Quantitative analysis of uterosacral ligament origin and insertion points by magnetic resonance imaging.
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OBJECTIVE: To estimate the percentage of healthy women in whom the uterosacral ligaments are identifiable on standard magnetic resonance imaging (MRI) scans and to determine origin points from the genital tract and insertion points on the pelvic sidewall. METHODS: Eighty-two asymptomatic women (mean +/- standard deviation age 53 +/- 12 years; mean parity 2.5, range 0-7) volunteered for this study. They were eligible if the most dependent vaginal wall point lay at least 1 cm above the hymenal ring remnant during a Valsalva maneuver. Axial proton density MRI of the entire pelvis was analyzed at 5-mm intervals. All results were referenced to the ischial spine. We determined the visibility of the uterosacral ligaments and located their origins from the genital tract and their insertion points on the pelvic sidewall. RESULTS: Uterosacral ligaments were visible in 61 (87%) of 70 analyzable scans. They extended over a mean craniocaudal distance of 21 +/- 8 mm (range 10-50). Three regions of origin were found: cervix alone, cervix and vagina in the same section, and vagina alone. Thirty-three percent, 63%, and 4% of 254 identified origin points were from these three areas, respectively. Of 259 uterosacral insertion points, 82% overlaid the sacrospinous ligament/coccygeus muscle complex, 7% the sacrum, and 11% the piriformis muscle, the sciatic foramen, or the ischial spine. Although uterosacral ligament morphology was similar bilaterally, its craniocaudal extent was greater on the right side. CONCLUSION: In healthy women, the uterosacral ligament origin and insertion points exhibited greater anatomic variation than their name would imply. (+info)
Homeobox protein MSX2 acts as a molecular defense mechanism for preventing ossification in ligament fibroblasts.
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Ligaments and tendons are comprised of tough yet flexible connective tissue. Little is known, however, about the precise characteristics of the cells in ligaments and tendons due to the absence of specific markers and cell lines. We recently reported a periodontal ligament cell line, PDL-L2, with suppressed Runx2/Osf2 transcriptional activity and an inability to form mineralized nodules. The present study demonstrates that the homeobox protein Msx2 is a key factor in suppressing those two functions. Msx2 colocalizes with Runx2/Osf2 and suppresses its activity cooperatively, acting with another corepressor, TLE1, as a complex to recruit histone deacetylase 1 activity. Reverse transcription-PCR and in situ hybridization demonstrated that Msx2 expression is higher in periodontal ligament and tendon cells than in osteoblasts. Stable reduction of Msx2 expression in PDL-L2 cells induces osteoblastic differentiation, thereby causing matrix mineralization. Conversely, stable, forced Msx2 expression in MC3T3-E1 cells prevented osteoblast differentiation and matrix mineralization. Msx2-induced suppression of osteoblast differentiation was repressed by bone morphogenetic protein 2. In addition, Msx2 was downregulated in a symptom- and calcification-dependent manner at the affected region in patients with ossification of the posterior longitudinal ligament. Our findings indicate that Msx2 plays a central role in preventing ligaments and tendons from mineralizing. (+info)
Hand and wrist injuries: Part I. Nonemergent evaluation.
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Diagnosis of upper extremity injuries depends on knowledge of basic anatomy and biomechanics of the hand and wrist. The wrist is composed of two rows of carpal bones. Flexor and extensor tendons cross the wrist to allow function of the hand and digits. The ulnar, median, and radial nerves provide innervation of the hand and wrist. A systematic primary and secondary examination of the hand and wrist includes assessment of active and passive range of motion of the wrist and digits, and dynamic stability testing. The most commonly fractured bone of the wrist is the scaphoid, and the most common ligamentous instability involves the scaphoid and lunate. (+info)
MAGP-2 has multiple binding regions on fibrillins and has covalent periodic association with fibrillin-containing microfibrils.
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The interactions of microfibril-associated glycoprotein (MAGP)-2 have been investigated with fibrillins and fibrillin-containing microfibrils. Solid phase binding assays were conducted with recombinant fragments covering fibrillin-1 and most of fibrillin-2. MAGP-2, and its structure relative MAGP-1, were found to bind two fragments spanning the N-terminal half of fibrillin-1 and an N-terminal fragment of fibrillin-2. Blocking experiments indicated that MAGP-2 had a binding site(s) close to the N terminus of the fibrillin-1 molecule that was distinct from that for MAGP-1 and an additional, more central binding site(s) that may be shared by the two MAGPs. Immunogold labeling of developing nuchal ligament tissue showed that MAGP-2 had regular covalent and periodic (about 56 nm) association with fibrillin-containing microfibrils of elastic fibers in this tissue. Further analysis of isolated microfibrils indicated that MAGP-2 was attached at two points along the microfibril substructure, "site 1" on the "beads" and "site 2" at the "shoulder" of the interbead region close to where the two "arms" fuse. In contrast, MAGP-1 was located only on the beads. Comparison of the MAGP-2 binding data with known fibrillin epitope maps of the microfibrils showed that site 1 correlated with the N-terminal MAGP-2 binding region, and site 2 correlated with the second, more central, MAGP-2 binding region on the fibrillin-1 molecule. Of particular note, immunolabeling at site 2 was markedly decreased, relative to that at site 1, on extended microfibrils with bead-to-bead periods over 90 nm, suggesting that site 2 may move toward the beads when the microfibril is stretched. The study points to MAGP-2 being an integral component of some populations of fibrillin-containing microfibrils. Moreover, the identification of multiple MAGP-binding sequences on fibrillins supports the concept that MAGPs may function as molecular cross-linkers, stabilizing fibrillin monomers in folded conformation within or between the microfibrils, and thus MAGPs may be implicated in the modulation of the elasticity of these structures. (+info)
Changes in gonadal steroid receptors in the cardinal ligaments of prolapsed uteri: immunohistomorphometric data.
