Painful venous malformations, generally referred to as venous malformations within the soft tissues of the body with varying degrees of pain, are mostly found within the muscles or around the joints, and are more common in the extremities. Due to the pain, it often affects the function of the limbs, often causing local dysfunction and even disability, these venous malformations are the most serious harm, and the priority in treatment is to solve the patient’s pain problem. Early stage, mild: easy fatigue, local muscle soreness and swelling, or pain when the joint moves. Mid-stage, moderate: swelling and pain after exercise, restricted activity, painful intermittent limping when the lesion is located in the lower extremity, or painful joint extension is obvious. Late, severe: persistent more severe pain, seriously affecting the daily life, some lesions in the lower extremities of patients can not even land on the heel. Some of the lesions are painful when the skin is touched. [Postural test] The lesion is observed by elevating or dropping the limb to cause a postural change in local limb blood pressure. The postural test is often significantly positive in patients with bruised lumps on the skin surface. [Limb circumference measurement] The difference in limb circumference should be less than 1 cm in normal individuals. For patients with painful venous malformations, the limbs may be thick and fat due to local swelling and skeletal abnormalities, or they may be thin due to disuse atrophy caused by pain. [According to 97 samples of painful venous malformations (51 males and 46 females, mean age 15 years) treated in our department from January 2006 to January 2008, the lesions were found in the limbs, most of which were located in the lower limbs, 66 cases (68%), and their specific sites included the iliac region, buttocks, arms, palms, fingertips, legs, knees, soles, etc. MRI is an ancillary test – the lesion is nowhere to be seen. Since the naked eye cannot determine the exact location and depth of the lesion and the relationship with the surrounding important tissues, MRI should be performed in all cases. Routine parameter selection includes SE or FSE sequence T1-weighted + fat suppression, IR and GE sequence T2-weighted in axial, sagittal and coronal positions. The lesion structure, size, and extent of infiltration involving the surrounding anatomical structures of the malformed vessels were observed. The specific locations of the lesions in the soft tissues were classified according to the MRI reflections: muscle; muscle interstitial; and joint. The lesions located in the intermuscular space are more likely to be painful, followed by intramuscular lesions. The mechanism of pain in painful venous malformation is still unclear, but we found that there are thicker and stiffer dermal nerve releases on the side of the lesion during surgery, and some patients have thickened and stiffened local fascia. It is thought that the cause of pain may be related to the abnormal local cortical nerve distribution. It has also been found that thrombosis and pain correspond to each other in some cases, while inflammatory reaction and pain correspond to each other in other cases, and no specific pathological manifestations were observed in some other cases, suggesting that the presence of thrombosis and local inflammatory reaction in the tumor may be related to pain. Other pain-related theories are: 1) stasis of blood flow, resulting in mechanical stimulation of the vessel wall and compression of the surrounding tissues due to increased intravascular pressure; 2) ischemia of the surrounding tissues, especially nerves, due to obstruction of blood return; pain caused by metabolic products of cellular tissue hypoxia; 3) intravenous thrombosis, which itself can directly and indirectly release some pain-inducing mediators. In a word, it can be attributed to factors such as abnormal local venous filling and expansion, extrusion, abnormal local nerve innervation, and abundant pain mediators. [Pain is the main concomitant symptom, some patients have mild soreness, pain or pressure, while a large proportion of patients have spontaneous pain or severe pain after activity, which directly or indirectly leads to functional impairment. Therefore, for the treatment of painful venous malformations, relief of pain and reduction of functional impairment is one of the important indicators of the efficacy of the treatment of body surface venous malformations. Since the lesions are located in the interstitial and intramuscular spaces, the commonly used methods of surgical palliative resection are prone to recurrence, while complete resection is highly traumatic, bleeding, and prone to serious local secondary deformities and dysfunctions, and the residual tumor is often found to have painful symptoms that cannot be completely resolved after surgery. The ideal treatment for painful venous malformation should have reliable pain relief, less trauma, good morphological and functional recovery, high safety and less recurrence. [Pain relief evaluation criteria] The effect of treatment can be divided into 3 levels according to the degree of pain relief based on the patient’s subjective evaluation of pain and referring to Jadad’s Pain Relief Scale.