A new type of the coracobrachialis muscle.

The coracobrachialis muscle belongs to the anterior group of the brachial region. Its main functions are flexion and adduction at the glenohumeral joint. It is highly morphologically variable, especially in the number of bellies, place of origin or insertion, and its relationship to the musculocutaneous nerve. Accessory structures associated with the coracobrachialis muscle include the coracobrachialis brevis or coracobrachialis longus muscle. The present case describes a three-headed coracobrachialis muscle with two such additional structures. One of these has a tendinous origin connected to the periosteum and located on the surgical neck of the humerus. Its insertion is fused with the third head of the coracobrachialis muscle. The other has a proximal attachment fused with the capsule of the shoulder joint, and its distal attachment is fused with the third head of the coracobrachialis muscle in place of its connection with the short head of the biceps brachii. This could result in better stabilisation of the glenohumeral joint; on the other hand, it could limit operational access during treatment of subscapularis tears.

Predictive value of magnetic resonance for identifying neurovascular compressions in trigeminal neuralgia. / Valor predictivo de la resonancia magnética para la identificación de compresiones neurovasculares en la neuralgia del trigémino.

INTRODUCTION: Microvascular decompression (MVD) is accepted as the only aetiological surgical treatment for refractory classic trigeminal neuralgia (TN). There is therefore increasing interest in establishing the diagnostic and prognostic value of identifying neurovascular compressions (NVC) using preoperative high-resolution three-dimensional magnetic resonance (MRI) in patients with classic TN who are candidates for surgery. METHODS: This observational study includes a series of 74 consecutive patients with classic TN treated with MVD. All patients underwent a preoperative three-dimensional high-resolution MRI with DRIVE sequences to diagnose presence of NVC, as well as the degree, cause, and location of compressions. MRI results were analysed by doctors blinded to surgical findings and subsequently compared to those findings. After a minimum follow-up time of six months, we assessed the surgical outcome and graded it on the Barrow Neurological Institute pain intensity score (BNI score). The prognostic value of the preoperative MRI was estimated using binary logistic regression. RESULTS: Preoperative DRIVE MRI sequences showed a sensitivity of 95% and a specificity of 87%, with a 98% positive predictive value and a 70% negative predictive value. Moreover, Cohen's kappa (CK) indicated a good level of agreement between radiological and surgical findings regarding presence of NVC (CK 0.75), type of compression (CK 0.74) and the site of compression (CK 0.72), with only moderate agreement as to the degree of compression (CK 0.48). After a mean follow-up of 29 months (range 6-100 months), 81% of the patients reported pain control with or without medication (BNI score i-iiiI). Patients with an excellent surgical outcome, i.e. without pain and off medication (BNI score i), made up 66% of the total at the end of follow-up. Univariate analysis using binary logistic regression showed that a diagnosis of NVC on the preoperative MRI was a favorable prognostic factor that significantly increased the odds of obtaining an excellent outcome (OR 0.17, 95% CI 0.04-0.72; P=.02) or an acceptable outcome (OR 0.16, 95% CI 0.04-0.68; P=.01) after MVD. CONCLUSIONS: DRIVE MRI shows high sensitivity and specificity for diagnosing NVC in patients with refractory classic TN and who are candidates for MVD. The finding of NVC on preoperative MRI is a good prognostic factor for long-term pain relief with MVD.

The superior mesenteric artery and the variations of the colic patterns. A new anatomical and radiological classification of the colic arteries.

