Anatomic considerations and the relationship between the piriformis muscle and the sciatic nerve

Stating background  The piriformis syndrome is one of the non-discogenics causes of sciatica. It results from the compression of the sciatic nerve (SN) by the piriformis muscle (PM) in the neutral and piriformis stretch test position. The evidence of the increase in pain in the test position requires a detailed anatomical study addressing the changes that occurred in the SN and PM anatomy during the test position. The aim of this study is to examine this relationship morphometrically. Materials and methods  A total of 20 right and left lower limbs of ten adult cadavers were examined. The SN and the PM were made visible. The location of the SN was evaluated with respect to the consistent bony landmarks, including the greater and the lesser trochanter of the femur, the ischial tuberosity, the ischial spine of the hip bone, the posterior inferior iliac spine of the hip bone and the posterior superior iliac spine of the hip bone. The study was done in both neutral and test positions (i.e., 30° adduction 60° flexion and approximately 10° medial rotation position of the hip joint). Results  The width of the greater sciatic notch was 63.09 ± 13.59 mm. The length of the lower edge of the PM was 95.49 ± 6.21 mm, and whereas the diameter of the SN where it emerged from the infrapiriforme was 17.00 ± 3.70 mm, the diameter decreased to 11.03 ± 2.52 mm at the level of the lesser trochanter of the femur. The SN intersected the PM most commonly in its medial second quarter anatomically. The vertical distance between the medial edge of the SN–PM intersection point and the ischial tuberosity was 85.62 ± 17.23 and 72.28 ± 7.56 mm (P < 0.05); the angle between the SN and the transverse plane was 66.36° ± 6.68° and 71.90 ± 8.48° (P < 0.05); and the vertical distance between the medial edge of the SN and the apex of the ischial spine of the hip bone was 17.33 ± 4.89 and 15.84 ± 4.63 mm (P > 0.05), before and after the test position, respectively. Conclusion  This study provides helpful information regarding the course and the location of the SN. The presented morphometric data also revealed that after stretch test position, the infrapiriforme foramen becomes narrower; the SN becomes closer to the ischial spine of the hip bone, and the angle between the SN and the transverse plane increases. This study confirmed that the SN is prone to be trapped in the test position, and diagnosis of this situation requires dynamic MR and MR neurography study.     

Identification of DIO2 as a new susceptibility locus for symptomatic osteoarthritis

Osteoarthritis [MIM 165720] is a common late-onset articular joint disease for which no pharmaceutical intervention is available to attenuate the cartilage degeneration. To identify a new osteoarthritis susceptibility locus, a genome-wide linkage scan and combined linkage association analysis were applied to 179 affected siblings and four trios with generalized osteoarthritis (The GARP study). We tested, for confirmation by association, 1478 subjects who required joint replacement and 734 controls in a UK population. Additional replication was tested in 1582 population-based females from the Rotterdam study that contained 94 cases with defined hip osteoarthritis and in 267 Japanese females with symptomatic hip osteoarthritis and 465 controls. Suggested evidence for linkage in the GARP study was observed on chromosome 14q32.11 (log of odds = 3.03, P = 1.9 x 10(-4)). Genotyping tagging single-nucleotide polymorphisms covering three important candidate genes revealed a common coding variant (rs225014; Thr92Ala) in the iodothyronine-deiodinase enzyme type 2 (D2) gene (DIO2 [MIM 601413]) which significantly explained the linkage signal (P = 0.006). Confirmation and replication by association in the additional osteoarthritis studies indicated a common DIO2 haplotype, exclusively containing the minor allele of rs225014 and common allele of rs12885300, with a combined recessive odds ratio of 1.79, 95% confidence interval (CI) 1.37-2.34 with P = 2.02 x 10(-5) in female cases with advanced/symptomatic hip osteoarthritis. The gene product of this DIO2 converts intracellular pro-hormone-3,3',5,5'-tetraiodothyronine (T4) into the active thyroid hormone 3,3',5-triiodothyronine (T3) thereby regulating intracellular levels of active T3 in target tissues such as the growth plate. Our results indicate a new susceptibility gene (DIO2) conferring risk to osteoarthritis.     

Lumbar vertebral hemangioma with extradural extension, causing neurogenic claudication: a case report

The authors present a rare case of lumbar vertebral hemangioma extending to the epidural space with a bisected appearance and impinging on thecal sac. This 52-year-old lady presented with one year history of low back pain and bilateral leg radiation. Plain radiography showed vertical linear streaks at L2 vertebral body and axial computed tomography (CT) scan revealed small "polka dot" appearance within the vertebral body. Magnetic resonance imaging (MRI) showed low signal intensity on T1-weighted images in L2 vertebral body which was not characteristic for hemangioma. The patient underwent an L2 laminectomy, spinal canal decompression and posterior spinal instrumentation. This study indicates that lumbar vertebral hemangioma can extend to the epidural space and cause neurologic symptoms. Magnetic resonance imaging may not show diagnostic features, especially in active lesions and plain radiography and CT scan may be helpful.     

NOD2 exonic variations in Iranian Crohn's disease patients

Purpose

The NOD2 gene is known to have a strong association with Crohn??s disease, but different trends were reported in occurrence of NOD2 variants in distinct ethnicities. The aim of this study was to assess all exonic sequences of the NOD2 gene in Iranian Crohn's disease patients and healthy controls to identify any existing variation and evaluate their association with Crohn's disease.

