داليا الفلكي

BONE IMAGING

Presented byDr Dalia Al –FalakiDepartment of RadiologyColleage of medicine

BONE INFECTION( OSTEOMYELITIS ):

Method of infection : 1- direct invasion from infected wound ,or infected joint, . 2- haematogenous spread from distant focus , usually in the skin ,haematogenous osteomyeltis ,usually ocur during period of growth but all ages may be affected.

BONE INFECTION( OSTEOMYELITIS

RADIOLOGICAL FEATURE: 1- soft tissue changes may be immediately appearant especially in infant , swelling with edema and blurring of fat planes, ( fat plane is displaced in case of tumor ). 2- osteoporosis may be seen within 10 -14 days of oncet of symptoms, in children this is usually metaphyseal. 3- periosteal reaction due to periosteal elevation by pus material, result in involcrum new bone formation around the old bone ( seqesrum ).

BONE INFECTION( OSTEOMYELITIS ):

4-infection process lead to bone destruction , dead bone formation called sequestrum ,and lead to pus formation around the dead bone which escape through holes inside the involcrum , these are called cloacae, through these single or multiple opening the pus and the sequestra get out. 5- with adequate treatment in infant and children a return to normal appearance with normal growth is expected unless the epiphyseal plate & epiphysis have been damged, in adult the affected bone often remain sclerotic & irregular in outline.

Osteolytic lesion, bone rarefaction

Medulaary osteolytic lesion + periosteal reaction

Bony desructive lesion ; peristeal reaction ‘ soft tissue swelling

Conventional tomofgram
Show inflammatory lesion inside left clavicle

Chronic osteomylitis = fat suppressed sequence on MRI show bone marrow edema
High signal intensity area inside left clavicle compare with normal low signal intensity right clavicle

Sequestrum

SPECIAL FORM OF OSTEOMYLITIS
1- BRODIE,S ABSCESS :Is localized form of osteomyelitis , found in cancellous bone near the end of long bone , seen as well defind focal area of bone destruction has a surrounding zone of reactive sclerosis , sometimes accompanied by periosteal reaction.

Brodies abscess

Brodies abscess



SPECIAL FORM OF OSTEOMYLITIS
2- SCLEROSING OSTEOMYLITIS OF GARR,E Localized area of abnormal marked sclerosis and thickening of bone in the absence of appearant bone destruction.( to be distinguished from osteoid osteoma which is benign bone tumor which is associated with central osteolytic lesion called nidus).

Sclerosing osteomylitis

Sclerosing osteomylitis of lower tibia

PYOGENIC ARTHRITIS ( INFECTION OF JOINTS )

1- In early stage there is widening of joint space due to synovial effusion. 2-reduction in density of the adjacent bone ( hyperaemia , disuse ) 3-destruction of articular cartilage lead to narrowing of joint space and subluxation. 4-if infection process proceeds there will be destruction of subchondral bone. 5- joint deformities like subluxation, dislocation. 6- in healing stage there will be fibrous then bony ankylosis ( obliteration of joint space & aquired fusion of both articular bone surfaces).

Tuberculosis of the bone

1- the metaphysis is the site of election,which soon crosses the epiphyseal line( the initial focus of infection may be sited in the epiphysis ). 2-the T.B. lesion is destructive , osteolytic & accompanied by pus formation. 3- in contrasistinction to pyogenic osteomyelitis neither sequestra nor periosteal reaction is a prominent feature ( sequestrum is small or absent , periosteal reaction is minimum). 4- no surrounding sclerosis. 5- T.B. of dactylitis ( spina ventosa ) the affected phalanx is widened by medullary expantion.

T.B OF HIP

Tuberculous dactylitis

T.B. OF SPINE ( T.B. Arthritis )

Most lesion occur in or below midthoracic spine 2- two or more vertebrae may be affected. 3- vertebral bodies may be 1st affected in three places: at upper or lower disc margin, in the center , & anteriorly under the periosteum. 4- disc substance is eroded lead to narrowing of the inter vertebral disc space. 5- since the anterior parts of the vertebrae are most affected by destruction, local angular kyphos or gibbus will appear. 6- para vertebral abscess ( cold abscess ).

