A Case of Easily Misdiagnosed Intramuscular Hemangioma

Background: Intramuscular hemangioma is a kind of benign vascular tumors often occurs in the lower extremity, which occurs in the gluteus medius muscle, and was misdiagnosed as lumbar disc herniation is rarely reported. Case presentation: A female who complaint of of buttock. She was diagnosed The but will Until she a in which was suspected of malignant tumor. Then the tumor was resected and the nal diagnosis is intramuscular hemangioma. The symptoms disappear completely and not recurrent. Conclusion: There are usually no special symptoms in patients with intramuscular hemangioma, so it is often misdiagnosed, when the treatment is the should be timely and correctly analyzed.


Background
Hemangioma is a kind of tumor that originated from vascular tissue which occurs in cutaneous tissue, subcutaneous tissue, intramuscular, splanchnic tissue and osseous, almost every part of the body. The intramuscular hemangioma represents less than 0.8% of all hemangiomas [1] . But it is the most common type of deep intramuscular tumors [2,3] which is more common in people younger than age of 30. The intramuscular hemangioma in the body is usually asymptomatic at the initial stage. Only when the tumor is enlarged, it may compress and push the adjacent muscles and nerves, resulting in various symptoms.
Clinical lesions can involve any part of skeletal muscle, but the lower limbs are common. The larger the intramuscular hemangioma, the more di cult the treatment. For the early symptoms of the intramuscular hemangioma are not obvious, and have no speci city, it's di cult to early observe and make a clear diagnosis and often misdiagnosed. We present a case of a patient with an accidental pain of the left buttock with radiation pain of the back of the thigh. She was diagnosed as lumbar disc herniation, and accept long term treatment. But the symptoms still exist, and recur frequently.

Case Presentation
A 36-year-old female who complaint of accidental pain of the left buttock with radiation pain of the back of the thigh for ve years. She used to be a saleswoman and now mild obesity. Five years ago, she feels pain of the left buttock. The symptom happens about 6 to 8 times every year, which can be endured.
1 year earlier she seeks medical advice, no abnormality appearance found in physical examination of the spine and left hip, the ROM of the spine and the hip is normal, straight-leg raising test is suspicious, the gait is normal. Consider the above, the doctor suggest that she reduce daily movement, have a rest, lie down and take some physiotherapy, include traction, magnetic thermotherapy and wear waistline. Every time after take these treatments, the symptoms will slightly relieved soon, but when she go back to work, especially walk or stand for a long time, the symptom will relapse. Then as long as she takes the previously mentioned physiotherapy and some medicine, the symptoms will be better but not disappeared. Until 6 month ago, she was referred to an orthopaedic surgeon, who requested a X-ray( gure a) and magnetic resonance image( gure b,c,d) of the pelvis, which demonstrate that the density of the left ilium is not uniform, the edge is fuzzy, and high density shadows in the soft tissue, lumpy mixed abnormal signal in the gluteus medius and gluteus minimus muscles with unclear boundary with bone destruction of ilium, which is similar to the imaging features of malignant tumor, the SPECT also suspect that it is the bone metastasis of malignant tumor. After embolization of tumor main blood supply, the surgical intervention-the debulking surgery was conducted. The operation was performed under general anesthesia, in the lateral position, use the incision on the surface of tumor. The tumor is in gluteus medius muscle and very large with calci ed lesions. After carefully separate and exposure, we can see the the gross appearance of the tumor, then the tumor was removed thoroughly (Fig. 2). We can see the degeneration and atrophy of gluteus medius muscle due to the compression and erosion of the tumor.
During the surgery, the amount of blood loss is very small than preoperative prediction. There are no postoperative complications and no weakness in the gluteus. The immunohistochemical results of pathological sections prove that the specimen is intramuscular hemangioma with no evidence of malignant tumor. After operation the patient was referred to rehabilitation exercise and gradually return to work. For the rst week, she was allowed only isometric contraction of lower limb muscles everyday without hip movement, the next week, she was encouraged to move the hip, rst passive then active, rst exion then abduction, plus aquatic therapy, thus gradually recover the muscle strength. Now about 11 months after operation, the manual muscle testing scale of the gluteus medius muscle is level 5, she has resumed normal work and exercise level with no symptoms recur.

