Orthotics are very common in the rehabilitation of cerebral palsy, and many parents who have rehabilitated their children in the hospital should not be unfamiliar with them, but many parents are not sure what orthotics are for, whether their child should or should not be fit with orthotics, and what kind of orthotics should be chosen. Here I will give you a brief explanation of what orthotics are, as well as common lower limb orthotics and their indications. First we need to know what an orthotic is. Orthotics (Orthosis), also known as braces, are devices that are applied to the human limbs, trunk and other parts of the body to prevent, correct deformities and compensate for some or all of the functions of the bones and muscles through the action of force. Its role can be summarized as stability and support, fixation and protection, prevention and correction, weight-bearing and improvement or compensation of function. Then the common orthotics we can simply be divided into upper limb orthotics, lower limb orthotics, spinal orthotics according to the assembly parts. Here I will briefly introduce the lower limb orthotics and their corresponding suitability for children with cerebral palsy in which symptoms. 1. Foot orthoses, including foot braces, foot cushions, and orthopedic shoes. The trailing edge of the foot orthosis, especially the foot rest, generally does not exceed the ankle joint, and most of the foot pads are used in conjunction with the foot rest and orthopedic shoes. Foot orthoses are mainly used for children with cerebral palsy who have mild internal and external rotation of the foot, arch collapse, lower limb dysplasia with long and short legs but can walk independently and have good toe flexion and dorsiflexion of the foot. 2.Ankle-foot orthosis, including ankle-foot orthosis, flexible ankle-foot orthosis, dynamic ankle-foot orthosis. The rear edge of the ankle-foot orthosis generally does not exceed the calf, where the hard ankle-foot orthosis is made of plastic shell with polyethylene sponge or silicone, which restricts the movement of the ankle joint in all directions, including the inward and outward turning of the ankle joint. The width of the Achilles tendon area is trimmed to fit the child. It is primarily used for children who are able to walk to correct heel deformities and prevent abnormal ankle movements during walking. Dynamic ankle-foot orthosis is the most widely used orthosis, it is equipped with dynamic hinges or movable rivets at the ankle joint of the orthosis, which not only has the advantages of a rigid ankle-foot orthosis, but also can keep the child’s foot with a certain degree of dorsiflexion and toe flexion, mainly for children with cerebral palsy who have mild spasticity, whose foot inversion is not very serious and whose foot deformity can be easily corrected. 3.Knee ankle foot orthosis, this type of orthosis is mainly composed of metal hinge and plastic shell, the trailing edge of which exceeds the knee joint below the transverse hip line, including free motion knee hinge and adjustable knee hinge, it is mainly applied to children with cerebral palsy who have knee hyperextension and lateral movement of the knee joint in standing and walking, and also have ankle foot deformity and abnormal movement but can stand or walk. 4.Knee orthosis, which is similar to the knee-ankle-foot orthosis but without the part below the calf of the knee-ankle-foot orthosis, is mainly used for children with cerebral palsy who have hyperextension of the knee joint and lateral movement of the knee joint in standing and walking, but do not have ankle-foot deformity and abnormal movement but can stand or walk. 5, hip, knee, ankle and foot orthoses, mainly for the control of hip abduction and abnormal rotation of the lower limbs, this type of orthoses are less used, not detailed here Through the above introduction, parents should be able to understand whether their children are suitable for orthoses, what kind of orthoses should be done. Here I would like to remind parents that they cannot rest easy with orthotics, but the root of the problem is the rehabilitation of the child with cerebral palsy. Therefore, parents should carry out rehabilitation functional training under the advice and guidance of rehabilitation therapists and rehabilitation doctors, and properly cooperate with the orthotic wear, so as to achieve a more ideal rehabilitation effect.