgery, there can be complications. 

b) A two- stage procedure called osteoclasis.  I like and use this procedure with younger kids.  Each stage is straightforward.  In the first stage, the bones are cut but not moved.  This limits the nature of the surgery and the risks.  In the second stage, the bones are rotated to the desired position and casted.  Healing almost always occurs by 6 weeks.  The negative of this surgery is the fact that it is 2 stages but there are many advantages for the right child and the right family. 


Here is a great example.  The four x-rays capture the deformity and the joining of the bones (again, the formal name is synostosis) near the elbow.  

Forearm synostosis.  Arrow points to the bony joining bw radius and ulna.

Forearm synostosis.  Arrow points to the bony joining bw radius and ulna.

This young patient was treated with a two- stage osteoclasis procedure.  Below are a few pictures marking the incisions and the initial x-rays for the first stage.  The incisions are quite small (< 1 inch).  

Marked (two dots) planned incision for osteoclasis procedure in which the radius bone is cut

Marked (two dots) planned incision for osteoclasis procedure in which the ulna bone is cut

After cutting the radius and ulna for forearm synostosis

After cutting the radius and ulna for forearm synostosis


There is not much to share after the second stage (rotation of forearm to the desired position).  You might wonder- why not do all in one stage?  This is a great question with two answers.  Delaying the rotation decreases complications and helps to maintain the new position b/c the bone are 'sticky' as they start to heal.  That is why no metal (pins) are required.


Thanks for reading,


Charles A. Goldfarb, MD              

email: congenitalhand@wustl.edu

Please CLICK HERE to support our research.  
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Sunday, December 13, 2020

2 Reasons for Less than 5 Fingers

 A brief post with lots of pictures and videos on two conditions that may cause less than five fingers.  As I have previously written, there are 5 common causes.  Parents have given permission.


Diagnosis 1.  Symbrachydactyly.  This patient has a great thumb and nubbins past the metacarpals.  However function is excellent.  The child will likely favor the normal opposite extremity.

Symbrachydactyly with great thumb

Palm view of symbrachydactyly with great thumb

Effective grasp in patient with symbrachydactyly



Diagnosis 2.  Cleft hand.  This patient has severe cleft hand (and cleft feet) but functions amazingly well.  Both hands are the same.

Bilateral severe cleft hand, single digit

Cleft hand patient demonstrating function

Radiograph of severe cleft hand, single digit.




These videos are excellent in showing function.  The first video shows finger motion and the second shows writing without aids.  The others show the benefits of adaptive devices.










 

Saturday, October 31, 2020

2 Common Types of an Uncommon Condition- Symbrachydactyly

When I consider all of the different patients with a birth anomalies that I have the privilege to evaluate and treat, there is no question that symbrachydactyly is the diagnosis most often misnamed or unnamed.  Amniotic constriction band is perhaps most commonly given as the incorrect diagnosis for the patients.

Symbrachydactyly literally means short, webbed fingers.  And that certainly can be how patients with symbrachydactyly present as I have previously shared here- Previous Post.  While there are 7 types (depending on your favorite classification), in my mind there are two types which are most common.  All seven seem to be related to the same issue, and not a genetic one.  We believe that a lack of blood supply to the developing limb is most likely the cause of symbrachydactyly and the timing determines the severity, the type.

The short finger type of symbrachydactyly is really the type that best fits with the name.  The fingers are shortened due to a short or absent middle phalanx and the fingers are also commonly webbed.  The other common type is the "cleft" type symbrachydactyly in which the thumb and little finger are normal or close to normal and the index, middle, and ring fingers are notably short and may be only a nubbin.


Here are two great examples of these two types of symbrachydactyly.  First, the short finger type.  This patient had surgery to separate the fingers at about 18 months of age and is functioning at a high level and is satisfied with appearance.

Short finger symbrachydactyly.  Note the middle phalanx is abnormal. 

