Objetive Stress fracture is often misdiagnosed because of some misunderstandings. Our study is to explore the value of imaging in diagnosing the stress fracture. Methods We analyzed 64 cases of stress fracture,of which 27 were male and 37 were female. Plain X ray examinations were performed for all of them, and the ECT, MRI, CT examinations followed in 28 cases. Results We divided the stress fracture into fatigue fracture and insufficiency fracture. In our study, 12 cases were of the fatigue fracture, 18.7%in all cases; and the other 52 cases were of the insufficiency fracture, 81.3%in all cases. 36 cases were diagnosed by the plain films only, and other 28 cases by a combination of ECT, MRI, CT imaging. The fatigue fracture was dominantly seen in the tibia of the adolescent, while the thoracic and lumber spines of old female were the common area of the insufficiency fracture. Conclusion Generally the stress fracture can be diagnosed according to the clinical appearance and X ray plain film. But the ECT, and MR imaging are also necessary in diagnosing difficult cases and the fracture at its early stage.

Objective Lateral dislocation of the patella pulled laterally from the trochlea and across the lateral femoral condyle,was often a transient phenomenon with spontaneous reduction,diagnosis based on the results of physical examination and clinical history was difficult.The present was in an effort to explore the mechanism and definition of acute patellofemoral dislocation as well as assessment with MRI of the injury.Methods From May2001to July2002,34patients aging from11to25years with18males and16females,had a history of knee joint,28of which were experienced a twisting injury with the knee in flexion and internal rotation of femur on a fixed foot.Sagital,coronal and transverse MRI were performed with T 1 WI,T 2 WI,STIR and TSHIRT sequences.The manifestations of MRI were analyzed retrospectively,and clinical data,X-ray films,CT scan and the findings of arthroscopy were studied as well.Results All of34cases injured were found the signal intensity abnormalities of subchondral bone in the inferior medial part of patella and the anteri-or lateral part of lateral femoral condyle,which suggested that bone was injured.MRI findings of cartilage fis-sure at medial patella were found in20cases and injury of the patella retinaculum was seen at MRI in27cas-es.MRI findings revealed joint effusion in all patients,and lateral subluxation of the patella was seen at MRI in23cases.Conclusion The resultant jury on MRI findings of acute patellofemoral joint dislocation caused by a-cute impingent of patellar medial facet to lateral femoral chondyle at the various degree of flexion and rotation of the knee include the osteochondral fracture in the inferior medial part of patella,the anterior lateral part of lateral femoral condyle,the subluxation or dislocation of patella,the injury of medial patella retinaculum and the joint effusion.MRI could be helpful for the diagnosis of the disease,and demonstrate the location and ex-tent of injury on the different compartments of the involved knee.

Objective To explore the diagnostic value of MRI in tumor of soft tissue. Methods The MRI manifestations of 180 soft tissue tumors dating from October 2001 to August 2004 were retrospectively analyzed, they were all confirmed by pathology. All cases were examined with Picker 0.23 T MRI. Fast spin echo(FSE)T1 and T2-weighted sequences and short tau inversion recovery (STIR/TSHIRT) fat-suppressed sequences were commonly used. MR examinations were performed at least in two of coronal, sagittal, axial planes. Of 180 cases, there were 62 vascular tumors, 34 giant cell tumor of tendon sheath, 26 neural tumors, 23 lipomas, 18 fibrous tumors; 17 malignant tumors including 7 of malignant fibrous histiocytoma(MFH), 3 of malignant lymphomas, 2 of liposarcoma and one each of chondrosarcoma, myofibrosarcoma, melanoma, facial sarcoma and leiomyosarcaoma. 10 cases were of tumor-like lesions, including 2 of myositis ossificans, 8 of fat necrosis. GCT of tendon sheath (33/34 cases), hemangiomas (23/52 cases) were common in hands and feet. MFH often involved legs and upper arms(4/7 cases, 3/7 cases). The tumors in the groin were mainly malignant(4/5 cases). Results The ratio of benign to malignant tumors was 9∶1. Tumors showed isointensity or hypointensity in T1WI and hyperintensity or mainly hyperintensity but mixed signal in T2WI. The diameter of benign tumors was 1-18 cm, the malignant was 4-10 cm. The tumors were lobulated, oblong or irregular in shape. 12 invaded to bone, 28 involved to neurovascular system. Some body parts were easily involved because of different histologic component. Conclusion The MRI for soft tissue tumors is highly sensitive. The location and some characteristical signs are useful for diagnosis, whereas the size of the lesion, the degree of border smoothness and the signal intensity are not certain for the diagnosis.

