Diagnostic Usefulness of Neuromuscular Ultrasound in Anatomical Localization of Peripheral Nerve Injury: Detailed Lesion Localization Using Neuromuscular Ultrasound in a Patient with Traumatic Ulnar Nerve Injury at the Hand

Complications of peripheral nerve injury arising from the surgical treatment of carpal tunnel syndrome are not uncommon. No documented report of the association of ulnar nerve injury with carpal tunnel decompression has been found. This case-study describes partial laceration of the ulnar nerve as a complication of carpal tunnel surgery and reviews the literature on this subject.

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Acellular Nerve Allografts in Major Peripheral Nerve Repairs: An Analysis of Cases Presenting With Limited Recovery

Hand ◽

10.1177/15589447211003175 ◽

2021 ◽

pp. 155894472110031

Author(s):

Blair R. Peters ◽

Matthew D. Wood ◽

Daniel A. Hunter ◽

Susan E. Mackinnon

Keyword(s):

Peripheral Nerve ◽

Nerve Injury ◽

Ulnar Nerve ◽

Current Literature ◽

Axonal Regeneration ◽

Large Diameter ◽

Nerve Injuries ◽

Myelinated Axons ◽

Acellular Nerve Allograft ◽

Ulnar Nerve Injury

Background: Acellular nerve allografts have been used successfully and with increasing frequency to reconstruct nerve injuries. As their use has been expanded to treat longer gap, larger diameter nerve injuries, some failed cases have been reported. We present the histomorphometry of 5 such cases illustrating these limitations and review the current literature of acellular nerve allografts. Methods: Between 2014 and 2019, 5 patients with iatrogenic nerve injuries to the median or ulnar nerve reconstructed with an AxoGen AVANCE nerve allograft at an outside hospital were treated in our center with allograft excision and alternative reconstruction. These patients had no clinical or electrophysiological evidence of recovery, and allograft specimens at the time of surgery were sent for histomorphological examination. Results: Three patients with a median and 2 with ulnar nerve injury were included. Histology demonstrated myelinated axons present in all proximal native nerve specimens. In 2 cases, axons failed to regenerate into the allograft and in 3 cases, axonal regeneration diminished or terminated within the allograft. Conclusions: The reported cases demonstrate the importance of evaluating the length and the function of nerves undergoing acellular nerve allograft repair. In long length, large-diameter nerves, the use of acellular nerve allografts should be carefully considered.

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Anesthetic Block of Pain-related Cortical Activity in Patients with Peripheral Nerve Injury Measured by Magnetoencephalography

Anesthesiology ◽

10.1097/aln.0b013e31821f6562 ◽

2011 ◽

Vol 115 (2) ◽

pp. 375-386 ◽

Cited By ~ 2

Author(s):

Peter J. Theuvenet ◽

Jan C. de Munck ◽

Maria J. Peters ◽

Jan M. van Ree ◽

Fernando L. Lopes da Silva ◽

...

Keyword(s):

Neuropathic Pain ◽

Peripheral Nerve ◽

Nerve Injury ◽

Ulnar Nerve ◽

Peripheral Nerve Injury ◽

Cortical Activation ◽

Control Group ◽

Global Field Power ◽

Before And After ◽

Local Block

Background This study examined whether chronic neuropathic pain, modulated by a local anesthetic block, is associated with cortical magnetic field changes. Methods In a group of 20 patients with pain caused by unilateral traumatic peripheral nerve injury, a local block with lidocaine 1% was administered and the cortical effects were measured and compared with a control group. The global field power (GFP), describing distribution of cortical activation after median and ulnar nerve stimulation, was plotted and calculated. The effects on the affected hemisphere and the unaffected hemisphere (UH) before and after a block of the injured nerve were statistically evaluated. Results Major differences based on the GFP curves, at a component between 50 ms - 90 ms (M70), were found in patients: in the affected hemisphere the M70 GFP peak values were statistically significantly larger in comparison with the UH, and the GFP curves differed morphologically. Interestingly, the mean UH responses were reduced in comparison with the control group, a finding suggesting that the UH is also part of the cortical changes. At M70, the GFP curves and values in the affected hemisphere were modulated by a local block of the median or the ulnar nerve. The most likely location of cortical adaptation is in the primary somatosensory cortex. Conclusions Cortical activation is enhanced in the affected hemisphere compared with the UH and is modulated by a local block. The UH in neuropathic pain changes as well. Evoked fields may offer an opportunity to monitor the effectiveness of treatments of neuropathic pain in humans.

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The Efficacy of a Scaffold-free Bio 3D Conduit Developed from Autologous Dermal Fibroblasts on Peripheral Nerve Regeneration in a Canine Ulnar Nerve Injury Model: A Preclinical Proof-of-Concept Study

Cell Transplantation ◽

10.1177/0963689719855346 ◽

2019 ◽

Vol 28 (9-10) ◽

pp. 1231-1241 ◽

Cited By ~ 2

Author(s):

Sadaki Mitsuzawa ◽

Ryosuke Ikeguchi ◽

Tomoki Aoyama ◽

Hisataka Takeuchi ◽

Hirofumi Yurie ◽

...

Keyword(s):

Peripheral Nerve ◽

Nerve Regeneration ◽

Nerve Injury ◽

Ulnar Nerve ◽

Nerve Fibers ◽

Dermal Fibroblasts ◽

Alternative Methods ◽

Segmental Nerve ◽

Injury Model ◽

Ulnar Nerve Injury

Autologous nerve grafting is widely accepted as the gold standard treatment for segmental nerve defects. To overcome the inevitable disadvantages of the original method, alternative methods such as the tubulization technique have been developed. Several studies have investigated the characteristics of an ideal nerve conduit in terms of supportive cells, scaffolds, growth factors, and vascularity. Previously, we confirmed that biological scaffold-free conduits fabricated from human dermal fibroblasts promote nerve regeneration in a rat sciatic nerve injury model. The purpose of this study is to evaluate the feasibility of biological scaffold-free conduits composed of autologous dermal fibroblasts using a large-animal model. Six male beagle dogs were used in this study. Eight weeks before surgery, dermal fibroblasts were harvested from their groin skin and grown in culture. Bio 3D conduits were assembled from proliferating dermal fibroblasts using a Bio 3D printer. The ulnar nerve in each dog’s forelimb was exposed under general anesthesia and sharply cut to create a 5 mm interstump gap, which was bridged by the prepared 8 mm Bio 3D conduit. Ten weeks after surgery, nerve regeneration was investigated. Electrophysiological studies detected compound muscle action potentials (CMAPs) of the hypothenar muscles and motor nerve conduction velocity (MNCV) in all animals. Macroscopic observation showed regenerated ulnar nerves. Low-level hypothenar muscle atrophy was confirmed. Immunohistochemical, histological, and morphometric studies confirmed the existence of many myelinated axons through the Bio 3D conduit. No severe adverse event was reported. Hypothenar muscles were re-innervated by regenerated nerve fibers through the Bio 3D conduit. The scaffold-free Bio 3D conduit fabricated from autologous dermal fibroblasts is effective for nerve regeneration in a canine ulnar nerve injury model. This technology was feasible as a treatment for peripheral nerve injury and segmental nerve defects in a preclinical setting.

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