Radial Deficiency Small Thumb

Form and Function in Radial Deficiency

There are a variety of factors which affect appearance and function in patients with radial deficiency (RLD).  Some of the major factors to consider include (not necessarily in order as it will vary from patient to patient):

Factors affecting appearance                                       Factors affecting function
1) Radial Deviation                                                     1) Length of forearm
2) Short length of forearm                                           2) Finger motion/ function
3) Presence/ status of thumb                                        3) Presence/ status of thumb

Other factors should be considered as well but I think these are less important.  These include forearm motion- rotation (lacking especially in those with severe RLD) and wrist motion (generally limited and tending towards flexion with a lack of extension).

Some of these may be addressed with surgery although none are completely correctable.
1) Radial deviation (which may also affect function) may be addressed through a centralization procedure.
2) The forearm can theoretically be lengthened although I am not a strong believer in this operation (for patients with a diagnosis of RLD) as I believe forearm lengthening has limitations and the procedure may have numerous complications.  I do believe that centralization “lengthens” the forearm by placing the hand and wrist back on the end of the forearm making the forearm longer.
3) Providing a thumb is clearly the “home run” surgery for children with RLD as it markedly improves both function and appearance.
4) Limited finger motion is difficult to address in RLD and in other congenital conditions.

In the photos below, I believe the short forearm in the most notable difference.  The wrist has been centralized and is generally well aligned.  The index finger has been pollicized into the position of a thumb and generally looks good although with careful assessment, it is noticed.

RLD with a short forearm and a pollicized index finger as a thumb. 

Another view of patient with radial deficiency

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