In an aging society, back and leg pain is very common, affecting the daily life and travel of patients, and has become an important health problem, and lumbar disc herniation is the main cause of back and leg pain. However, some middle-aged and elderly friends found that after a variety of ways to treat lumbar disc herniation, lumbar and leg pain is still not improved, then we need to carefully find the cause. Ms. Yao is an accountant of a large state-owned enterprise, 49 years old, sitting in front of the computer office for a long time, 3 years ago, lumbosacral pain, thought it was poor sitting posture caused by lumbar muscle strain, medication and massage physiotherapy did not improve, and then the right lower limb pain, pain from the hip, thigh after the calf and plantar radiation, feeling “a tendon hanging firm”. Ms. Yao thought it might be a nerve problem and did not dare to take it seriously, so she went to the orthopedics and neurosurgery department of the local provincial medical school hospital and was diagnosed with lumbar 4-5 and lumbar 5-sacral 1 disc herniation. However, the symptoms were only partially relieved after the operation, and did not heal. Ms. Yao then paid special attention to life care, did not dare to bend, did not dare to sit, work was also affected to some extent. Since then, her condition has not stopped progressing, and on top of the original back and leg pain, she has developed internal anal swelling and stabbing pain, and the pain in the anal area is getting heavier and heavier after sitting for a long time, and gradually decreases after lying down. Walking was also greatly restricted, and I felt severe soreness in my lower limbs after walking 500 meters and was forced to stop and rest, thus seriously affecting my life, and I could not work normally, so I had to apply for a medical discharge. After carefully analyzing her preoperative and postoperative imaging data, Dr. Zheng Xuesheng, head of the neurosurgery lumbosacral team, arranged a special 3D-FIESTA magnetic resonance imaging for her, and found that although the compression of the nerve roots by the herniated lumbar disc had been completely lifted, there was a sacral cyst at the sacral 1-2 level, which formed a clear compression, which had to be resolved surgically. After adequate preoperative preparation, Ms. Yao underwent “endoscopic closed cyst neck blocking surgery”, after which her symptoms were completely relieved and there is no sign of recurrence to date. Sacral cysts are not uncommon and are often combined with lumbar disc herniation to complicate the condition. Sacral cysts are divided into two types: if the cyst is a simple dural diverticulum with no internal nerve roots, it will not cause symptoms and does not need surgery; on the contrary, if the cyst involves sacral nerve roots, it will cause lumbar regression pain, perineal pain and even urinary and fecal abnormalities and sexual dysfunction with the gradual enlargement of the cyst, which requires timely surgery. However, traditional sacral canal cyst excision is difficult and risky, especially it may cause recalcitrant cerebrospinal fluid leakage and non-healing wound, so it is not carried out in many hospitals. This technique does not require removal of the cyst wall, so it fundamentally reduces the complications of cerebrospinal fluid leakage surgery, greatly improves safety, and significantly improves the efficacy of surgery, with a recurrence rate of less than 10%. In addition, in addition to sacral cysts, conditions such as calcification of ligamentum flavum hyperplasia and spinal stenosis can also make lumbar disc herniation surgery ineffective, so it is particularly important to choose a reasonable imaging examination before surgery and not to miss details on image analysis.