Objective To explore the clinical and MRI features of spontaneous osteonecrosis of the knee(SONK).Methods 15 patients with SONK diagnosed by clinic and imaging were collected.All of cases were examined by MRI,of them 5 cases underwent CT scan and 3 cases underwent radiographic examinations.Results The subchondral lesions were seen in all cases on MRI and the lesions located in the femoral condyle weight-bearing zone in 14 cases.The subchondral "fracture cleft"sign was found in 2 cases;the subchondral long T1 and short T2 linear abnormal signal intensity surrounding with bone marrow edema were shown by MRI in 3 cases of them.The subchondral focal lesions were slight long T1 and long T2 signal intensity in 10 cases.The subchondral lesion were showed clearly only in 2 cases of 5 cases with CT scan,and only 1 case of 3 cases with plain X-ray examinations.Conclusion MRI is more sensitive than CT and radiography in showing the lesions of SONK.The SONK can be diagnosed based on the clinical and MRI features.

Objective To explore scanning technique in 64-slice spiral CT angiography, and to evaluate the clinical value of various of post-processing methods.Methods 45 patients were examined with CT angiography, including 4 cases of thoracic aorta, 15 cases of abdominal aorta,10 cases of pulmonary artery, which delay time was determined by bolus tracking. The delay time of others ,including 4 cases of cerebrovascular, 6 cases of cervicum blood vessel and 6 cases of lower limb artery were determined by artifical. The initial images were processed with MPR, CPR, MIP ,SSD and VRT.Results According to standard valuation of imaging quality ,the good images were 37 cases, the better were 8 cases and none was bad.Conclusion As far as the diagnosis of great vessels is concerned, 64-slice spiral CTA can instead of DSA. MIP and VRT are important methods in post-processing of image.

Objective To investigate the imaging features of dysplasia epiphysealis hemimelica (DEH).Methods Thirteen cases of DEH confirmed by pathology (between 1.5 to 19.0 years old)underwent X-ray scan.Additionally,CT scan was performed in one patient,MR scan was performed in one,and CT and MR scan were both performed in one.Results The lesions all occurred in lower limb.There were 32 lesions,and multiple lesions were detected in 8 cases.Lesions involved holo-epiphyses in 6 cases,Twenty-three lesions were in the medial limbs,3 were in the lateral limb.With Azouz classification,the limited form was identified in 5 cases,while the classic form was identified in 8 cases.Among 13 cases,there were 4 cases with ankle eversion,3 cases with the knock knee,2 cases with the ankle inversion,and 2 cases with the strephexopodia.The metaphysis of 8 cases were widened and deformed,and the provisional zone of calcification of 1case disappeared partly and the epiphysis closed prematurely.Conclusions One or multiple eccentric enlarged ossification center of unilateral or bilateral limb is the imaging feature of DEH.There is sporadic calcification or ossification on the prophase.The calcification or ossification can fuse each other to form agglomerate at the advanced stage.The bone can deform and shift when compressed by the mass,and bone defect can even occur.

Objective To suty the MRI manifestations of juvenile acute articular cartilage injury of the knee joint.Methods MRI findings of cartilage,subcartilage low signal line and subcarilage bone were analysed retrospectively in 53 juvenile patients (ranged in age from 4~27 years) with acute articular cartilage injury confirmed by arthroscopy.Results Sixty-nine cartilage injuries were showed by MRI in 53 patients,including patellas in 25,femoral lateral condyles in 22,femoral medial condyles in 11,trochlea of the femur in 2,and tibial plateau in 9.Acute articular cartilage injury appeared as pure cartilage fracture in 46, including complete split of the cartilage in 22 sites,partly split of the cartilage in 20 sites,and fissur-like fracture in 4 sites.Osteochondral fracture were observed in 23 sites,including avulsion fracture in 13 and osteochondral subsided in 10.Articular cartilage loose bodies and osteochondral loose bodies were found by MRI in 6 and 13,respectively.Conclusion MRI is the best non-invasive method for studying cartilage injury.

Objective To analyze the X-ray,CT and MRI appearances of primary synovial osteochondromatosis.Methods CT scanning was performed in 22 cases,of which 16 cases underwent X-ray examination and 2 cases underwent MRI scan.Results Of 22 cases of synovial osteochondromatosis,13 cases were male and 9 cases were female.The monoarticular involvment was found in 20 cases,and double-articular involvment in 2 cases.Variable size and number of the cartilaginous nodules with calcification and ossification within and surround the joints were showed in 20 cases.The soft mass with calcification were showed in 2 cases.Bone destruction were found in 2 cases,which were induced by compression of the cartilaginous nodules,this was confirmed by operations.Conclusion The cartilaginous nodules with calcification or ossification can be shown by X-ray and CT san.The cartilaginous nodules without calcification or ossification can be shown by MR san.

