Non-rotation of the midgut in adults.

Two cases of non-rotation of the midgut were detected in cadaveric bodies from the Department of Anatomy, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand. They were both female, aged 83 and 32, respectively. In both cases, the duodenum, jejunum, ileum, and colon lay in the unrotated position with the small intestine occupying the right half and the large intestine occupying the left half of the abdominal cavity. Additionally, the duodenojejunal junction remained on the right side of the abdomen, whereas the caecum and ascending colon lay in the midline, with the terminal ileum entering the right side of the caecum. The appendix entered the left side of the caecum. Interestingly, they had had no clinical symptoms during life. These abnormalities implied that midgut rotation during embryonic period occurred only as far as 90-degrees counterclockwise instead of the usual 270-degree rotation. To our knowledge, this is the first report of asymptomatic non-rotation of the midgut in Thailand. The variation found in the present study provides additional information concerning the variation seen in human anatomy and should be considered in patients with atypical symptoms related to the gastro-intestinal tract.

The relation of the maxillary artery and the origin of the middle meningeal artery in Thais.

A study of the relationship of the maxillary artery to the lateral pterygoid muscle was performed upon 306 sides of 153 Thai cadavers; 84 males and 69 females. Most arteries were found lateral to the lateral pterygoid muscle in 275 sides (90%), and the remainder medial to this muscle. Additionally, the origin of the middle meningeal artery was observed to originate proximally 64%, opposite 18%, and distally 8% to the origin of the inferior alveolar artery when the maxillary artery passed laterally to the lateral pterygoid muscle. On the other hand, it was found that this artery originates proximally 4%, opposite 1%, and distally 5% to the origin of the inferior alveolar artery when the maxillary artery passed medially to the lateral pterygoid muscle. The accessory meningeal artery was presented in 71%. The result of this study will be useful in surgery.

The clinical anatomy of commonly injured muscle bellies of the upper extremities in Thais.

Cadaver specimens of commonly injured muscle bellies of the upper extremities were examined for the presence, location and extent of the origin and insertion. These muscles were the pectoralis major, biceps brachii (long head), triceps brachii (long head), brachioradialis, extensor carpi radialis longus, extensor carpi radialis brevis, extensor digitorum, flexor carpi radialis and flexor digitorum superficialis. Some tendons were found to lay superficially on the surface of fleshy fibres and some tendons extended deeply into the muscle. Most of the muscle bellies contained tendinous extensions that appeared as flattened fibrous bands. This study provideds anatomical information as to the approximated location and extent of these tendons to permit optimal surgical repair.