The reason why the joint is still not straight even after twenty days of reset may be due to joint adhesion, fracture block stuck in the joint, accompanied by joint capsule damage and no functional exercise during the recovery period of immobilization. 1. Joint adhesion: due to long time fixation of the diseased limb, the venous and lymphatic reflux is not smooth, the plasma cellulose exudation and fibrin deposition in the tissues around the joint occurs cellulose adhesion, and at the same time, the joint capsule and the surrounding muscle contracture, which leads to impaired joint movement, stiffness of the joint, and the manifestation of the failure to straighten the joint. 2. Fracture block stuck in the joint: patients with dislocation and fracture at the same time, it is easy to cause the extension not straight after reset, and sometimes the fracture block is stuck in the front of the joint or in the center of the joint, which leads to the restriction of the joint movement of the patients. 3. Accompanied by joint capsule injury: When there is a tear of the joint capsule at the same time of the injury, resulting in localized soft tissue swelling, it is very likely that the patient will not be able to straighten the joint after reset, and the patient will be afraid of straightening the joint because the damage to the joint capsule has not healed in the process of straightening. 4. Functional reset is not achieved: if the joint is not functionally reset during the reset or if it is completely reset after the reset due to inappropriate activities that lead to subluxation, the joint that is not functionally reset will lead to impaired mobility, and the joint will not be straightened. If you can’t straighten the joint after 20 days of reset, you need to improve the detailed examination under the professional guidance of orthopedic doctor to clarify the cause and do the treatment accordingly.