Biomedical subjects

Takamitsu Arakawa

Publications and source records attributed to Takamitsu Arakawa.

4 recordsLinked to original sources

PubMed2006

Intramuscular nerve distribution pattern of the oblique and transverse heads of the adductor hallucis muscles in the human foot.

To understand which layer of the intrinsic muscles of the foot the adductor hallucis muscle belongs to, it is essential to investigate the innervation patterns of this muscle. In the present study, we examined the innervation patterns of the adductor hallucis muscles in 17 feet of 15 Japanese cadavers. We investigated the intramuscular nerve supplies of the adductor hallucis muscles in six feet and performed nerve fiber analysis in three feet. The results indicate that: (i) the oblique head of the adductor hallucis muscle is divided into three compartments (i.e. lateral, dorsal and medial parts) or two compartments (i.e. dorsal and medial parts) based on its intramuscular nerve supplies, but we could not classify the transverse head into any parts; (ii) the communicating twig between the lateral and medial plantar nerves penetrated the oblique head of the adductor hallucis muscle in 13 of 17 feet (76.5%); (iii) the penetrating twig entered between the lateral and dorsal parts of the oblique head, passed between the lateral and medial parts of this muscle and then connected with the medial plantar nerve; and (iv) the majority of the nerve fibers of the penetrating twig derived from the lateral plantar nerve. The present study demonstrated that only the lateral part of the oblique head of the adductor hallucis muscle had a unique innervating pattern different from other parts of this muscle, suggesting that the lateral part of the oblique head has a different origin from other parts of this muscle.

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PubMed2005

Ramification pattern of the deep branch of the lateral plantar nerve in the human foot.

To understand how the oblique and transverse heads of the adductor hallucis muscle of the human foot are phylogenitically and ontogenetically developed, it is essential to know nerve supplies of these two heads of the muscle. In the present study, we dissected seven feet of five Japanese cadavers in detail to clarify the ramification patterns of the deep branch of the lateral plantar nerve by peeling off its epineurium (the nerve fascicle analysis method). We found that the muscular branch to the oblique head of the adductor hallucis muscle directly separated from nerve fascicles constituting the deep branch of the lateral plantar nerve, whereas the muscular branch to the transverse head arose in common with branches which innervated other intrinsic muscles of the foot, i.e., the 2nd and 3rd lumbrical muscles and the 1st and 2nd dorsal interossei muscles. The present study revealed that two heads of the adductor hallucis muscle, the oblique and transverse, had different innervating patterns, suggesting that two heads of the human adductor hallucis muscle develop from different primordia, and not from common ancestors.

Cadaver↗

PubMed2004

[Modified grant method protocol for dissecting and identifying the brachial plexus].

Dissection of the brachial plexus is an important part in the anatomical course, but it is difficult for medical students to identify individual nerves of the brachial plexus due to its complexity and numerous variations. We have recently adopted the Grant method (1991) to guide students in the successful identification of this plexus. However, according to the Grant method the part of the upper limb including the brachial plexus is dissected before the neck part, which makes it impossible to identify the roots, trunks, and cords of the brachial plexus, and to identify the nerve branches extending from the brachial plexus. Here, we propose of anatomical dissection protocol of the brachial plexus a modified Grant method for medical students and instructors. The points of the modified protocols are: (1) to dissect the brachial plexus after the dissection of the neck part, (2) to identify the nerve trunks at the scalenus gap after dissecting the lateral, medial and posterior cords. The modified Grant method can be adapted to any other dissecting protocol of the brachial plexus, and will allow students to cope with many variations of the brachial plexus when they occur.

Anatomy↗

PubMed2003

Anatomical study of human adductor hallucis muscle with respect to its origin and insertion.

The adductor hallucis muscle (ADH) is evolutionally and functionally important, but no detailed morphological data about this muscle in the human body is available. In the present study, we examined the origin and insertion of the oblique and transverse heads of the ADH. Forty-five feet (20 right, 25 left) of 34 cadavers (13 men, 21 women, average age of 80 years old) were used in the present study. The origin, insertion and nerve supplies of the oblique and transverse heads of the ADH were macroscopically examined in detail. Most commonly, the oblique head of the ADH arose from the bases of the 2nd, 3rd and 4th metatarsal bones, the plantar metatarsal ligaments spanned between the bases of the 2nd, 3rd and 4th metatarsal bones, the lateral cuneiform bone, the fibrous sheath of the tendon of the peroneus longus muscle and the long plantar ligament, and inserted into the lateral sesamoid bone of the great toe and the capsule of the 1st metatarsophalangeal joint. Most commonly, the transverse head of the ADH originated from the capsules of the 3rd and 4th (and occasionally 5th) metatarsophalangeal joint and the deep transverse metatarsal ligaments, and inserted into the lateral sesamoid bone of the great toe, the capsule of the 1st metatarsophalangeal joint and lateral surface of the base of the 1st proximal phalanx. This muscle was classified into four types based on the origin of its oblique head and was classified into three types based on the origin of its transverse head. The percent ratio of the weight of the oblique head to the total weight of all the intrinsic muscles of the foot was 9.4% +/- 1.5, and the transverse head was 1.5% +/- 0.6 (n = 14). The transverse head of ADH tends to be reduced in size in the human, but the oblique head is well developed with no sign of reduction.

Aged↗