Muscle Sheath Research Articles

Identification and Characterization of a Conformational Heparin-binding Site Involving Two Fibronectin Type III Modules of Bovine Tenascin-X

Tenascin-X is known as a heparin-binding molecule, but the localization of the heparin-binding site has not been investigated until now. We show here that, unlike tenascin-C, the recombinant fibrinogen-like domain of tenascin-X is not involved in heparin binding. On the other hand, the two contiguous fibronectin type III repeats b10 and b11 have a predicted positive charge at physiological pH, hence a set of recombinant proteins comprising these domains was tested for interaction with heparin. Using solid phase assays and affinity chromatography, we found that interaction with heparin was conformational and involved both domains 10 and 11. Construction of a three-dimensional model of domains 10 and 11 led us to predict exposed residues that were then submitted to site-directed mutagenesis. In this way, we identified the basic residues within each domain that are crucial for this interaction. Blocking experiments using antibodies against domain 10 were performed to test the efficiency of this site within intact tenascin-X. Binding was significantly reduced, arguing for the activity of a heparin-binding site involving domains 10 and 11 in the whole molecule. Finally, the biological significance of this site was tested by cell adhesion studies. Heparan sulfate cell surface receptors are able to interact with proteins bearing domains 10 and 11, suggesting that tenascin-X may activate different signals to regulate cell behavior.

MRI abnormalities of foot and ankle in asymptomatic, physically active individuals.

To assess MRI changes in the ankle and foot after physical exercise. Nineteen non-professional marathon runners and 19 age- and sex-matched controls volunteered for the study. All had ankle and foot MR images (1.5 T) taken in three perpendicular planes (STIR, T2F and T1FS sequences) within 3 h of running a full-length marathon (42.125 km). Three radiologists independently analysed the groups on a masked basis using a predefined form. Severe bone marrow oedema was seen in one and slight bone marrow oedema in three marathon runners. Slight bone marrow oedema was found in three control subjects. Signal alteration within the soleus muscle, consistent with a grade 1 strain, was found in one marathon runner. Small punctate hyperintensities within the Achilles tendon were seen in 26% of the marathon runners and in 63% of controls (P = 0.016). An increased amount of fluid in the retrocalcaneal bursa was found in one control and in none of the marathon runners. Small amounts of fluid in the retrocalcaneal bursa were seen in 68% of marathon runners and in 53% of controls. Grade 1 or 2 peritendinous joint fluid was found around 22% of tendons, among both marathon runners and controls, most often involving the tendon sheath of the flexor hallucis longus muscle. An increased amount of joint fluid was noted in 34% of the joints of the marathon runners, and in 18% of the controls. MRI shows several abnormalities in the ankle and foot both after marathon races and in asymptomatic physically active individuals without any preceding extraordinary strain. Recreational sports may lead to a number of positive MRI findings without correlation with clinical findings.

Ultrasonography for the Diagnosis of Diseases of the Tendon and Tendon Sheath of the Biceps Brachii Muscle

To describe the ultrasonographic appearance of the normal and diseased biceps brachii tendon and its tendon sheath in dogs. A prospective clinical study. One hundred twenty client-owned dogs. In the first part of the study, the ultrasonographic appearance of the normal biceps brachii muscle and the surrounding soft tissue was determined in 27 healthy dogs. Standard views were described and established. In the second part, 120 dogs with suspected pathology of the biceps brachii muscle were examined ultrasonographically. Fifty-five of these dogs had no sonographic changes, and 65 dogs had sonographically detectable pathologic changes of the tendon or the tendon sheath or both. The mean age of the affected dogs was 3.7 years. The ratio of males to females was 1.95:1. Sedation or anesthesia of the dogs was required because of the extreme movements of the leg necessary for the examination. To achieve a perpendicular view of the tendon and the tendon sheath, the area of the shoulder joint was rotated outward and abducted as far as possible. Examination of the muscle-tendon apparatus of the biceps brachii muscle was divided into 4 main sections. Linear transducers (7.5-10 MHz) allowed the soft tissue structures to be easily visualized with ultrasonography. Pathologic changes of the tendon and tendon sheath were visualized sonographically by using high-frequency linear probes. Partial or complete tendon rupture, medial luxation of the tendon, corpora libera in the tendon sheath, and tenosynovitis were clearly shown. High-frequency ultrasonography using linear transducers allows the examiner to accurately define the pathologic changes in the region of the biceps brachii tendon in dogs. The use of sonography for diagnosis of disease processes of the tendon and tendon sheath of the biceps brachii muscle complements clinical and radiographic examination findings.

