Coincidence between the distribution of myofascial trigger points and the presence of blood vessels in the gastrocnemius muscle: Implications for invasive procedures.

PURPOSE: The gastrocnemius venous system presents different anatomical variants. There have been described four locations of myofascial trigger points (MTrPs) in this muscle. However, no studies have analyzed the coincidence between vessels and MTrPs present in the gastrocnemius. Therefore, the main objective was to study the anatomical variability of the venous system by ultrasound and its coincidence with the location of the MTrPs. METHODS: A total of 100 lower limbs were studied. The gastrocnemius vessels were analyzed one by one by sector (medial, central, and lateral), quantifying the number of vessels, their distribution, and the coincidence with MTrPs. RESULTS: All muscle heads showed at least one vessel per section. A large variability was observed, from one to eight vessels per muscle head, with the most frequent number being three in the gastrocnemius medialis and two in the gastrocnemius lateralis. In all cases, the location of the vessels coincided with the MTrPs. CONCLUSIONS: The proximal gastrocnemius venous pattern is very variable between subjects in number of vessels and distribution, which has made it impossible to define a "safe" approach window for invasive procedures without ultrasound guidance. The coincidence between the clinical location of MTrPs of the gastrocnemius and the presence of vessels is total.

Shock waves as treatment of mouse myofascial trigger points.

INTRODUCTION: An abnormal increase in spontaneous neurotransmission can induce subsynaptic knots in the myocyte called myofascial trigger points. The treatment of choice is to destroy these trigger points by inserting needles. However, 10% of the population has a phobia of needles, blood, or injuries. Therefore, the objective of this study is to verify the usefulness of shock waves in the treatment of myofascial trigger points. METHODS: Two groups of mice have been developed for this: healthy muscles treated with shock waves; trigger points affected muscles artificially generated with neostigmine and subsequently treated with shock waves. Muscles were stained with methylene blue, PAS-Alcian Blue, and labeling the axons with fluorescein and the acetylcholine receptors with rhodamine. Using intracellular recording the frequency of miniature endplate potentials (mEPPs) was recorded and endplate noise was recorded with electromyography. RESULTS: No healthy muscles treated with shock waves showed injury. Twitch knots in mice previously treated with neostigmine disappeared after shock wave treatment. Several motor axonal branches were retracted. On the other hand, shock wave treatment reduces the frequency of mEPPs and the number of areas with endplate noise. DISCUSSION: Shock waves seem to be a suitable treatment for myofascial trigger points. In the present study, with a single session of shock waves, very relevant results have been obtained, both functional (normalization of spontaneous neurotransmission) and morphological (disappearance of myofascial trigger points). Patients with a phobia of needles, blood, or injuries who cannot benefit from dry needling may turn to noninvasive radial shock wave treatment.

Cadaveric and radiologic study of the anatomical variations of the prostatic arteries: A review of the literature and a new classification proposal with application to prostatectomy.

Development of prostatic arterial embolization (PAE) to treat benign prostatic hyperplasia (BPH) has raised interest in the variations of the prostatic arteries (PA). The aim of this study is to identify these vascular variations, to compare them with previous data, and to propose a simple classification. Ten adult male pelvis sides from embalmed cadavers were dissected, ages 69 to 92 years, and 10 PA were examined. In a retrospective analysis of 34 DSA pelvic angiographies on 28 patients aged 50 to 90 years, 48 PA were identified. A total of 58 PA were therefore analyzed. Six types are defined. Type I: PA originates from the anterior division (AD) of the internal iliac artery (IIA), 20.7%; Type II: PA emerges from the obturator artery (OA), 5.2%; type III: PA arises from the gluteal-pudendal trunk (GPT), 27.5%; Type IV: PA originates from the internal pudendal artery (IPA), 29.3%; Type V: PA comes from the middle rectal artery (MRA), 15.5%. Other origins, not observed in our sample but described in the literature, were amalgamated under Type VI. The AD/GPT/IPA stem is the main source of the PA. Analysis of the definitions of IIA branches and the associated terminology is necessary for interpreting the results reported by several authors on different samples, but in general the results fit the meta-analysis well. A new, simple, and complete classification for vascular variations of the PA is proposed. Clin. Anat. 30:71-80, 2017. © 2016 Wiley Periodicals, Inc.

