Nonvascularized Iliac Crest Bone Graft for Reconstruction of the First Metacarpal in Type IIIB Thumb Hypoplasia: A Radiographic Follow-Up Study.

PURPOSE: To present a radiographic follow-up study of the use of a nonvascularized iliac crest bone graft as a treatment for modified Blauth type IIIB thumb hypoplasia.

METHODS

From January 2015 to December 2019, nonvascularized iliac crest bone grafts were used to reconstruct the first metacarpal in 23 cases with type IIIB thumbs. The average follow-up duration was 1.9 years (range 1.0-3.9 years). We evaluated the patients' serial x-rays and measured the width and length changes of the reconstructed first metacarpals.

RESULTS

Survival of the graft, judged radiographically, was achieved in 20 cases (20/23, 87%), with an average reduction of 33% in the width of the graft. Shortening of the graft (average 2.3 mm, range 0.1-5.6 mm) was noted in 11 of the 20 cases, and an increase in the length of the graft (average 4.2 mm, range 0.7-8.6 mm) was observed in the other 9. Bone graft failure (3/23, 13%) occurred in 3 cases because of significant bone resorption.

CONCLUSIONS

For type IIIB thumb hypoplasia, a nonvascularized iliac crest bone graft was a feasible method to reconstruct the first metacarpal, with a 13% risk of graft failure, 33% average reduction in graft width, and 55% reduction in graft length. However, in cultures that value the preservation of a 5-digit hand, this technique may provide an alternative to excision with index pollicization.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.