Short finger symbrachydactyly.  Close examination shows the surgical scars from web deepening.

Short finger symbrachydactyly.  


The other common type of symbrachydactyly is the cleft type.  The painted fingernails help visualization.  And the nubbins are small bones (distal phalanx) with nails that develop from the ectoderm after the vascular insult affects the mesoderm in the developing arm.



Cleft type symbrachydactyly.  Note the three nubbins in the cleft. 

Cleft type symbrachydactyly.  Note the thumb is normal and the little finger is more, but not normally developed as the middle phalanx is absent.


Thanks for reading,


Charles A. Goldfarb, MD              

email: congenitalhand@wustl.edu

Please CLICK HERE to support our research.  
Designate my name.  Thank you!




Saturday, October 31, 2020

2 Common Types of an Uncommon Condition- Symbrachydactyly

When I consider all of the different patients with a birth anomalies that I have the privilege to evaluate and treat, there is no question that symbrachydactyly is the diagnosis most often misnamed or unnamed.  Amniotic constriction band is perhaps most commonly given as the incorrect diagnosis for the patients.

Symbrachydactyly literally means short, webbed fingers.  And that certainly can be how patients with symbrachydactyly present as I have previously shared here- Previous Post.  While there are 7 types (depending on your favorite classification), in my mind there are two types which are most common.  All seven seem to be related to the same issue, and not a genetic one.  We believe that a lack of blood supply to the developing limb is most likely the cause of symbrachydactyly and the timing determines the severity, the type.

The short finger type of symbrachydactyly is really the type that best fits with the name.  The fingers are shortened due to a short or absent middle phalanx and the fingers are also commonly webbed.  The other common type is the "cleft" type symbrachydactyly in which the thumb and little finger are normal or close to normal and the index, middle, and ring fingers are notably short and may be only a nubbin.


Here are two great examples of these two types of symbrachydactyly.  First, the short finger type.  This patient had surgery to separate the fingers at about 18 months of age and is functioning at a high level and is satisfied with appearance.

Short finger symbrachydactyly.  Note the middle phalanx is abnormal. 

Short finger symbrachydactyly.  Close examination shows the surgical scars from web deepening.

Short finger symbrachydactyly.  


The other common type of symbrachydactyly is the cleft type.  The painted fingernails help visualization.  And the nubbins are small bones (distal phalanx) with nails that develop from the ectoderm after the vascular insult affects the mesoderm in the developing arm.



Cleft type symbrachydactyly.  Note the three nubbins in the cleft. 

Cleft type symbrachydactyly.  Note the thumb is normal and the little finger is more, but not normally developed as the middle phalanx is absent.


Thanks for reading,


Charles A. Goldfarb, MD              

email: congenitalhand@wustl.edu

Please CLICK HERE to support our research.  
Designate my name.  Thank you!



Saturday, October 17, 2020

An Unusual Pollicization Procedure

Radial polydactlyly (extra thumb) is a relatively common problem for those of us who treat kids with birth differences/ anomalies of the upper extremity.  Please see the following link for previous posts on the topic LINK.  Sometimes these can be treated by a "straightforward" procedure with excision of the extra thumb and stabilization of the primary thumb.  Other times a more complex surgery is required which can include a similar procedure + cutting and realigning the bones.  More rarely, other procedures are required.  This is one such case.  

This patient has an uncommon type of extra thumb.  There are really two issues.  First, there are really two extra thumbs.  And second, there are five fingers (including the most radial one being in the plane of the fingers).  



Unusual radial polydactyly (extra thumb)
Another view of Unusual radial polydactyly (extra thumb)



X-ray showing the extra thumb (or 2 thumbs) with 5 fingers.


Initially, we made a decision with the family to remove the extra thumbs.  Structurally, there is no 'great' thumb and creating a useful thumb would be difficulty if not impossible.  Instead, we focused on removing these thumbs and then better understanding if a second surgery would be necessary.  There was a possibility that the patient would be sufficiently function with a five finger hand.

