psoriatic arthritis

Anteroposterior
X-rays of left hand in a patient with Psoriatic arthritis
Wikipedia • Public domain
A classic
case of psoriatic arthropathy. Marginal erosion with fluffy periostitis seen predominantly involving various DIP joints and few PIP joint. Ray sign in second digit of right hand. Bony ankylosis also seen at various interphalangeal joints.
www.eurorad.org • CC by-nc-sa-4.0
Magnetic
resonance images of fingers: psoriatic arthritis with dactylitis due to flexor tenosynovitis. Shown are T1 weighted axial (a) precontrast and (b) postcontrast magnetic resonance images of the fingers from a patient with psoriatic arthritis exhibiting flexor tenosynovitis at the second finger with enhancement and thickening of the tendon sheath (large arrow). Synovitis is seen in the fourth proximal interphalangeal joint (small arrow).
Wikipedia • CC BY 2.0
Magnetic
resonance image of index finger: psoriatic arthritis (mutilans form). Shown is a T2 weighted fat suppressed sagittal image of the index finger in a patient with PsA (mutilans form). Focal increased signal (probable erosion) is seen at the base of the middle phalanx (long thin arrow). There is synovitis at the proximal interphalangeal joint (long thick arrow) plus increased signal in the overlying soft tissues indicating oedema (short thick arrow). There is also diffuse bone oedema (short thin arrows) involving the head of the proximal phalanx and extending distally down the shaft.
Wikipedia • CC BY 2.0
Magnetic
resonance images of fingers: psoriatic arthritis. Shown are T1-weighted (a) precontrast and (b) postcontrast coronal magnetic resonance images of the fingers in a patient with psoriatic arthritis. Enhancement of the synovial membrane at the third and fourth proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints is seen, indicating active synovitis (large arrows). There is joint space narrowing with bone proliferation at the third PIP joint and erosions are present at the fourth DIP joint (white circle). Extracapsular enhancement (small arrows) is seen medial to the third and fourth PIP joints, indicating probable enthesitis. Note that this particular slice does not allow optimal visualization of all of the mentioned pathologies.
Wikipedia • CC BY 2.0
Magnetic
resonance images of lumbar and lower thoracic spine: psoriatic arthritis. (a) T1-weighted and (b) short tau inversion recovery (STIR) magnetic resonance images of the lumbar and lower thoracic spine. Signs of active inflammation are seen at several levels (arrows). In particular, anterior spondylitis is seen at level L1/L2 and an inflammatory Andersson lesion at the upper vertebral endplate of L3.
Wikipedia • CC BY 2.0
Magnetic
resonance images of sacroiliac joints: psoriatic arthritis. Shown are T1-weighted semi-coronal magnetic resonance images through the sacroiliac joints (a) before and (b) after intravenous contrast injection. Enhancement is seen at the right sacroiliac joint (arrow), indicating active sacroiliitis.
Wikipedia • CC BY 2.0
Psoriasisarthritis
distales Interphalangealgelenk mit typischem Pencil-in-Cup Bild.
Wikipedia • CC BY-SA 4.0
Lost bones:
differential diagnosis of acro-osteolysis seen by the pediatric rheumatologist. Frontal radiograph of the toes in a 14 year old female patient with juvenile psoriatic arthritis demonstrates focal soft tissue swelling of the fourth digit, with tapering of the distal phalanx and resorption of the distal tuft cortex
ped-rheum.biomedcentral.com • CC-by-4.0
Sagittal
magnetic resonance images of ankle region: psoriatic arthritis. (a) Short tau inversion recovery (STIR) image, showing high signal intensity at the Achilles tendon insertion (enthesitis, thick arrow) and in the synovium of the ankle joint (synovitis, long thin arrow). Bone marrow oedema is seen at the tendon insertion (short thin arrow). (b,c) T1 weighted images of a different section of the same patient, before (panel b) and after (panel c) intravenous contrast injection, confirm inflammation (large arrow) at the enthesis and reveal bone erosion at tendon insertion (short thin arrows).
Wikipedia • CC BY 2.0
A classic
case of psoriatic arthropathy. Fixed flexion deformity with onycholysis.
www.eurorad.org • CC by-nc-sa-4.0
A classic
case of psoriatic arthropathy. Psoriatic enthesopathy with "pencil in cup" deformity.
www.eurorad.org • CC by-nc-sa-4.0
A classic
case of psoriatic arthropathy. Bilateral asymmetrical sacroiliitis with bagpipe type of syndesmophytes.
www.eurorad.org • CC by-nc-sa-4.0
A classic
case of psoriatic arthropathy. Non-marginal syndesmophytes.
www.eurorad.org • CC by-nc-sa-4.0
A classic
case of psoriatic arthropathy. Non-marginal syndesmophytes.
www.eurorad.org • CC by-nc-sa-4.0
A classic
case of psoriatic arthropathy. Bony ankylosis with minimal joint deformity seen at wrist joints.
www.eurorad.org • CC by-nc-sa-4.0
Radiopaedia • CC-by-nc-sa 3.0 • de

