Biometría de las conexiones intertendinosas del dorso de la mano humana

Abstract

Intertendinous connections (IC) are narrow connective tissue bands extending between the extensor digitorum (ED) tendons. These bands are located superficially on the dorsum of the second, third and fourth intermetacarpal (IMC) space, presenting important functions such as collaborating in the stabilization of the metacarpophalangeal joint (MCP) and allowing the redistribution of extensor forces on this joint. The objective of the present study was to establish the biometric characteristics of IC. To do this, 24 formalized upper limbs are used, belonging to the Anatomy laboratory of the Universidad Andrés Bello, Viña del Mar, Chile. Lateral and medial insertion lengths, width and total length of each IC were recorded. Following two criteria, IC were classified according to morphology and were also located according to thirds of the back of the hand. 69 IC were found, 39 % presented a transverse arrangement and 61 % an oblique arrangement. In relation to the morphological classification of IC, 29 % of type 1 were identified, 39 % of type 2. In the case of type 3, 20 % presented the form “r” and 12 % the form “y”. Regarding its location, it was established that in the second IMC space, 18 % of the IC were located in the distal third of the back and 82 % in the middle third. In the third IMC space, 96 % of the IC was located in the distal third and 4 % in the middle third. In the fourth IMC space, 96 % were located in the distal third and 4 % in the middle third. Considering the biestiloid line as a reference, the IC in the second IMC space considers an average width of 8.16 + 1.94 mm and an average total length of 13.71 + 4.70 mm. In the third IMC space, an average of 10.94 + 4.39 mm for the width and 6.29 + 3.26 mm of average total length. In the fourth IMC space the average total width of 7.00 + 3.06 mm and the average total length of 7.08 + 4.42 mm. These findings provide data regarding the biometrics and location of IC, which is useful in surgical repair procedures on the back of the human hand.