Anatomical study of the masseteric and obturator nerves: Application to face transplant and reanimation procedures.

The masseteric nerve (MN) and the anterior branch of the obturator nerve (ON) that innervate the transferred gracilis muscle have proved highly efficient for reanimating paralyzed facial muscles when muscle transfer is required. Previous researchers have published the total axonal load for myelinated fibers in both nerves. However, the real motor axonal load has not been established.

Which is the function of a martin-gruber connection?

Clinical and diagnostic variations may occur due to the variable presence of a connection between the median and ulnar nerves in the forearm (Martin-Gruber anastomosis). This incidence has a wide range at 7%-40%. Most commonly, the connection between the nerves is considered to be composed of motor fibers; although, a sensory role has also been described.

Fascicular Topography of the Human Median Nerve for Neuroprosthetic Surgery.

One of the most sought-after applications of neuroengineering is the communication between the arm and an artificial prosthetic device for the replacement of an amputated hand or the treatment of peripheral nerve injuries. For that, an electrode is placed around or inside the median nerve to serve as interface for recording and stimulation of nerve signals coming from the fascicles that innervate the muscles responsible for hand movements. Due to the lack of a standard procedure, the electrode implantation by the surgeon is strongly based on intuition, which may result in poor performance of the neuroprosthesis because of the suboptimal location of the neural interface.

Are the interarytenoid muscles supplied by branches of both the recurrent and superior laryngeal nerves?

Objectives/hypothesis: It has been generally accepted that the branches of the internal branch of the superior laryngeal nerve to the interarytenoid muscle are exclusively sensory. However, some experimental studies have suggested that these branches may contain motor axons, and therefore that the interarytenoid muscle is supplied by both the superior and recurrent laryngeal nerves. The aim of this work was to determine whether motor axons to the interarytenoid muscles are present in both laryngeal nerves.

Somatotopic changes in the nucleus ambiguus after section and regeneration of the recurrent laryngeal nerve of the rat.

Changes in motoneurons innervating laryngeal muscles after section and regeneration of the recurrent laryngeal nerve (RLN) are far from being understood. Here, we report the somatotopic changes within the nucleus ambiguus (Amb) after the nerve injury and relates it to the resulting laryngeal fold impairment. The left RLN of each animal was transected and the stumps were glued together using surgical fibrin glue.

Reorganization of laryngeal motoneurons after crush injury in the recurrent laryngeal nerve of the rat.

Motoneurons innervating laryngeal muscles are located in the nucleus ambiguus (Amb), but there is no general agreement on the somatotopic representation and even less is known on how an injury in the recurrent laryngeal nerve (RLN) affects this pattern. This study analyzes the normal somatotopy of those motoneurons and describes its changes over time after a crush injury to the RLN. In the control group (control group 1, n = 9 rats), the posterior cricoarytenoid (PCA) and thyroarytenoid (TA) muscles were injected with cholera toxin-B.

Somatotopy of the neurons innervating the cricothyroid, posterior cricoarytenoid, and thyroarytenoid muscles of the rat's larynx.

Neurons innervating the intrinsic muscles of the larynx are located within the nucleus ambiguus but the precise distribution of the neurons for each muscle is still a matter for debate. The purpose of this study was to finely determine the position and the number of the neurons innervating the intrinsic laryngeal muscles cricothyroid, posterior cricoarytenoid, and thyroarytenoid in the rat. The study was carried out in a total of 28 Sprague Dawley rats.

Ulnar nerve innervation of the triceps muscle: real or apparent? An anatomic study.

Background: Since the 18th century, the existence of ulnar nerve innervation of the medial head of the triceps brachii muscle has been controversial. The evidence for or against such innervation has been based on macroscopic dissection, an unsuitable method for studying intraneural topography or intramuscular branching. The study of smaller specimens (embryos or fetuses) by means of serial histologic sections may resolve the controversy.

Morphogenesis of the human laryngeal ventricles.

Background: Two theories explain the origin of human laryngeal ventricles: (1) ventricles derive from the fifth pharyngeal pouches; (2) development independent from the pouches.

Methods: In all, there were 21 serially sectioned human embryos from stages 15 to 23, and 11 fetuses of 9 to 18 weeks. Computer-aided 3-dimentional reconstructions were made.

Recurrent laryngeal nerve landmarks revisited.

