Lecture 8: Ligaments, fascia and tendons (Hayward)

Question 0

what is fascia classified as?

Answer 0

irregular dense connective tissue

Question 1

what are fasciae, tendons and ligaments classified as?

Answer 1

dense connective tissue

Question 2

what are tendons and ligaments classified as?

Answer 2

dense regular connective tissue

Question 3

define ligaments

Answer 3

they are regular dense connective tissue that attach bone to bone.

Question 4

what is the function of ligaments

Answer 4

to stabilize and strengthen joints and limit the movement of bones in certain directions

they can also bind tendons to bones

Question 5

how are ligaments arranged?

Answer 5

they are taut when the joint is in the position of maximum stability.

Question 6

what is the morphologic arrangement of collagen fibers and fibrocytes in ligaments?

Answer 6

there are smaller collagen fibers and variable numbers of elastic fibers.

Question 7

what are elastic ligaments?

Answer 7

they consist mostly of elastic fibers, imparting considerable flexibility and recoil.

Question 8

what are some examples of elastic ligaments?

Answer 8

ligamenta flava and ligamentum nuchae

Question 9

are ligaments resistant to tensile (stretching) forces?

Answer 9

YES!

Question 10

define fascia

Answer 10

the connective tissue surrounding the different sub-compartments of muscle.

all layers of fascia are in continuity with each other and converge to form a common bundle of fibers or the muscle tendon

Question 11

what is the epimysium?

Answer 11

a sheet of dense connective tissue that completely surrounds and invests the muscle belly

Question 12

what is the perimysium? what is it composed of?

Answer 12

a second order of collagenous connective tissue that invade the depths of the muscle belly to ensheath muscle fibers to form muscle fascicles or bundles.

it is composed of epimysial septae

Question 13

what is the function of the perimysium?

Answer 13

it conveys blood vessels and nerve branches passing to and from the muscle fascicles.

Question 14

what can you find within the perimysium?

Answer 14

muscle spindles, proprioceptors that function as stretch receptors in muscles.

Question 15

define endomysium

Answer 15

connective tissue that surrounds each muscle fiber.

Question 16

what is endomysium composed of?

Answer 16

primarily reticular fibers that harness the margins of the muscle fibers through connections with the external lamina that surrounds each muscle fiber

Question 17

capillaries and nerve fibers pass within which type of fascia?

Answer 17

endomysial connective tissue

Question 18

define myotendinous junction

Answer 18

mysial connective tissues located at the muscle’s insertion and origin that merge and become confluent to form tendons or aponeuroses.

Question 19

define tendons

Answer 19

cylindrical regular dense connective tissue in which muscle fibers end and are attached to bones

Question 20

what is the primary function of a tendon

Answer 20

to transmit forces developed by muscles to the skeleton

Question 21

what can large tendons be used for in some animals?

Answer 21

they can be used to store elastic energy when stretched. the stored energy is recycled during subsequent movements (kangaroo is an example).

Question 22

define aponeuroses

Answer 22

tendons that consist of flat sheets of dense connective tissue that typically attach flat muscles to bone

Question 23

what are tendons composed of?

Answer 23

type I collagen fibers tightly packed into bundles.

Question 24

what is the significance of the tight bundling of collagen fibers in tendons?

Answer 24

there is little amorphous ground substance located between fibers

Question 25

how are fibrocytes aligned in mature tendons?

Answer 25

in parallel rows between bundles

Question 26

how are collagen fibers organized in tendons? (endotenon, peritenon, epitenon, paratenon)

Answer 26

they are organized into bundles by loose connective tissue septae called endotenon which contain blood vessels and nerves.

several small bundles may be further organized into larger bundles by loose connective tissue septae called PERI-tenon

peritenon is continuous with an outer layer of DENSE connective tissue called epitenon.

epitenon is invested in PARA-tenon, which consists of LOOSE connective tissue that permits movement during locomotion.

Question 27

how do vessels and nerves pass to tendons?

Answer 27

via paratendons

Question 28

where will you typically find synovial tendon sheaths?

Answer 28

in areas where friction is enhanced by greater movement and/or pressure from adjacent structures

Question 29

what reduces friction during movement?

Answer 29

synovial fluid located within the lumen of synovial sheaths

Question 30

where do vessels and nerves pass from the paratendon to the epitendon when covered by synovial sheaths?

Answer 30

they pass within the mesotendon formed by reflection of the synovial membranes

Question 31

what causes tendonitis?

Answer 31

under circumstances of repetitive movements, the lubricating function of the sheath can become exhausted and the tendon and sheath become irritated. this can be extremely painful and cause lameness

Question 32

tendons and ligaments attachment sites are typically what?

Answer 32

fibrocartilage or bone

Question 33

what are sharpey’s fibers?

Answer 33

collagen fibers of tendons that become embedded in newly formed bone during growth.