[Anatomy of the pelvic lymphatic system]. / Anatomie du système lymphatique pelvien.

The lymphatic system of the pelvis collects the lymph of the genital and urinary organs and of the digestive tract. It is formed by lymphatic nodes and vessels situated inside the conjunctive tissue, near the organs (visceral lymphatic nodes) but especially along the external, internal and common iliac vessels (iliac lymphatic nodes). These nodes receive afferent vessels issued from the different pelvic organs. From the iliac lymphnodes arise efferent vessels running towards lymphatic collectors, situated above them, and which end in the lymphatic lombar duct. The lymphatic pathways represent the preferential way of scattering of cancerous cells. Therefore, the knowledge of the anatomy, of the situation and of the draining of the nodes is of the utmost importance in the evaluation of a cancer of a pelvic organ.

Scaphotrapezial ligament: normal arthro-CT and arthro-MRI appearance with anatomical and clinical correlation.

The purpose of our study was to demonstrate and describe the MR and arthro-CT anatomic appearance of the scaphotrapezial ligament and illustrate some of the pathologies involving this structure. This ligament consists of two slips that originate from the radiopalmar aspect of the scaphoid tuberosity and extend distally, forming a V shape. The ulnar fibers, which are just radial to the flexor carpi radialis sheath, inserted along the trapezial ridge. The radial fibers were found to be thinner and inserted at the radial aspect of the trapezium. Twelve fresh cadaver wrists were dissected, with close attention paid to the scaphotrapezio-trapezoidal (STT) joint. An osseoligamentous specimen was dissected with removal of all musculotendinous structures around the STT joint and was performed with high-resolution acquisition in a 128-MDCT scanner. Samples of the wrist area were collected from two fetal specimens. A retrospective study of 55 patients with wrist pain that were submitted to arthrography, arthro-CT, and arthro-MRI imaging was performed (10 patients on a 3-T superconducting magnet and 45 patients on a 1.5-T system). Another ten patients had high-resolution images on a 3-T superconducting magnet without arthrographic injection. MR arthrography and arthro-CT improved visualization and provided detailed information about the anatomy of the scaphotrapezial ligament. Knowledge of the appearance of this normal ligament on MRI allows accurate diagnosis of lesions and will aid when surgery is indicated or may have a role in avoiding unnecessary immobilization.

[The spinal canal: from imaging anatomy to diagnosis]. / Espaces rachidiens intracanalaires: de l'anatomie radiologique au diagnostic étiologique.

The spinal canal is divided into epidural, subdural and subarachnoid spaces. Intraspinal processes should be correctly placed into their space of origin. MRI is the best imaging modality to achieve this task. Accurate determination of the space of origin routinely requires the acquisition of two different pulse sequences, typically T1W and T2W images, in two orthogonal planes, usually axial and sagittal. Simple imaging features can assist in determining the site of origin: changes to the epidural fat, compression or widening of subarachnoid spaces. The epidural space, bordered medially by dura, contains fat and vascular structures. The subdural space is a virtual space in between the dura and arachnoid membrane. The subarachnoid space is home to the CSF, spinal cord and nerve rootlets. An epidural process replaces the epidural fat, displaces the dura and narrows the subarachnoid space. A subarachnoid process widens the subarachnoid space and spares the epidural fat. Epidural processes usually are infectious or tumoral, either primary or secondary to spinal involvement. Subarachnoid processes include primary tumors, leptomeningeal metastases, arachnoiditis and hemorrhage. Nerve sheath tumors and meningiomas are the most frequent intradural extramedullary tumors.

Is the high submandibular transmasseteric approach to the mandibular condyle safe for the inferior buccal branch?

PURPOSE: There are basically 3 main approaches for extra-articular mandibular condyle fractures: low cervical, retromandibular and preauricular. These include a risk of facial palsy affecting the marginal mandibular branch. We use a high submandibular transmasseteric approach featuring masseter section 10-20 mm above the mandibular basilar edge. Our null hypothesis was that both the marginal mandibular and the inferior buccal branches are not more at risk than in other surgical approaches. METHODS: This study was based on 20 parotidomasseteric dissections from 10 embalmed cadaveric heads. We used as reference the vertical line, passing through the mandibular angle, parallel to the preauricular line. We performed measurements of the marginal mandibular and inferior buccal branches' heights. RESULTS: The inferior buccal branch had an average height of 16.8 mm and the highest standard deviation (7.2). Extremes were, respectively, 32 and 7 mm. The marginal mandibular branch had an average height of 3.2 mm with standard deviation equal to 3.0. Extremes were, respectively, 9 and -3 mm. CONCLUSION: The high submandibular transmasseteric approach provides great exposure of facial nerve branches lying on the masseter muscle, if even encountered. Through masseteric incision performed between 10 and 20 mm above the basilar edge of the mandible, the marginal mandibular branch is safe from wound with an added safety margin of 4 mm. The surgeon using this approach is most likely to encounter the inferior buccal branch. It can then be avoided under visual control. This makes it a swift and safe approach to the mandibular condyle.