Objective To analyze the pattern of normal bone marrow on whole body diffusionweighted imaging (WB-DWI) and its influence factors.MethodsA total of 98 healthy volunteers (male 47 and female 51). All volunteers underwent WB-DWI at 1.5 T MR scan. The ADC value,the signal intensity on DWI obtained with a b value of 800 s/mm2 ( SIDWI ),and the signal intensity on short time inversion recovery images ( SISTIR ) of thoracic vertebrae,lumber vertebrae,bilateral head of femur,bilateral neck of femur,bilateral superior segment of femur,bilateral inferior segment of femur,bilateral ilium,bilateral head of humerus,bilateral scapula were measured and compared with ANOVA test and StudentNewmar-Keuls test.The normal appearance of bone marrow on WB-DW[ was assessed. The relationship between the SIDwI and the ADC,and the SIDWI and the SISTIR of bone marrow were analyzed.The ADC of bone marrow between male and femaIe were compared. Spearman correlation analysis was performed for different age groups.Results( 1 ) Bone marrow signal intensity was different among 98 healthy volunteers.Bone marrow in 69 healthy volunteers (female 24,male 45 ) showed low to intermediate signal intensity,whereas in the remaining 29 healthy volunteers (female 27,male 2) showed high signal intensity.(2) The SIDWI of thoracic vertebrae ( median 44.54),lumber vertebrae ( median 35.01 ),head of femur ( median 13.61 ),neck of femur ( median 16.00),superior segment of femur ( median 21.45 ),ilium ( median 25.77),head of humerus (median 18.35),scapula (median 36.12) was positively correlated with the ADC [ (0.55 ±0.08) × l0-3,(0.53 ±0.08) × 10-3,(0.30 ± 0.10) × 10-3,(0.42 ± 0.16) × 10-3,(0.74±0.14) ×l0- 3,(0.49±0.10) ×10-3,(0.36±0.13) ×10-3,(0.49±0.11) × 10-3mm2/s]and the SISTIR ( median 61.81,64.99,53.27,69.08,73.10,66.35,73.16,79.81 ),r =0.513 and 0.695,0.741 and 0.764,0.443 and 0.489,0.641 and 0.656,0.510 and 0.648,0.475 and 0.715,0.366 and 0.446,0.437 and 0.739 ;P ＜ 0.01. (3) There was significant difference of the ADC of bone marrow in different bone,F =138.69,P ＜ 0.01. Student-Newman-Keuls test revealed that no significant difference was found in the ADC between thoracic vertebrae and lumbar vertebrae,ilium and scapula,head of humerus and inferior segment of femur ( P ＞ 0.05 ),and significant difference was found in the ADC values between the remaining two groups ( P ＜ 0.05 ). The bones associated with decreasing ADC values were superior segment of femur,thoracic vertebrae and lumber vertebrae,ilium and scapula,neck of femur,head of humerus,head of femur and inferior segment of femur. ( 4 ) The ADC values of bone marrow of female subjects in thoracic vertebrae [ (0.59 ±0.07) × 10-3 mm2/s],lumber vertebrae [ (0.58 ±0.06) × 10 -3 mm2/s],head of femur ( median 0.33 × 10 -3 mm2/s),neck of femur ( median 0.53 × 10 -3 mm2/s),superior segment of femur ( median 0.81 × 10-3 mm2/s),inferior segment of femur ( median 0.32 ×10-3 mm2/s),ilium [ (0.52 ± 0.09 ) × 10-3 mm2/s ],head of humerus (median 0.42 × 10-3 mm2/s),scapula [ (0.53 ± 0.09) × 10-3 mm2/s] were significantly higher than those of male subjects [ (0.51 ±0.07) × 10-3,(0.48 ±0.07) × 10-3,median 0.23 × 10-3,median 0.31 × 10-3,median 0.66 × 10-3,median 0.23 × 10-3,(0.46 ±0.10) × 10-3,median 0.27 × 10-3,(0.45 ±0.11 ) × 10 3mm2/s].(5)There was significant negative correlation between the ADC values of bone marrow and age in thoracic vertebrae,lumber vertebrae,head of femur,neck of femur,superior segment of femur,ilium,head of humerus for female subjects,r =-0.549, -0.629, -0.329, -0.524, -0.338, -0.548 and -0.416,respectively,P ＜ 0.05.There was no significant correlation between ADC values and age in inferior segment of femur and scapula for female subjects and all the regions for male subjects ( P ＞ 0.05 ).Conclusions The ADC and the SIsTIR of bone marrow correlates with the SIDW1.The ADC values of bone marrow is affected by age and sex,and is different for different bones.