Senile ocular amyloidosis in SAM and BALB/c strains of mice

We investigated whether amyloid deposition can affect retinal atrophy in old SAMR1, SAMP1 and BALB/c mice. Immunohistochemistry revealed that old SAMP1 mice showed the deposition of the murine senile amyloid protein fibril, AApoA-II in the subconjunctival tissue, the vessel walls near the chamber angle, and the sheaths of the external ocular muscles and the conjunctival glands, but was never observed in the retina or the choroid. Although the old SAMR1 mice also showed a remarkable loss of retinal photoreceptor and ganglion cells, they never showed any amyloid deposition. The BALB/c strain did not showed any amyloid deposition either. Our data suggest that atrophy of the retina is not related to senile systemic amyloidosis in mice.

Druckentlastung im Aneurysmasack nach endovaskulärer Therapie von Aortenaneurysmen*

Stent grafting of aortic aneurysms should result in relief of pressure within the excluded aneurysmal sac, however confirming data are not available. This study evaluates the intra-extraluminal pressure translation and translation of maximum pressure increase (dp/dtmax) into the excluded aneurysmal sac after endovascular treatment of experimental aortic aneurysms. Experimental autologous aneurysms were created surgically using a patch from the sheath of the rectus abdominis muscle in 12 mongrel dogs. After 12 weeks reconvalescence, endovascular treatment was performed viafemoral access using dacron-covered nitinol stents. Spiral CT and angiography were performed at one week and six weeks follow-up and 6 animals each. Laparotomy was performed for hemodynamic measurements. A manometer-tipped catheter was introduced into the excluded aneurysmal sac. A second manometer-tipped catheter was placed intraluminally within the stent graft. Pressure curves and their first derivative dp/dt were simultaneously recorded to calculate the intra-extraluminal transmembraneous pressure transmission. At one week follow-up systolic blood pressure and mean blood pressure were significantly reduced by factors of 0.60 +/- 0.17 (p < 0.01) and 0.78 +/- 0.3 (p < 0.05), respectively in the excluded aneurysm sac. The maximal pressure increase, dp/dt max, was considerably reduced by a factor of 0.06 +/- 0.05 (p < 0.01). However, the diastolic blood pressure was not significantly changed. There were no hemodynamic differences between one and six weeks follow-up. In experimental aortic aneurysms, endovascular treatment with stent grafts significantly reduces the systolic peak pressure and dp/dt max in the excluded aneurysmal sac, and thereby significantly reduces the wall stress in the diseased aneurysm wall. Despite complete exclusion of the aneurysm, a considerable pressure load remains in the excluded aneurysmal sac.

Polypropylene mesh substitute for the fascial defect after using for the dural repair--technical note.

Use of the anterior sheath of the rectus abdominis muscle (anterior sheath) as a dural substitute and patching of the large defect of the anterior sheath with polypropylene mesh are described. Five patients were treated using the anterior sheath and the mesh. No postoperative complications such as cerebrospinal fluid leakage, infection, or abdominal wall hernia occurred. The mesh is useful as a patch for the sheath defect.

Left ventricle assist systems: a possible alternative to heart transplantation for heart failure patients? Patient selection, techniques and benefit

Left ventricle assist systems: a possible alternative to heart transplantation for heart failure patients? Patient selection, techniques and benefit

A CASE OF SPIGELIAN HERNIA PENETRATING THE EXTERNAL OBLIQUE APONEUROSIS

A 65-year-old man visited our hospital complaining of a 4×4cm soft and round mass in the right lower quadrant of the abdomen. Abdominal CT and MRI examinations disclosed an abdominal wall tumor originating from the abdominal wall muscle. In Jauary 1999, the mass became slightly enlarged, but disappeared with the patient in the supine position. A second abdominal CT examination revealed a Spigelian hernia that passed through the Spigelian fascia from the abdominal cavity. Operative findings confirmed a Spigelian hernia. The hernia sac with preperitoneal fat had penetrated the external oblique aponeurosis through the Spigelian fascia. The transverse oblique and internal oblique aponeurosis were sutured to the lateral side and anterior sheath of the rectus abdominis muscle in layers. Posterior repair of the spermatic cord using Marlex mesh was performed. His postoperative course was uneventful and he is now symptom free.

