留學(xué)生實(shí)習(xí)片骨骼系統(tǒng)2

1、Musculoskeletal system part twoImaging of common diseases Infective diseases of bone bone tumors Common chronic diseases of jointsInfective diseases of boneOsteomyelitisDefinitionOsteomyelitis is an inflammation of the bone or bone marrow, usually caused by a bacterial infection. Staphylococcus aure

2、us is the most common bacterium. Patients often present with pain. Patients may have systemic symptoms such as fatigue and fever.Radiographic feature of acute osteomyelitisRadiographs performed early in the course of disease may show subtle swelling of the deep soft tissue or edematous subcutaneous

3、soft tissues, but radiographs are often normal in the first 7-10 days of infection. By 10-14 days, a focal area of bone opacity develops in the metaphysis. This progresses to lytic destruction with surrounding sclerotic margin and associated focal periosteal reaction. Osteomyelitis, which is an acut

4、e or chronic bone infection, can result from the bacteria that causes Septic Arthritis. pusRadiograph of a shoulder in a patient presenting with shoulder pain shows no abnormality (left). Another radiograph obtained 3 weeks later shows patchy destruction (right). Acute OsteomyelitisAcute osteomyelit

5、isThe x-ray of the distal tibia demonstrates periosteal elevation (left-image arrowhead) and osteolysis (right-image arrowhead) findings consistent with osteomyelitis. The x-ray shown is from a 13-year-old girl with pneumonia who developed patchy destruction of the glenoid capsule (arrowhead) due to

6、 osteomyelitis. Rarefaction is seen in the lower tibia associated with periosteal reaction in the same patient as in the previous images. Acute OsteomyelitisRadiograph of the foot (same patient as in the previous 2 images) shows periosteal reaction around the first metatarsal bone. Acute Osteomyelit

7、isA 2-year-old girl with proximal lower leg painan area of faint sclerosis at the lateral diametaphysis of the tibia.Acute pyogenic osteomyelitis Subacute Osteomyelitis An 11-year-old girl with ankle pain a lucent lesion with sclerotic margins. Radiographic feature of chronic osteomyelitisThe chroni

8、c phase of the disease is characterized by thick, irregular, sclerotic bone interspersed with radiolucencies, an elevated periosteum, and chronic draining sinuses.chronic osteomyelitis with significant bone sclerosis and deformity Chronic pyogenic osteomyelitis Sequestrum of the upper tibia. Chronic

9、 OsteomyelitisA 56-year-old man with diabetes shows chronic osteomyelitis of the calcaneum. Note air in the soft tissues. Garrs sclerosing osteomyelitis. a rare sclerotic nonpurulent form of osteomyelitis Note the bone expansion and marked sclerosis. 2-cm osteolytic lesionextensive sclerosis.A 6-yea

10、r-old girl with a history of chronic osteomyelitisBrodie abscessOsteomyelitis (Foot)soft tissue swelling (long arrows) rarefaction (lucency) of the fifth metatarsal head (short arrow) slight narrowing Osteomyelitis (Head and Neck)Osteomyelitis with periostitis. Axial CT (bony window setting) shows m

11、ultilayered periosteal reaction of irregular thickness in the right side of the mandible (arrowheads).Osteomyelitis (Head and Neck)Chronic suppurative osteomyelitis. Axial CT shows osteolytic and sclerotic changes in the right side of the mandible. Cortex has been destroyed (arrows).In general, infe

12、ctious arthritis is classified as pyogenic (septic) or nonpyogenic. Pyogenic septic arthritis is most frequently caused by Staphylococcus aureus. Infection can lead to rapid and severe joint destruction. Septic Arthritis(Pyogenic Arthritis)Radiographic featureThe earliest plain film radiographic fin

13、dings of septic arthritis are soft tissue swelling around the joint and a widened joint space from joint effusion. With progression of the disease, plain films reveal joint-space narrowing as articular cartilage is destroyed. Loss of visualization of the white cortical line over large areas of the j

