Origin of the dorsal scapular artery and its relation to the brachial plexus in Thais.

We investigated the variations of the origin of the dorsal scapular artery (DSA) and its relation to the brachial plexus in 252 sides of the posterior cervical triangles of Thais. The origin of this artery on each part of the subclavian artery or other arterial branches was examined with special reference to their course in relation to the brachial plexus. The results show that the DSA originated from three sites; most commonly from the transverse cervical artery (69%) followed by the direct branching from the second (2.8%) or the third part (28.2%) of the subclavian artery. When the DSA was branched from the transverse cervical artery, its course was always posterior or above the brachial plexus. When the DSA arose from the second or the third part of the subclavian artery, it always ran in the branches of the brachial plexus in various sites. The most frequent course was to pass between the upper and middle trunks of the brachial plexus (63.2%). Other courses were far less frequent and found to pass between the anterior division of the upper trunk and the middle trunk of brachial plexus or between the roots of C8 and T1 with the frequency of 1.3 and 2.6%, respectively.

Geometry of carpal scaphoid in Thais: anatomical study.

In order to develop new surgical techniques on, and fixation devices for, carpal scaphoid fractures in Thais, the authors determined the mean and standard deviation of the length, width and thickness of 141 carpal scaphoid bones on 93 left and 48 right wrists from the skeletons of 99 Thai males and 42 Thai females. The deceased averaged 60 years (range, 22 to 89). The scaphoid length averaged 25.59 mm; the dorsal width at the distal, middle and proximal poles averaged 14.89, 10.23 and 7.08 mm, respectively; the palmar width at the distal, middle and proximal poles averaged 14.22, 9.81 and 7.44 mm, respectively; and the thickness at the distal, middle and proximal poles averaged 9.77, 10.96 and 9.19 mm, respectively. The authors found no signficant difference (p = 0.96) in the length and width of the Thai carpal scaphoid bone between the left and right wrist. The widths of the dorsal and palmar sides at the distal end were wider than the proximal end and tapered from the distal to the proximal pole. The thicknesses were constant throughout the length of the bone, ranging between 9 and 11 mm.