18- Septic Arthritis

Question 1

Suppurative Appendicular
General information
31 reader
1392 txt

Answer 1

General Information:
− organisms enter from direct implantation, blood or extension from adjacent bone
infection
− synovial involvement –> capsular distention –> cartilage death and destruction
− loss of cartilage causes joint destruction and bone involvement
− most common organism: staph. aureus
− usually monoarticular
− most common joints involved: knee, hip

Question 2

What are the clinical features of suppurative- Appendicular Septic Arthritis
31 reader

Answer 2

-decreased range of motion due to pain and capsula edema
-may see fever, chills, erythema (is redness of the skin or mucous membranes, caused by hyperemia of superficial capillaries)
− labs show elevated ESR, leukocytosis and + culture

Question 3

What are the radiological findings of suppurative- appendicular septic arthritis?
32
1392

Answer 3

−

Note: changes occur rapidly compared to other inflammatory processes (days instead of months/years)
A. Soft tissue
− distention of capsule
− widening of the joint space early on (particularly in kids), loss of space in a few
weeks
B. Osseous/Articular
− periarticular osteopenia
− irregular subchondral bone destruction
− rapid loss of joint space
− osseous ankylosis of the affected joint (rare)

Question 4

What is the incidence of Suppurative spinal Septic arthritis?
32
1392

Answer 4

I. Incidence
− only 2-4% of skeletal infections involve the spine
− the lumbar spine is the most common region affected − staph. aureus is the most common organism

Question 5

What is the clinical features of suppurative spinal septic arthritis?
32
1392

Answer 5

− may find a history of previous visceral infection or surgery
− insidious onset of back pain is the m.c. complaint; may be radicular
− fever is an uncommon finding, so clinical presentation may be misleading

Question 6

What are the radiographic features of suppurative spinal septic arthritis?

Answer 6

− avasculardiscprotectsjointinitially
− latent period for osseous changes is 21 days
− Infection occurs at ant. aspect of body, spreads along endplate => endplate
irregularity/destruction, body destruction, disc height loss − mayseeparaspinallinedisplacementfromedema/abscess − may see epidural abscess and cord compression
− SI joint involvement presents as unilateral sacroiliitis

A. Scintigraphy
− technetium, gallium, and indium are used − look for hot spot
B. MRI
− sensitive
− helpful in identifying extent of lesion and soft tissue involvement − low signal on T1, high on T2

Question 7

what is the treatment of suppurative spinal septic arthritis?

Answer 7

− Antibiotic therapy, usually intravenous

Question 8

Non-Suppurative general info

33

Answer 8

f