14、oint surface soon ensues as bone destruction begins to develop. This is followed by marginal erosions as uncovered, intracapsular bone is destroyed. Plain film findings of superimposed osteomyelitis may develop (periosteal reaction, bone destruction, sequestrum formation).During the progression of i

15、nfectious arthritis of the hip, this image was obtained early in the disease and shows only concentric joint-space loss. During the progression of infectious arthritis of the hip, subchondral erosions and sclerosis of the femoral head are present. During the progression of infectious arthritis of th

16、e hip, 8 months after the initial examination, osteonecrosis and complete collapse of the femoral head are present. Septic arthritis. AP view of the shoulder demonstrates subchondral erosions and sclerosis in the humeral head. These are relatively late findings of septic arthritis. Periosteal reacti

17、on due to coincident osteomyelitis is present adjacent to the surgical neck of the humerus. Diabetic pedal infection: radiographic appearance. Osteomyelitis and septic arthritis - late. AP radiograph of the medial forefoot shows marked narrowing of the first MTP joint with adjacent bone destruction

18、and soft tissue swelling. Note periostitis (arrowheads) along the proximal phalanx.Acute Septic Arthritis the metacarpophalangeal joint of the index finger is seen as rarefaction of bone either side of the joint. Narrowing of the joint space and marginal erosion. Vertebral Osteomyelitis disc space n

19、arrowing (arrow) Lateral view of the lumbar spine demonstrates L 3-4 disc space narrowing (arrow) and end-plate irregularity. A. T1-weighted images of the lumbar spine demonstrate T1-hypointense signal (solid arrows) centered around the L3-4 interspace. B. Post gadolinium sagittal fat-suppressed T1-

20、weighted images shows marrow (dashed arrows) and disc enhancement with endplate erosions. Tuberculosis of bones and jointsThe most common tuberculous bone lesion is in the spine; the most frequent tuberculous arthritis is in the hip or knee. The great majority of tuberculous bone and joint lesions b

21、egin in childhood and adolescence.Tuberculous SpondylitisClinical HistoryA 37-year-old woman after bone marrow transplantation who presented with low-grade fever and back pain, undergoing computed tomography (CT).Tuberculous Spondylitis The patient was a 37-year-old woman with pulmonary tuberculosis

22、 and tuberculous spondylitis CT using lung windows shows a cavity in the apical segment of the right upper lobe. In the same patient, CT at the level of the lower thoracic spine using soft tissue windows shows paravertebral soft tissue masses and partial destruction of the adjacent vertebra.Spondyli

23、tis, TuberculousFigure : 31 year old man complaining of persistent neck pain. CT shows soft tissue mass with calcific debris and bone destruction. Thoracic vertebrae tuberculosisparavertebral abscessdisc narrowed Lumber vertebrae tuberculosisparavertebral abscessvertebral body destroyedTuberculosis

24、of long bonesFeatures:metaphyseal destroyedTuberculosis of long bonesFeatures:metaphyseal destroyedepiphysis invadedjoint invadedRadiographic featureA triad of radiographic abnormalities known as Phemister triad is characteristic of tuberculous arthritis: peripherally located bony erosions, juxta-ar

25、ticular osteoporosis, and gradual narrowing of the joint space. peripherally located bony erosionsOsteoporosisnarrowing of the joint spacebone tumorsOsteoid osteomaOsteoid osteoma is a benign skeletal neoplasm of unknown etiology that is composed of osteoid and woven bone. The tumor is usually small

26、er than 1.5 cm in diameter. Osteoid osteoma can occur in any bone, but in approximately two thirds of patients, the appendicular skeleton is involved. The skull and facial bones are involved exceptionally. Most patients with osteoid osteoma are young. The classic presentation is that of focal bone p

27、ain at the site of the tumor. The pain worsens at night and increases with activity; it is dramatically relieved with small doses of aspirin.Radiographic featureThe lesion initially appears as a small sclerotic bone island within a circular lucent defect. This central nidus is seldom larger than 1.5

28、 cm in diameter, and it may be associated with considerable overlying cortical and endosteal bone sclerosis. The tumors may regress spontaneously. The site of the tumor determines the degree of bone sclerosis. In medullary tumors, sclerosis is minimal or absent. Cortical and subperiosteal tumors pro