Hair cycle-dependent production of ACTH in mouse skin

We investigated the functional determinants of the cutaneous expression of elements of the hypothalamic–pituitary–adrenal axis. In the present work, the presence of adrenocorticotropin (ACTH) peptide in skin of C57/BL6 mouse was demonstrated by reversed-phase HPLC analysis combined with specific radioimmunoassay. ACTH concentration that was low in telogen, increased during anagen in two steps: a rapid phase in anagen I, and a slower rise that reached its peak in anagen VI. Immunofluorescence localized the ACTH antigen to the basal layer of epidermis, outer root sheath of hair follicle and subcutaneous muscle of anagen VI skin. At physiological plasma concentration (10 −9 M), ACTH selectively stimulated DNA synthesis in dermis, while pharmacological doses (10 −7–10 −6 M) inhibited DNA synthesis in both dermis and epidermis. In conclusion, we suggest that local production of ACTH may represent a regulatory element in the control of skin functions including hair growth.

Medial canthus single-injection episcleral (sub-tenon anesthesia): computed tomography imaging.

Single-injection medial canthus periocular anesthesia is a promising regional anesthesia technique for ophthalmic surgery. The purpose of this computed tomography (CT) study was to confirm that this technique is an episcleral injection and to explain why it provides a good akinesia of the globe. Four fresh nonpreserved cadavers (eight eyes) were injected with fractioned various volumes of a contrast media using a previously described technique. For each injection and each eye, CT scans were performed in three planes of the space, and the site and spread of the injection was observed. We confirm that single-injection medial canthus periocular anesthesia is, in fact, an episcleral anesthesia, which explains the good sensory block of the globe. When larger volumes are injected, the contrast media spreads to the lids and extraocular muscle sheaths. We believe that this may explain why this technique provides good sensory and motor block of the globe and eyelids. This technique is a promising alternative to both retro- and peribulbar anesthesia. We describe medial canthus single-injection periocular anesthesia by a computed tomography injection study in eight human cadaver eyes. It was confirmed to be an episcleral injection. Akinesia of the eyeball is provided by spreading of the local anesthetic solution from the episcleral space to the rectus muscle sheaths.

In Uteroand Lactational Exposure of the Male Rat to 2,3,7,8-Tetrachlorodibenzo-p-dioxin Impairs Prostate Development: 2. Effects on Growth and Cytodifferentiation

In the male Holtzman rat,in uteroand lactational 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure decreases prostate weight without inhibiting testicular androgen production or decreasing circulating androgen concentrations. Therefore, the present study sought to characterize effects of TCDD exposure on prostate development, from very early outgrowth from the urogenital sinus (Gestation Day [GD] 20) until rapid growth and differentiation are essentially complete (Postnatal Day [PND] 32). Pregnant Holtzman rats were administered a single dose of TCDD (1.0 μg/kg po) or vehicle on GD 15 and offspring were exposed via placental transfer (GD 20 euthanasia) or placental and subsequent lactational transfer until euthanasia (if before PND 21) or weaning. Results show that the prostatic epithelial budding process was impaired byin uteroTCDD exposure, as evidenced by significant decreases in the number of buds emerging from dorsal, lateral, and ventral aspects of the GD 20 urogenital sinus. Ventral prostate cell proliferation index was significantly decreased on PND 1 but was similar to or higher than control at later times, whereas apoptosis was an extremely rare event in ventral prostates from both control and TCDD-exposed animals. Delays were noted in the differentiation of pericordal smooth muscle cells and luminal epithelial cells. In addition, ventral prostates from approximately 40% of TCDD-exposed animals examined on PNDs 21 and 32 exhibited alterations in the histological arrangement of cell types that could not be explained by a developmental delay. Compared to controls, these ventral prostates exhibited a disorganized, hyperplastic epithelium containing fewer luminal epithelial cells and an increased density or continuous layer of basal epithelial cells, as well as thicker periductal smooth muscle sheaths. In addition, in ventral prostates from TCDD-exposed animals, the intensity of androgen receptor staining was relatively low in the central and distal epithelium, and the number of androgen receptor-positive cells was relatively high in the periductal stroma. These data suggest thatin uteroand lactational TCDD exposure interferes with prostate development by decreasing very early epithelial growth, delaying cytodifferentiation, and, in the most severely affected animals, producing alterations in epithelial and stromal cell histological arrangement and the spatial distribution of androgen receptor expression that may be of permanent consequence.