Background: The aim of this work was to evaluate, to prove their reliability, the different surgical landmarks previously proposed as a mean to locate the recurrent laryngeal nerve (RLN).

Methods: The necks of 143 (68 male and 76 female) human adult embalmed cadavers were examined. RLN origin and length and its relationship to different landmarks were recorded and results compared with those previously reported.

Functional role of human laryngeal nerve connections.

Objectives/hypothesis: Current knowledge of the functional role of human laryngeal nerves is based on traditional laryngeal neuroanatomic descriptions or contradictory electromyographic studies. The aim of this study was to clarify the functional role of neural connections between laryngeal nerves by correlating the different electromyographic patterns observed after laryngeal stimulation and the existence of different neural connections.

Study Design: Descriptive.

The central projections of the laryngeal nerves in the rat.

The larynx serves respiratory, protective, and phonatory functions. The motor and sensory innervation to the larynx controlling these functions is provided by the superior laryngeal nerve (SLN) and the recurrent laryngeal nerve (RLN). Classical studies state that the SLN innervates the cricothyroid muscle and provides sensory innervation to the supraglottic cavity, whereas the RLN supplies motor innervation to the remaining intrinsic laryngeal muscles and sensory innervation to the infraglottic cavity, but recent data suggest a more complex anatomical and functional organisation.

The clinical interest of the ary-thyro-cricoid fascicle.

The aim of this work was to study the prevalence and form of the ary-thyro-cricoid (ATC) muscular fascicle, a variable muscular slip connecting the oblique and/or transverse arytenoid muscles with the thyroarytenoid (TA) and/or lateral cricoarytenoid (LCA) muscles resembling a sphincter encircling the glottis. Thirty larynges obtained from necropsies of individuals with no known laryngeal pathology were dissected. The ATC fascicle was observed in 96.

Sigma receptor agonist 2-(4-morpholinethyl)1 phenylcyclohexanecarboxylate (Pre084) increases GDNF and BiP expression and promotes neuroprotection after root avulsion injury.

Spinal root avulsion leads to a progressive loss of axotomized motoneurons (MNs). Nowadays, there is no effective treatment to prolong MN survival that could permit recovery as a result of delayed surgical repair. Administration of Sigma-1 receptor (Sig-1R) ligands has been reported to promote beneficial effects after several types of neural injury.

Human laryngeal ganglia contain both sympathetic and parasympathetic cell types.

The presence of ganglia associated with the laryngeal nerves is well documented. In man, these ganglia have been less well studied than in other species and, in particular, the cell types within these ganglia are less well characterized. Using a panel of antibodies to a variety of markers found in the paraganglion cells of other species, we were able to show the existence of at least two populations of cells within human laryngeal paraganglia.

Topographical distribution of motor fascicles in the sciatic-tibial nerve of the rat.

Knowledge of the intraneural topography of peripheral nerves may help to improve nerve repair after injuries and the selectivity of neural interfaces. We studied the fascicular pattern of motor fibers of the rat sciatic-tibial nerve. We carried out an anatomical dissection of the muscular tributaries of the tibial nerve in the leg.

Anatomic study of human laryngeal ganglia: number and distribution.

We have studied 12 laryngeal nerves: six internal branches of the superior laryngeal nerve (ILN) and six recurrent laryngeal nerves (RLN) from three human adult larynges (two males and one female). After dissection of each individual laryngeal nerve using a surgical microscope, the nerves were preserved in 10% formalin, embedded in paraffin wax, serially sectioned transversely at a thickness of 10 microm and stained with hematoxylin and eosin. We found 2-4 ganglia associated with the ILN.

[On the number and morphometrical parameters of the nucleus ambiguous neurons after the injury and regeneration of the recurrent laryngeal nerve in the rat].

Introduction And Objectives: In laryngeal nerves injuries it is essential to know the morpho-functional reorganization of the neurons which supply the larynx in order to be successful with the clinical techniques of functional reinnervation and/or orthotopic transplant. Due to the lack of this type of studies in the literature, we investigated the organization of laryngeal motoneurons in the nucleus ambiguous (NA) after the axotomy and regeneration of the recurrent laryngeal nerve (RLN) in adult rats.

Material And Methods: We used biotinylated dextran amines (BDA, 3 kDa), this fact is an innovation in the field, because this is a novel methodological approach to this model.