29、voke considerable sclerosis. Long-standing tumors demonstrate more sclerosis. Children also mount more of a sclerotic response than do adults. Transaxial CT scan through the proximal shaft of the right femur in a 17-year-old boy. The scan localizes the osteoid osteoma adjacent to the endosteal margi

30、n of the cortex. Note a central sclerotic focus in the radiolucent nidus, which is characteristic of osteoid osteoma. Osteoid Osteoma Figure : Axial image from a CT scan through the right femoral neck clearly shows a well-defined lucency with a central sclerotic focus (arrow).Osteoid Osteoma scleros

31、isnidusNidus surrounded by dense reactive bone Plain radiograph of the pelvis in a 6-year-old child who presented with left hip pain. The radiograph shows a well-defined area of sclerosis surrounded by a ring of radiolucency in the left femoral neck. Note the absence of periosteal reaction that sugg

32、ests intramedullary or cancellous osteoid osteoma. OsteosarcomaOsteosarcoma is the most common primary malignant tumor of bone, excluding plasma cell myeloma. It is most common among people aged 10 to 25, although it can occur at any age. Metaphysis of long bone,50% around the knee. Presentation: pa

33、in, mass, pathologic fracture Radiographic featureRadiographic appearances are variable, most lesions show a mixture of lytic and sclerotic areas. Rarely, purely lytic or sclerotic lesions occur. Lesions appear aggressive; they may appear moth eaten, with ill-defined edges.Soft tissue extension of o

34、steosarcoma is common; on radiographs, such extension is seen as a soft tissue mass. Cloudlike areas of sclerosis, resulting from malignant osteoid production and calcification, may be seen within the mass. Periosteal reactions are commonly seen once the tumor extends through the cortex. A spectrum

35、of changes occur; these include Codman triangles and multilaminated, spiculated, and sunburst reactions, all of which indicate an aggressive process. Osteosarcoma, Conventional (High Grade Intramedullary)mixed lytic with minor malignant osteoid production purely lyticpurely sclerotic Osteosarcoma, C

36、onventional (High Grade Intramedullary)Radiograph shows lysis, malignant osteoid formation, complex periosteal new bone formation and soft tissue extension. Conventional Osteosarcomaa large 7-cm bone-forming lesion involving the shaft of the femur with aggressive sunburst periosteal reaction. 22-yea

37、r-old male with leg pain Osteosarcoma(osteoblastic)Anteroposterior (AP) radiograph in a patient with osteosarcoma of the proximal humerus. Note the extensive soft tissue mass containing a considerable amount of mineralized osteoid. The radiograph shows mixed medullary sclerosis and lucency, cortical

38、 destruction medially, aggressive periosteal changes, and a large soft-tissue mass with peripheral ossification. Coronal T1-weighted MRI. Note the abnormal signal intensity in the metaphyseal marrow and the soft tissue mass (black arrow). Early tumor extension is shown beyond the growth plate into t

39、he epiphysis (white arrows). Osteosarcoma, ParostealParosteal osteosarcomas are typically densely ossified tumors arising from a broad base on the adjacent bone. Unlike osteochondromas, parosteal osteosarcomas involve no continuation of the medullary cavity into the tumor. The prognosis for a parost

40、eal osteosarcoma is generally excellent .37-year-old female with leg pain5-cm well-defined surface-based bone-forming lesion Giant cell tumorGiant cell tumor of the bone is a relatively uncommon tumor that is characterized by the presence of multinucleated giant cells. This type of tumor is usually

41、regarded as benign. By far most giant cell tumors are seen around the knee. Most common bone tumor in adults aged 25 - 40 y.Radiographic featureThe most important radiographic findings of giant cell tumor are the location of the tumor, its lytic nature, and the lack of a host response. GCT is locate

42、d in the epiphysis with or without extension to metaphysis and frequently abuts the articular surface. Typically, giant cell tumors are eccentric expansile, osteolytic radiolucent lesions without sclerotic margins and usually without a periosteal reaction. Septa, found in the image below, may be see

