Transcript Shoulder Ultrasound

Jenelle Beadle, RDMS
Inland Imaging
November 4 th , 2014
Muskuloskeletal Sonography
• Muscles, tendons, ligaments & bursae
• Histologic anatomy and ultrasound
appearance correlation
• Common abnormalities visualized using
ultrasound
In the human body, there are…
…650 skeletal muscles.
…4000 tendons.
…900 ligaments.
… 160 bursae.
Muscles
• Isoechoic/hypoechoic (compared to fat)
• Linear hypoechoic bundles (fascicles) surrounded by echogenic
perimysium
• Epimysium & Fascia: single, hyperechoic line at the muscle
boundary (arrows)
• Perimysium: innumerable hyperechoic lines (arrowheads)
• Fascicles: hypoechoic bundles of muscle fibers in between
• Muscles are typically evaluated with ultrasound for pain and/or a
palpable abnormality.
•
Often times with a history of traumatic injury
•
Most common abnormal findings include strains/tears and tumors.
Intramuscular Sarcoma
Adductor Magnus Muscle
Intramuscular Myxoma
Gastrocnemius Rupture
Normal
• Muscle strains/tears most commonly occur in the lower extremity
•
•
typically near the musculotendinous junction
severity of muscle strain injuries are graded I, II or III
• Strain (Grade I): pain; resolves in about 2 weeks
•
•
normal
thickened and hyperechoic
• Muscle strains/tears most commonly occur in the lower extremity
•
•
typically near the musculotendinous junction
severity of muscle strain injuries are graded I, II or III
• Strain (Grade I): pain; resolves in about 2 weeks
•
•
normal
thickened and hyperechoic
With a contusion, echogenicity
may cross fascial boundaries.
• Tear (Grade II): pain with loss of function; resolves in about 4 weeks
•
intrasubstance tears; detachment from fascia or aponeurosis
•
disruption of striated pattern
•
intramuscular fluid collection with hyperechoic halo (hypervascular)
“Tennis
Leg”
Trans
Long
• Avulsion (Grade III): pain with loss of function, usually caused by strong
contraction against firm resistance
•
myotendinous (muscle to tendon) or tendoosseous (tendon to bone)
•
complete discontinuity of muscle fibers; hematoma
Musculotendinous
junction tear
Tendons (muscle-to-bone)
• Echogenic (compared to muscle)
• Linear fibril bundles of collagen in a
supporting matrix
• Short axis: “finely punctate pattern”
• multiple echogenic dots
• Long axis: “fibrillar architecture”
• multiple, closely spaced parallel lines
Trans
Long
Long Patellar Tendon
Anisotropy artifact
Anisotropy
Trans Achilles Tendon
Tendinopathy
• Sonographic evaluation: size/thickness, contour and echotexture
•
Dynamic scanning can also be helpful
• Tendinosis
•
•
•
•
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thickened, hypoechoic, hypervascular; may have some loss of fibrillar pattern
occurs with or without tendon tears
Acute: strained by traumatic injury
Chronic: general wear-and-tear (age-related changes, inflammatory disorders)
• may have calcifications present (calcific tendinosis); round or linear in shape
Chronic tendinosis predisposes a tendon to further injury
• As a result, tendons that typically affected by overuse or degeneration are also the
tendons most commonly strained or torn.
• Supraspinatus, achilles, patellar, quadriceps and common extensor (elbow) tendons
• Achilles Tendinosis
• Common Extensor Tendinosis (lateral epicondylitis)
• “Tennis Elbow” (although 95% are not in tennis players)
• usually results from repetitive motion injuries (chronic)
Normal Common Extensor Tendon
Supraspinatus Tendonisis
Quadriceps/Patellar Tendinosis
Tendon Tears/Ruptures
• Acute or Chronic
•
most tendon tears are a result of chronic overuse rather than acute trauma
• Associated with adjacent tendinosis
•
makes identifying small partial tears difficult
• Ultrasound Findings (often more easily appreciated with dynamic
scanning)
•
partial/complete nonvisualization
•
distinct focal hypoechoic/anechoic defect
•
apparent disruption of linear fibrillar architecture
•
contour abnormality
• Most commonly torn tendons are supraspinatus and achilles
• Tears are categorized
•
partial
•
full thickness (complete rupture)
• Partial Tear
• a portion of the tendon remains intact
• includes “intratendinous” tears
Long Achilles Tendon
Long Common Extensor Tendon
Long Distal Biceps Tendon
Trans Peroneal
Longus/Brevis Tendons
• Partial Tear
• with a large partial tear, some retraction of the torn tendon may be identified
Long Quadriceps Tendon
Trans Achilles Tendon
• Full Thickness Tear
• rupture that extends across the entire
width and depth of the tendon
• proximal muscular retraction of the
entire tendon
• non-functional tendon distal at
insertion
Long Patellar
Tendon
Long Achilles Tendon
Prox
Dist
Complete achilles
rupture with intact
plantaris tendon
•
absent 7-20%
Long Achilles Rupture
Trans Achilles Rupture
Ligaments (bone-to-bone)
• Isoechoic/hypoechoic (compared to tendons)
• Similar composition as tendons, but fibers are less organized
structure; more of an interlaced, woven pattern.