The laryngeal fat body.

AIM: To describe the anatomy and topography of the laryngeal fat body and of the space it lies within. MATERIALS AND METHODS: The study is carried out on series of histological sections of head and neck blocks from six foetuses and three newborns. Three adult necks were dissected, a fourth one analysed through sagittal median section. CT-Scan and MRI imaging complete the description. RESULTS: The laryngeal fat body (LFB) lies within the pre-epiglottic (PE) space that stands in the median anterior part of the upper infrahyoid region, located just below the level of the hyoid bone. The walls of the PE space are: superior (base), anterior lateral right and left, posterior, inferior (apex). This space is divided into two compartments by a median septum. The LFB consists in a rather pure fat, structured in large polyhedral lobules. It shows no limiting capsule. DISCUSSION: Dissection-based description of the PE space made in literature matches ours conducted on series of histological sections. All authors agree on the fat content of the space but some of them find a capsule around the LFB that we did not observe on our histological sections. CT-Scan and MRI imaging are accurate for analysis of these structures and of similar efficiency. The study of the LFB should be considered regarding the one of other fat bodies in the human body. CONCLUSION: Anatomical knowledge of the PE space and its content, the LFB, is important, as alteration of their morphology is the early witness of neighbouring carcinological extension.

Frohse's arcade is not the exclusive compression site of the radial nerve in its tunnel.

INTRODUCTION: The radial tunnel is a musculo-aponeurotic furrow which extends from the lateral epicondyle of humerus to the distal edge of the supinator muscle. The superficial head of the supinator muscle forms a fibrous arch, the arcade of Frohse (AF), which is the most common site of compression of the radial nerve motor branch. The latter is less commonly compressed by the adjacent muscular structures. This tunnel syndrome might be worsened with repeated pronation and supination of the forearm. The double object of that work was: (1) to define the radial nerve anatomic landmarks, (2) to determine the anatomical relationship of the radial nerve main trunk and branches to the peripheral osseous and muscular structures in the anterior aspect of the elbow joint in order to identify which of these conflicting elements are likely to cause a compressive neuropathy. MATERIAL AND METHODS: The study design involved the dissection of 30 embalmed cadaveric upper limbs. Anatomic and morphometric investigations of the radial nerve, its terminal and motor branches were carried out. The presence of adhesions between radial nerve and joint capsule, tendons and aponeurotic expansions of epicondylar muscles and supinator arch was investigated. All measurements were taken in both pronation and supination of the forearm. RESULTS: Neither macroscopic radial compressive neuropathy at the level of the supinator arch nor adhesions between the radial nerve and the joint capsule were found. In four cases (13%), dense fibrous tissue surrounded the radial nerve supply to extensor carpi radialis brevis (ECRB). The fibrous arch of the supinator muscle arose in a semi-circular manner and was noted to be tendinous in 87% of the extremities and of membranous consistency in the remaining 13%. The length of the AF averaged 25.9 mm. The angle formed by the radial shaft and the supinator arch was 23 degrees. Neither fibrous structures nor adhesions of the deep branch of the radial nerve (DBRN) along its course through the supinator muscle were observed. DISCUSSION: Anatomic studies have revealed a variable rate of occurrence of a tendinous AF, which range from 30 to 80% (87% in our study) according to authors. It is reported to be a predisposing factor to the development of chronic entrapment neuropathy of the DBRN, especially if it is thick and provides a narrow opening for passage of the DBRN. The tendinous consistency of the supinator arch is believed to develop in adults, in response to repeated rotary movements of the forearm. Repetitive pronation and supination of the forearm induces compression of the radial nerve and its branches between two inextensible structures. The fibrous AF and the proximal end of the radius (radial head and radial tubercle). This condition is aggravated by the supinator muscle repeated activity. Repetitive compression might then promote histological changes in radial tunnel content and progressive development of a local fibrous zone. We also observed that the radial nerve supply to ECRB could be entrapped between the superolateral aspect of the ECRB and the superior edge of the supinator muscle.

Relationships of the musculocutaneous nerve and the coracobrachialis during coracoid abutment procedure (Latarjet procedure).

