Evaluation of versatility and outcomes of the first dorsal metacarpal artery flap in thumb defects

Abstract

Background: It is clinically vital to determine the best technique to reconstruct thumb defects with satisfactory esthetic and functional outcomes. We aimed to quantitatively present the safety, versatility, limitations, advantages, and functional results of the first dorsal metacarpal artery flap (FDMAF) and evaluate its outcomes in thumb defect reconstruction by comparing it with the other current surgical options.

Methods: A total of 21 patients underwent thumb defect reconstruction. They were evaluated with the following parameters: Etiology, age, timing of reconstruction, flap vitality, Semmes-Weinstein monofilament (SWM) test, static two-point discrimination (2PD) test, pain, cortical reorientation, cold intolerance questionnaire, and Michigan hand outcomes questionnaire. Their functional outcomes were evaluated by comparing their scores with the other current surgical options published in the literature.

Results: The mean follow-up period was 22.3 months. The mean pain score of the flap was 0.4±0.6 and no patient had pain in the donor area (range, 0-10). The sensory outcome was 'good' (8.6 mm) based on the static 2PD test. The mean SWM test score was 4.02 g. Patient satisfaction was 4.6 according to the Michigan hand outcomes questionnaire (range, 0-5). The cold intolerance questionnaire scores showed that the patients had mild cold intolerance (mean, 10.5; range 0-100). Complete cortical reorientation was seen in 81% of the patients.

Conclusion: Restoration of the innervation of thumb defects is possible with the FDMAF with high satisfaction rates based on our results. The absence of the microsurgical vessel or nerve repair facilitates the surgery, shortens its duration, and reduces morbidity, reserving the microsurgical options for more complicated cases. Therefore, it can be concluded that the FDMAF is an effective flap with great modifications for complicated thumb defects but surgeons should consider their clinical outcomes and prolonged surgery when choosing which technique to be used.

Figure 1

Reconstruction of a thumb pulp defect with the first dorsal metacarpal artery flap (FDMAF). (a) Intraoperative view of the defect after debridement. (b) Elevation of the FDMAF. (c) Appearance of the skin graft at the donor site after 5 days. (d) Post-operative 2 years. Note good contour of the pulp and fullness of the flap with favorable esthetic appearance. (e) The donor site after 2 years with good esthetic appearance.

Figure 2

(a) Pre-operative view. (b) Reconstruction of the thumb defect after an oncologic resection. Note the skin left above the pedicle.

Figure 3

(a) Pre-operative view. (b and c) Post-operative views 2 years after reconstruction with the FDMAF. Note good contour and fullness of the pulp, and minimal scar at the donor site.