The keystone flap can be applied to large defects of the trunk and extremities, obviating the need for either microsurgical techniques or extensive operative time while achieving primary wound healing. Despite minor complications, the 97 percent reconstructive success rate compares well to published rates of microsurgical tissue transfers but has several advantages: short operative times, high reproducibility, ease of use, and favorable aesthetic outcome. The authors conclude that the keystone flap is a reliable and effective reconstructive surgical technique for reconstruction of soft-tissue defects.

Successfully and efficiently bridging peripheral nerve gaps without the use of autografts is a substantial clinical advance for peripheral nerve reconstructions. Novel templating methods for the fabrication of conductive hydrogel guidance channels for axonal regeneration are designed and developed. PEDOT is electrodeposited inside the lumen to create fully coated-PEDOT agarose conduits and partially coated-PEDOT agarose conduits.

Summary: Painful neuromas result from traumatic injuries of the hand and digits and cause substantial physical disability, psychological distress, and decreased quality of life among affected patients. The regenerative peripheral nerve interface (RPNI) is a novel surgical technique that involves implanting the divided end of a peripheral nerve into a free muscle graft for the purposes of mitigating neuroma formation and facilitating prosthetic limb control. The RPNI is effective in treating and preventing neuroma pain in major extremity amputations. The purpose of this study was to determine if RPNIs can be used to effectively treat neuroma pain following partial hand and digital amputations. We retrospectively reviewed the use of RPNI to treat symptomatic hand and digital neuromas at our institutions. Between November 2014 and July 2019, we performed 30 therapeutic RPNIs on 14 symptomatic neuroma patients. The average patient follow-up was 37 weeks (6–128 weeks); 85% of patients were pain-free or considerably improved at the last office visit. The RPNI can serve as a safe and effective surgical solution to treat symptomatic neuromas after hand trauma.

Nonmetallic, biosynthetic acellular muscle-poly(3,4-ethylenedioxythiophene) peripheral nervous system interfaces both sense and stimulate physiologically relevant efferent and afferent action potentials in vivo. This demonstrates their relevance not only as a nerve-electronic coupling device capable of reaching the long-sought goal of closed-loop neural control of a prosthetic limb, but also in a multitude of other bioelectrical applications.

Despite significant burn treatment advances, modern multidisciplinary care, and improved survival after burns, facial burn scars remain clinically challenging. Achieving a successful reconstruction requires a comprehensive approach, entailing many advanced techniques with an emphasis on preserving function and balancing intricate aesthetic requirements. Pediatric facial burns present the same reconstructive challenges seen in adults, with additional developmental and psychologic concerns. In this paper, we describe the basic principals of facial burn care in the pediatric burn population, with a specific focus on lower-eyelid burn ectropion and oral commissure burn scar contracture leading to microstomia. Several cases are demonstrated.

The purpose of this study is to optimize poly(3,4,-ethylenedioxythiophene) (PEDOT) polymerization into decellular nerve scaffolding for interfacing to peripheral nerves. Our ultimate aim is to permanently implant highly conductive peripheral nerve interfaces between amputee, stump, nerve fascicles and prosthetic electronics. Decellular nerve (DN) scaffolds are an FDA approved biomaterial (Axogen ) with the flexible tensile properties needed for successful permanent coaptation to peripheral nerves. Biocompatible, electroconductive, PEDOT facilitates electrical conduction through PEDOT coated acellular muscle. New electrochemical methods were used to polymerize various PEDOT concentrations into DN scaffolds without the need for a final dehydration step. DN scaffolds were then tested for electrical impedance and charge density. PEDOT coated DN scaffold materials were also implanted as 15–20mm peripheral nerve grafts. Measurement of in-situ nerve conduction immediately followed grafting. DN showed significant improvements in impedance for dehydrated and hydrated, DN, polymerized with moderate and low PEDOT concentrations when they were compared with DN alone (a ≤ 0.05). These measurements were equivalent to those for DN with maximal PEDOT concentrations. In-situ, nerve conduction measurements demonstrated that DN alone is a poor electro-conductor while the addition of PEDOT allows DN scaffold grafts to compare favorably with the “gold standard”, autograft (Table 1). Surgical handling characteristics for conductive hydrated PEDOT DN scaffolds were rated 3 (pliable) while the dehydrated models were rated 1 (very stiff) when compared with autograft ratings of 4 (normal). Low concentrations of PEDOT on DN scaffolds provided significant increases in electro active properties which were comparable to the densest PEDOT coatings. DN pliability was closely maintained by continued hydration during PEDOT electrochemical polymerization without compromising electroconductivity.

Plastic surgeons are frequently faced with difficult and challenging soft tissue defects in all areas of the body. To reconstruct these defects, there are many operative approaches available to the reconstructive surgeon including skin grafts, local flaps, regional flaps, and free-tissue transfer. Despite these many options, occasionally the best alternative for reconstruction of a wound is tissue expansion, where skin of similar quality, texture, and color can be used to close a soft tissue defect. Unfortunately, there are significant problems related to tissue expander reconstruction including a complication rate as high as 50%. As a result, tissue expander reconstruction has not achieved the widespread popularity commensurate with its potential clinical utility. To reduce the complication rate related to open tissue expander placement, and consequently to improve its clinical utility, we have employed endoscopic techniques for the placement of tissue expanders. Endoscopic approaches are currently being used in many areas of surgery and have resulted in substantial benefits. Endoscopic placement of tissue expanders has the benefit of reducing operative time, major complication rate, time to full expansion, and length of hospital stay. The purpose of this article is to critically examine the current open technique for tissue expander placement and to compare this technique with minimally invasive endoscopic tissue expander placement. We will discuss in detail the current problems associated with open tissue expander placement, the benefits of endoscopic tissue expansion, the technique of endoscopic tissue expander placement, and the outcomes for these techniques.

Background Our goal is to develop a peripheral nerve electrode with long-term stability and fidelity for use in nerve-machine interfaces. Microelectromechanical systems (MEMS) use silicon probes that contain multi-channel actuators, sensors, and electronics. We tested the null hypothesis that implantation of MEMS probes do not have a detrimental effect on peripheral nerve function or regeneration. Methods A rat hindlimb, peroneal nerve model was utilized in all experimental groups: a) intact nerve (Control, n= 10); b) nerve division and repair (Repair, n= 9); and c) Nerve division, insertion of MEMS probe, and repair (Repair + Probe, n=9). Nerve morphology, nerve to muscle compound action potential (CMAP) studies, walking tracks, and extensor digitorum longus (EDL) muscle function tests were evaluated following an 80 day recovery. Results Repair and Repair + Probe showed no differences in axon count, axon size, percent non-neural area, CMAP amplitude, latency, muscle mass, muscle force, or walking track scores. Though there was some local fibrosis around each MEMS probe, this did not lead to measurable detrimental effects in any anatomic or functional outcome measurements. Conclusions The lack of a significant difference between Repair and Repair + Probe groups in histology, CMAP, walking tracks, and muscle force suggests that MEMS electrodes are compatible with regenerating axons and show promise for establishing chemical and electrical interfaces with peripheral nerves.