Focal angular kyphosis & paraspinal abscess

Pott;s disease thoracic vertebra

MRI T.B OF SPINE

ARTHRITIS
Rheumatoid arthritis Disease is seen in all ages but especially from 20 to 55 years. Female are more commonly affected ( 1:3). The joints most typically involved are small joints especially metatarsophalangeal, metacarpophalangeal joints , carpal joint, but any joint can be involved including the temporomandibular joints. Pathogenesis formation of pannus in he synovium.

Rheumatoid arthritis

RADIOLOGICAL FEATURE 1- bilateral symmetrical fusiform soft tissue swelling around the joints. 2-juxtaarticular osteoporosis. 3-periarticular erosion on both surfaces of the joints. 4- the joint space is widened at first due to synovial effusion then narrowed due to joint cartilage destruction. 5- deformities of the joints in form of subluxation, ulnar deviation, variable degree of ankylosis. 6- carpal bones of the wrist are affected ,with loss of joint spaces, resorption of styloid process of ulna, cystic changes in the carpal bones.

EROSION

SYMMETRICAL JUXTA ARTICULAR OSTEOPENIA

GOUTTY ARTHRITIS

Due to increased level of uric acid & deposition of urate crystal in the in the soft tissue RADIOLOGICAL FEATURE : Usually in the big toe


GOUTTY ARTHRITIS
1- punched out erosion tend to appear near joint margins. 2-associated with tophi which are eccentric soft tissue swelling, soft tissue tophi may calcify ( tophi formation is due to depositin of crystal in the soft tissue, ear lobule and around the knee joint). 3-osteoporosis is not prominent.

EROSION IN GOUT

Ankylosing spondylitis
It is destructive arthritis affects joints Early changes : it affects sacroiliac joints: 1-articular surface erosions. 2- juxta articular osteoporosis. 3-resorption of subarticular bone. 4-joint space is widened first then narrowed and obliterated due to destruction of the articular cartilage.

Ankylosing spondylitis

Late changes: Due to repair by osteoblastic activity, sclerosis and reossification. This lead to : ankylosis of sacroiliac joints. 2- spinal changes include: A. deposition of new bone at anterior surface of the vertebral bodies at their concavity lead to sequaring of the vertebral bodies. B. calcification of the paraspinal, interspinous, two lateral spinal ligaments causing bampoo spine. C. disc space remain normal not affected but he disc may show calcification.

OSSIFICATION OF ANNULOUS FIBROSUS =BAMBOO SPINE

OSTEOARTHROSIS
Either primary or secondary. Primary: it id a degenerative affects normal joints. Secondary : it complicate previously abnormal joints.

OSTEOARTHROSIS

Radiological feature: 1-non uniform narrowing of joint space , due to articular cartilage destruction. 2- marginal osteophytes formation, sometimes separated from the margin of bone and result in loose body formation. 3- sclerosis of subchondral bone. 4- subarticular cyst formation. 5- neither osteoporosis nor ankylosis occur.

OSTEOARTHROSIS

EXAMPLES Osteoarthrosis of he knee joints: 1-narrowed joint space usually the medial aspect. 2- spiking of the tibial spine. 3- marginal osteophytes formation. 4- subchondral sclerosis.

O.A. of the spine:

Affect cervical , dorsal, lumber spine: 1- loss of the normal height of the intervertebral disc. 2-marginal osteophytes formation. 3- articular surface irregularity and sclerosis.

O.A. of hip joints

1- narrowing of joint space usually superolateral or medial part of joint space. 2- marginal osteophytes formation. 3- subchondral sclerosis. 4- cystic changes of the subchondral bone.

OSTEOPENIA

OSTEOPENIA This is radiological term i.e. reduction in the bone density, which can occur in disease like ricket, osteoporosis, osteomalacia, multiple myeloma & hyperparathyroidism.