Abstract: as three kinds of medical devices, nickel titanium alloy grasping bone plate is implanted into the human body for a long time, and its product safety is very important. Therefore, risk management of nickel titanium alloy products is particularly important. According to the requirements and regulations of YY / t0316-2008 and iso14971-2007, the risk management of NiTi alloy grasping bone plate is carried out. Find out the risk points of the product and control them. Ensure that the risks in the process of future production, sales and use are minimized.

　　Key words: nickel titanium alloy; Risk management; harm; Risk analysis; Risk Management

　　As a kind of shape memory alloy, nitinol alloy has an expansion rate of more than 20% and a fatigue life of 1 × 107. The damping characteristic is 10 times higher than that of ordinary springs, and its corrosion resistance is better than the best medical stainless steel at present. Therefore, it can meet the application needs of various engineering and medicine. It is a very excellent functional material. In addition to its unique shape memory function, memory alloy also has the excellent characteristics of wear resistance, corrosion resistance, high damping and hyperelasticity. It can also meet the requirements of chemistry and biology, that is, good biocompatibility. Nickel titanium alloy can form a stable passive film with organisms. Therefore, nickel titanium alloy has been developed into many medical device products. At present, most of the medical device products developed and put into market application are more class II and class III medical devices, some of which are implanted into the human body, and placed in the body for a long time. Therefore, risk management of nickel titanium alloy products is particularly important. Risk management of its products will be carried out in accordance with the requirements of medical device risk management standards and procedures.

　　1、 Determination of intended use and safety related characteristics of nitinol alloy grasping bone plate

　　Intended use: it is mainly used for fracture internal fixation of bone injury patients to help patients with early healing and functional exercise. Nitinol alloy grasping plate is a new type of internal fixation instrument for tubular bone fractures of limbs. It uses the shape memory effect of nitinol alloy to realize the circumferential embracing fixation mode of tubular bone of limbs. Its advantage is that the operation is convenient and simple; The fixation and holding are firm and reliable, which conforms to AO and Bo fixation theory; The material has good biocompatibility and is an ideal internal fixation implant material. The product is provided to the user in a non sterile state. The hospital doctor organizes disinfection before operation, and supports each embracing arm under ice saline to make it larger than the outer diameter of the bone, which is convenient for clamping into the fracture part. After adjustment and reduction, heat with warm saline to promote the reduction and holding of the embracing arm. This product is disposable and can effectively avoid cross infection between patients.

　　2、 Judgment of visible or potential hazards

　　After preliminary analysis, the judgment of relevant potential hazards is as follows: (1) damage to patients: bacteria, leading to pyrogen reaction or infection, and death in serious cases. Improper model selection leads to unreliable fixation and secondary fracture. After being loaded into the human body, it is adjusted repeatedly, resulting in the loss of the function of the product. The microcrack defect in the finished product causes crack propagation and failure after the patient is loaded. The doctor did not follow the steps and forced deformation, resulting in incomplete shape recovery and failure. The patient did not follow the training instructions of the doctor after the operation and carried the weight prematurely, resulting in fatigue fracture of the instrument and malunion of the bone. Due to the thin wall of the instrument material or insufficient material strength, the patient's end function recovers, resulting in the fatigue deformation of the instrument, resulting in bone malunion or false healing. The inaccurate setting of the functional temperature of the instrument leads to premature shape recovery or slow shape recovery, resulting in delayed operation. (2) Damage to the user: the sharp teeth are too sharp and cut the patient's tissue or the operator's hand. The supporting equipment for taking out is insufficient, resulting in cumbersome secondary taking out. The device has no memory function and cannot be used normally. The memory function of the device has been artificially damaged and cannot be used normally. Hazards related to use, resulting in incorrect use.