M66: Spontaneous rupture of synovium and tendon
M66.0: Rupture of popliteal cyst
The knee joint connects the thighbone (femur) to the lower leg. Around the knee joint is a joint capsule. The joint capsule contains synovial fluid so that the bones can glide by each other. There are also bursas in the knee. These bursas prevent tissue, for example muscles and tendons, from rubbing against each other.
Firstly, a cavity filled with fluid formed in the hollow of your knee. Such a cavity can form in the joint capsule or in a bursa in the knee. It can occur because of an inflammation or after an injury, for example.
The cavity in the hollow of your knee then burst. When a cavity in the hollow of your knee bursts, the knee may be painful.
Patient Disclaimer
The information provided on this page is for general educational purposes only. It is not intended for self-diagnosis and does not replace professional medical advice. Always consult your doctor or a qualified healthcare provider with any questions or concerns about your health.
If you see an ICD diagnosis code (e.g., on a medical report), be aware that doctors may also include additional indicators to express diagnostic certainty. Only a healthcare professional can interpret these codes accurately in the context of your individual case.
For a complete understanding of your condition and what the diagnosis means for you, please speak directly with your doctor.