Bone marrow edema is a sign with bone matrix edema, fibrous tissue hyperplasia and inflammatory cell infiltration as the main pathological manifestations. With the development of technology and the widespread use of MRI, the sign of bone marrow edema has gradually been recognized, but it has not attracted widespread attention until recent years when some scholars have reported relevant studies. The causative factors of bone marrow edema are still uncertain, including: trauma, hormones, and mechanical stress alterations. Biomechanical alterations are one of the causes of bone marrow edema, and mechanical stress may play an important role in the development of bone marrow edema. Mechanical stress alterations lead to trabecular fractures in the weight-bearing area and the development of bone marrow edema. MRI is currently the best means of diagnosing and evaluating bone marrow edema. The degree of pain is consistent with the severity of bone marrow edema, and as the severity of bone marrow edema decreases with MRI, the patient’s pain decreases accordingly, specifically in this case it should be a patellofemoral problem, caused by the increased stress on the patella due to excessive repetitive knee flexion activities, which is rare and easily misdiagnosed. Bone marrow edema syndrome usually occurs in the hip joint.