Septic Arthritis - arthrotomy and debridement
Septic arthritis word is a misnomer as
initially there is only infection of joint and if not treated early than
Arthritis (joint destruction) develops. Thus all sepsis of joints do not
cause arthritis only inadequately treated ones do.
Etiology and Pathology
∙ The hematogenous route of infection is the most common route
in all age groups.
Epidemiology
∙ S. aureus – is the most common organism.
(Absent movements of a joint after ruling out trauma in
pediatric population is septic arthritis till proved otherwise).
Diagnosis: X-rays are usually normal or may indicate soft
tissue swellings, MRI may show effusion, synovitis or cartilage
destruction and aspiration of joint will help to confirm the
diagnosis by culture and sensitivity and can also help to
differentiate from transient synovitis. Aspiration also decreases intra-articular pressure and reduces chances of Avascular
necrosis (AVN) of femoral head.
Procedure:(Medscape)
Joint Fluid Analysis and Culture
Always perform joint aspiration under the most sterile conditions possible to prevent the introduction of infection.
Normal joint fluid is clear and colorless and produces a stringlike structure when ejected from a syringe, indicating normal viscosity. Infected joint fluid is typically yellow-green due to elevated levels of nucleated cells, and the cell count is usually markedly elevated, demonstrating a predominance of polymorphonuclear leukocytes
Aspiration shows > 50,000 cells/mL and > 75% polymorpho�neutrophils in septic arthritis.
∙ Culture of the aspirate is the gold standard for diagnosis.
Septic arthritis with negative cultures – Diagnostic Criterion
(Morrey and associates criterion)
5 out of 6 must be present
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38.3 degree C temperature
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Swelling of suspected joint
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Pain in joint that increases with movement.
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Systemic symptoms
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No other pathologic process
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Satisfactory response to antibiotics therapy