Histological analysis of age-related degeneration in human female and male knee cartilage and meniscus

TL;DR

This study examines how knee cartilage and meniscus degenerate with age in people without arthritis, finding that degeneration increases with age and is slightly more severe in males.

Contribution

The study provides new insights into age-related degeneration in knee tissues without clinical arthritis, highlighting sex differences and weak tissue associations.

Findings

Degeneration in knee cartilage and meniscus increases with age in individuals without arthritis.

Male sex is associated with slightly higher levels of degeneration in both tissues.

Cartilage and meniscus degeneration are only weakly associated in knees without arthritis.

Abstract

To assess level of degeneration in human knee cartilage and meniscus in donors without clinically-evident knee arthritis, in relation to age and sex. Further, to investigate the association between cartilage and meniscus degeneration.

Histological sections of knee cartilage and meniscus from 44 deceased donors (ages 18–85 years) without clinically-evident osteoarthritis or inflammatory arthritis were assessed for the level of degeneration using OARSI grades (cartilage) and modified Pauli scores (meniscus). We used Poisson regression models with robust standard errors to investigate the association of age and sex with grades/scores, and the association between cartilage and meniscus degeneration.

Mean [median] (standard deviation) OARSI grade and Pauli score were 2.2 [1.8] (1.2) and 8.2 [8] (2.5), respectively. The mean OARSI grade increased by a factor of 1.19 (95 % confidence interval 1.11 to 1.28) per 10 years of age, and the Pauli score by 1.10 (1.07–1.14). Males had on average 1.29 (0.99–1.69) higher OARSI grades than females, and 1.11 (0.96–1.28) higher Pauli scores. The crude association between Pauli score and OARSI grade was 1.12 (1.05–1.18), while the age and sex adjusted association was 1.06 (0.99–1.13).

Tissue degeneration assessed by OARSI grades and modified Pauli scores increase with age in persons without clinically-evident knee arthritis. However, about half of the elderly donors show only mild degeneration. There was a small association between degeneration and male sex, for both tissues. Cartilage and meniscus degeneration within knees without clinically-evident arthritis were weakly associated.

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