[Fascicular and sub-fascicular architecture of the cruciate ligament]

The details of the collagen fascicle morphology and the vascularization of the anterior and the posterior cruciate ligament were examined by the combined use of histology, transmission- and scanning electron microscopy, morphometry and immunohistochemistry. The diameters of the collagenous fibrils in the anterior cruciate ligament ranged between 20 and 155 nm (x = 74 nm, s = 18.8 nm) and in the posterior cruciate ligament between 20 and 175 nm (x = 82 nm, s = 25.4 nm). Type III and VI collagen were found distributed throughout the matrix but concentrated in the attachment regions of the ligaments. The content of type IV collagen in the anterior cruciate ligament was low. The amount of arterioles revealed a typical pattern (anterior cruciate ligament: less than 30 years = 2.94/mm2, greater than 90 years = 2.02/mm2, proximal = 3.15/mm2, distal = 2.18/mm2; posterior cruciate ligament: less than 30 years = 4.69/mm2, greater than 90 years = 3.87/mm2, proximal = 4.08/mm2, distal = 3.98/mm2).