Treatment of RADIAL APLASIA

Radial Aplasia – especially with thumbs present – is a rare medical condition. Deciding how to treat the resulting radial deviation of the hand – or, in some instances, whether to intervene at all – is challenging because the available options are far from ordinary, (almost) always successful procedures.

The most pressing issue for us was recurrence – not only having to deal with radial deviation again but with the additional risk of ending up with an ulnocarpal fusion and/or growth arrest, presumably a worse outcome than not treating the radial deviation at all.

There is no lack of studies finding high recurrence rates in Centralizations. While Radializations have been a significant improvement, a risk of recurrence seems to persist  – see, for example, here, here, and here. The surgeons we were recommended to treat our daughter in Germany via Radialization explicitly warned us that recurrence was likely, at least to a certain degree, and almost guaranteed if we did not ensure our daughter would wear splints at night until she was fully grown, around 16 years old. To our knowledge, except for Ulnarization, there are no other promising procedures.

After unsatisfactory results over many years, some institutions have abandoned offering Centralizations and Radializations altogether and settled on less intrusive interventions where the recurrence of radial deviation is fully expected (source). Note that this paper from 2020 includes many citations but does not mention Dr. Paley’s or Dr. Standard’s work.

Radialization, a substantial improvement over Centralization, was proposed by Dieter Buck-Gramko in 1985 – almost 40 years ago, and to this day, is the standard procedure in Europe. Ulnarization, while a younger technique, is not a novelty – it dates back to 1999 (Generation 1, which included external fixation). Working on issues that occurred in some patients (like a bump related to the ulnar head becoming prominent on the radial side and gravity-related dynamic ulnar deviation), Dr. Paley started to shorten the ulna during the procedure and switched from external to internal fixation (Generation 2).

Since the shortening did not resolve the «ulna bump» issue, Dr. Paley modified the procedure again in 2019 (releasing a ligament between two carpal bones – scaphoid and lunate – to make room for the ulnar head). This is the now-current Generation 3 (as of December 2023).

Note that none of the three generations of Ulnarization showed recurring deformities or growth arrests. There are many other advantages of Ulnarization over Centralization and Radialization, for instance, requiring fewer surgeries and no external fixation. More details on Ulnarization and images can be found here and here.

We also know about parents who decide not to intervene at all, and there are plenty of instances of children, and then adults, who cope very well with this condition. Since this was never an option for us, we cannot say more about it.