PURPOSE: The aim of this study was first to define first the anatomical relationships between the musculocutaneous nerve and the coracobrachialis, and then the induced modifications of these relationships by a preglenoid transposition of the vertical part of the coracoid process. MATERIALS AND METHODS: Twenty-one embalmed adult trunks and upper limb were dissected. First the coracobrachialis and the musculocutaneous nerve were identified through a deltopectoral approach. We measured the distances between the lateral cord of the brachial plexus and the entry point of the nerve, between the inferior tip of the tip of the coracoid process and the penetration of the nerve or its twigs, and finally the angle between the general axis of the coracobrachialis and the axis of the musculocutaneous nerve. The same measures were performed after the coracoid bone block abutment. RESULTS: Proximal motor branches destined to the coracobrachialis varied from 0 to 3. Mean distance between the lateral cord of the brachial plexus and entry point of the nerve into the muscle was 47.2 mm before and 48.43 mm after the coracoid transfer. Mean angulations between the nerve and the muscle was 121 degrees before and 136 degrees after the transfer of the coracoid process. Mean distance between the inferior tip of the coracoid process and entry point of the nerve into the muscle was 55.7 mm, reduced to 48.6 mm after the coracoid transposition. Finally, the distance between the tip of the coracoid and the first motor twig entering the coracobrachialis was less than 50 mm in 75% of the cases with a mean value of 40.6 mm. CONCLUSIONS: Lesion of the musculocutaneous nerve is a known complication of the coracoid bone block abutment procedure (Latarjet-Bristow). From this study we know that they are due to lengthening of the nerve and modification of the penetration angle of the nerve into the coracobrachialis. We also infer that some motor nerve destined to the coracobrachialis might be damaged during the proximal medial release of the muscle after the detachment of the pectoralis minor muscle.

New findings on intermetacarpal fat pads: anatomy and imaging.

Many studies have focused on the functional importance of the gliding structures of the hand. These structures are clinically important in reconstructive surgery and mechanically essential for an efficient hand grasp. The aims of this study were to first review the intermetacarpal space and then focus on its fatty tissue, the intermetacarpal fat pad. This study used dissections and histological analysis of fetal and adult hands and CT scans of adult hands. The intermetacarpal fat pads are well-defined adipose structures located between the heads of the second, third, fourth and fifth metacarpal bones. They are located in spaces defined by the palmar fascia and its deep expansions. These spaces are closed distally but open proximally into the tunnels surrounding the flexor tendons (Legueu and Juvara canals). The pads are composed of non-mobilizable fat; they protect the neurovascular pedicles of the fingers. They may act with the palmar skin to mitigate compressive and shear forces during gripping. Finally they may be involved in neurological symptoms if their size is increased by any trauma or inflammatory process.

Microvascularisation of the male urethra in neonates and infants.

The microvascularisation of the male urethra was studied in neonates and infants by injection of agarised China ink into the circulation. The purpose of this study was to specify the angioarchitecture of each tunic of the urethral wall. The disposition of the microvascularisation networks varies depending on the urethral parts considered: only the mucous membrane networks are uniform throughout the entire urethra. The sub-mucous networks are significantly increased in the spongy part. The muscular networks disappear in the spongy part.

The lumbo-gluteal adipose body.

The lumbo-gluteal adipose body (LGAB) is a well-delineated fatty structure, in the lumbo-gluteal trigone, encroaching on the upper part of the gluteal region and flank. The aim of this study was to compare the gross and histological anatomy of the LGAB with that of other well-defined adipose bodies of the human body. The macroscopic study using dissections and slices in the main three planes in adults was supplemented by microscopic study of histological slices taken from fetuses and neonates. The forms and limits of the LGAB are defined, along with its structure. The LGAB appears to act as a filling structure, lining the hypodermis in the regions that it covers.

Microvascularization of the female urethra in fetuses, neonates and infants.

The microvascularization of the female urethra was studied in fetuses, neonates and infants by injection of agarized China ink into the circulation. The purpose of this study was to specify the angioarchitecture of each tunic and their specific drainage. The disposition of the microvascularization of the urethra is superimposed on the orientation of the fibers of the muscular tunic. The orientation of the veins of the sub-mucous tunic is longitudinal and not plexiform.

Microvascularization of the mucocutaneous junction of the nose.

The aim of this study was to describe the microvascularization of the area of junction located between the integuments of the nasal ala and the respiratory mucosa. This study is part of an overall study on the microvascularization of the mucocutaneous junctions of the head. It was undertaken on histological or clarified sections of noses from fetuses, newborns and adults whose vascular system was injected with Indian ink agar. The mucocutaneous junction of the nose shows similarities with the mucocutaneous junction of the oral cavity. Under a well-defined avascular and thick epithelium lies a vascular papillary network with typical loops less high than in the lips. The angioarchitectonics of superficial and deep vascular reticular networks is similar to that of the lips but they are less dense.

Microvascularization of the mucocutaneous junction of the eyelid in fetuses and neonates.