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. In the experimental groups the left RLN of each animal was crushed with a fine tip forceps and, after several survival periods (1, 2, 4, 8, 12 weeks; minimum six rats per time), the PCA and TA muscles were injected as described above. After each surgery, the motility of the vocal folds was evaluated. Additional control experiments were performed; the second control experiment (control group 2, n = 6 rats) was performed labeling the TA and PCA immediately prior to the section of the superior laryngeal nerve (SLN), in order to eliminate the possibility of accidental labeling of the cricothyroid (CT) muscle by spread from the injection site. The third control group (control group 3, n = 5 rats) was included to determine if there is some sprouting from the SLN into the territories of the RLN after a crush of this last nerve. One week after the crush injury of the RLN, the PCA and TA muscles were injected immediately before the section of the SLN. The results show that a single population of neurons represents each muscle with the PCA in the most rostral position followed caudalwards by the TA. One week post-RLN injury, both the somatotopy and the number of labeled motoneurons changed, where the labeled neurons were distributed randomly; in addition, an area of topographical overlap of the two populations was observed and vocal fold mobility was lost. In the rest of the survival periods, the overlapping area is larger, but the movement of the vocal folds tends to recover. After 12 weeks of survival, the disorganization within the Amb is the largest, but the number of motoneurons is similar to control, and all animals recovered the movement of the left vocal fold. Our additional controls indicate that no tracer spread to the CT muscle occurred, and that many of the labeled motoneurons from the PCA after 1 week post-RLN injury correspond to motoneurons whose axons travel in the SLN. Therefore, it seems that after RLN injury there is a collateral sprouting and collateral innervation. Although the somatotopic organization of the Amb is lost after a crush injury of the RLN and does not recover in the times studied here, the movement of the vocal folds as well as the number of neurons that supply the TA and the PCA muscles recovered within 8 weeks, indicating that the central nervous system of the rat has a great capacity of plasticity.

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 current neuroanatomical tracing study was undertaken to provide a comprehensive description of the central brainstem connections of the axons within the SLN and the RLN, including those neurons that innervate the larynx. The study has been carried out in 41 adult male Sprague-Dawley rats. The central projections of the laryngeal nerves were labelled following application of biotinylated dextran amines onto the SLN, the RLN or both. The most remarkable result of the study is that in the rat the RLN does not contain any afferent axons from the larynx, in contrast to the pattern observed in many other species including man. The RLN supplied only special visceromotor innervation to the intrinsic muscles of the larynx from motoneurons in the nucleus ambiguus (Amb). All the afferent axons innervating the larynx are contained within the SLN, and reach the nucleus of the solitary tract. The SLN also contained secretomotor efferents originating from motoneurons in the dorsal motor nucleus of the vagus, and special visceral efferent fibres from the Amb. In conclusion, the present study shows that in the rat the innervation of the larynx differs in significant ways from that described in other species.

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. One population contained chromogranin and tyrosine hydroxylase representing a neurosecretory population possibly secreting dopamine. A second population of choline acetyltransferase positive cells would appear to have a putative parasympathetic function. Further work is needed to characterize these cell populations more fully before it will be possible to assign functions to these cell types but our results are consistent with the postulated functions of these ganglia as chemoreceptors, neurosecretory cells, and regulators of laryngeal mucus secretion.

[On the number and morphometrical parameters of the nucleus ambiguous neurons after the injury and regeneration of the recurrent laryngeal nerve in the rat]. / Estudio del número de neuronas del núcleo ambiguo y sus parámetros morfométricos tras lesión y regeneración del nervio laríngeo recurrente de la rata.

