Inflammation and tissue repair Flashcards
Causes of tissue damage
- Direct trauma
- microtrauma: minor damage (overuse)
- mactrotrauma: significant damage (actuate) - Surgery
- Pathology and disease process
- Problematic healing and/or presence of infection
Inflammation
A non-specific immune response that occurs in relation to any tupe of bodily injury regardless of cause; stereotyped response that is identical and predictable regardless of causative factor
Acute
Inflammation of rapid onset and rapid resolution. The majority of the response is usually over within 12-24 hours
Chronic
Inflammation that is less intense but sustained over a prolonged period of time. Chronically elevated WBC count, low grade fever and pain, often leads to dysfunction. Pathological and delays healing
Edema
A local or generalized condition in which the body tissues contain an excessive amount of fluid (interstitial tissue)
- associated with vascular insufficientices, CHF or renal failure
Infection
The presence of microorganisms that produces tissue damage. S&S of infection are similar to that of inflammation, so be aware of any acute changes in symptoms such as
- low grade fever
- pus/drainage with foul odor
- flu-like symptoms
Effusion
Fluid accumulates in joint. Type of swelling that usuallly needs drainage
- blood
- infection/cellular waste
- interstitial
Cardinal signs of inflammation
- heat - erythema - swelling - pain
- loss of function
- fever (may be seen with extensive inflammation or in the presence of infection
Things to keep in mind (3)
- Timeframes are general and will not be the same of all pts or injuries or resources
- Must consider the severity of the injury and the typ of tissue (ligs, mm, bone)
- Must utilize subjective reports and objective findings to help determine where a pt is in healing dur to the overlap of phases
Issues that may affect tissue healing (8)
- General health (age, nutrition, etc)
- Comorbidiites (diabetes, poor vascular supply, etc)
- Substance use/abuse
- Infection/foreign bodies
- Tissue type
- Severity of trauma
- Edema
- Medical treatment
3 stages of tissue repair
- Inflammatory response phase (0-4 days, peaking 24-72 hrs post injury)
- Proliferation phase (day 2 - 6 weeks, fibro-blasting repair)
- Maturation phase (3 weeks - 2 years, remodeling)
Continuum of tissue healing
Pic
Ligament healing time
One year post injury: 50-70% of normal tensile strength
- day 3-14, weeks 2-6, week 6-1 year
Muscle healing time
6 months
- days 1-5, day 5 - week 6, week 6 - month 6
Bone
Year to years
- days 1-14, weeks 2-12, week 12 - years
Stage 1: inflammation stage (S&S and treatment)
- S&S: cardinal signs of inflammation, pain to touch with muscle guarding, pain with motion, decreased strength
- treatment: control the formation of excess inflammation, control pain, (P)RICE
(P)RICE
Protection - rest - ice - compression - elevation
Stage 1: inflammation stage
Vasoconstriction -> vasodilation
Clot formation -> phagocytosis
Vasoconstriction
Shortening diameter of blood vessels in the injured areas to minimize blood loss
Vasodilation
Widening of diameter of surrounding blood vessels to bring oxygen, nutrients, and chemical mediators to the injured tissue - histamine response
Clot formation
Temporary plug is formed superficially (confines inflammation and debris)
Phagocytosis
WBCs and macrophages remove bacteria/debris from injured area (allowing progression of healing)
Stage 2: proliferation phase (S&S and treatment)
- S&S: swelling persists, cardinal signs are resolving (post 72 hr window), pain to touch and pain with motion. **all should be decreasing as the phase progresses
- treatment: facilitate healing be increasing enzyme activity, circulation, and oxygenation; prevent reinjury (tensile strength of injured tissue is still very fragile!)
Stage 2: proliferation
Revasularizaiton -> formation of scar
Revascularization
- growth of endothelial capillary bids into the wound is stimulated by lack of oxygen
- the wound becomes capable of healing aerobically
- increase oxygen delivery
- increased blood flow (increased delivery of nutrients for tissue regeneration)
Formation of scar
- formation of granulation tissue (fibroblasts, collagen, capillaries) - granular mass of connective tissue that fill in the gaps during the healing process
Formation of scar steps (7)
- Capillaries grow
- Fibroblasts arrange parallel to them
- Fibroblastic cells synthesize an extracellular matrix
- Fibroblasts produce collagen fibers that are randomly deposited
- Scar formation
- Tensile strength increases proportionate to the rate of collagen synthesis
- With increased tensile strength and decreased fibroblasts, net phase begins
Stage 3: maturation phase (S&S and treatment)
- S&S: mild swelling (should be resolving), all symptoms should continue to be resolving, ROM and strength willl gradually become comparable to unaffected side (goal of at least 85-90% of uninvolved side), pt should be returning to functional activities **as long as scar appears redder than surrounding tissue, scar remodeling is still occurring
- treatment: increase ROM, strength, and scar mobility; return pt to prior level of function
Stage 3: maturation phase
- long term phase
- includes realignment and remodeling of collagen fibers that make up scar tissue (occurs in accordance to tensile forces)
- with increased tensile forces (stress and strain), collagen fibers realign in a more efficient position
- tissue gradually appears and functions normally
- usually by the end of week 3, the scar is firm, strong,
- collagen: continually synthesis and break down
- collagen fiber orientation: scar tissue orientation based on stresses placed on it
4 outcomes of tissue healing
- Normal, full healing of like tissue
- Scar tissue formation
- Impaired healing/abscess formation
- Chronic inflammation/non-healing
Pharmacological management
- NSAIDS (ibuprofen, naproxen, Celebrex)
- steroid meds (cortisone, prednisone, dexamethasone)
- aspirin
Physical agents / interventions
- PRICE (initially)
- e-stim, ionto, non-thermal US, cryotherapy (initially)
- manual techniques
- therapeutic exercise / activities (ROM, strengthening)