The superior mesenteric artery (SMA) supplies irrigation to the small intestine, ascending and a variable area of the transverse colon. Although medical imaging and surgical procedures have been widely developed in the last decades, the anatomy of the SMA using advanced imaging technology remains to be elucidated. Previous studies have used small sample sizes of cadaveric or radiological samples to propose a number of classifications for the SMA. In this study, we aimed to provide a more detailed description and useful classification of the SMA and its main branches [middle colic artery (MCA), right colic artery (RCA), and ileocolic artery (ICA)]. Samples (n = 50, 28 males and 22 females) were obtained from the repository of human cadavers located at the Department of Human Anatomy and Embryology, Complutense University of Madrid. This sample was dissected by preclinical medical students and completed by two of the authors (Gamo and Jiménez). A second set of samples was obtained from a bank of computerized tomography (CT) (560 CTs, 399 males and 161 females) collected by the Radiology Department at the Clínico San Carlos Hospital, Spain. Based on the results obtained from these studies, we propose a new classification of four patterns for the SMA anatomy. Pattern I as the independent origin of the three main branches of the SMA (cadaveric 40 %; CT 73.69 %); Pattern II is subdivided in three sub-patterns based on the common trunks of origin: Pattern IIa, common trunk between RCA and MCA (cadaveric 20 %, CT 4.28 %); Pattern IIb, common trunk between RCA and ICA (cadaveric 32 %, CT 15 %); Pattern IIc, common trunk for the three main branches (cadaveric 0 %, CT 0.35 %); Pattern III, as the absence of RCA (cadaveric 8 %; CT 2.32 %) and Pattern IV, based on presence of accessory arteries (not found in any of the samples). Although the independent origin of the three colic arteries have been classically described as the most frequent, the right colic artery is responsible of major variations.

The peroneocuboid joint: morphogenesis and anatomical study.

The peroneocuboid joint, between the peroneus longus tendon and the cuboid bone, has not been anatomically well-defined and no embryological study has been published. Furthermore, the ossification of the os peroneum (a sesamoid inside the peroneus longus tendon) and its associated pathology has been considered to be generated by orthostatic and/or mechanical loads. A light microscopy analysis of serially sectioned human embryonic and fetal feet, the analysis of human adult feet by means of standard macroscopic dissection, X-ray and histological techniques have been carried out. The peroneus longus tendon was fully visible until its insertion in the 1st metatarsal bone already at embryonic stage 23 (56-57 days). The peroneocuboid joint cavity appeared at the transition of the embryonic to the fetal period (8-9th week of gestation) and was independent of the proximal synovial sheath. The joint cavity extended from the level of the calcaneocuboid joint all the way to the insertion of the peroneus longus tendon in the 1st metatarsal bone. The frenular ligaments, fixing the peroneus longus tendon to the 5th metatarsal bone or the long calcaneocuboid ligament, developed in the embryonic period. The peroneus longus tendon presented a thickening in the area surrounding the cuboid bone as early as the fetal period. This thickening may be considered the precursor of the os peroneum and was similar in shape and in size relation to the tendon, to the os peroneum observed in adults. To the best of our knowledge, this is the first study to show that the os peroneum, articular facets of the peroneus longus tendon and cuboid bone, the peroneocuboid joint and the frenular ligaments appear during the embryonic/fetal development period and therefore they can not be generated exclusively by orthostatic and mechanical forces or pathological processes.

Variations of the radial recurrent artery of clinical interest.

PURPOSE: The anatomy of the radial recurrent artery (RRA) is important for different clinical procedures: interventional cardiology and microsurgery of the forearm; however, few studies have analysed its morphology: number, course, relations and distribution. METHODS: The RRA was analysed in 332 upper limbs divided into two groups: (1) normal pattern of the arterial axis of the upper limb (266 cases), (2) associated with major arterial variations (66 cases). RESULTS: A second or accessory RRA existed in 31.2 % in group 1, and 30.3 % in group 2. In both groups, the second RRA originated from the brachial (100 %) and always (100 %) coursed behind the bicipital tendon. The accessory RRA supplied the brachioradialis, brachialis and biceps brachii muscles. The RRA in group 1, originated mostly from the radial artery (75 %), followed by radioulnar division and ulno-interosseous trunk. In group 2, the RRA arise from the brachioradial artery (65 %), or from the radial artery (in cases of ulnar or brachial artery variation). The course of the RRA behind the biceps brachii tendon was observed in 9.4 % of group 1 and in 6.1 % of group 2. The RRA supplied the brachioradialis, extensor carpi radialis longus and brevis, and supinator muscles. The RRA and accessory RRA anastomosed forming a ring around the biceps brachii tendon in 0.75 % in group 1 and in 13.6 % in group 2, the latter group having an important clinical interest. CONCLUSIONS: The variability of the RRA may provide an advantage for microsurgical procedures of the elbow and disadvantage during transradial catheterism.

