Wiki how does this report indicate the meniscal tears are due to an old tear?

[The Angel Of the South]

BRIEF SUMMARY: This lady had a previous partial meniscectomy for a discoid lateral meniscus in 19XX. She has done well until the past two or three months, when she has had gradually increasing pain. She clinically had findings consistent with an internal derangement. A MRI scan was performed, which shows complex posterior horn lateral meniscus. She is now admitted for meniscectomy.

FINDINGS OF SURGERY: A small flap tear in the mid anterior portion medial meniscus was encountered, as well as a flap tear in the midportion lateral meniscus and an inferior cleavage tear of the posterior horn of the lateral meniscus. The overall meniscus appeared satisfactory and stable. There were no peripheral tears. Partial meniscectomy performed medially and laterally. There was also synovial scarring from the opened procedure.

From this, I was supposed to have figured out, but didn't, that the new meniscal tears were due to an old tear. I vaguely understand that the key would be mostly the first sentence, but I'm having trouble explaining it clearly to myself.

Diagnosis Rationale: The patient was diagnosed with a tear of the posterior horn of the lateral meniscus and the anterior horn of the medial meniscus due to an old tear, as well as a midportion lateral meniscus tear.