•
Fibrillar pattern, but slightly changing the orientation of the tranducer will bring
other fibers into view.
•
This less regular structure is what makes ligaments slightly less echogenic than
tendons.
• Injury is often associated with joint derangement (acute).
•
Sprain: stretching or tearing of a ligament (“strain”- tendon)
•
Range from invisible “micro-tears” to complete rupture
•
Most commonly injured ligaments are in the knee and ankle
• Ankle Ligaments
•
Anterior Talofibular Ligament (most commonly injured)
•
anterior lateral malleolus to anterior talus
•
best seen in w/ tendon stressed (plantar flexion)
•
injured with supination (lateral rotation of the ankle)
• iIsolated, or associated with Calcaneofibular Ligament (up to 70%)
peroneal
tendons
• Ligament Sprain/Rupture
•
Thickened & hypoechoic with surrounding fluid
•
Evidence of tear may be seen (hypoechoic area that interrupts fibers)
Ruptured
Anterior Talofibular Ligament
Normal
“a”: anterior talofibular ligament
“b”: calcaneofibular ligament
Curved lines: peroneal tendons
• Knee
• ACL: Anterior Cruciate
Ligament (can’t be seen
well enough with
ultrasound)
• PCL: Posterior Cruciate
Ligament (not commonly
injured)
• Lateral Collateral Ligament
(not commonly injured)
• Medial Collateral Ligament
Medial Meniscus (purple) & Medial Collateral Ligament (green)
Bursae
• Thin layer of anechoic fluid (synovial) surrounded by hyperechoic
walls.
• Not typically visualized unless abnormal.
• Synovial-lined sac overlying bony surfaces at areas of tendon
friction.
•
Some communicate with the joint space (ex: semimembranosus bursa)
•
Baker’s Cyst (Popliteal Cyst) typically communicates with the joint
capsule via the semimembranosus bursa.
• Bursitis:
• Repetitive motion and overuse
• Inflammatory disorders (rheumatoid arthritis, gout, etc.)
• Shoulder, elbow , hip & knee
• Most common site: Subacromial Bursa (shoulder)
• Does not normal communicate with the joint space, but can if
there is a full thickness tear.
Subacromial Bursitis
• Other common sites of bursitis…
• Prepatellar Bursa (“housemaid’s knee”)
• Infrapatellar Bursa (“clergyman’s knee”)
Prepatellar Bursitis
Infrapetellar Bursitis
Deep Infrapatellar Bursitis
• Other common sites of bursitis…
• Trochanteric (lateral hip)
Trochanteric Bursitis
Trochanteric Bursitis (Deep)
•
Between the greater trochanter and
the gluteus medius muscle insertion.
Gluteus Medius Insertion
• Other common sites of bursitis…
• Iliopsoas Bursa
Long Iliopsoas Bursitis
Trans Iliopsoas Bursitis
• Other common sites of bursitis…
• Olecranon Bursa (“student’s elbow”)
Triceps
Tendon
Long Olecranon Bursitis
Trans Olecranon Bursitis
References
•
“Skeletal Muscle Ultrasound” European Journal Translational Myology 2010; 1 (4): 145155
•
“Ultrasonographic Findings of Musculoskeletal Tissues” J Korean Orthop Assoc. 2013
Oct;48(5):334-341
•
“Sonography of Common Tendon Injuries” American Journal of Roentgenology.
2009;193: 607-618
•
“Tendon and Ligament Imaging” Br J Radiol. Aug 2012; 85(1016): 1157–1172
•
“Imaging of the Bursae” J Clin Imaging Sci 2011; 1:22
•
“Ultrasonography of tendon abnormalities” OA Musculoskeletal Medicine 2013 Jun
01;1(2):12
•
“Sonography of Lower Limb Muscle Injury” American Journal of Roentgenology.
2004;182: 341-351
•
“Full Thickness and Partial Thickness Supraspinatus Tendon Tears” Radiology 2004;
230:234–242
•
“Long Head of Biceps Brachii Tendon Evaluation...” AJR 2011; 197:942–948
•
“Ultrasound of the Shoulder” JBR–BTR, 2007, 90: 325-337
•
Gaitini D. “Shoulder Ultrasonography: Performance and Common Findings” J Clin
Imaging Sci 2012; 2: 38-38
•
Read J, Perko M. “Ultrasound Diagnosis of Subacromial Impingement for Lesions of the
Rotator Cuff” AJUM May 2010; 13 (2): 11-15
References (continued…)
• http://www.sonoguide.com/soft_tissue.html
• http://www.dynamicultrasound.org/dugphysics.html
• http://www.ultrasoundcases.info/Slide-View.aspx?cat=405&case=1858
• http://www.shoulderdoc.co.uk/article.asp?section=904
• http://www.radiologyassistant.nl/en/p50cf8392cbd97/us-guidedinjection-of-joints.html
• http://radiopaedia.org/articles/posterosuperior-impingement-of-thshoulder