Tendon and Ligaments Flashcards
What might cause injury in tendon?
Degeneration (e.g. ease)
Trauma.
Often the above will lead to overstraining
Why is tendon prone to re-injury?
Scar tissue replaces damaged tissue and is not as compliant/less strong. The limited ability of tendon to heal may be due to its poor vascular blood supply.
What is the function of tendon?
To transmit load from muscle to the bone to cause movement.
What are the functions of ligaments?
To attach bones to each other.
To guide joint movement but limit freedom of movement.
Sometimes proprioception
What is the difference in tendons for muscles:
a. generating large amounts of force,
b. generating fine movements
a. short, broad tendons
b. long thin tendons
Why do tendons have a low metabolic rate?
Very low oxygen consumption and low blood supply.
What is a possible reason for this?
To prevent necrosis when the tendon is under tension.
How might a tendon around a bone (compression) differ to the region that is under tension?
Collagen type 2
GAGs
Fibrocartilagenous
May have bursae
What are the two functional types of tendon and how do they differ?
a. Positional tendon - stiffer to keep things in position
- greater number of smaller diameter collagen fibres
b. Energy Storing Tendon - more elastic so that it can store energy.
- larger collagen fibres
Name another reason why healed tissue may be more prone to injury
CRIMP pattern does not re-form
What are the main components of tendon?
Collagen type 1
Elastin
Proteoglycans
How is the arrangement of collagen molecules suited to the function of tendon?
Quater-stagger arrangement of collagen molecules arranged head to tail cross linked by lyslyl oxidase. COMP also present which holds collagen molecules close together to form fibrils. The cross linked structure is very hard to achieve during repair.
Explain the problem that would occur if there is too much matrix
Too thick => less elastic and heavy.
Define stress and strain.
Stress = load experienced per unit area Strain = % length change
Explain the non-linear,viscoelastic properties of tendon.
Creep: deformation still occurs under constant load
Stress relaxation= stress experienced under constant load decreases (due to stretching of the tissue)
Hysteresis=some energy stored is lost as thermal energy=>energy released when unloading is less than needed to load the tissue.
