1. MSK ULTRASOUND Ramon Ylanan, MD CAQSM
Team Physician University of Arkansas Razorbacks
Director Primary Care Sports Medicine Fellowship UAMS NW
Assistant Professor Family and Preventative Medicine UAMS NW

2. Conflicts of Interest
I have no conflicts of interest regarding this presentation, nor do I support one manufacturer over another

3. Objectives
Recognize basic scanning techniques, probe placement and probe orientation
Differentiate between common structures such as muscle, tendon, ligament and bone
Outline appropriate uses for diagnostic ultrasound and terminology
Identify common findings associated with tendinopathy

4. Outline Principles of Sound MSK US 101 Pathology under US
Equipment
Knobology
Terminology
Pathology under US
Advantages and limitations to MSK US

5. Outline Principles of Sound MSK US 101 Pathology under US
Equipment
Knobology
Terminology
Pathology under US
Advantages and limitations to MSK US

6. Principles of Sound It’s all about frequency
<20Hz (lower frequency)
Whales, elephants
20Hz -20kHz (audible sound)
Humans
>20kHZ (higher frequency)
Dogs, dolphins, bats

7. Principles of Sound Why is sound important in MSK US
Higher frequency sound
Greater resolution
Shorter depth of sound penetration
Lower frequency sound
Less resolution
Greater depth of sound penetration

8. Principles of Sound How does it work in MSK US
Transducer crystals produce sound waves
Piezoelectricity
conversion of electricity to sound
Sound bounces off structures and returns to transducer crystals
Picture is dependent on stiffness and/or density of acoustic interface (structure)
Each body part type has a different acoustic signature
Transducer converts sound waves into electricity which machine converts into a picture
Reverse-piezoelectricity
conversion of sound into electricity

9. Outline Principles of Sound MSK US 101 Pathology under US
Equipment
Knobology
Terminology
Pathology under US
Advantages and limitations to MSK US

10. MSK 101: Equipment Console Transducers
GE, Sonosite, Terason, Arthrex, etc
Each have pros and cons
Cost ranges $20,000-$100,000
Personal preference
Transducers
Linear array transducer
Compact linear array transducer
Curved linear array transducer

11. MSK 101: Equipment Transducers Linear array transducer
Workhouse of MSK US
High frequency
Superficial structures
Able to scan most parts
Shoulder
Knee
Elbow
High resolution

12. MSK 101: Equipment Transducers Compact linear array transducer
“Hockeystick”
Subspecialty
Very high frequency
Small joints
Very superficial structures
High resolution

13. MSK 101: Equipment Transducers Curved linear array transducer
Lower frequency
Deep structures
Hip
Abdomen
Lower resolution

14. MSK 101: Knobology Each machine Modes Depth Gain
different layout, same principles
Modes
B-mode is common MSK scanning mode
Depth
Control depth of field of view
Can be modified for each transducer, but has limits
Gain
Volume or picture brightness
Just like listening to music, operator dependent

15. MSK 101: Terminology Already got some
Transducer, piezoelectricity, etc
Long axis – longtitudinal picture of target
Short axis – cross sectional picture of target
Anisotropy – poor picture due to poor scanning technique
Sound wave/transducer was not perpendicular to target

16. MSK 101: Terminology
Anisotropy

17. MSK 101: Terminology
Hyperechoic – brighter gradient, relatively more dense
Bone, tendon, ligament
Hypoechoic – darker gradient, relatively less dense
More solid cysts
Isoechoic – grey gradient, relatively equal density
Muscle
Anechoic – very dark gradient,
Vessels or fluid pockets

18. MSK 101: Terminology

19. MSK 101: Terminology
Procedure
In plane vs out of plane

20. Outline Principles of Sound MSK US 101 Pathology under US
Equipment
Knobology
Terminology
Pathology under US
Advantages and limitations to MSK US

21. MSK Pathology under US
Muscle
Tendon
Ligament
Vessles
Nerves
Bone

22. Muscle Long axis  feather-like, pennate
Short axis  starry night appearance

23. Muscle
Not this starry night!

24. Muscle

25. Muscle
Hamstring tear

26. Tendon Achilles Tightly packed, fibers of a broom, fibrillar Normal
Tendinosis/Degeneration

27. Tendon
Patellar tendon  Normal long axis
Proximal patellar tendinosis

28. Tendon
Rotator Cuff

29. Ligament
MCL
Similar characteristics
to tendon (broom, fibrillar)

30. Ligament
Elbow UCL

31. Vessels Femoral triangle N - nerve A - artery V - vein E - empty
L - lymphatics

32. Nerve Carpal Tunnel Honeycomb in short axis Fascicular in long axis
(not as tighly packed as tendon)

33. Bone
Hip

34. Outline Principles of Sound MSK US 101 Pathology under US
Equipment
Knobology
Terminology
Pathology under US
Advantages and limitations to MSK US

35. MSK US: Advantages High resolution imaging of soft tissue
Real-time imaging with dynamic evaluation
Patient experience and education
Not affected by hardware
Just can’t scan deep to the hardware

36. MSK US: Advantages Guided injections Portable No radiation
Inexpensive for patients

37. MSK US: Limitations Focal/limited field and depth of view
MRI better for wider field of view
Limited with eval of bone or intra-articular pathology
Operator dependent
Picture quality depends on sonographer skill

38. MSK US: Limitations Education is post-training
Building into fellowships now
Cost to provider for equipment
Purchase vs rent
Quality of image depends on multiple factors
Patient position
Machine
Sonographer skill

39. Basic Principles of MSK US
Know the question
What do you want to answer?
Is US the modality to properly eval?
Keep patient comfortable
If patient is uncomfortable, results will be limited
Select appropriate transducer
Know you anatomy, know transducer limitations

40. Basic Principles of MSK US
Keep control of transducer
If it’s not stable, poor picture quality
Hard to hit a moving target
Take your time
Using a 2D slice to reconstruct a 3D structure
Must use multiple planes to properly scan

41. Scanning Time

42. References
Smith, J. Finnoff, JT. Diagnostic and Interventional Musculoskeletal Ultrasound: Part 1. Fundamentals. PM&R 2009;1:64-75.
Smith, J. Finnoff, JT. Diagnostic and Interventional Musculoskeletal Ultrasound: Part 2. 6th ed. Philadelphia, PA. WB SaundClinical Applications. PM&R 2009;Vol 1:
Kremkau F. Diagnostic Ultrasound: Principles and Instruments.ers; 2002:428
Nazarian L, McShane J, Ciccotti M, et al. Dynamic US of the anterior band of the ulnar collateral ligament of the elbow in asymptomatic major league baseball pitchers. Radiology 2003;227:
O’Conner P, Grainger A. Ultrasound imaging of joint disease. Imaging 2002;14: