Pyogenic Infections

Question 1

first signs of pyogenic osteomyelitis inf

Answer 1

Soft tissue swelling (bone takes 10 day latency)

Question 2

x ray signs of pygogenic osteomyelitis

Answer 2

• Blured mm/fat interface
• moth eaten or permeative bone destruction (usually metaphysics)
• Laminated/codmans triangle periosteal rxn

Question 3

In subacute pyogenic osteomyelitis what signs will you see

-timeframe

Answer 3

• More extensive bone destruction (lytic/ cortical destruction)
• <3m
• more insidious onset usually

Question 4

What are the 3 signs of chronic osteomyelitis

Answer 4

Sequestrum- segment of necrotic bone (lytic destriction w thick collar around it)

Involucrum- collar of living bone surrounding the sequestered bone(linear piece of bone that sclerotic)

Cloaca- A defect in invilucrum wuch allows drainage(may look like lucent dot)

Question 5

What is marjolins ulcer

Answer 5

When cloaca drains into soft tissue

• slow growing painless mass
• develops in area of chronic wounds

Question 6

Bone appearence of pyogenic oteomyelitis

Answer 6

Moth eaten lytic destriction, osteoporotic and areas of sclerosis
-May see involucrum, sequestrum

Question 7

Where will you see bone expansion in chronic pyogenic osteomyelitis

Answer 7

Bone expansion in the mid to distal diaphysis

Question 8

Imaging findings of early and late chronic osteomyelitis

Answer 8

Early (days-weeks)- Soft tissue, periosteal rxn, subtle permiative bone destruction

Late (months)- Large moth eaten patten, periosteal rxn becomes thick, Look for cloaca etc

Question 9

What is broadies abscess + pres

Answer 9

a localized form of suppurative osteomyelitis (doesnt expand along bone)

-Radiolucent nidus >1cm

Question 10

Symptoms of brodies abscess

Answer 10

Osteoid osteoma like symptoms with night pain relieved by asprin

Question 11

Mc sight of brodies abscess

Answer 11

Tibia

Question 12

How early will symptoms be present on MRI for septic arthritis

Answer 12

Findings usually evident with 24hrs following onset

Question 13

What signs on MRI will you see for septic arthritis

Answer 13

Synovial enhancement, perisynovial edema + joint effusion

Low signal on T1, high on T2

Question 14

How long is the lateny period to see infection in spine

Answer 14

21 days

Question 15

first sign of pyogenic infection in spine

Answer 15

Disc space narrowing

Question 16

What signs will you see in pyogenic infection of spine

Answer 16

• Monoarticular lvl
• disc space narrowing
• endplate destruction
• altered alignment

Question 17

What is an early sign of septic arthritis

Answer 17

-Distension of the Jt capsul (waldenstrons signs)

Question 18

What teardrop distance is indicative of early septic arthris in hip

Answer 18

greater than 11mm or >2mm more than CL side

Question 19

What will u see un late septic arthritis of hip

Answer 19

• rapid progrss of moth eaten destuction all around jt
• rapid narrowing of the jt spaces
• Potential for AVN
• Sequestration etc.

Question 20

Location of toms smiths arthritis (3)

Answer 20

Bones w the metaphysis within the jt capsul

• prox/distal femur
• distal tib
• prox/distal humerus

Question 21

Who is susseptible to tom smith arthritis

Answer 21

kids susseptivle as normally open growth palate inhibits spread but infection is in synovial fluid so can bypass