Ultrasound Flashcards
Tendons can resist traction up to ______ per ____
They can only tolerate _____ elongation before being damaged
1000kg per 10mm^2
Elongation of 6%
Tendons have ____ metabolism. Increased by ____ and ____
slow metabolism even during activity.
Can be increased significantly by inflammation and trauma.
The _____ is a thin connective strip surrounding the primary, secondary and tertiary bundles of a tendon, as well as separates them.
Endotenon
The _____ is a thin band of stronger connective tissue that envelops the whole tendon
Epitenon
Tendons can be divided into two types:
1.
2.
- Supporting (or anchor)
2. Sliding tendons
Anchor tendons:
- two examples
- Size in relation to sliding tendons:
- Lack _____
Achilles, patellar
bigger and stronger
synovial sheath
_____ is a connective lamina external to the epitenon on anchor tendons providing stability
Peritenon
Sliding tendons are wrapped in ________.
Function:
a covering sheath (teno-synovial sheath)
guarantee better sliding and protection to the tendons when they run adjacent to irregular osseous surfaces, sites of potential friction.
The sites of union between tendon and muscle or tendon and bone are named _____ or _____ respectively
myotendinous or osteotendinous junctions
latter is also called enthesis.
myotendinous is usually more easily discernable
osteotendinous can be fibrous or fibrocartilaginous according to the tendon mobility, the angle formed between the tendon fibers and the bone. Also due to presence of a retinaculum underneath.
______ scans are optimal to measure tendon thickness, as it can be overestimated when measured on other axis
transverse view (short axis)
Ultrasound evaluation can be affected by ______ artifacts. Describe?
anisotropy - when the US beam is not orthogonal to the course of the tendon fibers, both a decrease of reflected and an increase of the diffracted echoes occur, thus resulting in a significant or partial reduction of tendon echotexture.
Ligaments are ____, ____ and have higher amount of ____ with comparison to tendons
Thinner, shorter, higher amount of elastin
Ligaments can be subdivided into ____ and ____ ligaments. Describe
- intrinsic - capsular thickening than true ligaments and are designed to provide capsular strengthening.
- extrinsic - independent from the fibrous capsule and can be further classified as extracapsular and intracapsular.
On ultrasound, ligaments are most often assessed by ____ view.
long axis - no diagnostic value in short axis due to less homogeneity and thinner, shorter tendons.
On US, ligaments appear as _______ bands, _____ thick, lying close to ____. Usually appear _____ -echoic, although echogenicity may vary according to ligament course.
Homogeneous bands, 2-3mm thick, close to bone, hyperechoic
______ is the connective tissue interspersed between the outer nerve sheath and the fascicles.
inter-fascicular epineurium. - houses the nerve vasculature.
Systematic scanning on ____ axis planes is preferred to follow the nerves contiguously throughout the limbs. Once detected, nerve is kept in the center of the US image in its ____ axis and then followed proximally and distally shifting the transducer up or down according to its course.
Called the ____ technique.
short axis
lift technique - examiner is able to explore long segments of a nerve in a few seconds throughout the limbs and extremities.
Cartilage is a greatly specialized type of connective tissue, mainly composed of _____.
It is _____ and ____.
The solid component of cartilage is formed of _____ that are scattered in a firm gel-like substance, ______, consisting of collagen and proteoglycans.
water (70-80% by wet weight)
avascular, aneural
cells (chondrocytes)
(extracellular matrix - collagen and proteoglycans)
Collagen forms a network of ____ which resists the swelling pressure generated by the proteoglycans
fibrils.
In the MSK system, cartilage is classified as either ____ or ____.
1. Which type containes more collagen and is more resistant to tensile strength?
hyaline, fibrous
fibrocartilage.
fibrocartilage (as opposed to hyaline cartilage) has a higher amount of collage and is found in what 6 locations in the body?
- Intervertebral disks
- symphyses
- glenoid labra
- menisci
- Round ligament of the femur
- at sites connecting tendons or ligaments to bones
Which type of cartilage is most common variety of cartilage?
Where is it found? (3)
Hyaline cartilage
- costal cartilage
- epiphyseal plates
- covering bones in joints (articular cartilage)
The free surfaces of most hyaline cartilage (no articular cartilage) are covered by a layer of fibrouse connective tissue called _____.
perichondrium
Hyaline cartilage is stratified and divided into four zones
- superficial
- middle
- deep
4 calcified (hardly detectably by US)
Orientation of collagen fibers varies through the _______ of articular cartilage in order to give better tensile strength. The fibrillar framework seems to have an _____ arrangement
4 zones (superficial, middle, deep, calcified) arcade-like arrangement
_____ is easily detectible by US as a homogeneously hypoanechoic layer delimited by thin, sharp and hyperechoic margins
hyaline cartilige
Normal articular cartilage appears as a well-defined layer with these three distinguishing features:
- high degree of homogeneous transparencey due to its high water content.
- sharp and continuous synovial space-cartilage interface (superficial margin)
- Sharp hyperechoic profile of the bone-cartilage interface (deep margin)
The synovial space-cartilage interface is ____ than the bone-cartilage interface. Both margins are best visualized when the direction of the US beam is _____ to the cartilage surface
thinner; perpendicular
______ is essential for measuring thickness of cartilage
visualization of the cartilage margins (deep and superficial margins)
Cartilage thickness ranges from ____ on the articular surface of the head of the proximal phalanx to ____ on the lateral femoral condyle of theknee joint
0.1mm; 2.6mm
_____ and ____ are hallmarks of normal cartilage
sharp margins, homogeneous echotexture
Muscle is externally surrounded by a thick connective sheath called the ______.
From the internal aspect of this sheath, several septa depart to constitute the _____, which surrounds several bundles of muscular fibers, named _____.
epimysium
perimysium - fascicles
Very light and thin septa arising from the perimysium spread into the fascicles to surround every single muscular fiber and thus form the _____
endomysium
The extremity of a muscle may continue as a tendon or insert onto the ____, ____ or the ____.
periosteum, aponeurosis, dermis
Each muscle presents at lease one _____ and two _____.
muscular belly
tendons - one at the origin and the other at the insertion.
Muscles with fibers parallel to the longitudinal axis (abdomen, head and neck) are made for ____.
Conversily, the uni-, bi-, and circum- pennate structures (muscles of the limbs) can bear _____
bearing reasonable weights for long distance activities.
greater weight for a shorter period of time.
The epimysium appears as a hyperechoic external band _____ thick, continuing without interruption along the corresponding tendon profile on longitudinal US scans
2-3mm
The ____ can be appreciated as a hyperechoic lines separating the contiguous hypoechoic muscular fascicles from one another.
perimysium.
____ is the angle measured between the muscular fibers’ direction and the central aponeurosis axis (usually corresponding to the longitudinal muscular axis).
The value of the angle varies depending on ____ of the muscle and, within the same muscle, on the ____ state
pennation angle
function of the muscle, functional state (contraction/relaxation)
In ultrasound transverse views, the muscle is sectioned according to a plane that is ______ to the muscular longitudinal axis. The 1st and 2nd order fascicles present an ______, defined by thin, elongated, hyperechoic septa, corresponding to the perimysial fibro-adipose septa
orthogonal, irregular polygonal shape