[Central projections of the rat recurrent laryngeal nerve]. / Proyecciones centrales del nervio laríngeo recurrente de la rata.

Laryngeal nerves contain the fibres that control the laryngeal function. The studies carried out on the rat with the purpose of having a better knowledge of the functional components and the real origin of the fibres conveyed by the recurrent laryngeal nerve (RLN) are few and in disagreement. No one of such papers were developed using biotinylated dextrane amines (BDA), a powerful tool for tracing neural pathways. The aim of our study was to identify in the rat using BDA, the nuclei of real origin of the fibres of the RLN, knowing in this way the functional components of this nerve. The study has been developed in 31 adult male Sprague-Dawley rats, applying the BDA into the lesioned RLN. The results obtained in all the animals show that the rat's RLN does not contain afferent fibres, whereas the efferent fibres were originated within the ipsilateral nucleus ambiguus (NA). So, in the rat, the RLN seems to contain exclusively efferent fibres, probably been the superior laryngeal nerve who conveyed the afferent fibres.

[Morphometry of the recurrent laryngeal nerves of the rat]. / Morfometría de los nervios laríngeos recurrentes de la rata.

In mammals the recurrent laryngeal nerves are dissimilar in length between both sides. This asymmetry involves different time of arrival of the stimulus to the laryngeal musculature controlled by each nerve. Thus, several explanations have been addressed to elucidate the closest of the glottis at the same time despite the unlike length of the nerves. However, previous works on the topic lack of several important data. The present study compares, in two groups of 10 and 6 rats, the length and the composition of myelinated fibers in the recurrent laryngeal nerves of both sides, by means of light microscopy and a computerized morphometric analysis. The results show a mean difference of 0,84 cm longer the left than the right recurrent laryngeal nerve. No statistical differences were observed in the number of myelinated fibers between both sides. However, the myelinated fibers of the right side were statistically bigger in diameter than the fibers of the left side. The data are discussed in the context of the mechanisms for the compensation of the dissimilar length of both recurrent laryngeal nerves.

A rare case of a four-headed biceps brachii muscle with a double piercing by the musculocutaneous nerve.

A rare case of a four-headed biceps brachii muscle associated with a double piercing of one of the supernumerary heads by the musculocutaneous nerve was observed in the right arm of an 87-year-old female cadaver. One of the supernumerary heads of the biceps brachii originated from the humerus, in the area between the lesser tubercle and the coracobrachialis and brachialis muscles and joined the long head at the level where the latter joined the short head. The second supernumerary head originated from the humerus at the point where the coracobrachialis muscle inserted and joined the biceps brachii tendon and its bicipital aponeurosis at the inferior third of the arm. The musculocutaneous nerve originated from the lateral cord of the brachial plexus and, after piercing the coracobrachialis muscle, coursed along one of the supernumerary heads of the biceps brachii muscle before piercing it from deep to superficial and then again from superficial to deep. It then adopted its normal position between the biceps brachii and brachialis muscles before exiting in the lateral aspect of the arm and continuing as the lateral cutaneous nerve of the forearm.

Development of the arterial pattern in the upper limb of staged human embryos: normal development and anatomic variations.

A total of 112 human embryos (224 upper limbs) between stages 12 and 23 of development were examined. It was observed that formation of the arterial system in the upper limb takes place as a dual process. An initial capillary plexus appears from the dorsal aorta during stage 12 and develops at the same rate as the limb. At stage 13, the capillary plexus begins a maturation process involving the enlargement and differentiation of selected parts. This remodelling process starts in the aorta and continues in a proximal to distal sequence. By stage 15 the differentiation has reached the subclavian and axillary arteries, by stage 17 it has reached the brachial artery as far as the elbow, by stage 18 it has reached the forearm arteries except for the distal part of the radial, and finally by stage 21 the whole arterial pattern is present in its definitive morphology. This differentiation process parallels the development of the skeletal system chronologically. A number of arterial variations were observed, and classified as follows: superficial brachial (7.7%), accessory brachial (0.6%). brachioradial (14%), superficial brachioulnar (4.7%), superficial brachioulnoradial (0.7%), palmar pattern of the median (18.7%) and superficial brachiomedian (0.7%) arteries. They were observed in embryos belonging to stages 17-23 and were not related to a specific stage of development. Statistical comparison with the rates of variations reported in adults did not show significant differences. It is suggested that the variations arise through the persistence, enlargement and differentiation of parts of the initial network which would normally remain as capillaries or even regress.