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. We studied a control group of 14 animals and four experimental groups of between 10 and 16 animals each one. In the experimental groups we studied the regeneration of the axotomized nerve in four different intervals of time after the injury: 21-28 days, 42-60 days, 90-120 days, and 150-180 days. In the control group we traced the RLN without injury while in the experimental groups we traced the axotomized RLN after each regeneration interval. RESULTS: The number of traced neurons in the control group was 143 +/- 38; in the experimental groups the number was always lower than in the control (21-28 days: 14 +/- 23 neurons; 42-60 days: 46 +/- 49; 90-120 days: 55 +/- 57; 150-180 days: 61 +/- 60). The morphologic parameters studied within the neuronal bodies in the experimental groups were no statistically different when compared with those in the control group. CONCLUSIONS: Results show that the tracing of the RLN after its axotomy and regeneration, in the adult rat, involves a decrease in the number of traced neurons within the NA but no changes in their size or shape during the analysed periods.

Anatomical variations of the renal arteries: Cadaveric and radiologic study, review of the literature, and proposal of a new classification of clinical interest.

PURPOSE: To analyse the variations of the renal arteries in two samples, cadaveric and computerized tomographic (CT) images, as well as to propose a simple classification of such variations based on the obtained results and an extensive review of the literature on the topic. MATERIAL AND METHODS: Sixty human dissected kidneys and their vessels, and 583 abdominal CT were studied. RESULTS: A total of 86 arteries were described in the cadaveric sample, whereas 1223 were analysed in the radiological one. Five types (a-e) and patterns (I-V) have been stablished in the classification. Type a, aortic hilar artery, incidences were 79% in cadavers and 95% in CT; Type b, hilar upper polar artery, incidences were 10% in cadavers and 2% in CT; Type c, aortic upper polar artery, incidences were 5% in cadavers and 2% in CT; Type d, aortic lower polar artery, incidences were 3% in cadavers and 1% in CT; Type e, hilar lower polar artery, incidences were 2% in cadaver and less than 0.1% in CT. The pattern represents the number of arteries reaching one kidney. Patterns I-IV were found in cadavers (I: 78%; II: 19%; III and IV: 2%); in CT sample only patterns I (88%) and II (12%). Pattern V was added because it has been described in the reviewed literature. CONCLUSIONS: Type a and pattern I are the most prevalent, both in the cadaveric and the CT samples. Also in the consulted literature. There are no differences in the types and pattern incidences by side or sex. A simple, comprehensive and useful classification is proposed.

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. After several survival periods (1, 2, 4, 8, 12, 16 weeks; at least six rats at each time point) the posterior cricoarytenoid (PCA) and thyroarytenoid (TA) muscles were injected with fluorescent-conjugated cholera toxin and the motility of the vocal folds evaluated. After section and subsequent repair of the RLN, no movement of the vocal folds could be detected at any of the survival times studied and the somatotopy and the number of labeled motoneurons changed. From 4 wpi award, the somatotopy was significantly disorganized, with the PCA motoneurons being located rostrally relative to their normal location. A rostrocaudal overlap between the two pools of motoneurons supplying the PCA and TA muscles was observed from 2 wpi onwards. Hardly any labeled neurons were found in the contralateral Amb in any of the experimental groups. An injury of the RLN leads to a reinnervation of the denervated motor endplates of PCA and TA. However, misdirected axons sprout and regrowth from the proximal stump to the larynx. As a result, misplaced innervation of muscles results in a lack of functional recovery of the laryngeal folds movement following a RLN injury.

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. The B subunit of the cholera toxin was employed as a retrograde tracer to determine the locations, within the nucleus ambiguus, of the neurons of these intrinsic laryngeal muscles following intramuscular injection. The labelled neurons were found ipsilaterally in the nucleus ambiguus grouped in discrete populations with reproducible rostrocaudal and dorsoventral locations among the sample of animals. Neurons innervating the cricothyroid muscle were located the most rostral of the three populations, neurons innervating the posterior cricoarytenoid were found more caudal, though there was a region of rostrocaudal overlap between these two populations. The most caudal were the neurons innervating the thyroarytenoid muscle, presenting a variable degree of overlap with the posterior cricoarytenoid muscle. The mean number (±SD) of labelled neurons was found to be 41 ± 9 for the cricothyroid, 39 ± 10 for the posterior cricoarytenoid and 33 ± 12 for the thyroarytenoid.