Why adductor magnus muscle is large: the function based on muscle morphology in cadavers.

The aim of this study was to examine anatomical properties of the adductor magnus through a detailed classification, and to hypothesize its function and size to gather enough information about morphology. Ten cadaveric specimens of the adductor magnus were used. The muscle was separated into four portios (AM1-AM4) based on the courses of the corresponding perforating arteries, and its volume, muscle length, muscle fiber length and physiological cross-sectional area were assessed. The architectural characteristics of these four portions of the adductor magnus were then classified with the aid of principal component analysis. The results led us into demarcating the most proximal part of the adductor magnus (AM1) from the remaining parts (AM2, AM3, and AM4). Classification of the adductor magnus in terms of architectural characteristics differed from the more traditional anatomical distinction. The AM2, AM3, and AM4, having longer muscle fiber lengths than the AM1, appear to be designed as displacers for moving the thigh through a large range of motion. The AM1 appears instead to be oriented principally toward stabilizing the hip joint. The large mass of the adductor magnus should thus be regarded as a complex of functionally differentiable muscle portions.

Two cases of peroneus brevis tendon tear.

A longitudinal tear of the peroneal tendon is thought to be the result of repetitive peroneal subluxation. However, this report documents two cases of longitudinal split of the peroneus brevis tendon that had no peroneal tendon subluxation. Primary suture was performed. Subluxation of the peroneal tendons was not identified surgically in either case.

Japanese experience of telemedicine in oncology.

We started telemedicine projects from 1990 with a telepathology system within Tsukiji Campus of National Cancer Center. In 1994, we connected Tsukiji Campus and Kashiwa Campus by 6 Mbps optical fiber leased line using IP protocol for data transmission, for teleconference, telepathology, and teleradiology projects. We also started connection of regional cancer centers and are now forming a cancer center network of 14 cancer centers. We are at present organizing 130 teleconferences per year with an attendance of more than 16000 people as summary. We have also used a high-resolution image transferring system, such as SHD (2000 pixelsx2000 pixels resolution) system on one side, and an economical telemedicine system using JAVA and a WWW browser (NCC_image) on the other side. We think that providing information is another field of telemedicine. We began the experimental gopher and WWW service in 1993. We are now providing official up-to-date cancer information for patients and healthcare professionals. We are getting more than 400000 hits per month. We are also providing a teleconference video session which is held every week on the Internet using a Real Video system with synchronized slide presentation on the WWW browser. We are also organizing a Cancer Image Reference Database System including DICOM images with viewer software. This paper is a summary of the telemedicine projects performed at the National Cancer Center.

Restoration of tensile properties at tendon insertion to bone by a patellar tendon-tibia autograft: an experimental study with canine infraspinatus.

A free patellar tendon-tibia autograft was performed to reconstruct a tendon insertion to bone of the canine infraspinatus. In this experimental study restoration of mechanical properties at tendon insertion to bone of the patellar tendon-tibia autograft was examined on 0, 42, and 84 postoperative days. Five dogs were used for each time point. Bone union occurred in all grafts by 6 postoperative weeks. The ultimate strength at the tendon insertion to bone recovered from 255.5 N on 0 day to 264.3 N and 439.3 N on 42 and 84 postoperative days, respectively. Stiffness recovered from 141.8 KN/m on 0 day to 201.8 KN/m and 226.3 KN/mN on 42 and 84 postoperative days, respectively. Our results demonstrate that patellar tendon-tibia autograft maintains excellent mechanical properties at tendon insertion to bone in the early healing period. This result suggests that transfer or free graft of tendons with attaching bone plug has a mechanical advantage for reconstruction of the rotator cuff, which may allow the patient to institute early postoperative mobilization.

Measurement of mechanical characteristics of tibial periosteum and evaluation of local differences.

Stress-strain relationships of bovine tibial periosteum, harvested from anterior, medial, lateral, and posterior aspects of tibia, were successfully measured using a newly developed experimental system. Results showed a curvilinear stress-strain pattern having three regions, i.e., toe, almost linear, and rupture regions, which resembled those of biological soft tissues like ligaments, skin, etc. Tensile moduli in the toe region (Ee) and in the linear region (Ec) were obtained by linear regressional analyses. These values and the tensile strength (sigma t) showed clear local differences. The values of Ee, Ec, and sigma t in the longitudinal direction in the metaphyseal regions where ligaments or connective tissues attach were approximately two times larger than those in the diaphysis, where muscles or connective tissues attach. However, these properties in the metaphyseal and diaphyseal regions with muscle attachments were almost the same. In the transverse direction, these properties in the anterior proximal metaphysis were approximately two times larger than those in the diaphysis and in the distal metaphysis. In the other regions, these properties appeared not to be significantly different. These results clearly demonstrate that the mechanical properties of periosteum are strongly influenced by the ligament and muscle attachments.

Medical Internet exchange project in Japan.

The Internet has been widely used by medical institutes and hospitals around the world, however; its use for telemedicine is still low. The main reason for this is the availability of bandwidth and poor security through the net. Meanwhile, we have established and have been operating 'Cancer Information Network' among 11 Cancer Centers in Japan, mainly for Multipoint TV Conference using HDTV image. There are also similar projects among 9 cardiovascular centers in Japan. By March, all 240 national hospitals will have been connected by an IP network using an ATM backbone. The above network projects are operated independently, and have an 'Intranet' characteristics within them. There are also many hospitals and clinics connected to the Internet by commercial internet providers. To make a secure and efficient network between these medical networks and medical sites, we started the Medical Internet eXchange project (MDX project) constructing a Medical Network Operation Center to create a link between them. To provide the administrative policy of this project, we established the Medical Internet eXchange Association. We are planning to expand this project to Asian-Pacific countries using the Asian-Pacific Advanced Network (APAN), and also expand it to worldwide connections in the future. For this purpose, we are currently asking other countries to form a structure similar to MDX-Japan. The concept, hardware system, software system, firewall configuration, and routing policy will be also discussed.

An autopsy case of Cronkhite-Canada syndrome.

An autopsy case of Cronkhite-Canada's syndrome characterized by diffuse gastrointestinal polyposis, alopetia, onychodystrophia and pigmentation of the skin is reported. The patient, 51 year-old-male, died with general weakness and pneumonia at 6 months after the first notice of alopetia anorexia and weight loss. Numerous and various sized polyps and polypoid lesions were revealed in the gastrointestinal tracts at the autopsy. The microscopic pictures of the lesions were composed of hyperplastic or papillary adenomatous polyps with hyperplasia of mucosa epithelium. In some of the lesions, the glands are cystically dilated containing mucous. Lymph vessels of thelamina propria and the submucosa benerked chronic inflammatory infiltrate was noted. The present report is described the histopathological findings of the gastrointestinal lesions with Cronkhite-Canada syndrome and discussed with literature.