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.

Cadaveric Nerve Allograft: Single Center's Experience in a Variety of Peripheral Nerve Injuries.

The purpose of this study is to report a single center's experience with cadaveric nerve allograft (CNA) for functional restoration after traumatic nerve injuries including the head and neck region. Sixteen patients were included in the current study. Ages ranged from 5 to 62 years, with a mean age of 35 years. The main indication for the use of CNA was nerve gaps of at least 10 mm in which both the proximal and distal stumps of the injured nerves were available. Only allografts from cadavers were used, and none of the patients underwent immunosuppressive treatment. Denervation time average was 12 weeks, with an average gap length of 65 mm. Most cases were located in the upper extremity (73%) and 80% were secondary to trauma. Most nerves involved were sensory, followed by mixed nerves and 2 patients with facial paralysis. Sensory recovery was graded as good and excellent in 91.7%. Motor recovery was graded as good in 33%. The results of the current study suggest that peripheral nerve injuries can successfully be treated by the use of CNA and may be used in larger nerve gaps and for unconventional uses, although caution should be used specifically in mixed or motor nerves and high level of injury. Avoiding donor site morbidity, minimizing operative time, and availability are the most important advantages of using CNA over autologous nerve grafts.

Successful Separation of Conjoined Twins: The Contemporary Experience and Historic Review in Memphis.

Conjoined twins are a rare phenomenon with historically poor outcomes after separation. We present a review of 8 sets of conjoined twins operated on in Memphis, Tenn, from 1953-2016. Except for 1 set of twins, before 2010, all experienced at least 1 fatality either before, during, or as a result of separation. Since 2010, we have separated an additional 2 sets of conjoined twins with no mortality related to the separation, although 1 of the first twins had significant cardiac and respiratory abnormalities and died several years after the separation. Each set of twins presented many challenges in reconstruction; however, the use of tissue expansions in the 2 most recent sets of twins proved to be beneficial. Although improvements in imaging, surgical technology, and postoperative monitoring likely have contributed to the increased survival, previous experience and meticulous planning with a multidisciplinary approach may have been the most influential.