Abstract: Patient Chen Xiaojun, sex male, age 6 years, diagnosis: left femoral stem fracture. Treatment hospital: Fuzhou Second Hospital (tertiary care). Treatment plan: surgical treatment (closed reduction elastic nail internal fixation). Treatment result: Postoperative X-ray showed good alignment of the fracture, and the hip herringbone brace was fixed; 1 month postoperative follow-up, X-ray showed good healing of the fracture, and the brace was removed and functional exercise was gradually started; 9 months postoperative follow-up, X-ray showed good healing of the fracture, no obvious complications, both lower limbs were equal in length, normal sports activities and exercise, and the internal fixation was removed. The child was admitted to our hospital as an emergency because of “pain and limitation of movement in the left thigh for 3 hours due to trauma in a car accident”. The left thigh was swollen and deformed, with no obvious local petechiae. The left lower limb was shorter than the opposite side by about 2 cm, with pressure pain in the left thigh and positive longitudinal buckling pain in the left lower limb. The rest of the limbs had normal activity, sensation and blood flow. The physiological curvature of the spine existed without deformity, and there was no pressure pain or percussion pain in the spinous process, and the movement was free. The following radiographs were performed in the emergency department. Consider the diagnosis: left femoral stem fracture. Until the early 1990s, most children with femoral stem fracture were still treated with hip herringbone cast fixation or plaster fixation after traction. In recent years, pediatric trauma orthopedic surgeons have tended to favor surgical intervention to facilitate early activity in children, reduce the psychological impact of long-term cast fixation, and accelerate functional recovery. In older children and adolescents, doctors also believe that shortening and angular deformity of the limb resulting from surgical intervention are less common than traction and cast fixation, and in the 1980s and early 1990s, treatment options evolved from traction and cast fixation to external fixation, standard plates, and adolescent-type expanded intramedullary pins. The general treatment guidelines for femoral stem fractures in children (Campbell Orthopaedic Surgery in Children Volume 13) are as follows. Despite decades of great success in France with the application of titanium elastic nailing, it was not until the mid-1990s that it became widely accepted. Since then, several studies have demonstrated that elastic nailing for the treatment of femoral stem fractures in children does have excellent performance and low risk, is easy to master in the short term and is safe and effective for the patient. Therefore, we also choose closed reduction elastic nailing for the treatment of Xiaojun Chen’s child. III. Considerations for treatment 1. Indications and contraindications: In most treatment centers, elastic nailing is currently the most common choice for treating femoral fractures in school-aged children. For children under 5 years of age with a single femoral stem fracture, early hip herringbone cast fixation remains the most common treatment option. In children with combined multiple trauma, the probability of applying elastic nailing increases. The elastic nail has also been successfully used in adolescents older than 11 years or weighing more than 50 kg, but a high rate of complications has been reported. Because the elastic nail does not provide as strong a fixation as an interlocking intramedullary pin or plate, it is better suited for stable fractures such as transverse or short oblique fractures. The elastic nail can treat long spiral and comminuted femoral fractures with an increased risk of limb shortening. Elastic nailing has been reported to have a higher rate of poor fracture healing in the treatment of proximal and distal femoral fractures, and is therefore most suitable for mid-segment fractures. 2. Complications and prevention The most common complication is soft tissue irritation at the point of needle entry, with an incidence of 7% to 33%. The incidence of this complication can be reduced by placing the tail of the needle flush with the distal femur and leaving the tail of the needle less than 1 cm outside the cortex. Some children develop knee effusion due to pin-tail agitation. Fracture malunion rarely occurs with the application of a flexible nail. Deformed fracture healing is also uncommon, but can occur in children with large weight (>50 kg) distal and proximal femur fractures or fractures of unstable length. Flexible nailing can be used successfully in larger or older children, but data suggest a higher incidence of deformity healing and limb shortening in this population. Therefore, the advantages and disadvantages of elastic nailing should be thoroughly discussed with the family before performing surgery on such children. For high-risk children and fractures, careful consideration should be given to the choice of treatment method, and the risks and complications of different treatment modalities should be informed truthfully to assist the patient’s family in making a decision. IV. Treatment results 1. Postoperative X-ray showed good alignment of the fracture, and the hip herringbone brace was fixed for treatment, and the X-ray is shown below. 2. 1 month postoperative follow-up, the X-ray showed that the fracture healed well, and the brace was removed and functional exercise was gradually started. 3. 8 months postoperative follow-up, X-ray showed good fracture healing, no obvious complications, both lower extremities were equal in length, normal sports activities and exercise, the internal fixation was removed, X-ray is shown below. Postoperative management: In the early postoperative period, in order to reduce knee movement and improve the comfort of the child, a brace is often worn, which does not protect the fracture end but stabilizes the knee joint, because quadriceps injury and reflex inhibition can lead to knee flexion contracture deformity. Partial weight-bearing exercises are started after the child shows early bone scabs on imaging. Healing usually takes 2 to 4 months. Early postoperative lameness is common and will return slowly to normal later in life, which should be communicated to the child’s parents in advance. After the fracture has healed, the internal fixation can be removed six months after surgery. VI. Insight Fracture of the femoral stem in children is a very common trauma and is mostly treated conservatively because of its own peculiarities. However, surgical treatment is sometimes chosen due to age, weight, fracture pattern and social factors. Surgical treatment should meet the following characteristics: it is less traumatic and has a clear therapeutic effect; it is expected to achieve a one-time cure. Considering the above, an appropriate treatment plan should be selected according to the different ages. The flexible nailing technique is currently the most common option for treating femoral stem fractures in school-aged children. Wearing a postoperative brace can improve the comfort and knee stability of the child. Parents need to be informed in advance that lameness is common in the weeks to months following surgery. After the fracture has healed, the elastic nail can be removed six months after surgery.