Abstract: | Sixty human hands from adult cadavers were used to study the chiasma tendinum (Camper) of the flexor digitorum superficialis tendon in the finger. Two hundred forty fingers were microdissected and examined morphometrically. The formation of the chiasma tendinum could be divided into nine types. The most common type shows that the flexor digitorum superficialis tendon divides into four bundles, the two inner of which cross each other. The length and width of the chiasma tendinum in the middle finger is the longest and widest, while in the little finger it is the shortest and narrowest. The relationship of the chiasma tendinum and the long vinculum of the flexor digitorum profundus tendon was also observed in the present study. In the most common type the long vinculum lies distal to the chiasma lying between the two terminal tendons of the flexor digitorum superficialis. The authors suggest three functions for the chiasma tendinum: (1) it provides a pathway for the flexor digitorum profundus tendon; (2) it increases the stability and balance of the proximal interphalangeal joint; and (3) it prevents hyperextension of the proximal interphalangeal joint. © 1994 Wiley-Liss, Inc. |