Anatomy of lumbar facet joint: a comprehensive review.

Lumbar facet joints (LFJs) are diarthrodial joints which provide articulation between two adjacent lumbar vertebrae. LFJs represent complex anatomic structures with multifaceted biomechanical and functional characteristics. They are theorized as structures of crucial clinical significance since their degenerative morphologic alterations are frequently related to emergence of low back pain. Despite the emerging interest in describing LFJs anatomy in recent years, precise description of LFJs innervation remains controversial. In this comprehensive review, anatomy and biomechanical importance of LFJs and associated adjacent extra-articular structures are thoroughly presented. Furthermore, LFJs innervation in respect to current literature data is punctually analysed. Knowledge of anatomy and innervation LFJs of critical importance for clinicians and spine surgeons, so that patients are properly evaluated and related therapeutic procedures are rationally performed.

Acetabular labrum of hip joint in osteoarthritis: A qualitative original study and short review of the literature.

PURPOSE: Histological architecture of normal acetabular labrum regarding free nerve endings (FNEs) and mechanoreceptors (MRs) has been satisfactorily described in the literature. However, the presence of FNEs and MRs in acetabular labrum of hip joint has been analyzed only once in patients with osteoarthritis (OA). Aim of this article is to report histological distribution pattern of FNEs and MRs in acetabular labrum of patients with severe OA, at the same time conducting a comparison with normal acetabular labrum described in the literature. METHODS: Seven patients with severe hip OA were enrolled in this study. Patient selection was assisted by the utilization of specific clinical scales delineated by the American College of Rheumatology. After successful total hip arthroplasty, tissue samples of acetabular labra of seven patients were histologically processed and stained with the gold standard chloride method, which was subsequently examined under a compound microscope. RESULTS: FNEs and MRs constituted the major histological structures. Identified MRs included Pacini corpuscles, Ruffini corpuscles, and Golgi-Mazzoni corpuscles. The presence of FNEs was predominant in the middle part of the acetabular labrum, featuring a remarkable decrease in peripheral parts. In contrast, MRs were detected basically in peripheral parts and less in the middle part. CONCLUSIONS: Differentiation of the distribution pattern of MRs and FNEs in acetabular labrum of hip joint is remarkable between normal patients and patients with severe OA. The abundance of FNEs in the middle part of the pathologic labrum is mainly responsible for the observed discrimination. A "conversion" of MRs to FNEs may occur during OA progression, modulating therefore this pattern as well as the upcoming clinical manifestations.

Morphological approach of the sternal foramen: an anatomic study and a short review of the literature.

BACKGROUND: The sternal foramen (SF) constitutes a specific anatomic defect in sternum, indicating an impaired fusion of ossificated segments, which occurs either in an anatomical part of the sternum or in sternal joints. The aim of this article is to provide baseline statistical data about the variations of the SF, to present a short review of the relevant literature and to compare results with other studies and populations. MATERIALS AND METHODS: We review relevant literature, and we present data obtai-ned from skeletal samples of known population and sex. A total of 35 well-preserved dried sterna from the prefecture of Eastern Macedonia and Thrace, Greece, were selected: 20 men and 15 women with a mean age of 55 ± 6 years old. Measurements were made with a sliding calliper and photographic documentation. RESULTS: The incidence of the SF in the 35 dried specimens was 14.2%, 4 men (20% of male sample) and 1 woman (6.6% of female sample) and 80% of sternal foramina were observed in male individuals. The SF was found in the sternum body (2 cases, 40% of foramina), in xiphoid process (2 cases, 40% of foramina) and in sternoxiphoidal junction (1 case, 20% of foramina). All of the sterna presented 1 single visible SF. Two anatomically unique cases were identified throughout these 5 sterna, both belonging in male subjects. CONCLUSIONS: The SF constitutes a relatively common variation with great radiological, clinical, and forensic significance. Presence of a SF with irregular bony margins complicates considerably radiological differential diagnosis. Awareness of this important anatomic variation is fundamental for clinicians and autopsy pathologists, in order to avoid severe fatal complications and elucidate the exact cause of death, respectively.

A comparative immunohistochemical investigation of the consequences of chorioamnionitis on the developing human fetal spleen.

INTRODUCTION: The objective of this study was to determine the effects of chorioamnionitis on the extracellular matrix (ECM) structural glycoproteins of the developing human fetal spleen, and their influence on the haematopoiesis and spleen immune system compared to controls. MATERIALS AND METHODS: After elective induced pregnancy termination due to chorioamnionitis or voluntary abortion, paraffin-embedded specimens from the spleen and respective fetal membranes of 90 fetuses were investigated by immunohistochemistry for presence of ECM structural glycoproteins, haematopoietic, and lymphoid cells. Conventional histological examination of the relative fetal membranes was performed. RESULTS: The present results showed no quantitative variations in the expression of the ECM glycoproteins and haematopoietic lineages of the fetal spleen parenchyma at the end of first trimester (in both groups). At the second and third trimesters, acute chorioamnionitis showed a decreased number of the aforementioned proteins, with an increase of granulopoiesis and CD34 progenitor/stem haematopoietic cells. The immune system of the spleen during the third trimester demonstrated a decrease of both B and T lymphocytes, in comparison with controls. CONCLUSIONS: These results suggest that toxins and cytokines generated during chorioamnionitis, seem to influence ECM structural glycoproteins synthesis and release in fetal splenic parenchyma by reducing them, and probably cause further disorders of haematopoiesis and lymphopoiesis.

Impact of chorioamnionitis on the development of human fetal lung: an immunohistochemical study.

PURPOSE: Current studies suggest that changes of chorioamnionitis are associated with the appearance of bronchial-associated lymphoid tissue (BALT), during fetal development. The aim of this study was to examine and analyse apart from the appearance of BALT, the expression of structural proteins in the lung parenchyma during gestation. MATERIALS AND METHODS: A series of 149 paraffin-embedded human fetal lung specimens at the second trimester of development were examined by immuunohistochemistry using the monoclonal antibodies CD20, CD3, Tenascin-C, Vimentin, and Fibronectin. RESULTS: The results of this study showed that (1) BALT does not develop in fetal period and (2) BALT which develops during fetal period is probably in response to antigenic stimulation where in the present cases occurs to be changes of chorioamnionitis which decreased the expression of filaments proteins in the intermediate cells of lung parenchyma in comparison with the normal ones. CONCLUSION: The expressions' pattern of intermediate filaments proteins in the lung parenchyma can be modified by the presence of chorioamnionitis in the fetal membranes.