gms | German Medical Science

Objectives/Interrogation: Through an anatomical review, the primary aim of this study was to delineate the dorsal thumb metacarpal (TM) periosteal branches of the radial artery (RA). In addition, we report here the clinical and radiological outcomes of a vascularized TM periosteal pedicled flap (VTMPF), supplied by the first dorsal metacarpal artery (FDMA), in a cohort of scaphoid nonunion in an adolescent.

Methods: Ten latex-colored upper limbs from fresh human cadavers were used. Branches of the RA were dissected, noting the periosteal, muscular, and cutaneous branches arising from the FDMA and the radial branch (RB) of the first dorsal intermetacarpal artery (FDIA).

Sixteen patients under age 18 years with scaphoid nonunion, who underwent a VTMPF procedure without bone grafting, were included for this prospective cohort study at a mean follow-up of 10.9 months. Patients were operated on by three different hand surgeons at three hand surgery institutions. All patients received a VTMVF, but with different scaphoid internal fixation modalities, in 14 cases using one or two retrograde 2mm headless compression screws and in 2 cases were not required stabilization.

Results: The FDMA provided a mean 12 periosteal branches (range 9 to 15), and the RB of the FDIA provided a mean five periosteal branches to the dorsal aspect of the TM (range 4-7).

In 13 boys and 3 girls, the mean age was 16.2 years. There were two type D1 nonunions (Herbert classification), six type D2, five type D3, and three type D4. Seven patients previously had undergone an unsuccessful surgical attempt to treat their nonunion. The mean anterior bone defect was 3 mm in length. The patients experienced no postoperative complications. Successful consolidation was achieved in all cases, with 82% cross sectional trabecular bridging at 12 weeks. Pain subsided after surgery and patients experienced improvements in both their QuickDASH and MMWS scores. Overall 34% and 40% gains in strength and wrist motion, relative to the contralateral normal side, were observed. At final follow-up, there were differences between the preoperative versus postoperative hand in wrist range of motion, or either grip or pinch strength.

Conclusions: In this study, the use of VTMPF for scaphoid nonunion in children and adolescents is associated with general good outcomes.