2004 Volume 44 Issue 1 Pages 35-46
Five forelimbs of four mungooses were dissected to study the precise form of the brachial plexus, to clarify the structural characteristics of the brachial plexus in phylogeny, and to decide the dorso-ventral division of the suprascapularis nerve. The following results were obtained:
1. Although the brachial plexus was composed of C5-T1, the main portion of all brachial plexus were C7-T1 because C5-6 were only connected by a thin branch.
2. The supraspinatus muscle extended not only to the lateral (dorsal) but also the medial (ventral) aspects of the scapula in all cases.
3. In 2 of 5 cases, the supraspinatus muscle originated from the cranial portion of the supraspinatus fossa in addition to the ordinary origin.
4. The suprascapularis nerve which innervated the supra- and infraspinatus muscles was bifurcated from the central region of C6.
Consequently, the suprascapularis nerve of the mungoose included both of the ventral and dorsal division of the spinal components. These results show the possibility that the human suprascapularis nerve may include both divisions.
