joints

Prepared by Dr.Salah Mohammad FatihMBChB,DMRD,FIBMS(radiology)

Lecture no 4

Inflammatory arthritis

Rheumatoid Arthritis

Radiological features of RA

OA•Joint space narrowed max. at wt bearing site•Erosion do no occur.

•Subchondral sclerosis may be seen.

•Sclerosis is a prominent feature.

•No osteoporosis.

•No peri articular soft tissue swelling

RA•Joint space narrowing uniform.

•Erosion is characteristic feature.

•Subchondral sclerosis is not a feature.

•Sclerosis not a feature unless there is secondary OA.

•Osteoporosis often present

•Peri articular soft tissue swelling

OA RA

Ankylosing spondylitis

Radiological features

Gout

Radiological features of gout

Joint infection

Most often due to pyogenic bacterial infection or TB.

Usually only one joint affected. Synovial biopsy or exam. of the joint fluid is

necessary for identification of infecting organism

Usually due to staph. Aureus. Rapid destruction of the articular cartilage

followed by destruction of the subchondral bone & cause peri articual soft tissue swelling.

Earliest radiological finding is joint effusion, do US, you can do US guided aspiration of the joint fluid.

If Dx is still in doubt , then MRI advisable

Pyogenic infection

Radiological features of pyogenic joint infection

There is decrease in cartilage width in the left hip, and cortical indistinctness in the left acetabulum with subarticular cyst formation.

Hip& knee are the most commonly affected peripheral joints.

Spine involved in 50% of cases.

TB arthritis

Localized osteoporosis. Cartilage erosion usually occur late for that

resion , at 1st joint space is preserved. Margional errosion. At late stage there may be gross

disorganization of the joint with calcified debris near the joint.

Radiological features

Neuropathic joint (Charcot joint)

•Common causes;

•DM•Spinal cord injury•Myelomeningocele/ syringomyelia.•Alcohol abuse.

Radiological features

•classic picture of a Charcot joint. It demonstrates the five Ds:

•increased or normal density,• joint distension (effusion), •bony debris.• joint disorganization• joint disassociation.

•lateral translation of the tibia relative to the femur;• a destructive arthropathy with loss of cartilage width and fragmentation, especially of the medial tibial plateau; •large effusion containing bony debris.

•Changes seen in the feet in the pt with diabetic neuropathy.

•Prominent feature is Resorption of the bone ends & calcification of the arteries in the feet often present

complete obliteration of the cartilage width and destruction with very abundant fragmentation at this joint.

Avascular(aseptic) necrosis

• Also known as osteonecrosis, is where there is death of bone due to interruption of the blood supply.

• It occur most commonly in the intra-articular portions of bones & is associated with numerous underlying condition including.

• Steroid therapy.• Collagen vascular diseases.• Radiation therapy.• Sickle cell disease.• Exposure to the high pressure environment e.g. deep-

see divers

X-ray finding

•Increased density of the subchondral bone with irregularity of the articular contour or even fragmentation

• A charactristic lucent line may be seen just beneath the articular cortex.

•The cartilage space may be preserved until secondary OA changes occur.

left hip joint;increased density centrally and flattening of the femoral head in the weight-bearing region, as well as the crescent sign or subchondral fracture.

MRI

•Is imaging modality of choice.

•It can show abnormality when the X-ray is normal & signal pattern allow specific Dx to be made.

The MR, shows that this patient has bilateral avascular necrosis of the hip joints, with a low-signal rim surrounding the necrotic segments

osteochondritis

•Is a group of condition in which no associated cause for avascular necrosis can be found.

•Osteochondritis now regarded as being due to impaired blood supply associated with repeated trauma.

Perthe’s disease

•Is avascular necrosis of the femoral head in children.

•seen generally between ages 4 and 8, when the vascular supply to the femoral head is most at risk.

• Males are affected more than females. •Bilateral in 10 percent of patients.

X-ray finding

•The first radiographic sign may be effusion.

• Later, increased density, fragmentation and flattening of the ossification center & lucent areas within it

• •Metaphyseal irregularity & short wide

femoral neck.

The left femoral capital epiphysis is dense, has lucent areas within it, and is flattened. This left hip is laterally subluxated,

Other forms of osteochondritis

•Kienbock’s disease = avascular necrosis of lunate bone.

•Freiberg’s disease = avascular necrosis of metatarsal head.

•Kohler’s disease = avascular necrosis of navicular bone of the foot.

There is increased density and collapse of the lunate

Kienbock's disease

Freiberg’s disease

Osgood-schlatter’s disease = avascular necrosis of tibial tuberosity .

Fragmentation of tibial tuberosity

Kohler’s disease = avascular necrosis of navicular bone of the foot.

Increased density with irregularity in the out line

Slipped femoral epiphysis

.

• age range (10 to 16 years of age)

• Males are more commonly affected than females.

• bilateral 20 percent of the time, but rarely symmetric.

• Slipped epiphyses almost always are directed posteromedially.

Radiological finding

• The epiphysis itself appears shorter due to the posterior slippage.

• The epiphyseal plate itself appears wider, with less distinct margins

• The epiphysis is also slightly more medially placed, it can be demonstrated by drawing a line along the lateral femoral neck. This line should intersect a portion of the femoral head in the normal individual. In a slipped epiphysis, the line will either not intersect the femoral head, or will intersect a smaller portion of it.

• The slip is best appreciated in lateral film of the hip

The left femoral capital epiphysis appears slightly shorter than does the right, with an apparent widening of the epiphyseal plate

Developmental dysplasia of the hips (DDH or CDH)

developmental dysplasia of the hips (CDH or DDH)

•female: male = 6:1

•70% occur on the left side, Bilateral involvement occur in 5%

Radiographic finding

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