Search my links!

Monday 30 May 2011

Rheumatoid arthritis



    early signs:
  • fusiform periarticular soft tissue swelling (result of effusion)
  • regional osteoporosis (disuse and local hyperemia)
  • widened joint space
  • marginal + central bone erosion (base of 4th proximal phalanx most common)
  • change in ulnar styloid (erosions) and distal radioulnar joint
  • atlantoaxial dislocation
  • giant synovial cysts

    late signs:
  • flexion/extension contractures with ulnar subluxation/dislocation
  • destruction/fusion of joints
  • elevation of humeral heads (tear/atrophy of rotator cuff)
  • resorption of distal clavicle
  • erosion of superior margins of posterior portions of 3-5th ribs
  • destruction/narrowing of disc spaces
  • destruction of zygapophyseal joints without osteophyte formation
  • resorption of spinous process
  • protrusio acetabuli (from osteoporosis)

The radiographic hallmarks of rheumatoid arthritis are:

  • soft tissue swelling : fusiform and periarticular. It represents a combination of joint effusion, oedema and tenosynovitis . This can be an early/only radiographic finding.
  • osteoporosis that is initially juxta-articular, and later generalised. It is compounded by corticosteroid therapy and disuse.
  • joint space narrowing : symmetrical or concentric.
  • marginal erosions : due to erosion by pannus of the bony “bare areas”.
Hands and wrists

Diagnosis and follow-up of patients with RA commonly involves imaging of the hands and wrists. The disease tends to involve the proximal joints in a bilaterally symmetrical distribution.

There is predilection for:

  • PIP and MCP joints (especially 2nd and 3rd MCP)
  • ulnar styloid
  • triquetrum

As a rule, the DIP joints are spared.

Rheumatoid arthritis

Rheumatoid Arthritis Hands

Late changes include :

Feet
  • similar to the hands, there is a predilection for the DIP and MTP joints
  • involvement of subtalar joint
  • calcaneal erosions
Shoulder
Hip
  • concentric loss of joint space (cf osteoarthritis where there is tendency for superior loss of joint space)
  • acetabular protrusio
Knee
  • joint effusion
  • loss of joint space involving all three compartments
  • lack of subchondral sclerosis and osteophytes (cf OA)
Spine

The cervical spine is frequently involved in RA, whereas thoracic and lumbar involvement is rare.

Findings include :



LINKS:

Images: google images, www.radiopedia.org

No comments:

Post a Comment