Musculoskeletal Infection Flashcards
1
Q
What image modality is this and what condition do these findings demonstrate?
A
Sagittal MRI - Spondylitis Tuberculosis
2
Q
- Diffuse infection of a muscle or muscle group
- Present with short history of fever and localized pain with passive movement of the muscle
- Staphylococcus aureus is most common organism
- Clostridial myonecrosis is an acute life-threatening form with surgical debridement often the only chance for survival
A
Pyomositis
3
Q
What are the findings and differentials for this image?
A
4
Q
What condition is shown here?
A
Cellulitis
(Soft tissue emphysema; could also be result of trauma)
5
Q
Ultrasound, MRI and CT are useful in evaluation & differentiating with _____
A
Osteomyelitis
6
Q
Suppurative Osteomyelitis in what age group?
- More insidious onset
- Local signs of inflammation, systemic signs of infection
- Common organisms: Staph aureus, pseudomonas, Klebsiella)
A
Adult (16+)
7
Q
What is likely cause of these findings?
A
Suppurative Osteomyelitis
(Involucrum, cortical destruction)
8
Q
What are these findings associated with?
A
Pathologic fracture secondary to Suppurative Osteomyelitis
(posterior angulation of segment, increased soft tissues)
9
Q
Infection of periosteum =
A
Periostitis
10
Q
What modality is used in his image & what condition is demonstrated?
A
Ultrasound
Cellulitis
11
Q
What are the findings and differentials for this image?
A
12
Q
What is likely the cause of these findings?
A
Infectious Spondylitis (Suppurative)
(ill-defined endplates, periarticular osteopenia of endplates)
13
Q
In _____, hemtogenous spread in long bones of suppurative osteomyelitis occurs when:
- Vessels penetrate the closed growth plate
- Epiphyseal & metaphyseal region can be involved, as well as joint
- Joint involvement secondary to osteomyelitis is more common in this age group because of this
A
Adult (16+)
14
Q
- Solid infected and inflamed tissue with intact blood supply, may progress to abscess
- MRI and or ultrasound can help differentiate with abscess
A
Phlegmon
15
Q
Infection in a joint space =
A
Septic Arthritis
16
Q
- Result of subacute or chornic osteomyelitis
- Sharply outline focus of burned out infection, may be sterile or contain residual Staph organism
- See oval or serpiginous lucency greater than 1cm in diameter & a variable zone of surrounding reactive sclerosis
- Likes distal tibia and knee
A
Brodies Abscess
17
Q
Organisms causing septic arthritis enter in what means
A
Direct implantation
Hematogenous route
Extension from adjacent bone infection
18
Q
What condition results in these findings?
A
Cellulitis
(Increased soft tissue, effusion, small vessel calcification; patient likely diabetic)
19
Q
_____ is most common in lower extermity (hip & knee, spreads to these locations by traveling along psoas)
- initial infetion starts in metaphysis then spreads to joint
- Changes primarily joint related w/ adjacent bone destruction
- May result in fibrous ankylosis
A
Tuberculous Arthritis
20
Q
____ is most common level involved in infectious spondylitis - non-supurrative
A
L1
21
Q
Subligamentous spread is more common and may lead to anterior vertebral body erosio, psoas (cold) abscess, additional joint involvement (most common joint affected = hip)
= what condition
A
Infectious Spondylitis - Non-Suppurative
22
Q
What are the findings and differentials for this image?
A
23
Q
Acute ____ will demonstrate rapid destruction of bone
- 10 day laten period on x-ray
- Permeative or moth-eaten pattern of bone destruction
- Solid or laminated periosteal reaction
A
Suppurative Osteomyelitis
24
Q
What is shown here?
A
Sacroilitis - Septic Arthritis
(Loss of joint space; monoarticular inflammatory arthritis → think infection)
25
What condition results in these findings?
Septic Arthritis
(Periarticular osteopenia, destruction of femoacetabular joint)
26
Suppurative Osteomyelitis in what age group?
- Males most commonly affected
- Acute onset of symptoms
- Local signs of inflammation, systemic signs of infection
- Common organisms: Staph aureus, salmonella
Childhood (1-16 yrs)
27
What imaging modality & condition is shown here?
Coronal MRI
Suppurative Osteomyelitis; abscess
28
This is an example of suppurative osteomyelitis via \_\_\_\_\_
Direct Implantation
29
What imaging modality & what condition is shown here?
