Supracondylar humerus fracture is a common elbow fracture in children with few indications for surgery, except for open injuries, multiple injuries, and those with obvious vascular-neural combined injuries, which were mostly treated non-operatively in the past; in order to reduce the occurrence of related complications, accurate repositioning is now advocated. Closed reduction percutaneous needle internal fixation has become the preferred treatment method. However, for some supracondylar fractures of the humerus with heavy soft tissue injury, obvious local swelling, and poorly palpable bony landmarks, it poses difficulties for percutaneous needle internal fixation, and there is a high risk of medically induced ulnar nerve injury if needle fixation is performed reluctantly. Surgical repositioning causes less damage to the soft tissues of the elbow, avoids the possible secondary injury to the vascular nerve that may occur with manual repositioning, decompresses the local area, reduces the pressure on important tissues, and minimizes the chance of osteofascial compartment syndrome with the compression of blood vessels and nerves by the anterior elbow hematoma after manual repositioning. In addition, the time required for external fixation is greatly reduced compared with that required for manual repositioning, which makes it easy for early active exercise and promotes early recovery of limb function. Elbow inversion is a major complication of supracondylar humerus fracture, and the mechanism of its occurrence is not very clear. There are four surgical approaches to supracondylar humerus fractures: posterior, anterior, lateral and medial approaches. In the posterior approach, the triceps tendon is incised and fixed under direct vision, which can protect the ulnar nerve. It can clearly expose the surgical field and better reposition the fractured end anatomically, but the surgery is traumatic and often results in scar adhesions around the elbow joint, leaving varying degrees of flexion and extension dysfunction. The anterior approach to the elbow is not sufficiently exposed, and it is difficult to achieve anatomic repositioning. The medial elbow incision can protect the ulnar nerve well on the ulnar side and reveal the ulnar side completely, reducing the chance of elbow inversion in the future. In addition, because the incision is medial, it is more concealed and more beautiful, which meets the aesthetic requirements of modern people.