The aim of this study was to specify the microvascularization of the junctional region between the integuments of the superficial surface of the free margin of the eyelid and the palpebral conjunctival mucosa. The study was carried out using histological or transparified slices of upper and lower eyelids taken from fetuses and neonates, in which the vascular system was injected with agarized China ink. The mucocutaneous junction of the eyelid is located at the posterior border of the free margin and extends to its deep surface. It has vascular similarities to the oral cavity and the nasal pyramid. Under a thickened avascular epithelium, there is a papillary network composed of characteristic loops that are less raised than in the lips but more developed than in the nose. The superficial and deep vascular reticular networks are comparable in fundamental arrangement to those of other junctional zones. Thus, the palpebral mucocutaneous junction shows cutaneous-type microvascularization, just like the other junctional zones of the head.

Microvascularization of the mucocutaneous junctions of the head in fetuses and neonates.

The mucocutaneous junctions of the head (oral, nasal and palpebral) are transitional zones between the integuments and the mucosa. Their microvascularization is studied in the heads of fetuses and neonates by injection of agarized China ink into the vascular system. These zones are situated deep with respect to the free edge of the oral or nasal cavity or relative to the free margin of the eyelid. They present cutaneous-type microvascularization with a papillary network and reticular networks. Long capillary loops connected to the deep reticular network are their main feature. In the lips and eyelids, the morphology of the networks and their relationship with the orbicular muscles are suggestive of a functional structure.

Adipose body of the orbit.

The adipose body of the orbit (ABO) fills most of the orbital cavity, surrounding the eyeball, muscles, nerves, and vessels. It was studied in histologic section in the three basic planes in the fetus, neonate, and adult. In the retrobulbar area, that is, posterior to the eyeball, adipose tissue occupies the space around the optic nerve and penetrates between the recti muscles, describing a four-leafed clover pattern in frontal section. The fatty tissue of the retrobulbar area also includes the peripheral ring of fat that lies between the muscles and the walls of the orbit. In the part of the peribulbar area located between the muscular insertions on the eyeball anteriorly and the emergence of the optic nerve from the sclera posteriorly, the pattern of adipose tissue is identical to the peripheral ring of fat and the fat between the muscles in the retrobulbar area. External to the muscular insertions and the anterior part of the eyeball, there is a thin ring of histologically similar fatty tissue that is continuous anteriorly with the fatty bodies of the upper and lower eyelids. Histologic examination shows that the lobules are large in that part of the retrobulbar area within the muscle cone and that they are smaller with more fibrous septa in the remaining restricted regions, such as the area between the eyeball and muscles and in the rings around the muscles and around the eyeball. In no case was a septum found separating the peripheral adipose ring from the fat located within the muscle cone.

Microvascularisation of the raphe buccalis in edentulous subjects, fetus, new-born and adult.

The aim of this study is to describe the microvascularisation of the raphe buccalis located at the inner surface of the cheek. The raphe buccalis is the zone where the maxillary and mandibulary prominences fuse in the embryo during the second month of life. This study was conducted using heads from edentulous subjects, fetuses, newborns and adults, injected with Indian ink in agar, then dissected or sectioned in the three basic planes. The vascular networks of the raphe buccalis are as followed: a deep reticular network, a superficial reticular network and a papillary network. The microvascularisation of the raphe buccalis classifies it as a continuation of the commissure of the mouth and of the mucosa of the cheek.

Anatomy and imaging of the deep fat of the face.

The aim of this study is to investigate the deep adipose structures of the face. This study is undertaken on anatomical material dissected or sectioned in the three basic planes and in histological sections. The buccal fat pad is described with its main part and its various extensions implicating several superficial and deep regions of the face. Likewise, the parapharyngeal fat pad in the prestyloid space is described. The histology of the structures is discussed, together with the non-mobilizable nature of the fat. Imaging by MRI shows the shape and relations of these fat pads with the neighboring viscera and muscles and their role as early markers in tumor invasion. Finally, their function, as an intermuscular sliding structure, is highlighted.

Is the renal space closed?

The aim of this study is to verify the aperture or the closure of the renal space. The study is undertaken on histological sections of fetuses in the horizontal and sagittal planes. On each side, the kidney and the suprarenal gland are disposed in a space that is closed on all sides. The anterior and posterior layers of the renal fascia fuse at the upper pole of the space to become continuous with the inferior fascia of the diaphragm. Likewise, they merge at the lower pole and at the lateral border of the space to become continuous with the fasciae of the parietal muscles. At the medial border of the space, the two layers merge to continue medially with the peri-aortocaval connective tissue; they penetrate the hilum and beneath it enclose the ureter.

Microvascularisation of lips in ageing edentulous subjects.

Macroscopic changes of the lips in the edentulous elderly subject are accompanied by variations in their microvascularisation. This study was undertaken on histological or clarified sections from totally edentulous subjects whose vascular system was injected with Indian ink agar. A reduction in density and size of the superficial (papillary or mucosal) and deep (reticular or submucosal) networks is observed with age. These changes are to be seen in relation to imaging and to the reduction in occlusal potential of the lips.