To Investigate The Imaging Appearance Of Hereditary Multiple Exostoses And Analyse It's Complication

OBJECTTo investigate the imaging appearance of hereditary multiple exostoses(HME), and analyse the complication relating to the HME.METHODS182 patients with HME were included in this study. imaging studies were adopted in 147(81%,147/182) of the patients. Data including patient age, sex, hereditary history, tumor site and imaging features were registered and analyzed. Based on the ratio of diameter between tumor tip and its basis, the tumor were classified into two types fungating type (tumor tip/tumor base≥1.0) and non-fungating type (tumor tip/tumor base<1.0). In addition, non-fungating type tumors were further classified into two subtypes:sessile type(tumor height to its base≤1.0) and pedunculated type(tumor height to its base>1.0) according to the ratio of height to base of tumors.All data was processed by Statistical Package for the Social Sciences(SPSS) 13.0 software.The relationship among the tumor types, tumor calcification and its malignant transformation were analysed with Pearson chi test. The relation among exostotic chondrosarcoma, sex and patient age were analysed with the corrective formula of Pearson chi test. RESULTSOf the 182 patients (125 men and 57 women) with HME,120 patients were diagnosed HME before 12 years old (66.1%),and 156 patients were diagnosed HME before 18 years old (85.5%), the ratio of male to female was 2.19:1. Among these patients,36 patients were found with hereditary history of HME,80 patients with no definite hereditary history, and hereditary history were undefined in 66 patients. Of the 36 patients with definite hereditary history,20 (56%,20/36) were inherited from their fathers, and 16 (44%,16/36)from their mothers, respectively.78 (78.8%,78/99) femoral necks were shortening. Madelung-like deformity were found in 30 (66.7%,30/45) patients. Genu valgum were found in 6 (2.6%,6/288) patients. Deformity of tibia and fibula were 4 (7%,4/54) respectively, and ankle valgum were 5 (9.2%,5/54) patients.The classification of tumor was related to their anatomic sites:non-fungating type including sessile subtype and pedunculated subtype were the main appearance around knee joint. The non-fun gating type tumors occupied 1029(91.2%)of the tumors around the knee. However, tumors in fungating type were more happened in pelvis than in non-fungating type. There were 27 (81.8%) fungating type tumors were found in pelvises. Tumor in sessile type and fungating were the main types in femoral necks,Total 55 (91.7%) sessile type and fungating tumors were found at femoral necks.Of the 182 patients,15 exostotic chondrosarcomas were found in 15 patients (3 women and 12 men), and there was no significant difference (χ2=0.4846, P>0.05) between the patient sex and the malignant transformation of tumor. Of the 15 patients with exostotic chondrosarcomas, malignant transformation of tumor was found in 13 patients more than 18 years old, and in 2 patients younger than 18 years old, There is a significant difference (χ2=17.1427, p<0.05) between the malignant transformation of tumor and patients who were older or younger than 18 years old. Tumor calcification, thickened cartilage-cap, the soft tissue surrounding the tumor, and ring or arc enhancement after administration of intravenous contrast material were seen in 12 patients. Calcification of cartilage-cap was found with a significant difference (χ2= 210.8540, p<0.05) between tumors with fungating type and non-fungating type. Of the 15 "exostotic" chondrosarcomas,13 were fungating type, and 2 were sessile type. Malignant transformation of tumor was found with significant difference (χ2=38.0075, p<0.05) between fungating and non-fungating types. The other imaging features included 2 popliteal pseudoaneurysms,4 bursitis,2 compression of organs in pelvic cavity,1 compression of sciatic nerve, all the exostoses were fungating type, except 1 sessile type which produced bursitis.CONCLUSIONS1,HME had a predilection to be diagnosed in teen-agers. It was more happened in male than in female with a ratio of 2.19:1. HME inherited from their fathers was more than those inherited from their mothers.2,Shortening of femoral necks and Madelung-like deformity had higher morbidity than others deformity in HME,and the appearance of them suggested a diagnosis of HME.3,Non-fungating type (sessile type and pedunculated type) were the main type of the tumors around shoulder joint, wrist joint, knee joint, ankle joint and rib. And fungating type were more happened in pelvis than non-fungating type. Sessiletype and fungating were the main types of the tumors at femoral necks.4,The calcification of cartilage-cap and malignant transformation were more found in fungating type than in non-fungating types (p=0.000). Malignant transformation of the "exostotic"had no gender predilection (P>0.05). Tumor malignant transformation was higher in patients older than 18 than patientsyounger than 18 (p<0.05). Fungating type could produce popliteal pseudoaneurysms and bursitis, compress organs in pelvic cavity and sciatic nerve.