MSK Flashcards
the characteristic long fibers are under voluntary control allowing us to do what
contract a muscle and move a joint
skeletal muscle contains long organized units called what
muscle fibers
MSK consists of what kind of muscles
cardiac
skeletal
smooth
what 3 things follow the fibrous partitions between the bundles of muscle
blood vessels
lymphatics
nerves
Muscle patterns have fibers that run _____ to the bone, have a _____ shape, or occur in a ______ pattern
parallel
fan
pinnate (uni-, bi-, multi-, circum-)
what does pinnate mean
feather like
attachment of the muscle occurs at the prox and distal portions of the bundle…this attachement is called a what
tendon
what is a tendon
a collection of tough collagenous fibers
what is a synovial sheath
a tubular sac surrounding a tendon that has 2 layers
fluid separates the 2 layers of the sheath and occurs in the shoulder, hand, wrist, and ankle
sheath helps significantly with US
support and strength of a joint results in part from the ______
ligaments
what is a ligament
short bands of tough fibers connect bones to other bones
important for knees, ankles, and shoulders
what is a bursa
saclike structure surrounding joints and tendons containing a viscous fluid
what are nerves
the conduits for impulses to and from the muscles and central nervous system
what parts of the body does MSK deal with
shoulder elbow wrist hip thigh ankle
what is the gold standard for MSK
MRI
what are the 4 types of tendons
biceps
subscapularis
infraspinatus
supraspinatus
define location of the biceps
located on the anterior surface of the humerus
define location of the subscapularis
located anterior medially on the rotator cuff
define location of the infraspinatus
located posteriorly to the shoulder
define location of the supraspinatus
abducts the arm at the shoulder
acute disease may image a sheath that is ______ than the contained tendon
thicker
what are 2 ALWAYS things to do when scanning tendons
image contralateral side for comparison
image 2 planes
describe the Achilles’ tendon
tendon of the posterior calf attaching the gastrocnemius and soleus muscle
thickest and strongest tendon
normally 5-7 mm in thickness and 12-15 cm in diameter
_______ imaging of the LIGAMENTS is the only method used to image injury
longitudinal
why is transverse imaging of ligaments not helpful
because ligament is blending with the surrounding fat
______ ligament helps maintain the proper location of the long biceps tendon within the bicipital groove
coracohumeral
______ and ______ flexor tendons have a surrounding synovial sheath that allows smooth motion of the pulley system of the hand
superficial and deep
what do normal dynamics of the muscle image easily in real time
because contraction of the muscle increases the muscle thickness and hypoechogenicity
name a muscle that has echogenic obliquely oriented connective tissue between the muscle bundles
bipennate gastrocnemius muscle
what does a small central tendon do
serves as the anchor
normal nerves have a _________ appearance when compared with muscle but are _________ to tendons
hyperechoic
hypoechoic
the longitudinal plane of nerves reveals a ________ pattern with parallel inner linear echoes similar to the tendon
fibrillar
in transverse imaging the nerve fibers appear _______ with a _______ perineurium surrounding each fiber
hypoechoic
hyperechoic
name the upper limb nerves
suprascapular
median
radial
ulnar
name the lower limb nerves
sciatic - largest nerve in body
popiteal
what is a bursa
small sac between two moving surfaces, usually tendon and bone, in the bursa
what are the 2 types of bursa found in the body
communicating
noncommunicating
what is one bursa communicating bursa seen often which is located in the medial popliteal fossa
baker’s cyst - pain in knee o prox calf, swelling
any bursa measuring greater than ____ mm is enlarged and needs to be compared with the normal contralateral side2
2
sonographic evaluation of MSK
higher frequency transducer unless patient has larger joints
positioning of the joint of interest is an IMPORTANT part of the exam
place patient is comfortable position that allows for good ergonomics
tissue harmonics aid in identifying fluid collection
color and power doppler
dynamics movements
what 2 tendons lack a synovial sheath
achilles and patellar
what are indications for shoulder sonography
shoulder pain or swelling pain with joint rotation weakness with arm elevation trauma decreased range of motion evaluation of soft tissue masses
describe rotator cuff
shoulder anatomy is quite complex, with numerous bursa, muscles, and tendons surrounding the joint
comparison with the contralateral normal shoulder always is helpful in determining the absence or presence of pathology
what exam is used to for the shoulder during ultrasound
13 point shoulder US exam
describe shoulder biceps tendon subluxation / dislocation
the dislocation of the biceps tendon from the bicipital groove
when small amount of effusion is seen posterior to the tendon it might indicate what
mild tenosynovitis
describe rotator cuff tears
biceps tendon rupture, falls, and shoulder dislocations are a few causes of an acute rotator cuff tear
describe carpal tunnel
easiest to see in transverse
locating the ulnar artery at the wrist crease helps orientation
primary entrapment or compression neuropathy of the median nerve
indications for wrist sonography
masses loss or decrease of digital mobility pain and swelling trauma foreign body location numbness of the middle and index finger weakness or clumsiness of the hand tingling with nerve percussion - Tinel's sign pain w/ wrist flexion when sustained for a min or longer - Phalen's sign
describe normal achilles’ tendon
largest tendon of the body
may develop tendinitis
AP diameter = 5-6 mm
tendon thickens due to inflammation or trauma
indications for achilles’ tendon sonography
abn Thompson test trauma displacement of Kager's fat pad knot or bulge over prox tendon audible pop or snap followed by a sharp pain inability to stand on toes swelling heel pain for more than 4 weeks descreased strength or mobility postoperative monitoring
describe Thompson test
plantar flexion will not occur with squeezing of calf while patient is kneeling on chair
what shape does the achilles’ tendon demonstrate in transverse
oval
describe tendinitis
MOST COMMON tendon abnormalities is inflammation
elasticity loss
disease such as rheumatoid arthritis
overuse or acute trauma
describe anisotropy artifacts
sound beam misses the transducer on the return because of the curve of the structure
