F:\clinical series`arthitis

CLINICAL SERIES:

ARTHRITISBY: Ahmed AL-Jabri R2

AIM

• JOINT inflammation : Articular vs periarticular ?

• Inflammatory vs non-inflammatory ? • focus on septic arthritis AND crystal induced

arthritis

Normal Joint..Normal Joint..

Articular Vs. Periarticular

Clinical feature Articular Periarticular

Anatomic structure

Painful site

Pain on movement

Swelling

Synovium, cartilage, capsule

Diffuse, deep

Active/passive, all planes

Common

Tendon, bursa, ligament, muscle, bone

Focal “point”

Active, in few planes

Uncommon

Inflammatory Vs. Noninflammatory

Feature Inflammatory Noninflammatory

Pain (when?)

Swelling

Erythema

Warmth

AM stiffness

Systemic features

î ESR, CRP

Synovial fluid WBC

Examples

Yes (AM)

Soft tissue

Sometimes

Sometimes

Prominent

Sometimes

Frequent

WBC >2000

Septic, RA, SLE, Gout

Yes (PM)

Bony

Absent

Absent

Minor (< 30 ‘)

Absent

Uncommon

WBC < 2000

OA, AVN

Inflammatory Vs. Noninflammatory

Feature Inflammatory Mechanical

Morning stiffness

Fatigue

Activity

Rest

Systemic

>1 h

Profound

Improves

Worsens

Yes

< 30 min

Minimal

Worsens

Improves

No

Acute Monoarthritis - differential diagnosis

– Septic arthritis

– Crystal arthritis• Gout (uric acid)• Pseudogout/calcium pyrophosphate deposition disease

(CPPD)

What are other differentials foracute monoarticular pain?

Monoarthritis - differential diagnosis

Psoriatic arthritis– Onycholysis– Subungual hyperkeratosis– Pitting– Extensor surfaces, scalp, natal

cleft, umbilicus– Other associated features eg

uveitis, inflammatory bowel disease, enthesitis, Ankylosing spondylitis

Monoarthritis - differential diagnosis

Reactive arthritis• Prodromal GI /GUInfection egcampylobacter, salmonella, shigella, Yersinia,chlamydia• Pustular psoriasis and • circinate balanitis

Q: Physical examination of a patient with reiter’s syndrome may be expected to reveal :

• Waxy plaques on the palms and soles• Sausage-like swelling of the fingers• Painful, shallow ulcers in the mouth• Iritis• All of the above • Non of the above

Q: Physical examination of a patient with reiter’s syndrome may be expected to reveal :

• Waxy plaques on the palms and soles• Sausage-like swelling of the fingers• Painful, shallow ulcers in the mouth• Iritis• All of the above

Monoarthritis - differential diagnosis

– Trauma - # and haemarthroses (warfarin, bleeding disorders)

Others to think about• Osteonecrosis/AVN (steroids/alcohol)• Severe pain but good ROM

• Monoarticular RA

• Monoarticular OA

• Prosthetic joint - loosening, # or infection

• Periarticular pathology

Is it an articular or extra-articular problem?

• ARTICULAR PERI-ARTICULAR

• pain all planes pain in plane of tendon• active = passive active < passive• capsular swelling/effusion linear swelling• joint line tenderness localised tenderness• diffuse erythema/heat localised erythema/heat

WHAT DO WE HAVE ?

Olecranon bursitis

42 YRS OLD MALE presents with pain, warmth, and swelling over his posterior elbow. The pt reports frequntly having to lean on his elbow while performing electrical work as part of his job. Although he is able to flex and extend the joint , flexion results in increased pain. After aspiration and cell count of the fluid obtained, which of the following is the minimum WBC count suggestive of infection ?

• WBC > 500 per mm3 .• WBC > 7,000 per mm3 • WBC > 10,000 per mm3 • WBC > 50,000 per mm3 • WBC > 100,000 per mm3

42 YRS OLD MALE presents with pain, warmth, and swelling over his posterior elbow. The pt reports frequntly having to lean on his elbow while performing electrical work as part of his job. Although he is able to flex and extend the joint , flexion results in increased pain. After aspiration and cell count of the fluid obtained, which of the following is the minimum WBC count suggestive of infection ?

• WBC > 500 per mm3 .• WBC > 7,000 per mm3 • WBC > 10,000 per mm3

• SEPTIC BURSITIS ACCOUNTS FOR 33% OF ALL OLECRANON BURSITIS .

What is the expected WBC counts in aspirated synovial fluid from a patient

with septic arthitis?

• It will be a turbid/purulent fluid, • USUALLY > 50,000 wbc/mm3 ( 5000-50,000)• > 75% PMN WBC

What is the expected WBC counts in aspirated synovial fluid from a patient

with septic arthitis?

