Mechanisms of proximal hamstring rupture in a non-athlete healthy middle-aged female.

PURPOSE: To present an explicatory pathophysiological model for the rare clinical case of a total proximal hamstring rupture for the first time in the literature. METHODS: A non-athletic healthy female (49 years) experienced a complete rupture of the right conjoint tendon of the biceps femoris (long head) and semitendinosus muscle while slipping down a lawn-covered slope (eccentric hip flexion and knee extension during stance phase of gait after heel-strike). A hamstring rupture was diagnosed by clinical examination and confirmed by magnet resonance imaging (MRI). Surgical reattachment of the conjoint tendon to the ischial tuberosity was performed. One year after surgery, she experienced no pain or functional impairment. RESULTS: Histological analysis and immune-histochemical staining (vascular endothelial growth factor - receptor 2) of a biopsy taken intra-operatively revealed signs of fibroblast proliferation and vasculoneogenesis with absence of inflammatory changes indicating that repairing mechanisms and tissue remodeling had been taking place. CONCLUSION: This case report provides evidence for the hypothesis that micro-injuries induce repairing mechanisms and thus tissue remodeling which leads to consecutive tissue weakening and mechanical failure during a non-adequate trauma. Micro-injuries can occur during leisure activities and remain clinically invisible until rupture.

In-vivo topography of structural alterations of the anterior cingulate in patients with schizophrenia: new findings and comparison with the literature.

The anterior cingulate cortex (ACC) is part of the rostral limbic system and is involved in cognitive and affective processes that have been reported to be disturbed in schizophrenia. Despite the evidence for ACC abnormalities in schizophrenia indicated by functional imaging studies, structural magnetic resonance imaging (MRI) studies of this region of interest (ROI) have been relatively few and the results inconsistent. The aim of the present study was to examine the hypothesis that different subregions of the ACC are differentially affected by the disease process of schizophrenia, a circumstance that might contribute to contradictory results of earlier structural ACC studies. We investigated ACC volumes in 50 male and right-handed patients with schizophrenia according to ICD-10 and DSM-IV. The patients were individually matched for age, sex, handedness and education with 50 control subjects. ACC was subdivided into four parts: precallosal, subgenual, precommissural and postcommissural regions. Measurements were performed with a 1.5 T magnetom vision apparatus. Regions of interest were defined on consecutive coronal MRI-slices. The software program BRAINS was used for volumetry and segmentation into gray and white matter. We detected that ACC gray matter volume of the right precallosal region and right total ACC was significantly reduced in schizophrenic patients compared with control subjects. In addition, left ACC gray matter was selectively reduced in the subgenual region. These results confirmed our hypothesis that different ACC regions are differentially affected by structural alterations in schizophrenia, a circumstance that might explain in part the discrepant findings of former structural imaging studies of the ACC.