Arthritis Overview

Arthritis Overview

Exam

·        Screening exam (OHCS, p 666):

o   Observe from behind: muscle bulk (shoulders, buttocks), straight spine, swellings, deformities

o   Observe from the side: cervical and lumbar lordosis, thoracic kyphosis

o   Touch your toes: spine and hip flexion

o   Observe from in front

o   Ear to shoulder: lateral cervical flexion, flexion, extension and rotation

o   Open and close the mouth: TMJ, orofacial pain

o   Hands behind head: shoulder and sternoclavicular movement, then straight above

o   Arms straight: elbow extension

o   Examine hands: nails, pray sign, press dorsum of both hands together

o   Observe legs: bulk, swelling, deformity

o   Knee effusion

o   Observe feet

o   Observe walking

Differentials for Arthritis

Causes of Monoarthritis

·        Acute Monoarthritis:

o   Septic arthritis: either haematogenous (staph or gonococcal) or following penetrating injury

o   Traumatic

o   Gout, pseudogout

o  Haemarthrosis (eg haemophilia)

o  Sometimes seronegative spondyloarthritis

·        Chronic monoarthritis:

o  Chronic infection (eg Tb)

o  Osteoarthritis

o  Seronegative spondyloarthritis

o  Metastasis

Causes of Polyarthritis

·        Acute polyarthritis

o  Infection: viral (mumps, rubella, EBV, etc), bacterial

o  Rheumatic fever

o  Onset of chronic polyarthritis

o  Drug allergies

·        Chronic polyarthritis:

o  Rheumatoid arthritis

o  Seronegative spondyloarthritis

o  Primary osteoarthritis

o  Gout, pseudogout or hydroxyapatite arthropathy

o  Connective tissue disease (eg SLE)

o  Infection (eg Tb)

Differential by Distribution

·        Inflammatory:

o  Peripheral, symmetrical, small joint polyarthritis:

§  RA

§  Lupus and Connective Tissue Diseases (non-deforming and non-nodular) 

o  Asymmetrical, large joint, oligoarthritis, possibly with spinal disease: Sero-negative spondyloarthropathies:

§  Ankylosing Spondylitis

§  Reactive Arthritis and Reiter‟s Disease

§  Psoriatic Arthritis

§  Arthritis of IBD

o  Acute inflammatory mono or oligo arthritis: septic arthritis or gout

·        Non-inflammatory:

o  Osteoarthritis: weight bearing joints or hands

o  Soft tissue or locomotor pain syndromes

·        Sacro-ilitis: occurs in Ankylosing Spondylitis, Reiter‟s Syndrome, Crohn‟s Disease, Chronic

·        Polyarthritis

Causes of Arthritis and Nodules

·        Rheumatoid arthritis

·        SLE (rare)

·        Rheumatic fever (very rare)

·        Granulomas, eg sarcoid (very rare)

Raynaud’s Syndrome

·        Episodic digital ischaemia, precipitated by cold or emotion

·         Fingers ache and go pale ® blue ® red/purple (pain most severe in this stage, during reperfusion)

·        May be:

o  Idiopathic: Raynaud‟s disease 

o  Associated with underlying cause (Raynaud‟s phenomenon): Scleroderma, SLE, RA, arteriosclerosis, leukaemia, drugs, etc. Not polyarteritis nordosa

·        Keep warm, stop smoking, try Ca channel blockers (eg diltiazem)

Radiology

·        Principles: Looking for:

o  Morphologic change in an individual joint

o  The skeletal distribution

·        Features:

o   Joint space narrowing, either localised or uniform

o   Erosions (if at the margin then periarticular erosions)

o   Osteophytes: bony lip at edge of joint

o   Subchondral cysts: formed by synovium getting through fissures in the cartilage 

o   Subchondral Sclerosis: micro-fractures in the subchondral bone ® attempted repair ® dense white band 

o   Periarticular osteopenia: cytokine mediated thinning of the surrounding bone (check other joints)

o   Periarticular soft tissue swelling:

§  Fusiform: in inflammatory

§  Asymmetric: in gout

·        Features of different arthropathies:

o   Other arthropathies are variations on this: 

§  Secondary osteoarthritis (eg due to previous trauma or infection). Looks like OA but not standard (eg uniform joint space) 

§  If inflammatory but wrong distribution ® ?sero-negative

·        Idiot‟s rule of thumb for hand arthritis:

o   Rheumatoid: MCP and MTP joints

o   Psoriasis: PIP joints

o   Osteoarthritis: DIP