Striated PDWI high signal is seen in the posterior horn of the medial meniscus, meaning that there is striated damage or inflammation in the medial meniscus, indicating that there is damage to the knee meniscus. PDWI high signal is a phenomenon that occurs on MRI, which indicates bleeding, inflammatory reaction, and infiltration of joint fluid, which results in a large amount of localized free fluid. The presence of PDWI high signal in the posterior horn of the medial meniscus indicates a striated meniscus or an inflammatory reaction that has resulted in fluid leakage into the joint. MRI examination reveals that the posterior horn of the medial meniscus can be seen as a strip of PDWI high signal, the doctor should determine the degree of damage to the knee joint based on the signs and symptoms of the posterior horn of the medial meniscus, and give the correct treatment.