MRI (T1 w/ contrast) - Suppurative Osteomyelitis
30
- Rapidly destructive infection along fascial planes
- Most often polymicrobial
- Solitary infection with Group A Streptococcal and Clostridium species may also be responsible
- Typically life-threatening requiring emergency surgery
- Diabetics at particular risk owing to immunocompromised and vascular insufficiency
Necrotizing fasciitis
31
In adults, _____ will appear as:
- Often wont show osseous changes until 21 days
- Infection occurs at anterior corners of body & spreads to endplate → endplate irregularity/destruction, disc height loss
- - May see paraspinal line displacement from edema/abscess/phlegmon
- May see epidural abscess causing cord compression
- SI joint involvement presents as unilateral sacroilitis
Infectious Spondylitis (Suppurative)
32
This is an example of
Involucrum (Suppurative Osteomyelitis)
33
What is this photo demonstrating?
Septic Arthritis
34
What region of the spine is most likely to be affected by infectious spondylitis (aka spondylodiskitis)
Lumbar
35
- Living bone (periosteal reaction) that forms around necrotic bone (sequestrum) and attems to wall off the infection
- Seen in Suppurative Osteomyelitis
Involucrum
36
This is an example of what condition
Suppurative Osteomyelitis (Direct implantation or post-op)
37
Most common route of spread in Suppurative Osteomyelitis is _____ but can also be contiguous (direct spread from another site of infection), direct implantation or post-op
Hematogenous
38
- Infection centered along fascial planes
- Serious condition often requiring surgical debridement
Fasciitis
39
Infection of the cortex =
Osteitis
40
What is likely the cause of these findings?
Suppurative Osteomyelitis (Permeative/motheaten)
41
- Acute inflammatory response due to infection of the cutaneous and subcutaneous tissues
- Most commonly due to Staphylococcus aureus and less commonly Streptococcus pyogenes
- Usual route of infection is direct implantation
Cellulitis
42
Infection of bone marrow =
Osteomyelitis
43
The following radiographic changes are associated with \_\_\_\_\_:
- Soft tissue changes within 3 days of bone infection
- Localized swlling & fat plane displacement
- Blurring of fat/muscle interface
- May see soft tissue emphysema (gas)
- Phlegmon, soft tissue abscess
- Sinus tracts (hole in tissues)
Suppurative Osteomyelitis
44
What are the findings and differentials for this image?
45
What are the findings and differentials for this image?
46
What are the findings and diagnosis for this image?
47
What are the findings and diagnosis for this image?
48
- Can occur as a result of a variety of soft tissue infections
- Staphylococcus aureus is most common organism
- Can mimic necrotic tumors on imaging
Abcess
49
This is demonstrating the progression of
Suppurative Osteomyelitis
| (Sequestrum in 5 months)
50
What are the findings and differentials for this image?
51
Phemister's triad consists of:
- Juxta-articular osteoporosis
- Articular erosions
- The key is maintained joint space until late in the disease process
This is associated with \_\_\_\_\_
Tuberculous Arthritis
52
What condition would result in these findings?
Tuberculous Arthritis
(Marginal erosion, juxta-articular osteopenia)
53
Joint aspiration & culture is needed for definitive diagnosis of \_\_\_\_\_
Septic Arthritis
54
What are the findings and differentials for this image?
55
What is shown here?
Sequestration (Suppurative Osteomyelitis)
(CT on right)
56
In this Axial CT of cervical spine, what is demonstrated?
Sequestration (Suppurative Osteomyelitis)
57
What are the findings and differentials for this image?
58
What type of study is shown here?
Coronal CT
59
In \_\_\_\_\_, hemtogenous spread in long bones of suppurative osteomyelitis occurs when:
- Vessels perforate open growth plate
- Epiphysis or metaphysis can be affected, as well as joint
Infantile (0-1 years)
60
What is the likely cause of these findings?
Infectious Spondylitis (Suppurative) - with increased retrotracheal space
(complete loss of disc height w/ endplate destruction, gapping of facet joint/widening of interspinous face, calcifications on anterior)
61
What are the findings and differentials for this image?
62
What are the findings and differentials for this image?
63
What is likely the cause of these findings?
Infectious Spondylitis (Suppurative) - Deviated paraspinal lines
(Could also be a result of trauma, tumor, etc.)
64
What are the findings and differentials for this image?
65
- Usually due to tuberculosis or less often fungal infections
- Less common
- Course is insidious
- Insidious back pain, decreased motion & tenderness in spine
- Joint swelling, increased temp, muscle atrophy seen in extremities
Infectious Spondylitis - Non-Suppurative
66
What are the findings and differentials for this image?
67
- Cortical and/or periosteal defect which allows draining of pus out of bone
- Seen in Suppurative Osteomyelitis
Cloaca
68
What are the findings and diagnosis for this image?
69
What is a definitive diagnosis based on these findings?
Tuberculosis Spondylitis
| (Tear-drop shaped cold abscesses)
70
Changes in ____ occur rapidly compared to other inflammatory arthritis
- Distension of capsule
- Widening of joint space early on, loss of space in a few weeks
Septic Arthritis
71
In \_\_\_\_\_, hemtogenous spread in long bones of suppurative osteomyelitis occurs when:
- Metaphysis is most common site of origin
- Vessels dont penetrate growth plate and blood flow is sluggish
Childhood (1-16 yrs)
72
Bacterial Osteomyelitis = ____ osteomyelitis
Tuberculosis or Fungal infections = ____ osteomyelitis
Suppurative
Nonsuppurative
73
Suppurative Osteomyelitis in what age group?
- Commonly multi-focal
- Pain & swelling in region of infection
- Unwilling to move affected bone
- Common organisms: Strep Group B, Staph aureus, E. coli
Infantile (0-1 yrs)
74
What are the findings and differentials for this image?
75
What is shown here?
Septic Arthritis
76
What is shown here?
Brodies Abscess
77
Cloaca (Suppurative Osteomyelitis)
(Irregular cortical thickening & trabeculae patterns, lucent channel that goes into round defined lucency)
78
What deformity is this and what condition is it associated with?
Gibbus - associated with Tuberculosis Spondylitis (but can occur with other conditions)
79
What is shown here?
Cloaca in an involucrum (suppurative osteomyelitis)
80
What modality & condition is demonstrated here?
Sagittal MRI of CS/TS spine
Infectious Spondylitis (Suppurative)
81
What is likely the cause of these findings?
Tuberculosis Spondylitis (cannot neccessarily differentiate from other infection w/o hx)
Differentiate between suppurative vs. non-suppurative you need clinical hx
82
What condition is likely shown here?
Suppurative Osteomyelitis
83
\_\_\_\_\_ is the most common organism that causes septic arthritis
\_\_\_\_\_ is more common in IV drug users
Staph Aureus
Pseudomonas aeruginosa
84
Clinical prevention of _____ includes:
- Redness and swelling of the affect limb with pain
- Fever and general systemic feeling of unwellness are common
- Spread in a progressive fashion possibly resulting in redlines following the lymphatic tracks
Cellulitis
85
\_\_\_\_\_ is most common organism to cause infections spondylitis - suppurative
Staph aureus
86
In children, ______ will show up as:
- Loss of disc height
- Secondary endplate & vertebral body destruction
- May see paraspinal line displacement from edema/abscess/phlegmon
Infectious spondylitis (suppurative)
87
What are the differentials & treatment for Brodies Abscess?
Osteoid osteoma, osteoblastoma
Surgical decompression & curettage
88
This is demonstrating a treatment for what condition?
Suppurative Osteomyelitis - Antibiotic beads
89
\_\_\_\_\_\_ is more common in skeletal immature individuals in appendicular skeleton (lower extremity, femur & tibia most commonly affected)
- Males: Females = 3:1
- Peak age range = 2-12 years
- 90% due to staph aureus
Suppurative osteomyelitis
90
Tuberculosis spondylitis is going to result in _____ deformity eventually
Kyphotic
91
Radiologic findings of ____ include:
- Periarticular osteopenia
- Erosions
- Subchondral bone destruction
- Osseous ankylosis of affect joint late (rare)
Septic Arthritis
92
- Fragment of infected necrotic bone, no blood supply
- Forms in chronic osteomyelitis
Sequestrum
93
What are the findings and differentials for this image?
94
What condition is shown here?
Septic Arthritis
(increased soft tissue size & erosions of joint)
95
Clinical features of ____ include:
- Decreased ROM due to pain and capsular edema
- May see fever, chills, erythema
- Labs show elevated ESR, leukocytes & positive culture
Septic Arthritis
96
What is likely the cause of these findings?
Suppurative Osteomyelitis
(Permeative/motheaten, possible cortical destruction, laminated/solid periosteal reaction)
97
What are the findings and differentials for this image?
98
What are the findings and differentials for this image?
99
What modality of imaging & what condition is shown here?
Coronal CT
Suppurative Osteomyelitis w/ sequestrum
100
What are the findings and diagnosis for this image?
