M65-M68: Disorders of synovium and tendon

M66: Spontaneous rupture of synovium and tendon

Spontaneous rupture of synovium and tendon refers to a group of conditions where the protective layers around a joint or tendon suddenly break or tear without any apparent cause, like injury or trauma. This group of conditions typically affects the body's musculoskeletal system. Symptoms may include sudden pain, joint swelling, difficulty in moving the affected area, and in certain cases, a noticeable lump or bump under the skin. The ruptures can occur in any joint or tendon, but they're particularly common in the knee, shoulder, elbow, and wrist. The exact reason for these ruptures is not clear, but factors like age, disease-related weakening of the synovium or tendon, or previous injury may play a role. Over time, untreated ruptures can lead to decreased joint functionality and movement restrictions.