Objective To investigate the clinical efficiency of branch artery of the sural medial gastrocnemius muscle flap combine with sural nerve nutritional vessel axial.Methods From February 2006to March 2010,according to the position and size of the soft tissue defects,the muscle flap combined with branch artery of the sural medial gastrocnemius and sural nerve nutritional vessel axial were desingned and obtained to repair 7 cases of sofi tissue defects of the upper-region of the tibial.The flap size ranged from 8.0 cm × 8.0 cm to 12.0 cm × 10.0 cm.The vessel pedicle of branches ranged from 1.8-3.0 cm.The distribution of the vessel pedicle of branches ranged from 10.0-17.0 cm on the distant popliteal fossa,and ranged from 2.0-5.0 cm on the back of medial line.Results The outline and function were satisfactory during 6-15 months follow-up.Conclusion The blood supply of this flap is reliable without sacrifice of major arteries.Flap elevation is easy.It can transfer to a long distance and can repair large skin defects.It is very useful in repairing upper-region of the tibial large soft tissue defect.

Objective Because of high incidence rate of complicated postoperative abdominal infections in abdominal injuries and difficulty in their clinical diagnosis and treatment,this article aimed to investigate the mechanism and the surgical tactics for this kind of complication.Methods Totally 48 abdominal-injured cases of postoperative complicated abdominal infections in our hospital from July 2005 to December 2010 were reviewed.These patients (Male 30,Female 18) aged 16-70 (mean 38) years.There were 20 cases of simple abdominal injuries,and 28 cases of multiple injuries ( ISS 16 - 52,mean 24.42).The complicated postoperative abdominal infections included abdominal incision infections (25cases),intra-abdominal infections( 18 cases) and retroperitoneal infections(5 cases).Forty cases were transferrted from other hospitals to our hospital 2 - 76 days after trauma.16 of which underwent exploratory laparotomy at other hospitals after injury,and 8 cases were directly transferred to our hospital after injury.Results All patients finally had a definite diagnosis by abdominal checking(26 cases),paracentesis(5 cases),ultrasound and CT scan ( 12 cases),and PET/CT scan (5 cases)in our hospital,and were confirmed by cultiure of pathogenic bacteria.The treatment included vacuum sealing drainage (VSD) (25 cases),percutaneous imaging- guided abdominal abscess drainage(13cases) and re-laparotomy ( 10 cases).Successfull treatment was achieved in 46 patients,death in 2 patients.The causes of death consisted of 1 case of severe craniocerebral injury,1 case of MODS.Conclusions Complicated abdominal infections often occurs after the operations of abdominal injuries.attentively abdominal checking,paracentesis,and CT scan repeatedly were proofs to benefit the finally diagnosis.VSD therapy is a simple and effective method for abdominal incision complication,and dynamic CT scan and prompt exploratory laparotomy can improve patients' prognosis.

Objective To explore the imaing features of hemangioma in the long bone and improve the diagnostic level of this disease. Methods The X-ray(14 cases), CT(9 cases) and MRI(6 cases)findings of 18 patientswith histologically proven hemangioma in the long bone after surgery were retrospectively reviewed. Results Ten tumors occurred in medullary cavity or bone end(medullary type),6 on the surface of bone (periosteal type) and 3 in cortex (intracortical type). X-ray findings: among 8 cases of medullary type, 3 showed honeycomb appearance, 3 lytic areas with sclerotic borders, one purely osteolyticchanges, and 1 frosted glass; 3 cases of periosteal type showed sclerosis and thickening of the underlying cortex; 3 cases of intracortical type showed well-defined osteolytic foci. CT findings: among 6 cases of medullary type, 5 appeared as expansile lytic lesion with uneven selerotic rim (3 cases)orhoneycomb appearance (2 cases), 1 cribriform appearance in the cortical bone, 2 periostealnew bone formation in vertical radiation pattern; 1 ground-glass appearance; among 2 cases of periosteal typeone showed regular cortical thickening, and the other irregular periosteal proliferation with marrowing of medullarycavity; 1 case of intracorticaltype showed density similar to that of soft tissue, with cortical thickening and expansion . MRI findings: 2 apeared as well-defined lesions with low signal intensity on T1WI and high signal intensity on T2WI; 1 appeared as ill-defined lesion with low to intermediate signal intensity on T1 WI and T2 WI. One showed breakthrogh of cortex and formation of soft tissue mass with low signal intensity on T1 WI and high signal on T2WI. Two showed thickening of periosteumwith intermediate signal intensity in one of them and very low signal intensity in the other. Two showed abnormal signal intensity in surrounding muscles, which was high on T2 WI and intermediate on T1 WI. Conclusions The soap-bubble or honeycomb appearance is the typical radiographic finding of hemangioma in long bone. CT and MRI can provide useful information for the diagnosis of hemangioma in long bone.

Rectal diverticulum is rarely seen in clinical practice.Perforation or rupture of rectal diverticulum with symptoms and signs of acute diffuse peritonitis makes it easily be misdiagnosed as appendicitis,rectal neoplasms,intestinal obstruction and other abdominal diseases.In this article,a retrospective analysis of the clinical data of one patient with extraperitoneal pneumatosis caused by perforation of rectal diverticulum was performed to investigate the diagnosis and treatment of the disease.