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BACKGROUND: The precise mechanism of uterine prolapse is poorly understood. This immunohistochemical study was performed on paraffin-embedded sections of the cardinal ligaments in an attempt to evaluate the differential expression of gonadal steroid receptors in human cardinal ligaments of prolapsed uteri compared with non-prolapsed controls. METHODS: Specimens from women with pelvic organ prolapse (POP) stage III (n = 33), together with the appropriate controls (n = 25), were stained for estrogen receptor alpha (ERalpha), ERbeta, progesterone receptor (PR), androgen receptor (AR) and Ki-67. The control materials were samples of the cardinal ligaments obtained from pre- and post-menopausal women with no prolapse, who were not using hormonal therapy. RESULTS The prolapsed ligaments expressed 1.5-2.5 times more ERalpha-positive cells (statistically significant in post-menopausal women not taking HRT, P < 0.001), a 3-4 times greater percentage of AR-positive cells (P = 0.004 and P = 0.008 in pre-menopausal and post-menopausal women not taking HRT, respectively) and twice the percentage of PR-positive cells (statistically significant in the pre-menopausal group, P = 0.03) compared with the no prolapse group. Expression of ERbeta was twice as high in the ligaments of pre-menopausal women with no prolapse compared with those with prolapse (P = 0.02), and no significant difference was found in the post-menopausal groups. The use of HRT was significantly associated with low AR and high PR expression. Ki-67 expression was not detected in these specimens. CONCLUSIONS: The clearly discernible levels of expression of ERalpha, ERbeta, AR and PR in the prolapsed cardinal ligaments may suggest a relationship to the process of tissue stretch 'trauma', rather than an effect of the menopausal status, HRT use or cell proliferation. The use of HRT in post-menopausal women appears to offset some of the changes observed with the prolapse. (+info)
Musculoskeletal ultrasound--a state of the art review in rheumatology. Part 2: Clinical indications for musculoskeletal ultrasound in rheumatology.
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Rheumatologists remain divided on whether they should introduce musculoskeletal ultrasound (MSUS) into their clinical practice. A central issue in the application of MSUS in clinical rheumatology is the need for proof of clinical relevance and improved patient care. There is now accumulating evidence that MSUS improves clinical diagnosis and intervention skills. High-resolution ultrasound is superior to clinical examination in the diagnosis and localization of joint and bursal effusion and synovitis. MSUS is the imaging modality of choice for the diagnosis of tendon pathology. MSUS is seven times more sensitive than plain radiography in the detection of rheumatoid erosions, allowing earlier diagnosis of progressive rheumatoid arthritis. Ligament, muscle, peripheral nerve and cartilage pathology can also be readily demonstrated by MSUS. There is exciting evidence that MSUS may potentially be used by rheumatologists to non-invasively diagnose and monitor not just joint and muscle disease but also nerve compression syndromes, scleroderma, vasculitis and Sjogren's syndrome. Joint aspiration and injection accuracy can be improved by MSUS, with initial evidence confirming improved efficacy. As the number of rheumatologists performing MSUS increases and the technical capabilities of MSUS improve, there is likely to be a growing number of proven clinical indications for the application of MSUS in rheumatology practice. This paper reviews the evidence for the application of MSUS in rheumatology. (+info)
Correlation between inter-vertebral disc morphology and the results in patients undergoing Graf ligament stabilisation.
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BACKGROUND: Previous studies have shown Graf ligament stabilisation procedure to give mixed results in the short to medium term. The aim of this study was to correlate the pre-operative state of the disc, multifidus muscles, age of the patient, levels operated and the clinical outcome after a mean follow-up of 47 months. METHODS: Graf ligament stabilisation procedure was carried out in 38 patients between 1996 and 1999. Their post-operative status was assessed using MacNab criteria. The post-operative follow-up was by postal questionnaires and review of the clinical notes. Disc morphology and multifidus muscle wasting was graded blindly and independently. The intra- and interobserver reliability was measured with kappa score and classified using the kappa classification of Landis and Koch. Correlation was measured with the help of Spearman correlation coefficient. RESULTS: Thirty-eight patients (100%) returned the questionnaires. Mean follow-up time was 47.55 months. Fifty-nine levels were operated on. Mean age was 39.68 years. The overall re-operation rate was 15.8%. The intra- and interobserver reliability was graded as good to substantial. Twenty-two patients (57.89%) were satisfied with the procedure. There was no statistically significant correlation between disc morphology, multifidus muscle wasting, sex, age, number of levels operated, the levels operated, and the satisfaction rate. CONCLUSIONS: The indications of Graf ligament stabilisation procedure are not clear. Further work is necessary to clearly identify the indication for the procedure. (+info)
A comparison of duplex Doppler sonography of the ligamentum teres and portal vein with endoscopic demonstration of gastroesophageal varices in patients with chronic liver disease or portal hypertension, or both.
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The ability of duplex Doppler sonography of the ligamentum teres and portal vein to detect specific signs of portal hypertension was compared with the ability of endoscopy to demonstrate gastroesophageal varices in consecutive patients. Among 90 patients with parenchymal liver disease and a high probability of portal hypertension, 70 had varices, 72 had specific sonographic signs, and four had neither. Ultrasonography was comparable to endoscopy irrespective of the clinical severity of the underlying liver disease. Eleven patients had vascular occlusive diseases; nine had varices; and all had at least one sonographic sign. Duplex Doppler ultrasonography may have a clinical role in noninvasive detection of portal hypertension. Further studies correlating the findings with those of portal pressure are needed to define the place of duplex Doppler ultrasonography as a predictor of the presence of portal hypertension. (+info)