The authors report five cases of soft-tissue and metacarpal defects in the hand treated with a posterior interosseous pedicle flap and a vascularized segment of the ulna for bony reconstruction. The technique of flap harvest has been previously outlined. The authors describe additional details of the procedure when incorporating a segment of the ulna. Interestingly, this reconstruction was performed acutely in three of the cases, including gunshot and industrial injuries. The flap size ranged from 6x4 to 12x8 cm. The length of donated ulna ranged from 3-7 cm. The donor area was closed primarily in three cases and a skin graft was required in two. All flaps survived and union occurred without complication.
This paper describes the use of a posterior interosseous pedicle flap with vascularized bone from the ulna to provide coverage and treat bone loss in the hand. The technique is technically demanding and the vessels for this flap very small. We have found it to be a somewhat tenuous flap and anecdotally, adding a vein for additional venous drainage may be helpful to improve flap survival. Once mastered, it can be raised quite rapidly and is useful to cover small areas about the hand, especially the first web space. The donor site is more cosmetic than the radial forearm flap. It is unclear if the addition of vascularized bone is required for osteosynthesis in the hand. One would not want to compromise bone reconstruction due to the limitations of the transposed segment of ulna. This would also seem to add potential morbidity to the forearm. Fracture after osteocutaneous radial forearm flaps have been reported, although the ulna may see less torsional and bending stresses than the radius. For the ulna to be vascular, it must be harvested from the proximal two-thirds of the bone with a portion of the extensor pollicus longus muscle. The advantages of the flap are that it burns no bridges and does not lead to sacrifice of one of the major blood vessels to the hand. It would seem to be a useful alternative in this particular injury pattern, with full thickness dorsal hand loss and an isolated metacarpal defect.
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Plastic and Reconstructive Surgery