Mediastinal drainage through the umbilicus to avoid a conspicuous abdominal scar

Sternal reconstruction of chest deformities can lead to conspicuous scar formation at the site of the mediastinal drainage tube. This report presents our experience over the past two years using an improved drainage technique to reduce operative scars. This involves passing a drainage tube through the umbilicus after passing it through the anterior sheath of the rectus abdominis muscle. Good cosmetic results were achieved with no perioperative morbidity. This can also be used in thoracic surgery and can improve the aesthetic results, especially in women and children.

Three Helpful Techniques for Facilitating Abdominal Procedures, in Particular for Surgery in the Obese

Three helpful techniques for facilitating abdominal procedures, in particular in the obese, are presented. Midline abdominal exposure is aided by the manual separation of the subcutaneous fat and Scarpa’s fascia by a lateral tearing motion simultaneously performed from opposite sides of the table. Exposure of the upper abdomen is best achieved by utilization of a fixed-support retractor system placed with the patient in the Trendelenburg position, followed by positioning the patient in the reverse Trendelenburg position for the conduct of the operation. Ventral hernia repair is promoted when the three mobile layers of anterior rectus sheath, rectus muscle, and posterior rectus sheath are approximated with a continuous suture to create a neo-linea alba.

The sheath of the rectus abdominis muscle: an anatomical and biomechanical study

The anterior layer of the sheath of the rectus muscles is often used in the repair of incisional hernias through the linea alba. This practice has led us to undertake an anatomical and biomechanical study of its structure. Thirty fresh cadavers were divided into three groups of ten. All were dissected and biomechanical tests were carried out on the latter two groups: in Group 2 a dynamometer was used to measure the resistance to linear traction and to deformation. In Group 3 a bursting strength tester was used in order to determine the resistance to pressure. Morphological studies included measurements of the mean dimensions of the sheath, and of its composition at different levels. The biomechanical results show that the anterior sheath is more resistan to traction below the arcuate line than above it, whereas the resistance to pressure shows an opposite pattern. The resistance to traction of the posterior sheath is similar in its aponeurotic portion both above and below the umbilicus, the resistance to pressure being slightly less in the region of the arcuate line. The figures for deformation are essentially the same at all levels. The implications of these results for the repair of abdominal wall defects are discussed.

Structural Properties of the Intrinsic Muscles of the Malpighian Tubules of the Female Stable Fly, Stomoxys calcitrans L.

The four Malpighian tubules of the female stable fly, Stomoxys calcitrans L., were divided into an anterior dorsal and a posterior ventral pair. A marked structural divergence existed between the distal terminations of these two pairs. This divergence consisted primarily in the number and size of crystalline granules present in the respective distal regions. The terminal diameter of the dorsal tubules was at least twice that of the ventral tubules. Intrinsic muscles were found only in that short proximal section (ureter) of each pair of tubules that emptied into the midgut. Other regions of the tubules showed no evidence of a muscle sheath. The small intrinsic muscles (0.25 to 0.6 μm diam) of the ureter were visible under Nomarski optics at high magnification (600X). The muscle fibers were embedded in the basal regions of the large epithelial cells that line the lumen of the ureter. Occasionally, these muscles were arranged in a multilayered lattice. Myofibrils were separated into sarcomeres of irregular alignment with classical A (0.8 μm in length) and I bands. The Z disk consisted of discontinuous rows of dense bodies, and in partially contracted muscle some myofilaments of the A band passed between the dense bodies of the Z bands. T-system tubules and the sarcoplasmic reticulum were sparse to non-existent.

Psoas abscess communicating to an implanted hip due to delayed hematogenous tuberculosis arthritis

The authors report a rare case of an 75-year-old female patient who had had a Mueller cemented total hip arthroplasty for osteoarthritis. Eight years after implantation of the THA the patient developed a hematogenous TB arthritis in the already implanted hip. During the revision operation the infected hip was found to communicate with the ipsilateral psoas muscle sheath through a fistula which was induced by one of the screws used for stabilization of the socket. The evacuation of the abscess from the psoas sheath and the affected hip joint in combination with anti-TB medication was followed by an uneventful course, up to 48 months postoperatively.