Objective To explore the clinical value of helical CT surface shaded display (SSD) and multiplanar reconstruction (MPR) images in diagnosing the acetabular fractures. Methods According to the anatomical basis of "Y" type cartilage in children acetabulum, adult acetabulum was divided into "two columns" the anterior and posterior column and "four walls"the anterior, posterior, medial and roof walls, so as to define the localization, type, interface and union of fractures accurately. Results From 1999 to 2001, 68 cases of acetabluar fractures were reviewed. Of 68 cases, 28 cases were diagnosed as complex double columns and three walls (anterior, posterior and interior wall respectively) fracture, 7 cases as complex single column (anterior column) and three walls (anterior, posterior and interior wall) fracture, 5 as complex single column (anterior column) and two walls (anterior and interior wall) fracture, 21 as simple posterior wall fracture, 7 as simple anterior wall. In this group, 21 complex double columns and three walls fractures, 7 complex single column and three walls fractures, 5 complex single column and two walls fractures, 15 simple posterior wall fractures, 3 simple anterior wall fractures had reduction and internal fixed with plates or absorbable screws; another 7 complex double columns and three walls fractures, 6 simple posterior wall fractures, 4 simple anterior wall fractures were treated with traction reduction because the separation and displacement of their fragments were not significant. Using ?2 statistical analysis,there was a significant difference between the X-ray film and SSD and MPR in demonstrating the numbers and types. Conclusion SSD and MPR reconstruction imagines are of instructive importance in sufficient evaluation, operative preparation and appropriate instrumentation of internal fixation. In the management of acbtabular fracture, plates are needed to stabilize the fracture involved the anterior or posterior column, while the fragments of anterior or posterior wall are only fixed with screws, small fragments could be removed in order to avoid forming loose body. Therefore, SSD and MPR are the regular and important method in preoperative examination of complex acetabular fracture and dislocation.

Objective To evaluate the value of surface shaded reconstruction (SSD) of CT scanning on developmental dysplasia of the hip (DDH). Methods Unilateral DDH in 39 cases was examined with Picker 2000S spiral CT to perform SSD of the affected pelvis. All patients were females with the age ranging from 3.5 to 8 years old (average 4.25 years). Of 39 cases, 22 cases were complete dislocation the hip, 17 cases were subluxation of the hip. The measurement on SSD included of the depth and surface area of normal and affected acetabulum; the distances from the lowest point of the bottom of the acetabulum (O point) to the anterior end (A point) of the lateral margin of anterior acetabular column (OA), the middle point (B point) of the acetabular roof (OB) and the posterior end (C point) of lateral margin of the posterior acetabular column (OC). Results In normal hip, the medial and lateral margin of the acetabular roof was overlapping, and in DDH, a bony defect was found in the lateral acetabular margin in three-dimensional CT scanning. The depth of the dysplastic hip with subluxation and the normal hip was (21.25?1.25)mm and (23.89?1.56)mm respectively with significant difference(P

