Clinodactyly

Small finger clinodactyly with bending of the small finger towards the ring finger

Clinodactyly most commonly affects the small finger and causes a bending towards the ring finger through the middle phalanx.  However, clinodactyly can occur in any finger and often affects the thumb in children affected by syndromes (Downs syndrome, Aperts syndrome).  A complete listing of associated syndromes is beyond the scope of this review but more can be found at http://www.ncbi.nlm.nih.gov/omim

Unusual clinodactyly of the index finger.

The middle phalanx is typically the site of an abnormal growth plate.  The growth plate is usually only at the base of the finger bone but in this situation, there may be a growth plate around one side of the bone- a “bracketed epiphysis.”  This actually causes abnormal growth with one side growing more slowly, thus causing the curvature of the finger.  This typically worsens with age.

Clinodactyly xray with abnormal growth plate of middle phalanx, a “bracketed epiphysis.”  This leads to abnormal growth and worsening of the abnormality with time.

In most cases, clinodactyly is not severe and is most often an appearance issue rather than a function problem.  However, when severe or if particular activities are limited, surgery can be considered.  In young children, I prefer a simple procedure which divides the abnormal growth plate, thus correcting the tether from the bracketed epiphysis.  This procedure does not provide immediate correction but allows gradual correction with growth.  It is performed in younger kids, ideally less than age 5.  This concept is not new and an early description of this technique was provided by Caouette-Laberge, http://www.jhandsurg.org/article/S0363-5023(02)00014-X/abstract .

It is more common that clinodactyly becomes noticed or problematic in older children, past the age where this simple procedure is effective.  In those children, the bone can be cut and realigned (an osteotomy) with good results.  There are a number of different techniques with all providing similar good outcomes.  One issue after this surgery is stiffness affecting the last joint in the finger (the DIP joint).  This improves over time.  We reviewed these two basic procedures in the following article:
http://journals.lww.com/techhandsurg/Abstract/2010/03000/Surgical_Correction_of_Clinodactyly__Two.12.aspx

Here are a few clinical photographs of patients before and after surgery.   Patients and families are typically quite happy with the results of surgery.

Clinodactyly after correction on the left hand small finger and before correction on the right.

A different patient with clinodactyly correction on the one pinky but not yet on the other.