Pronator quadratus muscle flap: a preliminary cadaveric study

There are very few studies regarding the neurovascular anatomy of pronator quadratus (PQ) or the technique of harvesting it as free functional muscle transfer. The aim of the study was to describe the neurovascular anatomy of PQ, to provide the harvesting technique and review the reported clinical applications. Dissections were performed on four fresh cadaver upper extremities. Measurements of PQ’s dimensions, its neurovascular pedicle length, diameter and branching pattern were taken, and photographs were taken. The relation of the neurovascular pedicle to important anatomic landmarks of the forearm was also documented. Identification and raising of the PQ was performed within 30 min on all cases. The neurovascular pedicle was lying over the flexor surface of the interosseous membrane and entered the PQ on its dorsal surface. In all cases, PQ was received its blood supply from the anterior interosseous artery (AIA) with an average length of 12 cm and average diameter of 2.25 mm and it was accompanied by two veins. There were interconnections between the AIA and the ulnar and radial arteries. PQ was innervated by the anterior interosseous nerve with an average length of 12.25 cm. PQ can be easily harvested either as a free or as a pedicled muscle. The learning curve is short. The accompanying vessels and nerve are of adequate length/diameter for microvascular anastomoses and/or neurorrhaphy, respectively. There is no donor site morbidity except the scar. Although there have been sporadic reports on PQ clinical applications, more studies are needed in order to identify the indications/applications in reconstructive surgery.