The current model of compact bone is that of a system of Haversian (longitudinal) canals connected by Volkmann's (transverse) canals. Models based on either histology or microcomputed tomography do not accurately represent the morphologic detail and microstructure of this system, especially that of the canal networks and their spatial relationships. The aim of the present study was to demonstrate the morphologic pattern and network of the Haversian system and to compare endosteal and periosteal sides in rats using three-dimensional (3D) reconstruction. Ten Sprague-Dawley rats aged 8-10 weeks were used. The femurs were harvested from each rat and fixed, decalcified with 10% EDTA-2Na, serially sectioned at a thickness of 5 µm, and then stained with hematoxylin and eosin. The serial sections were reconstructed three-dimensionally using Reconstruct software. The Haversian canals in the endosteal region were found to be large, highly interconnected, irregular, and close to neighboring canals. In contrast, the canals in the periosteal region were straight and small. This combined application of 3D reconstruction and histology examinations to the Haversian system has confirmed its microstructure, showing a branched network pattern on the endosteal side but not on the periosteal side.

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The aim of this study was to define the location of the accessory infraorbital foramen (AIOF) with reference to accessible external landmarks in order to facilitate orbital and oculoplastic surgical procedures in the maxillofacial region. Forty-four hemifaces from 25 cadavers were dissected. The lateral canthus, subnasal point, and lacrimal caruncle were used as anatomic reference points. The AIOF was observed in 8 of the 44 hemifaces (18.2%) and was situated at a mean distance of 7.2 mm superomedial to the IOF. The horizontal distance from the lacrimal caruncle to the AIOF was 0.3 mm. In all cases the AIOF was situated at a point that was no more than 8 mm from the intersection point of a vertical line passing through the lacrimal caruncle and an oblique line joining the lateral canthus and the subnasal point. Surgeons anesthetizing or performing surgical procedures in the maxillofacial region should be aware of the frequency of the AIOF (18.2%) and its location (on the superomedial side of the IOF). We propose that injecting at the intersection point of a vertical line passing through the lacrimal caruncle and an oblique line joining the lateral canthus and the subnasal point would successfully block the accessory branch of the infraorbital nerve. Likewise, surgeons operating in this region should be aware of the location of the AIOF in order to avoid inadvertent iatrogenic injury to a duplicated infraorbital nerve.

A more detailed description of the anterior wall of the ulnar tunnel than was previously available is presented herein, and topographic and metric data regarding each structure of the tunnel are reported.

The morphology of the AGA scalp has been characterized. The terminal-to-vellus hair ratio in the occipital (normal) region was different from that in the frontal (alopecic) region. Moreover, sebaceous glands were larger in the frontal alopecic region than in the occipital region. These larger glands may be associated with other dermatological pathologies, such as seborrhoeic dermatitis.