A patient presents with acute polyarthritis. Joint fluid shows less than 10,000 WBCs, mostly lymphocytes. This is most consistent with __.

• rheumatoid arthritis• viral infection • gonococcal arthritis • systemic lupus erythematosus (SLE) • rheumatic fever

A patient presents with acute polyarthritis. Joint fluid shows less than 10,000 WBCs, mostly lymphocytes. This is most consistent with __.

• rheumatoid arthritis• viral infection • gonococcal arthritis • systemic lupus erythematosus (SLE) • rheumatic feverIn the other conditions, the WBC count is usually

higher, with predominantly PMNs.

Septic arthritis

• 15-30 per 100,000 population• Fatal in 11% of cases • Delayed or inadequate treatment leads to

irreversible joint damage

How do you get septic arthritis?

Pathogenesis

Who gets septic arthritis?

Who gets septic arthritis?

• common organisms Staphylococci or Streptococcus

• young adults, significant incidence gonococcal arthritis

• Elderly & immunocompromised gram -ve organisms

• Anaerobes more common with penetrating trauma

Who gets septic arthritis?• pre-existing joint disease

• prosthetic joints

• IV drug abuse, alcoholism

• diabetes, steroids, immunosuppression

• previous intra-articular steroid injection

What are the signs andsymptoms of septicarthritis?

Symptoms & signs of septic arthritis

• Typically hot, swollen, red tender joint with reduced range of movement, difficulty weight bearing

• Systemic upset• Night and rest pain • Symptoms usually present

for < 2/52 • Large joints more

commonly affected than small

• majority of joint sepsis in hip or knee

55 YRS OLD female with h/o RA presents with progressive swelling and pain in her knee for 6 days. She is on prednisone and states that her standard flares involve her ankles and fingers. Her vitals are normal ; afebrile . Examination reveals a moderate-sized knee effusion with warmth and tenderness and extreme pain on range of motion of the joint. Which of the following is the most appropriate next step in management ?

• Joint aspiration• MRI of the knee• Colchicine PO• Stress-dose steroids • Indomethacin PO

55 YRS OLD female with h/o RA presents with progressive swelling and pain in her knee for 6 days. She is on prednisone and states that her standard flares involve her ankles and fingers. Her vitals are normal ; afebrile . Examination reveals a moderate-sized knee effusion with warmth and tenderness and extreme pain on range of motion of the joint. Which of the following is the most appropriate next step in management ?

• Joint aspiration

Symptoms & signs of septic arthritis

• In pre-existing inflammatory joint disease symptoms in affected joint(s), out of proportion to disease activity in other joints.

• 10-15% of cases, > one joint - so polyarticular presentation does not exclude sepsis

• presence of fever not reliable indicator- if clinical suspicion high - treat

Kocher et al. 1999

• Hx of fever• Nonweightbearing• ESR >40mm/hr• WBC >12,000/mm3

What investigations are usefulin septic arthritis?

Investigations• Synovial fluid aspiration

– volume/viscosity/cellularity/ appearance

– gram stain/culture– Absence of organism does

not exclude septic arthritis– polarised light microscopy

(crystals)

– NB suspected prosthetic joint sepsis should ALWAYS be referred to orthopaedics

Investigations

• Always blood cultures • significant proportion blood cultures + ve in

absence of + ve synovial fluid cultures• FBC ESR & CRP• BUT absence of raised WBC, ESR or CRP Do not

exclude diagnosis of sepsis - if clinical suspicion high always treat

Other investigations• CRP useful for monitoring response to

treatment • Urate may be normal in acute gout and of no

diagnostic value in acute gout or sepsis • Measure urea, electrolytes & liver function for

end organ damage (poor prognostic feature)• Renal function may influence antibiotic choice

Other tests?

• If skin pustule is present, suggestive of gonococcal infection, then skin swab should be taken

• If history suggests possibility of genitourinary or respiratory tract infection then culture sputum (and CXR) & urine & take anogenital & throat swabs where appropriate

• If periarticular sepsis – appropriate swabs and cultures

Antibiotic treatment of septic arthritis

• Local and national guidelines

• Liaise with micro. guided by gram stain

• Conventionally given iv for 2 weeks or until signs improve, then orally for around 4 weeks

SEPTIC ARTHRITS: Oral Antibiotics

• Amoxicillin (25 mg/kg per dose administered every 6 hours)

• Cephalexin (37.5 mg/kg per dose administered every 6 hours)

• Clindamycin (13 mg/kg per dose administered every 8 hours)

• Cloxacillin (31 mg/kg per dose administered every 6 hours)

• Dicloxacillin (25 mg/kg per dose administered every 6 hours) Penicillin V (22 mg/kg per dose administered every 4 hours)

Arthrocentesis

• Critical diagnostic adjunct • Can be painless, safe, and simple when

performed correctly• Diagnostic or therapeutic

Indications

• Obtain joint fluid for analysis• Drain tense hemarthroses • Instill analgesics and anti-inflammatory agents• Prosthetic joints: only to rule out infection

