A Cadaveric Study of the Juncturae Tendinum

Abstract

Abstract Introduction The superficial extensor tendons of the fingers are connected by juncturae tendinum (JT). JTs are of three types namely JT-1, JT-2, and JT-3. JT-3 are very thick with maximum occurrence in fourth intermetacarpal space (IMCS), where it is associated with agenesis of extensor digitorum communis to small finger (EDCs). Awareness of frequency and morphology of JT is essential in surgical repair of tendon injury. Methods JTs were dissected in 80 free adult cadaveric upper limbs and 32 fetal upper limbs of 16 stillborn and embalmed fetuses present in the department. The pattern and frequency of JT was studied. Frequency of JT-3 in association with agenesis of EDCs was looked into. The length and width of JT were measured and analyzed using ANOVA and post hoc analysis. Results JT-1 and JT-2 were commonly observed in the second and third IMCS, respectively. JT-3 had a maximum frequency in the fourth space and was observed in 78.37% of cases of agenesis of EDCs. A gradual increase in length and a decrease in the width of JT were observed from JT-1 to JT-2, JT-3r, and JT-3y. Conclusion JTs are absent in the first IMCS and in 6.25% of second IMCS. The commonest pattern of distribution of JT in the second, third and fourth IMCS is JT-1, JT-2, and JT-3, respectively. JT-3 is the longest and thickest JT, and partially compensates for agenesis of EDCs. The structural resemblance to tendons enables JT-3 utilization for a tendon graft.