Methods

A total of 90 non-related Crohn's disease patients and 120 sex- and age-matched healthy controls of Iranian origin were enrolled in this study. The participants were referred to a tertiary center in a 2-year period (2006?C2008). The exonic regions of the NOD2 gene were amplified by polymerase chain reaction and evaluated by direct sequencing.

Results

A total of 21 sequence variations were identified among all exonic regions of the NOD2 gene, of which eight had an allele frequency of more than 5%. Eight new mutations (one in exon 2 and seven in exon 4) were observed. The three main variants (R702W, G908R, and 1007fs) showed allele frequencies of 13.3%, 2.2%, and 1.7%, respectively. Three new variations (P371T, A794P, and Q908H) and R702W mutation were significantly more frequent in Crohn's disease patients compared to controls.

Conclusions

Eight novel mutations were identified in the NOD2 exons, but the pathophysiological importance of these variants remains unclear. Iranian patients with their different genetic reservoirs may demonstrate some novel characteristics for disease susceptibility.     

Evaluation of corneal biomechanical properties in mustard gas keratopathy

Background

Degenerative biomechanical factors and immunologic processes with effect on collagen and corneal reparative process are known as the main cause of ocular surface dysfunction in mustard gas keratopathy (MGK) and may cause changes in the corneal biomechanical values. Therefore, we evaluate corneal biomechanical properties of these patients.

Prevalence of Chronic Diseases and Occupational Injuries and their Influence on the Health-Related Quality of Life Among Farmers Working in Small-Farm Enterprises

Objectives: This study aimed to determine the prevalence of chronic diseases and occupational accidents and injuries, and to examine their association with the quality of life among a sample of Iranian farmers.

Methods: A cross-sectional study was conducted among 736 male farmers. Data on the prevalence of chronic diseases and occupational accidents and injuries was collected using an author-developed questionnaire, and the SF-36 questionnaire was used to obtain information on quality of life.

Results: The prevalence of chronic diseases was 96.1%. Musculoskeletal diseases (MSDs), eye diseases and neurology diseases were the most prevalent diseases. Almost half of the farmers (42.7%) had experienced an occupational accident during the last 12 months and cuts and fractures accounted for the most frequent injuries. Sick leave was reported by 28.2% of the farmers and from those with history of accidents, 21.4% were hospitalized. A significant association was found between age and education level with quality of life. Most of the chronic diseases showed a significant and inverse association with quality of life, however, the strongest association was found for MSDs and mental disorders. Furthermore, the most important injury associated with quality of life was cuts and fractures.

Conclusions: Based on the results, MSDs, mental disorders, and cut and fractures were the main determinants of the farmers’ quality of life. Hence, a better quality of life among farmers is especially dependent on eliminating ergonomics risk factors leading to developing musculoskeletal disorders, improving psychosocial work climate, and promoting occupational and personal safety culture.     

Microvascular Coronary Dysfunction—an Overview

Purpose of Review

We will review the available data on the epidemiology, pathophysiology, diagnosis, and management of microvascular coronary dysfunction (MCD).

Recent Findings

The study of MCD was pioneered by the Women’s Ischemia Syndrome Evaluation (WISE) cohort. New techniques in the diagnosis of this condition, using invasive and noninvasive means, are helping to increase awareness of this condition as well as ways in which to treat it.

Summary

Microvascular coronary disease without epicardial involvement has become an increasingly recognized cause of cardiac chest pain, particularly in women. Dysfunction of the microvasculature related to endothelium-dependent and endothelial-independent factors likely results in symptoms and/or evidence of ischemia. Although there is a growing body of research, there is still much about MCD that we do not understand.

     

Neural Differentiation of Wisdom Tooth Follicle Stem Cells on a Nano-Hydrogel Scaffold Containing Salvia Chloroleucat to Treat Nerve injury in the Cancer of Nervous System

The human third molar’s follicle is one of the sources of stem cells with high differentiation capacities which can be used in nervous system cancer treatment particularly in nerve damge. The purpose of this research was to identify the effects of the aqueous extract of Salvia chloroleuca on the differentiation of the human dental follicle-derived mesenchymal stem cells to neural cells for treti. In this experimental study, the method of culture of digested tissue fragments was used to isolate stem cells from three samples of the extracted wisdom teeth follicles. The nano-hyaluronic acid scaffold has been synthesized by the sol-gel method as a porous composite and the S. chloroleuca extract has been loaded into it. The scaffold was analyzed in terms of mechanical properties, drug release and toxicity. Afterwards, the cells were seeded onto the scaffold using the immersion method. After 21 days, cell differentiation was investigated by morphological confirmation methods and confirming the expression of β-tubulin and MAP2 genes at mRNA and protein levels. Morphological assessment revealed neural differentiation in the cells of the groups of nano-hyaluronic acid scaffold with S. chloroleuca extract and nano-hyaluronic acid scaffold with S. chloroleuca extract + 10% retinoic acid. Furthermore, the expression of MAP2 and β-tubulin in these groups was confirmed by RT-PCR, real time PCR and western blot assays. The results of this research showed that the follicle of the third molar contains stem cells with a high capacity for differentiation. Moreover, the extract of S. chloroleuca, could lead to induction of neural differentiation in stem cells.