Here is the hand after the first surgery.

View after surgery.  Now a 5- finger hand

5- finger hand after surgery 


Ultimately, we decided that additional surgery made sense for function primarily but also appearance.  This is a triphalangeal thumb that is largely in the plane of the fingers making pinch a challenge.  There are different approaches but we elected to perform the pollicization procedure and are pleased with the early results.


After pollicization surgery, 4 week visit


Another view after pollicization surgery


Another view after pollicization surgery




I believe that his new thumb to function really well.  It takes time for kids to start using the new thumb although each child is different- some start using it well at 3-4 weeks and for others, it can take 6 or more months.  Therapy is helpful, sometimes with simple actions like taping the thumb in an easy, functional position and other times with more deliberate functional assistance.

Thanks for reading,


Charles A. Goldfarb, MD              

email: congenitalhand@wustl.edu

Please CLICK HERE to support our research.  
Designate my name.  Thank you!



Saturday, October 3, 2020

Early Action in Madelungs Deformity

Years ago, I met an 7 year young lady who came to my office with no complaints.  Mom brought her even though she had no hand or wrist pain and no functional limitations.  The reason for the visit was a strong family history of Madelungs deformity (mom and sister).  There was no clinical evidence of a syndrome and the patient was of normal height.  However, xrays did confirm very early, quite subtle Madelungs deformity of both wrists.

First, most of the time we do not have the opportunity to see patients so early.  The typical patient with Madelungs deformity presents at 11- 12 years of age with wrist deformity and perhaps some motion limits and pain.  Occasionally, a happenstance xray (maybe for a trauma) will pick this up or, as in this patient, a family history will lead a family to bring a younger brother or sister in for evaluation.   The classic example is a patient with Leri Weill dyschondrosteosis which includes Madelungs deformity, short stature, and short forearms (a form of dwarfism).   These patients have a more obvious clinical presentation and have a known genetic issue with the SHOX gene as noted in this link.  Another great site is OMIM.  

Second, the question of etiology is not completely clear.  We know that the distal radius growth plate (a specific part- ulnar and palmar) does not grow as it should.   This is likely the primary issue.  The role of a ligament tether is less clear.  This was first discussed by Dr. Vickers in Australia and we typically call the abnormal ligament by his name- the Vickers Ligament.  This structure is really a thickened short radiolunate ligament (a normal structure).  Whether this ligament is a cause of the radius deformity in Madelungs deformity by acting as a tether or whether it is a secondary effect is unclear.  However, there is some evidence that release of this ligament might be helpful.  This report is helpful and there is much anecdotal evidence as well.




This article describes a small group of patients treated with an open excision of the ligament without progression of the deformity.  My personal experience is mixed.  Sometimes this can work, other times it has not been successful.  Nonetheless, because this operation is straightforward, safe, and allows a fast recovery, it makes sense for many families as it offers the chance to avoid the bigger operations often required as seen here: Madelungs Surgery

The other option is an arthroscopic release of this ligament- this further simplifies the operation, the scarring, and the recovery.  We can release the short radiolunate ligament through this minimally invasive approach through pokehole incisions that disappear.

This patient was seen as a 7- year old.  There were subtle xray changes as you can see here.


Early Madelungs deformity of the left wrist, findings from 2015  


In some cases, the xrays are normal.  MRI can be helpful in these situations to assess the growth plate and a potentially abnormal short radiolunate ligment (Vickers ligament when it is thickened/ abnormal). 

The now 12 year old patient returned for a check up without complaint.  She is now 5 years after her small surgery.  No pain, no deformity.  Radiographs continue to show mild Madelungs.  We will continue to follow this patient for 2 additional years while her growth plates are open.





Thanks for reading,


Charles A. Goldfarb, MD              

email: congenitalhand@wustl.edu

Please CLICK HERE to support our research.  
Designate my name.  Thank you!