Making a More Functional Hand

I have written numerous times in this blog about the importance of improving function for kids born with hand differences.  Function can be made better through therapy, through splinting, or through surgery. Whenever possible, we want to improve appearance as well.  There have been several investigations that found that kids born with hand differences are typically well adjusted, found HERE,  HERE,  and in our investigation to be published soon.  However, it is also clear that improving appearance is important to kids and families.  In a perfect intervention, we would improve both function and appearance.

There may be a times, thankfully not often, when improving function may come at a cost of some worsening of appearance.  If this is a possibility, frank discussions should be held with the family and many will eagerly proceed with an intervention for improved function.

This case is one example.  The child has symbrachydactyly, the cleft type (classification is reviewed in this POST).  He does well overall but has trouble grasping with the hand.

Symbrachydactyly, cleft type, palm view

Symbrachydactyly, cleft type, top view

Symbrachydactyly, cleft type, top view with thumb held

The thumb is of reasonable quality but the pinky is not greatly developed.  When we think of how to improve function in these situation, we need to lengthen the digits to allow the thumb and pinky the ability to pinch or grab.  There are three basic options:

1. Sometimes, lengthening a digit will make sense as described HERE.  But there must be sufficient bone present before we can lengthen.  

2. Other times, transferring a toe or toes to the hand will be the best option to improve function.  While this is a significant surgery for the patient and the whole family, it can be the best option to provide pinch and grasp in kids with few options related to limited anatomy.

3.  Lastly, and perhaps counterintuitively, we can deepen the space between the thumb and pinky.  This does not actually lengthen the digits but it makes them seem and act longer because bigger objects can be grasped.  Again, this may be considered different than some interventions because we usually try to get rid of the cleft, but in this case we deepen it.

This is the same patient after cleft deepening.

Palm view after cleft deepening.

For this particular patient, the seemingly small amount of deepening will (and has) make a notable difference for function.  And as he gets older, lengthening the bones can still be considered.

Functional improvements are always our goal in the care of kids with hand differences.  In this case, a small surgery should really help.

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

Skin Contracture and Z-plasty Correction

The field of hand surgery was developed around the time of World War II combining the fields of orthopedics (care of bones, joints, tendons, muscle), plastic surgery (care of skin, soft tissues, and nerves) and vascular surgery (care of blood vessels).  Given the very complex anatomy of the hand, wrist, and forearm, the concept of 'hand' surgeons trained with an anatomical focus in the upper extremity with expertise in the areas of orthopedics, plastic surgery, and vascular surgery makes a great deal of sense.  This 'new' field of hand surgery has grown dramatically in the last 60 years.

Skin tightness or contracture is a common finding in the care of children with birth differences.  The most serious skin deficit is syndactyly which, itself, varies in the degree.  Treatment of syndactyly has been a repeated topic of the blog, see posts HERE. 

Z- plasties are typically thought of as 'plastic' surgery procedures but in reality all hand surgeons, and especially those who treat kids, enjoy and utilize these procedures.

Tightness of the first webspace is seen in a number of different birth differences including the hypoplastic thumb, amniotic constriction band, simple or complex syndactyly, and symbrachydactyly.  Treatment varies based on the exact nature of the tight first web space, ranging from a large rotation flap (as described by Buck Gramcko) or z- plasties (skin lengthening through re- arrangement).

Z- plasties are used in any area of the body where there is a skin contracture.  The goal is simple: lengthen a tight band (no matter the cause).  There are different types of z- plasties including 2- flap, 4- flap, and 5- flap (or running man flap).  These flaps all lengthen the skin but with somewhat different benefits and challenges.  The simplest of these is the 2- flap z- plasty for the obvious reason that it only involved two flaps of skin.  These are typically designed at 60 degrees with each limb of equal length.  The four and five flap z-plasties are a bit more complex to design but those who favor these flaps believe they create a more natural appearance of the lengthening.  There is an excellent review of the basic 2 flap z- plasty HERE.

I will use different flaps including the 2 and the 5 flaps z- plasties most frequently.
Here is an example of the 2- flap z-plasty.

Tight first webspace in symbrachydactyly

First webspace after 2-flap z-plasty

Palm view of z- plasty after reconstruction.

This technique creates a nice deepening of the space which is critical to improving large object grasp. I enjoy this operation as it can dramatically improve function with a relatively straightforward surgery- few surgeries provide such a functional improvement.

Another technique is the 4- flap z-plasty.  While I don't want to get too technical, this flap can be created with either 90 or 120 degree basic flaps.  This figure provides an excellent explanation of the 120 degree 4- flap z- plasty.

This video from Bobby Chhabra shows this same concept in practice- Video Link.

 Finally, this image from the fastbleep.com website shows the 4 flap (both types) and 5 flap z- plasty.  The bottom image is the 5- flap z-plasty which is also called the "running man" which combines a 4- flap z-plasty and an advancement flap.

 I have used and will continue to each of these flaps.  Each can make a marked functional improvement for the patient.

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

Extra Digits: functional and social considerations

Today, children born with extra fingers or toes (polydactyly) are typically treated with excision and reconstruction of the hand or foot.  There are multiple reasons for the surgical approach.

First, the extra digit does not provide a functional advantage. The digits are rarely fully formed or fully functional.  Second, the extra digits can cause problems with daily activities.  The digits can get in the way of the other fingers as there may be deviation of the extra digit.  And, in addition, the extra digit can tether or cause deviation of the larger, more normal digit.  So the extra digit likely does not help function and may actually make it worse.

The extra toes cause the additional problem of interfering with shoe wear.  The extra toes widen the foot and can change loading patterns with walking or running.  While this can be addressed with especially wide shoes, removal of the extra toe may be a more straightforward solution.  Extra fingers cause a similar although less problematic issue- glove wear.  Clearly, wearing gloves may be a challenge or may not be possible with an extra digit.  However, given that in most places, shoes are typically worn and gloves are more optional, this is less of a problem for most patients.

Polydactyly of the feet with deviation of the extra toes.

There are also social considerations with the extra digits.  The extra digits certainly look different and may be noticeable in public.  Interestingly, a missing pinky is typically less noticeable than an extra pinky.  There have been multiple studies on appearance and hand differences.  One such study, whose lead author was Ann Nachemson, found that children with milder birth differences of the hand, such as patients with extra digits, had worse social interaction scores compared to more severely affected kids and 'normal' kids- see citation HERE.   Another study showed that overall health related quality of life measures in children with limb reduction deficiencies were better than kids with other health conditions.  However, 'unexpected attention and perceived physical appearance' affected scores.  Citation.

Recently, there have been a few newsworthy reports regarding extra digits in the ancient world.  The first is a white paper by Richard D. Barnett on "Polydactylism in the Ancient World".  This PAPER  reviews some interesting findings on polydactyly from centuries ago including the importance of which side was affected.  

In addition, there are recent findings from Chaco Canyon, New Mexico from Pueblo culture.  This National Geographic ARTICLE  reviews the findings.  "The findings, published today in American Antiquity, indicate that the society did not view six-toed individuals as supernatural, but this form of polydactyly did grant them exalted status in life and in death.  'We found that people with six toes, especially, were common and seemed to be associated with important ritual structures and high-status objects like turquoise,' says Crown, who is also a past National Geographic grantee."

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