Objective To summarize the experience of early management in elderly patients with serious burning in order to raise cure rate. Methods Elderly patients (63 cases) with serious burning (burned area exceeding 30% or Ⅲ? area exceeding 10% ) admitted from 1990 to 2002 were retrospectively studied. Patients were divided into two groups according to the admission date, before and after January 1, 1996 since new management was extensively applied after 1996. These measures consisted of rapid and adequate fluid resuscitation, early enteral feeding and autograft after eschar excision. Results The incidence of sepsis and MODS was 38.7% and 19.4% respectively after 1996. It was evidently lower than the group before 1996(65.6% vs 43.8%, P

Objective To research the variety and the imaging features of bone tumor and tumor-like lesions in the talus.Methods The imaging features of 33 cases of tumor and tumor-like lesions in the talus were reviewed retrospectively.All cases were confirmed by operation and pathology,All of 33 cases were performed X-ray examination,23 cases were examined by CT,and 11 cases were taken by MR.Results In 33 cases,24 cases were males,9 cases were females; including 7 cases of chondroblastoma(21.2％),7 cases of giant cell tumor(21.2％)(1 case of recurrence),6 cases of osteochondroma(18.2％),2 cases of osteoid osteoma(6.1％),7 cases of adjacent joint bone cyst(21.2％,2 cases of fibrous dysplasia of bone(6.1％),1 case of bone cyst(3％),1 case of malignant fibrous histiocytoma(MFH) of bone(3％).6 cases showed pathological fractures.The X-ray and CT imaging features of chondroblastoma,giant cell tumor,adjacent joint bone cyst,fibrous dysplasia of bone,bone cyst demonstrated cystic bony destruction.The common location of chondroblastoma were the posterior of talus(57％),expanding growth slightly,margin were mild osteosclerosis.The margin were osteosclerosis irregularly and osteal ridges showed in giant cell tumor.MRI features were different on pathologic basis,isointense and hypointense signal on T1WI and hyperintense signal on T2WI usually.The osteochondroma showed osseous protuberance connecting the talus,some cases showed calcification in the cap.The imaging of MFH in the talus X-ray and CT showed ill-defined osteolytic bony destruction,soft tissue-mass,no periosteal reactions and bone formation.MRI showed isointense and hypointense signal on T1WI and isointense and hyperintense signal on T2WI.The extent of tumour invasion clearly displayed.Conclusion Tumor and tumor-like lesion in the talus were rare.But there are great varieties.The benign tumor was more common than malignant tumor.Chondroblastoma,giant cell tumor,osteochondroma,osteoid osteoma and adjacent joint bone cyst were relatively common and had some imaging features.Malignant tumor rarely happened in the talus,but it is possible.

Objective To investigate causes and effects of medial meniscus extrusion in patients with knee osteoarthritis.Methods A total of 120 patients diagnosed as knee osteoarthritis between January 2011 and March 2012 were enrolled in this study,including 60 patients with medial meniscal extrusion confirmed by MRI (extrusion group) and other 60 patients without medial meniscal extrusion (control group).The extrusion distance of medial meniscus and tibiofemoral angle were measured on MRI.The correlation between tibiofemoral angle and extrusion distance were analyzed.The incidences of genu varum,medial meniscus injury and cartilage lesion of medial tibiofemoral joint were compared between two groups.The effect of medial meniscal extrusion on meniscus injury and effect of genu varum on meniscal extrusion were analyzed.Results In extrusion group,the extrusion distances of medial menisci ranged from 3.76 to 11.6 mm (average,8.3±1.79 mm); all patients had genu varum,and the tibiofemoral angle ranged from 174°to 181°(average,179.0°±2.2°); the incidence of medial meniscus injury was 50.0％ (30/60) in the anterior horn,93.3％ (56/60) in the body,and 93.3％ (56/60) in the posterior horn; the incidence of medial meniscus tear in the root of the posterior horn was 23.3％ (14/60); the incidences of cartilage degeneration in medial tibial plateau and medial femoral condyle both were 100％ (60/60); a significant negative correlation was observed between dimension of tibiofemoral angle and extrusion distance of medial meniscus.In control group,the extrusion distances of medial menisci ranged from 0 to 2.61 mm (average,0.57±0.80 mm); four patients had genu varum,and the tibiofemoral angle in all patients was 180°; the incidence of medial meniscus injury was 0 in the anterior horn,16.7％ (10/60) in the body,and 70.0％ (42/60) in the posterior horn; no medial meniscus tear was found in the root of the posterior horn; the incidence of cartilage degeneration was 26.7％(16/60) in medial tibial plateau and 30.0％ (18/60) in medial femoral condyle.The odd ratio of meniscus injury and the number of genu varum (extrusion group/control group) was 6.0 and 15.0,respectively.Compared with the control group,the incidences and severities of medial meniscus injury and cartilage lesion of medial tibiofemoral joint were higher in extrusion group.Conclusion Genu varum may be one cause of medial meniscal extrusion.Medial meniscal extrusion increases incidence of medial meniscus injury and has a significant influence on generation and development of osteoarthritis in medial tibiofemoral joint.