43、n in the lesion in 33-57% of patients; these represent nonuniform growth of the tumor rather than true septa. The tumors are typically in the range of 5-7 cm in diameter when they are discovered.A giant cell tumor presenting as an eccentric lytic lesion in the medial epi- and metaphysis of the dista

44、l femur. CT scan shows the full extent of a giant cell tumor in the left ilium. Septa are seen in the lesion. T2-weighted axial MRI of the knee shows multiple fluid-fluid levels in a giant cell tumor of the distal femur. On the left a giant cell tumor of the distal radius with ill-defined margins, d

45、estruction of the subchondral bone plate and extension towards the soft tissues. Metastatic tumor in boneMetastases are the most common malignant bone tumors.Bone metastases are often multiple at the time of diagnosis. In adults, the lesions generally occur in the axial skeleton and other sites with

46、 residual red marrow, although the lesions may be found anywhere in the skeletal system. Common sites for metastases are the vertebrae, pelvis, proximal parts of the femur, ribs, proximal part of the humerus, and skull. Most common osteolytic metastases: kidney, lung, colon and melanoma.Most common

47、osteosclerotic metastases: prostate and breast. Metastatic tumor in boneLateral radiograph shows sclerotic metastasis of the L2 vertebra in a 54-year-old man with prostatic carcinoma. Radiograph shows osteolytic metastasis in the distal femur of a 51-year-old woman with breast carcinoma. Axial CT sc

48、an shows 2 rounded, mixed osteolytic-sclerotic lesions in the thoracic vertebral body of a 44-year-old woman with lung carcinoma. The bulls-eye or halo sign has been reported to be useful in distinguishing metastatic from benign lesions. In vertebrae, additional criteria for malignancy include bulgi

49、ng of the posterior margin of the vertebral body, signal intensity changes that extend into the pedicle, and paraosseous tumor spread .A 68-year-old man with thyroid carcinoma. This image shows heterogeneous enhancement of the T11-L2 vertebrae, with prominent epidural component enhancement and spina

50、l canal compromise. caseA 13-year-old boy complained of malaise, weight loss and a progressive painful swelling over the distal left thigh for 3 months. There was no fever or history of recent trauma. Physical examination showed a hard mass over the distal thigh with mild localized tenderness. The l

51、eft knee was unremarkable. Laboratory investigations revealed raised ESR and normal WBC. In view of the history, radiographs of the distal femur were performed (Fig.).Questions(1) What abnormalities do you see on this radiograph ?Overlying soft tissue mass Spiculated new bone formationCortical thinn

52、ing and disruptionA mixed osteolytic and sclerotic lesion with ill-defined margins (2) What is the diagnosis ?OsteosarcomaCommon chronic diseases of jointsDegenerative arthritis(osteoarthritis)Rheumatoid arthritisGouty arthritisDegenerative arthritis(osteoarthritis OA)ClassificationPrimary osteoarth

53、ritis - most common in the older age group as the result of wear and tear on articular cartilage over time. Secondary osteoarthritis - results from a previous process that damaged cartilage such as trauma, or inflammatory arthritis. The most commonly involved joints in primary osteoarthritis are:Dis

54、tal interphalangeal joints First carpometacarpal joint Weight bearing joints: spine, hips, knees Diagnosis by plain films includes identification of:Asymmetric joint space narrowing Osteophytes-bony spurs Degenerative cysts Sclerosis of subchondral bone degenerative arthritis(osteoarthritis)Features

55、:1, Asymmetric narrowed joint space 2,subarticular reactive sclerosis3,spur formationCervical verterbranormaldegenerativenarrowed joint spacespur formationLumber vertebra degenerationLumber vertebra degenerationOA of the Hipjoint space is almost completely obliterated sclerosis and osteophyte format

56、ion (arrow). narrowing of the joint spaces and the increased density around the joints due to the subchondral sclerosis (black arrows). osteophytes (white arrow). OA of the Fingerssubchondral sclerosis asymmetric disk space osteophytes Rheumatoid arthritis(RA)Diagnosis usually made by plain film confirmation of:Osteopenia - a demineralization of the bone - is t