Objective: The incidence of acute spinal cord injury in children has increased in recent years, dance, traffic accident and trauma are the causes of acute spinal cord injury. The clinical manifestations of spinal cord injury in children are various. Abnormal urination is one of the main manifestations of low spinal cord injury. This study is mainly aimed at the bladder function after low spinal cord injury in children. To analyze the characteristics of bladder function changes after acute spinal cord injury in children, explore the effect of biofeedback therapy on bladder function recovery, and the best treatment plan.

Methods: 28 children with spinal cord injury caused by trauma were retrospectively analyzed. They were all low spinal cord injuries, 6 to 12 years old. There were 10 males and 18 females. Urodynamic examinations were performed within 2 weeks after injury, of which 16 cases received routine rehabilitation treatment, and 12 cases received pelvic floor muscle biofeedback electrical stimulation at the 4th week after injury. The daily urination frequency, daily average urination volume, residual urine volume, urinary dynamic index, quality of life score and international lower urinary tract symptom score were recorded in each group at 4 and 8 weeks after treatment.

Results: 22 cases (78.6%) showed no contraction of detrusor and increased bladder compliance, while 6 cases (21.4%) showed excessive detrusor activity and decreased bladder compliance. The indexes of the two groups were recovered and improved in varying degrees after treatment (P < 0.05), and there was no significant change in bladder pressure (P > 0.05). The improvement of the combined biofeedback group was better than that of the control group (P < 0.05), especially at 8 weeks. The improvement of detrusor weakness was more obvious in the combined biofeedback group (P < 0.05).

Discussion: Among the 28 cases, 22 showed low bladder function, most of which were detrusor weakness, decreased bladder compliance, a few showed spastic bladder and decreased bladder compliance. The two showed different clinical manifestations, which may be related to the level and location of spinal cord injury. Further study is needed. After routine rehabilitation, the bladder function recovered to different degrees in 4 and 8 weeks after injury, which indicated that the spinal cord function itself had a repair process. According to the degree and time of injury, the recovery of bladder function was different. After combined biofeedback treatment, the recovery of bladder function at 4 and 8 weeks was significantly better than that of routine rehabilitation alone. The biofeedback of pelvic floor EMG stimulation plays an important role in the bladder function recovery. And with the prolongation of treatment time, the recovery of bladder function is more obvious, spinal cord recovery and bladder function improvement need to adhere to long-term treatment. Of course, biofeedback therapy is not suitable for any type of bladder dysfunction. It is more effective in children with detrusor weakness, which is related to stimulating muscle contraction and reducing bladder compliance.

Conclusion: Most neurogenic bladders caused by acute spinal cord injury are characterized by detrusor weakness and increased bladder compliance. A few manifestations were detrusor hyperactivity, decreased bladder compliance. The routine rehabilitation treatment can recover bladder function slowly with spinal cord repair. Early combined biofeedback electrical stimulation therapy can significantly improve clinical symptoms and quality of life, especially in children with detrusor weakness, the effect is more obvious, and is proportional to the treatment time. Therefore, it is necessary to perform urodynamic examination in time after acute spinal cord injury in children. To clarify the type of bladder dysfunction is conducive to the choice of further treatment options, and also provides a basis for biofeedback therapy.