KINE2495 - topic 5

What factors predispose Athletes to injury ?

Intrinsic & extrinic factors

Intrinsic factors for athletic injory

Age - teenage years: muscles stranger than bones
• sex (cubital angle)
• neuromuscular, structural, or performance factors
• Body type
• mental and psychological factors (riskier athletes)
• postural deviations

Extrinsic factors for athletic injury

Exposure to an injury situation (competitive level, amount of trading m/play, position, contact vs non contact)
Environment (condition of playing surface, time of day/season, weather, laxity of officials
Equipment (footwear & protective)

Instrinic factors for athletic injury

external force impairs anatomical tissue structure or function causing injury
• Injury will cause inflammatory response
• injury dependent on tissue properties and force

Tissue Properties

load, stiffness, stress, strain

Load

external force acting on body causing internal reactions within the tissues (usually permanent or temporary deformity)

Stiffness

ability of tissue to resist a load ( greater stiffness= greater magnitude load can resist )

Stress

internal resistance to a load

strain

internal change in tissue (ie. length) resulting in deformation which can lead to injury

Tissue forces

Compression, tension, shearing, bending, torsion

Compression Force

force that squeezes the tissue (bone resists well)

Tension Force

force that pulls and stretches tissue

shearing force

force that moves across the parallel organization of tissue

Bending force

2 force pairs act as opposite ends of a structure (compression one on side, tension on other)

Torsion force

load caused by twisting in opposite directions from opposite ends

Positive stress

Positively adapts to force causes tissue to grow

Adverse stress

overloaded, or maladaptive can see injury occur
• gradually increase mechanical stress will gradually increase tissue size and strength

force divided by the __________ area over which the force acts

force divided by the anatomical area over which the force acts

Stress/strain tissue curve

how tissue/body responds to load or force
• Tissue have viscoelastic properties
• Yield point - point where elasticity has exceeded

Creep in stress/ strain curve

strain continues beyond yield point causes elasticity to change which ends with permanent plastic damage/change
Creep can start to set in over long periods of time

types of MOI for soft tissue

Traumatic and overuse

Traumatic (macrotrauma) MOI

physical injury or wound, produced by internal or external single force
• acute something has initiated the injury process
• ex. A direct blow, sudden muscle pull

Overuse (microtrauma) MOI

nature of physical activity dictates that over time injury will occur
• chronic - when it doesn't properly heal
• ex. Repetitive loading over time

Soft Tissue is made of

Collagen and elastin

Soft tissue collagen properties

• primary constituents of skin, tendon, ligament.
• protein substance strong in resisting tensile forces
• wavy configuration, which allows for an elastic -type deformation or stretch but otherwise inelastic
• Wavy configuration straightens when soft tissue under load/tension
• Hits breaking point at 6-8% of fiber length
• Tears generally in muscles rather than tendons

Soft tissue elastin properties

• protein substance
• adds elasticity
• Some soft tissue will have more elastin then others but don't want too much elastin in all (tendons)

What develops between collagen and elastin fibres on soft tissue when stationary for long periods?

Cross bridges - why W have the feeling to stretch muscle becomes stiff

Muscle strain

stretch, te'ar, rip to muscle or adjacent tissue
• can be mild to complete muscle rupture
• usually involves large force producing muscle

Muscle strain healing time

healing time depends on amount of tissue damage - generally 6 -8 weeks

Grade 1 muscle train

some muscle rider tearing (microtear - partial tear) - tenderness and painful movement but full range present

Grade 2 muscle strain

many torn muscle fibers (micro tear to complete tear)- active contraction is painful, usually a depression or divot is palpable, some swelling & discolouration

Grade 3 muscle strain

complete rupture of fibers - significant impairment initially with great deal of pain that diminishes due to nerve damage (tend to require surgery)

Muscle spasms/guarding

a reflex reaction caused by trauma
• muscle splint (tighten) the area in an effort to minimize pain through limitation of motion

