Subchondral bone and cartilage disease: a rediscovered functional unit.

Area of Science:

• Orthopedics
• Biomedical Engineering
• Cartilage Research

Background:

• Subchondral bone's role in cartilage damage is underestimated.
• It functions as a shock absorber and influences cartilage metabolism.
• The subchondral region is highly vascularized, with vessels supplying cartilage nutrients.

Purpose of the Study:

• To highlight the underestimated role of subchondral bone in cartilage damage.
• To explain the vascular supply and metabolic contribution of subchondral bone to cartilage.
• To explore how variations in subchondral bone characteristics influence joint pathology.

Main Methods:

• Review of existing literature on subchondral bone and cartilage pathology.
• Analysis of vascularization and metabolic contributions of subchondral bone.
• Comparison of pathological outcomes in different joints under similar stress.

Main Results:

• Subchondral bone perfusion supplies over 50% of cartilage's glucose, oxygen, and water.
• Differences in subchondral bone structure and vascularization lead to varied responses to stress.
• Common etiological pathways link osteonecrosis, osteochondritis dissecans, and degenerative disease.

Conclusions:

• Subchondral bone is critical for cartilage health and metabolism.
• Variations in subchondral bone can predispose joints to specific pathologies like osteonecrosis or degenerative disease.
• Understanding subchondral bone's role is key to addressing cartilage damage and joint degeneration.