Objective To evaluate the clinical effectiveness of the treatment for hip osteoid osteoma by CT-guided percutaneous microwave ablation. Methods From August 2006 to January 2010, 8 patients with the osteoid osteomas of the hip were treated with CT-guided percutaneous microwave ablation, including 5 males and 3 females with an average age of 18.8 years (range, 12 to 25). The history of local pain was ranging from 2 months to 10 years, with aggravation of pain at night. The locations of the lesions contained: 4cases in the neck of femur, 2 in the lesser trochanter, 1 in the greater trochanter and 1 in the femoral intertrochanteric line. After localization of the nidus with CT, osseous access was established with a Gallini puncturatio needle. After scanning the nidus with CT, a trocar was used to obtain specimens for pathological examination. Subsequently, a microwave probe was introduced through the biopsy needle to the nidus. Microwave ablation was performed at 90 ℃ for 4 to 6 minutes. Prophylactic antibiotics were used two days postoperatively. Results Three patients were diagnosed as osteoid osteoma with the pathological confirmation after the operation, 5 cases were not diagnosed by the pathological confirmation. All the cases were followed up for 6 to 21 months. All the patients reported alleviated pain in the first 24 hours postoperation. One case with lesion in the right proximate femur retained mild pain without nonsteroidal antiinflammatory drugs 5 month after operation. The same procedure was done once more on this patient, and the outcome was good. No osteonecrosis of the femoral head and other complications were observed in all patients. Conclusion By CT-guided percutaneous microwave ablation for osteoid osteomas of hip reliably relieves pain with few complications and recurrences. The short-term efficacy is satisfactory. It is a safe and effective technique for treatment of osteoid osteoma.

Objective To evaluate the clinical value of a novel anvil insertion technique in intracorporeal esophagojejunostomy and esophagogastrostomy after laparoscopic total or proximal gastrectomy.Methods A total of 40 patients with gastric cancer underwent laparoscopy-assisted radical total or proximal gastrectomy with lymph node dissection,followed by esophagojejunostomy or esophagogastrostomy using a reverse anvil insertion technique (the observation group,n =22) or traditional open surgery technique (the control group,n =18).Data of the two groups were compared.Results In observation group,laparoscopic total gastrectomy and esophagojejunostomy were successfully performed in 17 patients,laparoscopic proximal gastrectomy and esophagogastrostomy were successfully performed in the 5 patients,and no conversion to open surgery occurred.The mean time of operation was (272.0 ±49.8)min,including (12.9 ±4.3)min for anvil insertion and (48.1 ± 12.8)min for digestive tract reconstruction,which were significantly shorter than those in control group (P ＜ 0.05).The mean time of getting out of bed in observation group was (3.4 ± 0.8) d,the mean time of post-surgical eating was (8.0 ± 2.6) d,and the mean time of hospitalization was (10.8 ±3.3)d,which were all similar with those from the control group (P ＞0.05).Conclusion The reverse anvil insertion technique is a reliable strategy for laparoscopic esophagojejunostomy or esophagogastrostomy.