Association Between Patient Characteristics and the Depth of Microvascular Penetration Into the Adult Human Meniscus

Current knowledge on the microvascular anatomy of adult human menisci is based on cadaveric studies. However, considerable interindividual variation in meniscal microvascularization has been reported in recent studies with small sample sizes.

To assess the association between patient characteristics and the depth of microvascularization of the meniscus.

Descriptive laboratory study.

Menisci from 174 patients who received total knee replacement between March 2021 and December 2023 were collected. A total of 174 lateral and 102 medial menisci were included. Three sections were made from each meniscus: the anterior horn, midbody, and posterior horn. Immunohistochemical staining (CD-31) was used to visualize the microvasculature. The 4 primary outcome measures were the correlation between the depth of microvascular penetration into the lateral meniscus (0%-100%) and (1) age, (2) smoking, (3) degree of osteoarthritis, and (4) history of cardiovascular disease. To account for repeated measurements within each patient, a linear mixed-effects model was estimated to study the association between microvascularization and the patient's characteristics previously introduced.

The depth of vascular penetration ranged from 0% to 78% into the lateral menisci and from 0% to 67% into the medial menisci. No significant correlations were found between age, smoking, degree of osteoarthritis, or history of cardiovascular disease and the degree of vascular penetration into the lateral meniscus. The linear mixed-effects model analysis, adjusted for location within the meniscus (anterior horn, midbody, or posterior horn) and meniscal side (lateral or medial), showed no significant associations between the same patient characteristics and meniscal microvascularization.

The degree of microvascular penetration into the meniscus has a wide range among adults >50 years. However, the depth of microvascularization was not associated with age, smoking, degree of osteoarthritis, or history of cardiovascular disease.

Because no associations were found between depth of microvascular penetration into the meniscus and patient characteristics, the latter cannot be used to estimate the vascular status of a meniscal tear in clinical practice.