Emergency Medicine

ACUTE ARTHROPATHY

106 General Medical Emergencies

3 Check temperature, pulse and blood pressure. There is localized joint pain,

warmth, erythema and severely restricted range of active and passive

movement, but with a less precipitate onset than with gout.

4 Send blood for two sets of blood cultures, FBC, ESR and C-reactive protein

(CR P).

5 Request an X-ray which will initially be normal, but subsequently may show

destruction of bone with loss of the joint space.

6 Or arrange an ultrasound scan, which is most helpful in demonstrating an

effusion in joints such as the hip (see p. 370), or even a CT scan for the sterno-

clavicular joint.

MANAGEMENT

1 Give an analgesic such as paracetamol 500 mg and codeine phosphate 8 mg

two tablets orally.

2 Refer the patient immediately to the orthopaedic team for joint aspiration

under sterile conditions, i.v. antibiotics, rest and repeated operative drain-

age.

(i) Joint aspiration should yield turbid, yellow fluid with a

polymorph WCC >50 000/ mL. A fluid culture is positive in

>50%.

Gouty arthritis

DIAGNOSIS

1 Gout is much more common in men, and is associated with diabetes, hyper-

tension, hypercholesterolaemia and myeloproliferative disease (especially

following treatment), renal failure (cause or effect), thiazide diuretic therapy,

or dietary excess, alcohol and trauma.

2 It is commonest in the metatarsophalangeal joint of the great toe or in the

ankle, wrist and knee, sometimes with a precipitate onset waking the patient

from sleep.

3 Chronic cases may be associated with gouty tophi on the ear and around the

joints, polyarthropathy and recurrent acute attacks.

4 The patient may be mildly pyrexial with a red, shiny ‘angry’ joint.

5 Send blood for FBC, ELFTs, and ESR plus CRP if septic arthritis is as likely.

(i) Laboratory blood results may show a mild leucocytosis, with a

raised uric acid level (>0.4 mmol/L), but the serum uric acid may

be normal in up to 40% of acute attacks.

6 Definitive diagnosis is by joint aspiration and polarizing light microscopy

showing strongly negative birefringent crystals.

(i) Joint aspiration yields cloudy yellow fluid, with a WCC of

2000–50 000/mL. Polarizing microscopy is diagnostic.