[Glottic immobility: retrospective study of 229 cases]. / Inmovilidad glótica: estudio retrospectivo de 229 casos.

A retrospective study of the unilateral and bilateral vocal fold immobility cases diagnosed at our hospital between 1985 and 1998 was carried out. Of the 229 cases studied, vocal fold immobility was bilateral in 58 patients (25%), unilateral right in 60 (26%), and unilateral left 111 (49%). The most frequent etiologies in the bilateral cases were thyroid surgery (38%) and prolonged intubation (31%); idiopathic cases (32%) and thyroid surgery (23%) in the unilateral right cases; and idiopathic cases (28%) and extralaryngeal tumors (22%) in the unilateral left cases. Clinical compensation was achieved in more than 85% of cases of unilateral immobility when the etiology was idiopathic or due to surgical damage to the recurrent or vagus nerves, 70% when it was a prolonged intubation, 56% in neurological patients and 38% in extralaryngeal tumors. In patients with bilateral vocal fold immobility, 14% did not require any treatment, 34% had a permanent tracheostomy, and 52% recovered adequate naso-oral ventilation after surgery (tracheostomy only in 12 patients and arytenoidectomy in 18 patients).

The acetabular point: a morphological and ontogenetic study.

The acetabular point was analysed by studying human pelvic bones from 326 individuals ranging from newborns to age 97 y. The bones were categorised into 3 groups according to the degree of fusion for the 3 elements of the pelvis: nonfused (59), semifused (5) and fused (262). The acetabular point in immature pelvic bones is clearly represented by the point of the fusion lines for each bony element at the level of the acetabular fossa. In adult pelvic bones the acetabular fossa has an irregular clover-leaf shape, the superior lobe being smaller than the anterior and posterior lobes. Cross-sectional analysis of acetabular morphology suggested that the acetabular point in adult pelvic bones is always represented by the indentation between the superior and the anterior lobes of the acetabular fossa.

Variations of the arterial pattern in the upper limb revisited: a morphological and statistical study, with a review of the literature.

A total of 192 embalmed cadavers were examined in order to present a detailed study of arterial variations in the upper limb and a meta-analysis of them. The variable terminology previously used was unified into a homogenous and complete classification, with 12 categories covering all the previously reported variant patterns of the arm and forearm.

Median artery revisited.

This study confirms that the median artery may persist in adult life in 2 different patterns, palmar and antebrachial, based on their vascular territory. The palmar type, which represents the embryonic pattern, is large, long and reaches the palm. The antebrachial type,which represents a partial regression of the embryonic artery is slender, short, and terminates before reaching the wrist. These 2 arterial patterns appear with a different incidence. The palmar pattern was studied in the whole sample (120 cadavers) and had an incidence of 20%, being more frequent in females than in males (1.3:1), occurring unilaterally more often than bilaterally (4:1) and slightly more frequently on the right than on the left (1.1:1). The antebrachial pattern was studied in only 79 cadavers and had an incidence of 76%, being more frequent in females than in males (1.6:1); it was commoner unilaterally than bilaterally (1.5:1) and was again slightly more prevalent on the right than on the left (1.2:1). The origin of the median artery was variable in both patterns. The palmar type most frequently arose from the caudal angle between the ulnar artery and its common interosseous trunk (59%). The antebrachial pattern most frequently originated from the anterior interosseous artery (55%). Other origins, for both patterns, were from the ulnar artery or from the common interosseous trunk. The median artery in the antebrachial pattern terminated in the upper third (74%) or in the distal third of the forearm (26%). However, the palmar pattern ended as the 1st, 2nd or 1st and 2nd common digital arteries (65%) or joined the superficial palmar arch (35%). The median artery passed either anterior (67%) or posterior (25%) to the anterior interosseous nerve. It pierced the median nerve in the upper third of the forearm in 41% of cases with the palmar pattern and in none of the antebrachial cases. In 1 case the artery pierced both the anterior interosseous and median nerves.