Types of Muscle spasms/guarding

Clonic & tonic

Clonic Muscle Spasm

alternating involuntary muscular contractions and relaxations in quick succession

tonic muscle spasm

rigid contraction that lasts a period of time Hypertonic muscle - muscle overall stiff

muscle soreness

overexertion in exercise resulting in muscular pain
• unaccustomed activity can cause soreness
• prevent soreness through gradual buildup of intensity

Types of muscle soreness

acute onset and delayed onset

Acute Onset Muscle Soreness (AOMS)

transient muscle pain and fatigue immediately after exercise

Delayed Onset Muscle Soreness (DOMS)

pain that occurs 24-48 hours following activity that gradually subsides (pain free 3-4 days later)
• slight microtrauma to muscle or connective tissue

Tendon injuries: tendonopothy

Collagen re-absorption occurs with repeated microtrauma - results in weakened tendons
• Also occurs with immobilization- weakens the tissue & required gradually loading & condition

Types of tendon injuries

Tendinitis, tendinosis, tendosynovitis

Tendinitis

tendon inflammation with gradual onset with repeated micotrauma
• swelling and pain
• hear/feel crepitus = sticking of tendon due to stealth around it accumulation of inflammatory by-products on irritated tissue (rice crispy crackle)
• rest and modify activity

Tendinosis

nagging re-occurivinig tendon injury - poor healing of tendinitis - degenerates and results in tendinosis
• less inflammation and more visibly swollen with stiffness and restricted motion
• sometimes a tender lump will appear
• common in middle or old age
• treatment involves stretching and strength

-itis (suffix)

inflammation

osis (suffix)

Chronic breakdown of tissue

Tenisynovitis

inflammation of synovial sheath that covers tendon

Acute tenisynovitis

rapid onset. Crepitus, and diffused swelling

Chronic tenisynovitis

thickening of tendon with pain and crepitus

Myofascial Trigger Points

hypersensitive nodule within tight band of muscle or fascia
• "knot in muscles"
• Common in shoulder girdle

What causes Myofascial trigger points

mechanical stress on muscle fiber - repeated motion causes fatigue which causes trigger point

active myofascial trigger point

Pain at rest

latent myofascial trigger point

Pain with pressure

Contusion (bruise)

blow from external object that causes soft tissue damage resulting in pain, ecchymosis, swelling

Chronically confused tissue may result in

generation of calcium deposits and form myositis ossification where deposits turn into bone

atrophy

wasting away of muscle due to: immobilization, inactivity, loss of nerve function

Liagament sprain

result or traumatic joint twist that causes stretching or tearing or connective or collagen tissue
• result in joint effusion (swelling)
• result in bleeding within touch
• warm to touch, pain, point tenderness, eccymosis (brusing)

Grade 1 Ligament Sprain

some pain, minimal loss of function, no abnormal motion, mild point tenderness

Grade 2 ligament sprain

pain, moderate loss of function, swelling, and instability with tearing and separation of ligament fixers

Grade 2 ligament sprain

extremely painful, inevitable loss of function, severe instability and swelling and may also represent subluxation of joint

Grade 3 liagament sprain

grade 3 easier to treat than grade 1&2 - tissue is stretched and can't go back to ligament original stretch with rehab

Bursitis

inflammation of a bursa

• Swelling, pain, & some loss of function
• Repeated trauma can lead to calcification

bursa

fluid filled sacs that develop in areas of friction

acute bursitis

sudden irritation

chronic bursitis

overuse and constant external compression (can cause calcium deposits) causes thickening of bursa less swelling

Bone structure

diaphysis →. Main hollow cynical shaft
• contains medullary cavity (bone marrow), lined by endostium
• Epiphysis → composed of spongy cancellous some and he hyaline cartilage covering
• Periosteum → dense, white fiborous covering that penetrates done via sharpey's risers
• contains blood vessels and osteoblasts