Microanatomical characteristics of arterial vascularization of the anterior cruciate ligament

Abstract

Introduction/Objective. The aim of this study was to examine the immunohistochemical features of the vascularization of the anterior cruciate ligament (ACL), as well as the quantification of capillaries within the three segments of the ACL; proximal, middle and distal. The quantification and metric characteristics of mast cells of the ACL are the second goal of this research. Methods. In total, 30 human ACL of 30 persons, obtained during routine autopsy, were examined under the microscope, following immunohistochemical reactions against CD34 of blood vessels and MastTrip of mast cells. Results. The middle genicular artery close to the ACL gave off branches for the supply of ligament itself. Each field of mm2 contained an average number of 1113.84 (959–1240), microvessels in ACL proximal third, an average number of 1145.43 (924–1310) microvessels in ACL middle third, and an average number of 1134.55 (889–1451) microvessels in ACL distal third. An average number of mast cells of the ACL was 3.8 per mm2. In the peripheral synovial zone of the ACL, we counted 12.6 mast cells per mm2. An average area value of the mast cells was 124.7 μm2, and an average value of shorter and longer axis of the mast cells was 11.2 × 15.0 μm. Conclusion. There was no statistically significant differences between the average numbers of intraligamentous microvessels of the ACL thirds (p > 0.05), confirming and supporting our hypothesis of uniform distribution of blood supply within the ACL.

Keywords

• anterior cruciate ligament
• intraligamentous microvessels
• mast cells
• immunohistochemistry