No abstract

Neurotechnology attempts to develop supernumerary limbs, but can the human brain deal with the complexity to control an extra limb and yield advantages from it? Here, we analyzed the neuromechanics and manipulation abilities of two polydactyly subjects who each possess six fingers on their hands. Anatomical MRI of the supernumerary finger (SF) revealed that it is actuated by extra muscles and nerves, and fMRI identified a distinct cortical representation of the SF. In both subjects, the SF was able to move independently from the other fingers. Polydactyly subjects were able to coordinate the SF with their other fingers for more complex movements than five fingered subjects, and so carry out with only one hand tasks normally requiring two hands. These results demonstrate that a body with significantly more degrees-of-freedom can be controlled by the human nervous system without causing motor deficits or impairments and can instead provide superior manipulation abilities.

No abstract

No abstract

HNA AAAs can be successfully treated with EVAR. However, surveillance is necessary to detect and treat late type I endoleaks in HNA patients.

Lower extremity soft tissue defects frequently result from high-energy trauma or oncological resection. The lack of suitable muscle flap options for the distal leg and foot makes defects in these locations especially challenging to reconstruct and free tissue transfer is commonly used. Another option that has become more popular in the past two decades are pedicled perforator flaps. Based on a thorough literature review and the authors’ experience on leg perforator flaps for over a decade, this article presents a historical review, the anatomical basis of common perforator flaps of the leg and foot, patient selection, wound selection, perforator selection, flap design, surgical techniques, refinements, and postoperative care. A review of the clinical outcomes and complications of these flaps was also performed and was noted to be comparable to the outcomes of free tissue transfer with significantly lower total flap failure rate. It is hoped that this review will assist surgeons in the formulation of a comprehensive step-by-step guide in performing pedicled perforator flap reconstruction of the lower extremity.

No abstract

Background: Nerve transfers are planned based on the following parameters: location, number of branches, and axon count matching of the donor and recipient nerves. The authors have previously defined the former two in upper limb muscles. In the literature, axon counts are obtained from various sources, using different methods of histomorphometry. This study describes the axon counts of the same primary motor nerve branches from the authors’ previous study using a uniform method of manual histomorphometry and completes the authors’ blueprint of upper limb neuromuscular anatomy for reconstructive surgery. Methods: The distal ends of the primary nerve branches of 23 upper limb muscles were harvested from 10 fresh frozen cadaveric upper limbs. Manual quantitative histomorphometry was performed by two independent investigators, and the average was reported. Results: The primary nerve branches of the arm muscles had higher average axon counts (range, 882 to 1835) compared with those of the forearm muscles (range, 267 to 883). In the forearm, wrist flexor (range, 659 to 746) and extensor (range, 543 to 745) nerve branches had axons counts that were similar to those of potential donors (e.g., supinator, n = 602; pronator teres, n = 625; flexor digitorum superficialis, n = 883; and flexor digitorum profundus, n = 832). Conclusions: Apart from describing the axon counts of the upper limb, the authors have found that the forearm axon counts are very comparable. This insight, when combined with information on the location and number of primary nerve branches, will empower surgeons to tailor bespoke nerve transfers for every clinical situation.