Inguinal hernia repair with flap of the anterior sheath of the rectus muscle: Preliminary study

We have developed an alternative operative technique for the conventional repair of groin hernias using a prosthetic mesh. In our study of 75 patients with uncomplicated inguinal hernia, we used a triangular flap of the anterior sheath of rectus muscle to repair the hernia. The patients were monitored during a 5-year period. A triangular flap was designed on the anterior sheath of rectus muscle. The flap was folded and sutured to the inguinal ligament with noncontinuous and nonabsorbable suture 00; the floor of the inguinal canal and the internal ring were reinforced with low tension sutures. The postoperative progress of the patients was satisfactory. We did not observe any severe complications, and 5 years after the procedure no patient was noted to have a recurrence. The triangular flap of the anterior sheath of the rectus muscle is useful in reinforcing the inguinal canal floor with low tension sutures. Because the flap is in the same position as the prosthetic mesh in conventional inguinal hernia repair, we hope that the use of the flap will achieve the same results as the prosthetic mesh.

Functional anatomy of the levator palpebrae superioris muscle and its connective tissue system.

The connective tissue system of the levator palpebrae superioris muscle (LPS) consists of the septa surrounding its muscle sheath, the superior transverse ligament (STL) commonly referred to as 'Whitnall's ligament' and the common sheath which is the fascia between the LPS and the superior rectus muscle (SRM). The anterior band-like component of the common sheath is called transverse superior fascial expansion (TSFE) of the SRM and LPS. It mainly extends from the connective tissue of the trochlea to the fascia of the lacrimal gland. A detailed description of the relation between the LPS and its connective tissue is presented. Furthermore, the course of the LPS in the orbit is described. The study was conducted to provide a morphological basis for biomechanical and clinical considerations regarding ptosis surgery. Postmortem dissections were performed in 16 orbits from eight cadavers. The microscopical anatomy was demonstrated in six formalin preserved orbits from six cadavers which had been sectioned in the frontal and sagittal plane and stained with haematoxylin and azophloxin. Surface coil magnetic resonance imaging in the sagittal and coronal plane was performed in five orbits from five normal volunteers using a T1 weighted spin echo sequence. The STL and the TSFE surround the LPS to form a fascial sleeve around the muscle which has attachments to the medial and lateral orbital wall. The TSFE, which is thicker than the STL, blends with Tenon's capsule. The STL and the fascial sheath of the LPS muscle are suspended from the orbital roof by a framework of radial connective tissue septa. MR images show that the TSFE is located between the anterior third of the superior rectus muscle and the segment of the LPS muscle where it changes its course from upwards to downwards. In this area, the LPS reaches its highest point in the orbit (culmination point). The culmination point is located a few millimetres posterior to the equator and superior to the globe. Whitnall's ligament can be considered to consist of two distinct parts--the TSFE inferior to the LPS and the STL superior to the LPS. Since the medial and lateral main attachments of Whitnall's ligament are situated inferior to the level of the culmination point of the LPS, the ligament itself is unlikely to suspend the levator muscle. However, a suspension of the LPS may be achieved by the radial connective tissue septa of the superior orbit. The TSFE in connection with the globe may have an additional supporting function. The elasticity of Whitnall's ligament and its connections with highly elastic structures including Tenon's capsule, may provide the morphological substrate for the previously proposed passive (that is, without orbicularis action) lowering of the lid during downward saccades.

Abdominoplasty with two fusiform plications.

Two-fusiform plications are recommended for contouring the abdomen to produce a slimmer waistline in abdominoplasty, rather than the classical median xiphoid-pubic fusiform plication. This procedure was accomplished in 11 patients. After the dermoadipose flap was undermined, two fusiform shapes were marked at the transition of the sheaths of the rectus abdominis muscles with the external obliques. The slimmer waistline produced intraoperatively was maintained during the late postoperative period (mean 20 months), without loss of the natural contour between the rectus muscles. Maintenance of the natural contours of the abdominal muscles is of fundamental importance to reduce the embarrassment of a postabdominoplasty flat abdomen.

PRESUMPTIVE TENOSYNOVIAL OSTEOCHONDROMATOSIS IN A HORSE

A 5 year old Arabian mare was evaluated for a non‐painful swelling located dorsal to the right carpus which had been present for 2 years. Radiographically, multiple mineralized bodies were identified dorsal to the distal radius and carpus in the region of the tendon sheath of the extensor carpi radialis muscle. The radiographic appearance of the carpal bones was within normal limits. On ultrasound examination, multiple hyperechoic foci with posterior shadowing were seen adjacent to the extensor carpi radialis tendon. There was minimal distension of the tendon sheath and no abnormalities within the substance of the extensor carpi tendon were identified. Considering the radiographic and sonographic findings, a presumptive diagnosis of tenosynovial osteochondromatosis was made. Histological confirmation of this diagnosis was not obtained as the owner declined further diagnostic evaluation.