Rubble cyst
A rubble cyst or debris cyst is the result of deep bone damage in the joint. As a rule, it represents a depression filled with fluid due to damage extending into the medullary canal. The causes are usually traumatic damage or osteoarthritis due to joint wear.
Rubble cysts are one of the X-ray signs of advanced osteoarthritis .
Emergence
In younger people, mainly sports accidents show such bone damage to a joint, which is then also referred to as a comminuted cyst.
Secondary articular cartilage lesions: In older people, slow abrasion (wear) of the sliding cartilage layers of a stressed joint dominates. If its protective layer is used up, the joint bones rub against each other unprotected, infiltrate into one another and cause osteoarthritis.
In both cases, holes appear, either suddenly or slowly, in the hard top layer of the joint-forming bone ( cortex ). Pieces of cartilage and synovium then slowly reach the underlying bone and are broken down by the sprouting vascular connective tissue. The result is depressions filled with decaying tissue residues with calcified borders.
After primary lesions and secondary lesions of the articular cartilage, the following happens: After the medullary cavity has been opened by primary or secondary damage, blood vessels, fibroblasts and connective tissue fibers penetrate inwards from the joint surface and initially cause a loose scar with granulation tissue, which closes the bone lesion.
source
- Roche Lexicon Medicine, 5th edition
