A collapsed knee refers to a condition where the joint surface of the knee has broken down, depressed, or flattened, often due to underlying bone damage.
Understanding Knee Collapse
Knee collapse isn't a specific diagnosis but a description of the state of the knee joint. It's often associated with conditions that cause the bone underneath the cartilage to weaken and die, leading to a breakdown of the joint surface.
Causes and Related Conditions
- Osteonecrosis: According to the provided reference, a collapsed knee is a characteristic of stage III osteonecrosis, where the joint surface has collapsed and become depressed or flattened. Routine x-rays can usually detect this collapse and irregularity. Osteonecrosis happens when blood supply to the bone is disrupted, causing the bone to die and eventually collapse.
Diagnosis and Detection
- X-rays: Routine X-rays can show a collapsed and irregular joint surface.
- MRI: MRI scans can reveal damage to the articular cartilage overlying the collapsed bone, which is often not visible on routine X-rays.
Table Summarizing Collapsed Knee
| Feature | Description |
|---|---|
| Definition | Joint surface collapse, depression, or flattening in the knee. |
| Primary Cause | Underlying bone damage, often from osteonecrosis. |
| Detection Methods | X-rays (for bone changes), MRI (for cartilage and soft tissue damage). |
| Association | Often associated with Stage III osteonecrosis. |
Implications of a Collapsed Knee
A collapsed knee signifies significant damage to the joint and often results in pain, reduced mobility, and functional impairment. It usually necessitates intervention to manage pain and restore function, which may include conservative treatments or surgical procedures like knee replacement in severe cases.