An anatomical study of anastomoses between the laryngeal nerves.

OBJECTIVE: To systematize the anatomy of the connecting branches between laryngeal nerves. METHODS: Microdissection of 90 larynges obtained from necropsies (57 men and 33 women; age range, 41-95 y). RESULTS: Anastomoses between the internal and recurrent nerves appeared in four different patterns: 1) Galen's anastomosis, as the connection between the dorsal branches of both nerves (100%); 2) arytenoid plexus, as the connection between the arytenoid branches of both nerves, in relation with the arytenoid muscle, and divided in a deep part (100%) and a superficial part (86%); 3) cricoid anastomosis, previously only described in cows, located in the front of the cricoid lamina (6/10 cases); and 4) thyroarytenoid anastomosis, as the connection of a descending branch of the internal laryngeal nerve and an ascending branch of the recurrent nerve (14%). Anastomosis between the internal laryngeal and the external laryngeal nerves appeared as a connecting branch throughout the foramen thyroideum (21%). Anastomosis between the external laryngeal and recurrent nerves appeared as a connecting branch throughout the cricothyroid muscle (68%). CONCLUSION: At least two anastomoses (Galen's anastomosis and arytenoid plexus) appeared in 21% of hemilarynges, and 79% of cases had three or more anastomoses between the laryngeal nerves. The different prevalence of this complex anastomotic pattern suggests functional differences in the sensory and motor innervation of individual subjects.

[Differential features of transglottic carcinoma]. / Características diferenciales de los carcinomas transglóticos.

A study was made of the differential features of transglottic laryngeal carcinomas. We made a retrospective study of patients with laryngeal carcinoma diagnosed in our center from 1985 to 1996. In this period, 1212 laryngeal carcinomas were diagnosed, of which 99 (8%) were considered transglottic. In relation to factors such as sex, toxic habits, level of histological differentiation or affected nodes, patients with transglottic carcinomas had characteristics that were intermediate between patients with glottic and supraglottic carcinomas. An analysis was made of the treatments and the results obtained in patients treated with radical intention and a minimum follow-up of 3 years. The treatment most frequently used in patients with transglottic carcinoma was surgery (total laryngectomy) and complementary radiotherapy. The 5-year actuarial adjusted survival rate jor patients with transglottic carcinoma was 78%, which was intermediate between the survival rates of patients with glottic (90%) or supraglottic (69%) carcinoma.

Intracranial course and relations of the hypoglossal nerve. An anatomic study.

This anatomic study describes the course and intracranial relations of the hypoglossal n. in 32 cadavers. The rootlets of the nerve emerged as a fan-shaped distribution (23.44%) or in two bundles (76.56%) and converged towards the hypoglossal canal in the subarachnoid space before piercing the duramater. In 76.57% of cases the rootlets pierced the dura mater in two separate apertures, less commonly through the same aperture (21.87%), and in rare cases through three individual apertures, as in one of our cases. The distance between the two apertures varied from 0.6 mm to 8.7 mm. Commonly, the two bundles converged together and left the skull through one foramen in the skull. However, in some cases (28.12%), the hypoglossal canal was divided in two by a small bony spicule. In 23.45% of cases the initial course of the posterior inferior cerebellar a. (PICA) passed between the two bundles of the hypoglossal n. before ascending towards the lateral border of the fourth ventricle.

Right coronary artery arising from the left aortic sinus in a heart with left coronary dominance: a post-mortem description--a case report.

The authors report the post-mortem description of the coronary arterial circulation of an 81-year-old man. The heart showed a concordant atrioventricular and ventricle-arterial disposition. The coronary artery distribution presented left dominance. No myocardial scars were observed. The ostium of the right coronary artery (RCA) was located in the left aortic sinus just in front of the opening of the left coronary artery. The ostium was slit-like and its maximum diameter was 5 mm. The RCA began between the aorta and the pulmonary trunk and ended as a small right marginal artery. The absence of heart disease and the man's survival until an advanced age were probably due to the fact that the RCA supplied only a small portion of the right ventricle, given the left coronary dominance.