Psoriatic arthritis (PsA) is an inflammatory arthritis associated with psoriasis. It is usually negative for rheumatoid factor and hence classified as one of the seronegative spondyloarthritides.

Epidemiology

Overall prevalence is ~0.5% (range 0.1-1%), however, it affects up to ~25% (range 6-41%) of patients with psoriasis . In contrast to many other arthropathies, there is no gender predilection in psoriatic arthritis. The median age of diagnosis is 48 years .

Clinical presentation

Dermatological features of psoriasis precede arthritis in ~65% (range 60-70%) whereas arthritic symptoms proceed dermatological features in 15-20% . There is a strong association with nail involvement, particularly for distal interphalangeal joint arthritis. It most commonly presents as an asymmetrical oligo-arthritis with spondylitis common; oligo-arthritis may progress to polyarthritis in the clinical course of the disease .

Pathology

Both environmental and genetic factors are thought to play a role. Up to 60% are HLA-B27 positive . A proportion of patients have serum rheumatoid factor .

Extra-articular manifestations are common :

  • ocular: uveitis, conjunctivitis
  • gastrointestinal: inflammatory bowel disease
  • cardiac: rhythm disturbances (e.g. bundle branch block)
  • urogenital: urethritis, prostatitis, balanitis, cervicitis, vaginitis
Classification

One of the classification systems is the one by Moll and Wright, which classifies PsA into five subtypes:

  • symmetric polyarthritis (similar in appearance to RA)
  • asymmetric mono- or oligoarthritis
  • spinal column involvement (spondylitis)
  • distal interphalangeal arthritis of the hands and feet
  • arthritis mutilans
    • Associations

    PsA is associated with :

    Radiographic features

    The hallmark of PsA is the combination of erosive change with bone proliferation, in a predominantly distal distribution (e.g. interphalangeal more than metacarpophalangeal joints). The disease most commonly involves the hands, followed by feet. It can also affect sacroiliac joints and spine. Knees, elbows, ankles, and shoulders are less frequently involved .

    In the hands and feet, the pattern of distribution may be that of a symmetric polyarthropathy, or asymmetric oligoarthropathy, with a distal predominance.

    Imaging findings include:

    • enthesitis and marginal bone erosions; "pencil-in-cup" deformities are common, but not pathognomonic for PsA
    • bone proliferation results in an irregular, “fuzzy” appearance to the bone around the affected joint
    • joint subluxation or interphalangeal ankylosis may be present
    • periostitis: may appear as a periosteal layer of new bone, or as irregular thickening of the cortex itself
    • dactylitis: which can present as a “sausage digit” which refers to soft tissue swelling of a whole digit; ultrasound examination of a sausage digit demonstrates underlying synovitis and tenosynovitis
    • acro-osteolysis 
    • arthritis mutilans: osteolysis and articular collapse can cause a phenomenon referred to as "telescoping fingers"
    • ivory phalanx: classically involving the distal phalanx of the great toe
    • sacroiliitis: often asymmetrical
    • spondylitis: asymmetric paravertebral ossifications and relative sparing of the facet joints

    Differential diagnosis

    General imaging differential considerations include:

    Siehe auch:
    und weiter:
    Assoziationen und Differentialdiagnosen zu Psoriasisarthritis:
    Gicht
     
    Wikipedia • CC BY-SA 3.0
    Rheumatoide
    Arthritis
    Wikipedia • CC BY 3.0
    Protrusio
    acetabuli
    Wikipedia • CC BY-SA 4.0
    Osteoporose
     
    Wikipedia • CC BY-SA 4.0
    erosive
    Arthrose
    Wikipedia • CC BY-SA 3.0