2. Definition
Inflammation of a synovial membrane
with purulent effusion into the joint
capsule, often due to bacterial
infection
3. Cont…
SA is considered as a rheumatologic
emergency as joint destruction occurs
rapidly and can lead to significant
morbidity and mortality.
Although accurate diagnosis could be
particularly challenging especially in
patients with an underlying
inflammatory joint disease.
4. Pathophysiology
Once the bacteria or any other
causative agents sets in, there is rapid
bacterial replication in the joint
resulting in an ensuing inflammatory
process that can lead to rapid local
joint destruction and might be
accompanied with a systemic
infection.
5.
6. Aetiology
SA is caused by the invasion of bacteria, viruses, or fungi into
the synovial membrane of a joint.
Staphylococcus aureus - the most common cause in
adults. Has a specific affinity of synovial structures.
Streptococci- the second most common cause
Haemophilus influenzae - was the most common cause in
children but is now uncommon in areas where Haemophilus
vaccination is practiced
Neisseria gonorrhoea- in young adults, multiple macules or
vesicles seen over the trunk are a pathognomonic feature.
Escherichia coli- in the elderly, IV drug users and the
seriously ill
M. tuberculosis, Salmonella
This occurs most commonly by direct inoculation, penetrating
wound, or direct extension. The most common mechanism of
infection is via haematogenous.
7. Cont…
Viruses that can cause septic arthritis
include hepatitis A, B, and C ,
herpes viruses, HIV&AIDS virus,
mumps and ebola.
Fungi that can cause septic arthritis
include cistoplasma, coccidioides,
and Blastomyces.
9. Frequency
2-10 cases per 100,000 in the general
population
30-70 cases per 100,000 in patients
with immunological disorders or
deficiencies, and joint replacements
Gonococcal: women 3x > men
10. Risk factors
While joint infection occasionally affects
people with no known predisposing risk
factors, it more commonly occurs when
certain risk situations are present which
includes~
Abnormal joint architecture is the most
important risk factor for SA e.g. in pts
with RA
For reasons that are not entirely clear,
the risk of SA in a patient with RA is
increased 4- to15-fold irrespective of
therapy
11. cont…
surgery
IV drug use
Risk for sexually transmitted disease
Anaemia
Diabetes
Age
Alcoholism
Malignancy
medications
12. Root of infection:
◦ Blood stream
◦ Contiguous infection
◦ Direct inoculation:
Injection: 0.0002
Arthroscopic surgery: < 0.005
Animal or human bite
17. Site of involvement:
Knee: 55%
Ankle: 10%
Wrist: 9%
Shoulder: 7%
Hip: 5%
Elbow: 5%
SC: 5%- IV drug abuser
SI: 2%- IV drug abuser
Foot joints: 2%
18. Diagnostic features
A case definition for bacterial SA was
proposed by Newman which required
one of four points to be met:
(1) isolation of an organism from an
affected joint
(2) isolation of an organism from
another source with a concomitant
swollen, hot joint
19. Cont…
Arthrocentesis with synovial fluid
examination and culture
Increased White blood cell count
Increased Erythrocyte sedimentation rate
(ESR)
Increased Temperature
Increased C-Reactive Protein (CRP)
Imaging studies are used to rule out
other conditions
Blood cultures
20. Cont…
(3) clinical features and turbid joint fluid
in the presence of previous antibiotic
therapy
(4) Histologic or radiologic evidence
consistent with septic arthritis
21. Radiography
Early:
◦ Soft tissue swelling Joint space widening
Late (2-3 w):
◦ Erosion
◦ Joint space narrowing
22.
23. Clinical features
Is summarised as a red, hot painful joint
Fever (toxic)
Erythema
Sever pain
Sever swelling of one joint
Sever tenderness
Warmth
Sever limited ROM
24. cont….
SA presents with a short 1–2 week
history of pain, swelling, heat and
restricted movement in the affected
joint(s)
There is a common misconception
that
SA affects only one joint but evidence
now suggests that in up to 22% of
cases the presentation is polyarticular
25. Symptoms in
Newborns/Infants
Inability to move the limb
(pseudoparalysis)
Cries when infected joint is moved
Fever
Unable to move the limb
Irritability
26. Cont….
If the hip joint is infected the child
holds the hip rigidly in a flexed,
abducted and externally rotated
position that maximizes capsular
volume.
27.
28. Medical management
Antibiotics
Current antibiotic choices should be made
based due to what likely organism and
subsequently modified in light of culture and
sensitivity results.
NSAIDS
An overactive immune response, secondary to
the initial septic
Event causes more joint damage and that
steroid treatment down regulates this
exaggerated native immune response.
Disease modifying anti rheumatic drugs
29. Cont…
Arthroscopy- this is a process of
extracting joint fluid/pus through the
means of a small incision and suction
tubes placed around the joint.
Arthrocentesis-a needle is placed into
the joint to extract ad remove the joint
fluid.
Amputation may be done but rare
33. Physiotherapy management
Primary aims
Reduce pain
Restore and maintain physiological
function
Patient education about exercise and
management of their condition.
34. Cont…
Immobilization
control pain as it is often too painful to
bear weight.
Mobilization can begin if the patient is
responding well following 5 days of
gentle treatment. PT needs to consists
of allowing the joint to be in its
functional position and positioning the
joint to allow passive range of motion
activities.
35. Cont….
Electrotherapy-ice
hydrotherapy, heat and TENS, IFT,
Ultrasound to manage pain and joint
stiffness.
NB: heat modalities are not supposed
to be used in the acute phase or
before initiation of antibiotic treatment.
36. Complications of SA
Rapid clearing of the infection is
critical to preserve the joint. If the
infection has been longstanding, the
possibility of joint destruction exists.
The keys to successful outcome are
rapid medical attention and drainage
and the accurate administration of
antibiotics to which the offending
microbes are susceptible.
37. Prognosis
The best outcome for individuals with
septic arthritis is immediate treatment.
Mortality ranges from 19-25%
permanent joint disability occurs in 25-
50% of the cases.
Fifty percent of adults with septic
arthritis have significant decreased
ROM or chronic pain after the
infection.
38. Cont…
Poor outcome predictors in prognosis
of septic arthritis include the following:
Age older than 60, infection of the hip
or shoulder joints, underlying
rheumatoid arthritis, positive findings
on synovial fluid cultures after 7 days
of therapy, delay of 7 days or longer in
beginning treatment
39. REFERENCES
Septic Arthritis Aspiration Techniques
and Indications for Surgery at
Medscape. Author: Nadera Sweiss.
Updated: Feb 7, 2012
Prosthetic Joint Infectious Arthritis:
Infections of Joints and Bones: Merck
Manual Professional [Internet]. [cited
2010 Feb 16];Available
Klippel, J.H., et al. Primer on the
Rheumatic Diseases. New York:
Springer, 2008.
40. Cont…
Weston VC, Jones AC, Bradbury N, et
al. Clinical features and outcome of
septic arthritis in a single UK Health
District 1982–1991. Ann Rheum
Dis1999; 58:214–219.