Diagnostic Imaging Week 3- Arthritis of the Extremities

What is the most common form of arthritis

DJD

What are the main symptoms of DJD

-Pain

-Stiffness

-Crepitus

-Deformity

-Swelling

-Normal lab studies

What are the 3 types of DJD

Primary

Secondary

Erosive osteoarthritis

What are the features of primary DJD (cause, age, sex, joint)

-unknown cause

-5th-6th decade

-females 10:1

-weight-bearing joints

What are the features of secondary DJD (cause, age, sex, joint)

-known cause

-2nd-6th decade

-equal sex distribution

-any joint

What is the pathology of DJD

-Begins focally, increases in size

-Loss of chondroitin sulphate leads to break down of articular cartilage and adjacent bone

-Synovial fluid escapes in subchondral bone, forming subchondral bone cysts

What are the main radiological features of DJD

-Osteophytes

-Subchondral sclerosis

-Non-uniform joint space narrowing

-Subchondral cysts

-Loose bodies

-Asymmetrical distribution

-Subluxation

What is the colour of the cortices in CT vs MRI scans?

CT: white

MRI: black

Rheumatoid arthritis demographic

-Onset typically 20-60 y/o

-Highest incidence 40-50 y/o

-Under 40 = Females 3:1

-Over 40 = Equal sex distribution

What are the radiological features of rheumatoid arthritis

-Uniform loss of joint space

-Marginial erosion

-Subchondral bone cysts

-Juxta-articular osteoporosis

-Ankylosis

-Boutenniere and swan neck deformity

-Subcutaneous soft tissue mass

-Enthesopathy

In what condition is protrusio acetabuli often seen? How do you detect it?

-Rheumatoid arthritis

-Align most lateral aspect of greater sciatic notch with obturator foramen

-Draw line done

-If femoral had crosses the line, it is positive

What are the main features of Erosive Osteoarthritis (EOA) (sex, age, type, location)

-Females

-40-50 y/o

-Inflammatory

-Seronegative

-DIPs and PIPs

What are the main radiographic features of EOA

-Non-uniform loss of joint space

-Sclerosis

-Osteophytes

-Gull wing erosions

-Periostitis

-Deformity

What's the main difference between psoriatic arthritis and erosive osteoarthritis

-PA: Mouse ears

-EOA: Gull wings

-PA maintains bone mineralisation adjacent to the involved joint, EOA does not

What are the main affected areas of PA

-DIPs

-Small joints of the feet

-SIJ

-Spine

-Occasionally knee, hip, shoulder

What are the main radiographic findings of PA

-Asymmetric distribution

-Normal bone mineralisation

-Mouse ear erosions (erosion+ fluffy periostitis)

-Narrow or widened joint space

-Pencil in cup deformity

-Bony ankylosis

-Acro osteolysis

-Os trigonum

-Enthesitis

-Ivory phlanax

-Sacrolitis

-Non- marginal syndesmophyte formation

What are the main features of PA (age, presentation)

-20-50 y/o

-Sausage digits

-Skin lesions

-Presence of nail changes

-DIPs

-Seronegative (ESR normal)