A Modified Bilhaut–Cloquet Procedure for Zigzag Thumb Polydactyly Types III and IV

Background: A review of the English literature over the least 43 years revealed only a total of 53 cases of Wassel types III, IV, and VII treated by the Bilhaut–Cloquet (B–C) procedure. Furthermore, the detailed results and range of motion were only given in 2 series (a total of 9 cases). Methods: Four cases of Wassel types III and IV thumb duplications with zigzag deformity were treated with a modified B–C procedure. The main modification was minimal central resections at the joints aiming for joint preservation to improve the postoperative range of motion of the new thumb. Results: The results showed an excellent overall functional score (Tada score of 5 of 5 in all cases). The mean range of motion at the metacarpophalangeal joint was excellent (60°), but the mean at the interphalangeal joint was only 20°. Cosmetically, all thumbs were "too wide" and a panel of 3 hand surgeons scored the cosmetic result (0–10 scoring system) between 5.7 and 6.7. No secondary procedures were done, and all parents were "very satisfied" despite the wide thumbs and split nails. This was attributed to the presence of an ugly preoperative zigzag appearance, and hence the comparative postoperative appearance was satisfactory. Conclusion: The modified B–C procedure gives a satisfactory function, but the cosmetic outcome is suboptimal.