Ⅴ型成骨不全的特殊临床表现及影像特点

Specific clinical and imaging features of osteogenesis imperfecta V

目的：分析Ⅴ型成骨不全的特殊临床表现及影像特点，提高对本病的诊断水平。方法回顾性分析经过影像及临床诊断为Ⅴ型成骨不全15例患者的临床和影像资料，其中男10例、女5例；年龄1.0～30.0岁，中位年龄12.5岁。所有患者均行X线检查，同时行CT检查者4例。所有资料均经3名具有多年成骨不全症治疗经验的副主任医师根据Ⅴ型成骨不全诊断标准进行分析整理。结果15例患者X线平片可见前臂骨间膜钙化，2例可见胫、腓骨骨间膜钙化，13例患者可见桡骨头脱位，其中双侧脱位9例、单侧脱位4例，并且伴随桡骨头脱位的往往有比较巨大的尺骨鹰嘴及冠状突。所有患者均有前臂旋转功能及肘关节屈伸活动受限。7例可见四肢长骨的巨大骨痂，其中股骨骨痂7例，同时伴有肱骨骨痂3例、胫骨骨痂1例。早期表现为骨痂皮质菲薄，骨痂同股骨干界限分明，骨痂内密度低，巨大椭圆骨痂轮廓内可见不规则网格状分层形成；后期表现巨大骨痂内密集钙化，密度同股骨干相差不明显，但股骨干界限仍可见，骨干皮质无破坏。CT表现：巨大椭圆骨痂轮廓内可见稀疏针点状钙化形成，呈颗粒状、弓环状或不规则分隔状钙化。股骨干近端横断面形态不规则，扁方样形状，股骨干髓腔细小，骨痂边缘无明显钙化。骨痂内部CT值为-91HU，股骨干CT值为283 HU。结论Ⅴ型成骨不全的特殊表现有尺、桡骨及胫、腓骨骨间膜钙化，巨大骨痂生成，桡骨头脱位，X线检查可基本明确。CT扫描有助于同骨肉瘤鉴别。

Objective To evaluate specific clinical and imaging features of osteogenesis imperfecta V and to improve diagnostic accuracy of this disease. Methods Data of 15 patients with osteogenesis imperfecta type V were retrospectively analyzed for their clinical and imaging features. There were 10 males and 5 females, aged from 1 year and 30 years old （median age,12.5 years ）. All 15 patients had plain X-ray, and 4 of 15 had CT. All data were analyzed by 3 experienced deputy chief doctors in OI according to OI V standard. Results X-ray：calcification of the interosseous membrane between radius-ulna was detected in all patients and calcification of the interosseous membrane between tibia-fibula was detected in 2 of 15 patients. Dislocation of the radial head was seen in 13 of 15 patients,bilateral in 9 and utilateral in 4.All patients showed restriction in the pronation and supination of the forearm and restricton in the flexion and extention of the elbow joint. Patients with dislocation of raidal head were associated with large coronoid process and olecranon of the ulna. Hyperplastic callus of the extremities were detected in 7 of 15 patients （7 at femur , 3 at humerus, 1 at tibia.In early stage, hyperplastic callus showed thin cortice, and clear boundares with the diaphysis showing and low density, irregular, mesh-like lamellation inside. In the later stage, there were dense calcification inside hyperplastic callus, and no difference in density with the diaphysis. Diaphysis surrounded by hyperplastic callus had clear boundaries with the hyperplastic callus. No cortical destruction was detected. CT：there were sparse needle-dot calcification inside hyperplastic callus, with the patterns of granular, ring-and-arch,irregular streaky mineralization. The cross section of proximal femoral shaft showed irregular shape , flat square shape and tiny medullary cavity, with no calcification on the edge of hyperplastic callus. CT value：-91 HU inside hyperplastic callus; 283 HU in femoral shaft. Conclusions Interosseous membrane between radius-ulna or tibia-fibula, hyperplastic callus ,dislocation of the radial head are specific features in osteogenesis imperfecta V. X-ray can make a definitive diagnosis of osteogenesis imperfecta V. CT scan is helpful in the differential diagnosis of osteogenesis imperfecta V from osteosarcoma.