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Page 1
MSK Ultrasound: The Basics and
The Future
Kate G. Hartley, M.D.
Director, MSK Imaging Fellowship
Assistant Professor of Radiology and Emergency Medicine
Department of Radiology and Radiological Sciences
Vanderbilt University
Disclosures
• I have no commercial or financial interests to
disclose
Educational Objectives
1. Discuss the advantages and disadvantages of
ultrasound for evaluation of the MSK system
2. Identify the normal appearance of structures
commonly encountered in MSK imaging
3. See common pathologies that can be assessed
with US
4. Learn about current experimental MSK
applications of HIFU
Advantages • Low-cost (1)
• Patient friendly (2)
• Focused exams
• Dynamic, real time exams
• Excellent spatial resolution
– 150 microns v 450 microns (MRI)
– Even greater resolution with up to 70 MHz probes – 30microns
• Contralateral comparisons
• Portable
• No ionizing radiation or contrast 1.Jacobson JA. Ultrasound in sports medicine. Rad Clin NA 2002;40(2):363–86.
2. Middleton WD, Payne WT, Teefey SA, Hildebolt CF, Rubin DA, Yamaguchi K. Sonography and MRI of the shoulder: comparison
of patient satisfaction. AJR 2004;183(5):1449–52.
Disadvantages
• Operator dependant
– Good technique, transducer selection, setting, etc.
• Dependant on body habitus
– Advances in tissue harmonics have helped in these
challenging cases(5)
• Artifacts that mimic pathology
5. Rosenthal SJ, Jones PH, Wetzel LH. Phase inversion tissue harmonic sonographic imaging: a clinical utility study. AJR
2001;176:1393–8.
Anisotropy
• Property of all tendons
• Occurs when US beam not 90o
• Can simulate pathology
Page 2
ULTRASOUND BEAM
PERPENDICULAR TO TENDON
ULTRASOUND BEAM
OBLIQUE TO TENDON
NORMAL ECHOGENICITY
OF BICEPS TENDON
ARTIFICIALLY LOW
ECHOGENICITY
Cases and Problem solving
Shoulder Pain Normal Anterior Tibial Tendon
Rotator Cuff Normal US appearance
• Homogeneous
echotexture
• Convex external
contour
• Smooth bony
margins GT
HH
Complete Tear of Supraspinatus Tendon
De Jesus et al, AJR 2009; 192:1701-1707
Page 3
Partial Thickness Articular Sided Tear
Dinnes J, Loveman E, McIntyre L, Waugh N. The effectiveness of diagnostic tests for the assessment of shoulder pain due to soft tissue disorders: a systematic review. Health Tech Assess 2003;7(iii):1–166.
Arm weakness, elbow pain
Arm weakness, elbow pain Complete Distal Biceps Tendon Rupture
Medial Elbow Pain
Common Flexor Tendons
Make the Diagnosis:
Tendinosis/Tendinopathy
• Thick, heterogeneous tendon
• Nodular, hypoechoic areas
• Calcification
• Interstitial splits
• Increased Doppler flow (variable)
Page 4
Calcific Tendinosis, Subscapularis Lateral Epicondylosis
Intrasubstance tearing neovascularity
Medial Ankle Pain
Tibialis posterior longitudinal split tear
Partial Achilles Tendon Tear/Tendinosis
Joints Advantages
• More accurate, potentially more therapeutic joint
injections
– Blind knee joint injections may miss the joint in up to
29% of cases (3)
– Blind subacromial injections may miss 24-31% of the
time (4)
3. Jackson DW, Evans NA, Thomas BM. Accuracy of needle placement into the intra-articular space of the knee. JBJS Am 2002;84A(9):1522–7. 4. Henkus HE, Cobben LP, Coerkamp EG, Nelissen RG, van Arkel ER. The accuracy of subacromial injections: a prospective randomized magnetic resonance imaging study. Arthroscopy 2006;22(3):277–82.
Page 5
Aspiration of Shoulder Effusion
H
G
Elbow Effusion
Ulna
Hip Effusion
Head
Neck
Knee Effusion from OA
Where should I tap this joint? Ultrasound guides
successful aspiration
Page 6
Bursae
• Common locations
– Subacromial, greater trochanteric, olecranon,
semimembranosus/medial gastrocnemius
• Compressible
• Thin, hypoechoic structures, <1-2 mm when not
distended.
Popliteal Mass
Chronic Olecranon Bursitis
Olecranon
Muscle
Normal Muscle
Long axis Short axis
Indirect trauma/ strain
Page 8
Fascicular Pattern of Nerves
Transverse Longitudinal
Hand Tingling
Yesildag A, Kutluhan S, Sengul N. The role of ultrasonographic measurements of the median nerve in the diagnosis of carpal
tunnel syndrome. Clin Radiol 2004;59:910–5.
Carpal Tunnel Syndrome
Radial nerve
Page 9
Screw tip abrading the nerve
Successful perineural injection
Ligaments Pitcher with medial elbow pain
Valgus Stress on Elbow
www.essr.org
Nazarian LN, et al . Dynamic US of the anterior band of the ulnar collateral ligament of the elbow in symptomatic major league
baseball pitchers. Radiology 2003;227(1):149–54.
Page 10
Ankle Sprain
F
T
Ankle Sprain
Bone
• Brightly echogenic line with acoustic shadowing
• Things that can be seen
– Unsuspected stress fractures
– Degenerative changes
– Erosions from rheumatic disease or osteomyelitis
Persistent Shoulder Pain
(6 months after MVA)
Unsuspected Humeral Impaction Fracture
Rib Fracture Missed on Plain Film
Non-tender Tender
Targeted problem solving
Page 11
Child with foot pain and swelling Power Doppler of Foreign Body Reaction
Intraoperative tendon injury
index digit
Intraoperative tendon injury
long finger
Page 12
The Future.
Surgery without knives
• “Focused ultrasound is an early-stage, non-
invasive therapeutic technology with the potential
to transform the treatment of many medical
disorders by using ultrasonic energy to target
tissue deep in the body without incisions or
radiation”
-Focused Ultrasound Foundation
The Technology
• High intensity focused ultrasound—provides the
energy to target and treat deep tissues in the body
precisely and noninvasively
• MRI -- used to identify and target the tissue to be
treated, guide and control the treatment in real
time, and confirm the effectiveness of the
treatment.
Focused Ultrasound Physics
http://www.medgadget.com/2012/10/exablate-mr-guided-focused-ultrasound-approved-in-u-s-for-pain-treatment-in-cancer-patients-with-bone-metastases.html
Focused Ultrasound Foundation Focused Ultrasound Foundation
Page 13
Focused Ultrasound Foundation
Summary
• Ultrasound is robust tool, complimentary to MRI,
in the diagnosis of MSK pathology
• Relative low cost, portability, real-time imaging for
on the spot clinical decision making and the ability
to guide intervention are driving increasing
popularity
• While in its relative infancy, HIFU is capable of
becoming a revolutionary new, totally non-invasive,
radiation free, treatment option
Recommended