9 - Arthrography and Tenography Flashcards Preview

Clinical Pod Med Exam 1 > 9 - Arthrography and Tenography > Flashcards

Flashcards in 9 - Arthrography and Tenography Deck (24)
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1
Q

Arthrography

A

Uses contrast injected into a joint to demonstrate abnormalities not evident on radiographs

First you inject it into the joint, then you take an x-ray

2
Q

Contrast types

A

Positive contrast

  • Iodinated radiopaque material
  • The concern with this is an iodine allergy (ask about shellfish allergy***)
  • If they are allergic to shellfish/iodine, you can do a negative contrast

Negative contrast

  • Inject air into the joint instead
  • It isn’t going to kill them (contrary to popular belief)

THIS IS IMPORTANT

Know the reason why you use one or the other (shellfish allergy)

3
Q

Most common joint for arthrography

A

Ankle

4
Q

Indications for ankle arthrography

A
  • Soft tissue trauma (ligamentous tear, injury to joint capsule)
  • Osteochondaral defects
  • Loose bodies
5
Q

Technique for ankle arthrography

A
  • Inject lidocaine over site
  • Sterile betadine prep and sterile technique
  • Enter ankle with a 23 gauge needle just medial to the tibialis anterior tendon
  • Inject 8-10 cc of contrast material
  • Passive ROM of ankle
  • Examine under fluroscopy

Don’t want them to get a septic joint or an infected joint, so you need to use sterile betadine prep to avoid introducing bacteria

The easiest place to enter the ankle joint is just medial to the tibialis anterior tendon

You inject until you feel back pressure… Bigger people will take more contrast, smaller people will take less contrast (based on size) - this is the “maximum content” of the joint = “INSUFLATE” the joint = buzz word ***

After injecting contrast, do some passive ROM of the ankle to distribute the contrast before doing to fluroscopy or x-ray

6
Q

Study on quantifying normal ankle joint volume on cadavers

A
  • Level 5 cadaveric study
  • Examined 9 cadavers and injected 2 mL of contrast in ankle
  • Mean maximum joint volume was 20.9 mL with a range of 16-19 mL
  • Don’t want to put too much in though (stick to 8-10 mL) because you can burst the joint capsule
7
Q

Normal arthrography findings

A
  • Anterior and posterior recesses of the joint fill with contrast and will be smooth
  • Contrast can extend 1 cm above joint surface and distally to talar head and neck
  • Contrast may extend between tibia and fibula 2.5 cm above ankle
  • Communication to posterior STJ: 10%
  • Contrast along needle tract

You are looking for SMOOTH delineation

When there is a rupture in the capsule and there is leak out, you will see the contrast running everywhere

8
Q

Abnormal arthrography findings

A
  • Extravasation of contrast beyond the confines of the joint

- CFL tear with contrast in the peroneal tendon sheath

9
Q

What is the “buzz word” when looking at an abnormal arthrography?

A

EXTRAVASAION

- Contrast found outside of the joint capsule

10
Q

CFL tear

A
  • Can see contrast in the peroneal tendon sheath
  • You shouldn’t be able to inject contrast in the joint on the medial ankle and have it flow up the tendon sheath on the lateral side of the ankle

ABNORMAL = contrast found in the peroneal tendon sheath (slide 15)

11
Q

Most common joint for arthrography and other joints that can be used

A

Ankle is the MOST common
- Very easy and convenient due to size

Second most common is the second MPJ or even the first MPJ

Other joints are harder to enter and do NOT have a well defined capsule

12
Q

How common with arthrography be used?

A

15 or 20 of us will be questioned about arthrography on board exams or during residency

Only 2 of us will actually do this

13
Q

Tenography

A

Uses contrast injected into tendon sheaths to diagnose inflammatory or posttraumatic conditions

14
Q

Does every tendon have a tendon sheath?

A

Every tendon does NOT have a tendon sheath

If a tendon changes direction or angle, it DOES have a sheath

If a tendon has a straight trajectory, it does NOT have a tendon sheath (Achilles)

15
Q

What is harder to do, a tenogram or a arthrogram?

A

Tenogram

16
Q

Tenogram technique

A
  • More difficult than an arthrogram

- Same general technique as an arthrogram

17
Q

Lateral group tenogram technique

A

Peroneus Longus and Brevis

18
Q

Medial group tenogram technique

A
  • Tibialis Posterior

- FDL and FHL (flexor tendons)

19
Q

Anterior group tenogram technique

A
  • Tibialis Anterior

- EDL and EHL (extensor tendons)

20
Q

Just an FYI…

A

I am NOT going to ask you the anatomical location to inject a specific muscle group or tenogram

This is what’s coming…

21
Q

Where would you inject for the lateral group?

A

Sheath entered posterior and proximal to the lateral malleolus

Not on exam

22
Q

Where would you inject for the medial group?

A
  • Tibialis posterior entered just medial and posterior to the distal tibial metaphysis about 3-4 cm above the ankle joint
  • FDL and FHL entered at same level, just more posterior. Tendons share a common sheath 25% of the time

Not on exam

23
Q

Where would you inject the anterior group?

A

Tendon sheaths entered 4-5 cm proximal to ankle joint

Not on exam

24
Q

What are the indications of tenography?

A
  • CFL (calcaneofibular ligament) tears (MORE accurate than arthrogram)
  • Tendon subluxation or dislocation
  • Tendon stenosis
  • Tendon rupture (MRI would be the GOLD standard***)