Synovitis of the hip joint in children, also known as synovitis of the hip joint, temporary synovitis of the hip joint, simple synovitis, misalignment of the hip joint in children, misalignment of the acetabulum in children, flashing hip, hip drop ring in children, subluxation of the hip joint in children, pseudo-dislocation, this disease belongs to the category of paralysis, hip joint injury. The doctor adopts a comprehensive treatment of manual repositioning, and now excerpts some of the contents for the reference of the patient’s parents, in order to draw attention to avoid lifelong regrets. This disease was first reported by Loveit in 1892, and is a common disease of the soft tissue of the hip in children. It is thought to be a self-limiting disease of the hip that follows a cold, dysentery, laryngitis, asthma, measles, rhinitis, pneumonia, etc. Recently, the disease is considered to be a relatively common toxic, immune reactive or allergic disease. It is also believed that the effects of chronic cumulative damage, such as excessive walking, fatigue or minor trauma, should not be excluded. Most children have a history of strenuous activity such as jumping, skipping and running, and most have no history of trauma, and most have a slow onset, with less than half having an acute onset. The hip joint is painful, afraid to flex the hip and limp, but often can limp and play. The pain is often accompanied by pain in the ipsilateral medial thigh and knee joint, and is aggravated by passive internal and external rotation of the hip. At present, there is no uniform understanding of the pathogenesis of this disease in either modern medicine or Chinese medicine. It is generally believed that the disease is caused by upper respiratory tract infection, with congestion and edema in the synovial membrane and translucent exudate in the joint. It is also believed that the etiology of the disease is based on the possibility of an antibody response. Since the intra-articular membrane is a special differentiated tissue that is sensitive and intense to physical, mechanical, chemical, and biological stimuli, and the clinical symptoms are caused by this response, the disease is considered to be a non-specific inflammatory disease with a self-limiting tendency. In Chinese medicine, the disease is thought to be caused by trauma, and the small movement between the femoral head and the acetabular fossa is called “pediatric hip joint misalignment”. According to clinical observation, some people think that this disease may be due to the immature development of the hip joint in children, and the ligaments and joint capsule are relatively loose. When the lower limbs are excessively abducted and retracted, the gap between the femoral head and the acetabulum widens, and the negative pressure in the joint cavity entraps the synovial membrane or ligaments. Clinical symptoms and signs Pain in the hip joint, restricted movement, pain in the hip or knee joint of varying degrees, which may be accompanied by or first appear as pain in the ipsilateral inner thigh and knee joint, with the affected limb mostly in the abduction, external rotation and flexion position. In mild cases, painful claudication occurs, and in severe cases, the patient is unable to stand and bear weight. Infants and young children sometimes exhibit restlessness and crying at night, and the crying becomes more pronounced when the affected limb is moved passively. The child’s pelvis is tilted to the affected side when standing, the affected limb does not want to stand with weight, and is in the flexed hip and knee abduction and external rotation position, the Aills sign is positive, the Thomas sign is positive, the “4” test is positive, the relative length of both lower limbs is unequal, the pseudo-lengthening of the affected limb is within 2 cm, there is sometimes pressure pain in the groin on the anterior side of the affected hip joint, and there is mild swelling. Mild swelling, resistance to hip flexion, inversion, rotation, etc., and sometimes mild fullness of the inner side of the affected hip joint. The movement of the affected hip joint is limited, and the limitation of internal rotation is obvious. In severe cases, the hip flexion contracture test is positive, and the affected limb is placed in the abduction and external rotation position. Body temperature is normal or slightly elevated. Because the nerves in the hip joint are from the sciatic nerve and the anterior branch of the foramen ovale nerve, and the latter has a sensory nerve distributed in the knee joint, many children are often misdiagnosed as knee disorders because of knee pain. Due to their active nature, some children with post-injury lameness are not yet very obvious and still insist on activity, which is easily overlooked. This disease can continue to develop into ischemic necrosis of the femoral head, so early diagnosis and treatment is very important. According to clinical data, 2% to 10% of such patients may develop ischemic necrosis of the femoral head within two years after the onset of the disease, showing that hip synovitis seems to have some intrinsic connection with ischemic necrosis of the femoral head, and some scholars believe that temporary hip synovitis may be the early manifestation of osteochondritis of the femoral head (ischemic necrosis of the femoral head). If thorough treatment is carried out at an early stage, the progression to ischemic necrosis of the femoral head can be stopped. In other words, the progression of osteochondritis of the femoral head (ischemic necrosis of the femoral head) can be stopped in some patients who have temporary manifestations of synovitis of the hip joint and who actually have early osteochondritis of the femoral head. This disease should be diagnostically differentiated from synovial tuberculosis, femoral head necrosis, septic hip osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis. During the treatment period, activities such as jumping and running should be minimized in affected children, and bed rest is preferable, otherwise recurrent attacks will occur.