Discussion And Conclusions
Intramuscular hemangioma is a kind of benign vascular tumors, neoplastic proliferations of blood vessels that often occurs in skeletal muscle. It is characterized by the proliferation of endothelial cells, originated from the vascular tissue of mesoderm, and can be added to the lesions after trauma with in ltrative growth, invasive growth, no obvious envelope and boundary. The cause remains uncertain, both congenital and posttraumatic theories are considered in origin [4] . Traumatic and hormonal in uences have been suggested and may contribute to the aetiology or growth spurts [5,6] . Most of the intramuscular hemangioma is accompanied by mature adipocyte tissues of different numbers, also known as intramuscular angiolipoma. In some cases, chronic anoxia of myocytes and accumulation of metabolites may occur due to poor local blood circulation, which may be manifested as muscle swelling, pain, or even in ltrative scleroma, involving the whole muscle, brosis, calci cation, ossi cation and other bone damage. There are usually no special symptoms in patients with intramuscular hemangioma on the early stage, maybe no mass, no pain, no swelling. In the later stage, myosclerosis, contracture, muscle and joint deformities and dysfunction may occur. The most common symptom of intramuscular hemangioma is a slowly enlarging mass usually not associated with cutaneous changes, and pain without any bruit, pulsation, or thrill [7] , especially after exercise, just like the patient. Because of its deep location, variable size and shape, lack of speci city of clinical symptoms, and its biological characteristics are not obvious, the intramuscular hemangioma's preoperative diagnostic rate is only 8-19% [8] . So it is easy to be misdiagnosed clinically, and needs to be differentiated from soft tissue malignant tumors and others. The case is just demonstrates such typical symptoms and be misdiagnosed rst. Once she work or exercise, she feel pain of the left buttock, with radiation pain of the back of the thigh which is very similar to lumbar disc herniation. It may be related to the compression of sciatic nerve by the tumor. Furthermore the patient is mild obesity and her job needs to rush around. So she was diagnosed as lumbar disc herniation, which delayed the diagnosis and treatment to some extent. For intramuscular hemangioma, X-ray and MRI are often used in clinical diagnosis. On the X-ray lm, soft tissue block shadow or reticular density increased shadow can be seen, and about half of them can be seen vein stone shadow. MRI can give more diagnostic clues, on T1WI the tumor showed mixed shadow with equal or slightly high signal, while T2WI showed mixed shadow with high signal. The patient's X-ray demonstrates the nonuniform density of the left ilium with large calci ed lesions in the gluteus medius muscle. The MRI shows high density shadows in the soft tissue, lumpy mixed abnormal signal in the gluteus medius and gluteus minimus muscles with unclear boundary. All these clues cannot give us a clear diagnosis, furthermore the SPECT suspect it as malignant tumor. So we perform the angiography, and nd the main blood supply. Generally before the resection of tumor, if there is a de nite bruit and following arteriography identi es the feeding vessels, embolization of the vessels followed by meticulous extirpation of the tumor is recommended. For embolization decreases the profuse bleeding and shrinks the tumor allowing for safer and complete resection. Resection should follow embolization within hours, for collaterals reestablish themselves rapidly. So we embolize the main blood supply of the tumor during the angiography in order to contral the bleeding and safty of surgery.
Many literature have reported intramuscular hemangioma occur in various sites within the muscles of the trunk and the upper and lower limbs with predominance in the thigh muscles [9][10][11] . About 45% of the intramuscular hemangioma are found in the lower extremity, 27% in the upper extremity, and the remaining are equally distributed between the head and neck area and the the trunk. Because they are rare types of vascular tumors and are not usually suspected from clincal ndings, they are of interest to surgeons as a cause of diagnostic problems [12] . In this case, the intramuscular hemangioma occurs in the gluteus medius muscle, and demonstrate the similar symptom of lumbar disc herniation. It's very rare and easy to misdiagnose. For the intramuscular hemangioma often lack of speci c symptoms, mild, sometimes good or bad, no alertness. It should be noted that when the treatment effect is not satis ed, the cause may not be timely and correctly analyzed, which should complete further inspection.