**8. Conclusions**

The number of medial meniscus root tear were found more often due to better understanding of the physicians and accessibility to the investigation tool such as MRI. The important aspect of meniscus root was the stability of the whole meniscus. With medial meniscus root tear, overall hoop stress function was impaired which will lead to early-onset osteoarthritis. Most of the tear occurred in adults through a minor trauma such as squatting or sitting. The pop sound is one of the significant happenings that is frequently found. Investigation of choice was the MRI because of its high sensitivity and specificity. Significance MRI finding included cleft sign, ghost sign, and medial meniscus extrusion. Diagnosis needed index of suspicious and confirmed by the investigation. Early detection would lead to better outcome of the treatment. The longer the duration, the worse the degree of meniscus extrusion and degree of cartilage damaged. Nonoperative treatment may relieve pain and swelling in the short term. We recommend meniscus root repair in case of acute tear, or mild degeneration of the knee. Early treatment may prevent the meniscal extrusion and reduce the rate of knee replacement conversion. Biologic treatments might have a role for enhancing repair and needing further study.