Arthrocentesis

• Fat globules: diagnostic of fracture• Intraarticular morphine can provide relief for

up to 24 hours– 1 to 5 mg diluted in normal saline solution to a

total volume of 30 ml

Shoulder – Posterior Approach

Shoulder – Anterior Approach

Elbow – Lateral Approach

Flex elbow 90o

Prep skin

Insert needle in palpable bony

notch between lateral epicondyle

and olecranon

Elbow – Lateral Approach

Elbow – Posterior Approach

Wrist Approach

Wrist Approach

Wrist Approach

A patient has wrist inflammation that is too subtle to detect visually. It may best be detected by comparing __ to the opposite side.

• pronation

• supination

• flexion and extension

A patient has wrist inflammation that is too subtle to detect visually. It may best be detected by comparing __ to the opposite side.

• pronation

• supination

• flexion and extension

With even minimal inflammation, there will be a noticeable decrease in the flexion-extension range of motion

Knee – Lateral Approach

Knee – Lateral Approach

Extend knee, quadriceps and patella relaxed so patella can move mediolaterally. Needle into joint space just lateral to patella near its upper pole, parallel to the posterior (articular) surface.

Knee – Lateral Approach

Knee – Medial Approach

Knee – Medial Approach

Knee – Medial Approach

Knee – Medial Approach

Knee – Medial Approach

AnklePalpate the medial and lateral malleoli with your thumb and index finger. The joint space is located one to one and a half cm above the line joining the tips of the malleoli.

AnklePalpate the dorsalis pedis artery and choose a puncture site anywhere on the anterior aspect of the ankle, avoiding the dorsalis pedis artery.

Ankle – Lateral Approach

Ankle – Medial Approach

Synovial Fluid Analysis

• Identify crystals, pus • Analyze color, clarity, cell count, differential,

Gram’s stain, crystals• Positive Gram’s stain: diagnostic for septic

arthritis• Negative Gram’s stain: does not rule out

septic arthritis

Synovial Fluid Cell Count

• Noninflammatory vs. inflammatory• ED wet mount prep

– 1 to 2 WBCs per high-power field consistent with noninflammatory

– >20 WBC/HPF suggests inflammation or infection

• Septic: >50,000 WBC/mm3 (also rheumatoid, gout, pseudogout)

NormalNormalNon-Non-

inflammatoryinflammatory InflammatoryInflammatory InfectiousInfectious

Trans-Trans-parentparent TransparentTransparent CloudyCloudy Cloudy Cloudy

ClearClear YellowYellow YellowYellow Yellow Yellow

<200<200 <2000<2000 200 – 50,000200 – 50,000 >50,000>50,000

<25%<25% <25%<25% >50%>50% >50%>50%

NegativeNegative NegativeNegative NegativeNegative Positive Positive

Appear-Appear-anceance

ClarityClarity

WBCsWBCs

PMNsPMNs

CultureCulture

Synovial Fluid Analysis

Septic arthritis: SMS

• with a short history of a hot, swollen, tender joint (or joints) plus restriction of movement; septic arthritis until proven otherwise

• If clinical suspicion high investigate & treat as septic arthritis even in absence of fever

gout

Gout• Caused by monosodium urate crystals• Most common type of inflammatory monoarthritis• Typically: first MTP joint, ankle, midfoot, knee• Pain very severe; cannot stand bed sheet• May be with fever and mimic infection• The cutaneous erythema may extend beyond the

joint and resemble bacterial cellulitis

Acute Gouty Arthritis

Risk Factors• Primary gout: Obesity, hyperlipidemia,

diabetes mellitus, hypertension, and atherosclerosis.

• Secondary gout: alcoholism, drug therapy (diuretics, cytotoxics), myeloproliferative disorders, chronic renal failure.

Microscopic appearance of the crystals of gout include all of the following EXCEPT:

• needle-shaped urate crystals• positively birefringent • negatively birefringent• Non of the above

Microscopic appearance of the crystals of gout include all of the following EXCEPT:

• needle-shaped urate crystals• positively birefringent

Urate Crystals

• Needle-shaped

• Strongly negative birefringent

CPPD Crystals Deposition Disease

• Can cause monoarthritis clinically indistinguishable from gout – hence called Pseudogout.

• Often precipitated by illness or surgery.• Pseudogout is most common in the knee (50%) and

wrist.• Reported in any joint (Including MTP).• CPPD disease may be asymptomatic (deposition of

CPP in cartilage).

Associated Conditions• Hyperparathyroidism• Hypercalcemia• Hypocalciuria• Hemochromatosis• Hypothyroidism• Gout• Aging

CPPD Crystals

• Rod or rhomboid-shaped

• positive birefringent

THANK-YOU