Chapter seven the healing process, Ch 8 - Understanding Pain and its relationship to Injury,chapter nineReleiving Orthopedic Injury Pain

chapter seven

Repair

Processes that replace the dead or damaged cells with healthy ones

A sequence of 100s of events that follow, but overlap

Controlled by a complex, precisely coordinated balance of signaling factors

Relationship to Inflammation

Repair follows inflammation

Begins within a couple of days after injury

Depends on the size of the hematoma

Two types of Repairs

Reconstitution with the same type of cells as were injured

Replacement with simpler cells

Reconstruction

Occurs in cells that normally have a high rate of turnover

Most of the damaged cells are replaced by identical cells.

Some replacement with connective tissue and thus some scar formation

Replacement

By simpler cells

Results in scar tissue formation

Type of repair also known as repair by connective tissue

Can be either primary union or secondary union

Replacement(cont.)

•Primary union

–Small incision

•Secondary union

–Large gap or hole to be filled

Four Phases of Repair

Hemostasis and inflammation

Epithelialization

Proliferation

Remodeling

Phase one: Hemostasis and Inflammation

Same as hemodynamic, leukocyte migration, and phagocytosis phases of inflammation

Hemostasis is arresting bleeding (the opposite of hemorrhaging)

Macrophages scavenger cellular debris.

Circulatory and lymphatic systems remove free protein.

The more protein in the area, the bigger the scar.

Lymphatic Drainage and Exercise

Passive

Depends on external force to promote fluid movement

Contraction squeezes the lymphatic vessels and forces contents toward the vascular system.

Massage and intermittent compression pumps promote lymphatic drainage.

Phase two Epithelization

Process of developing a membranous tissue covering (epithelium) over exposed tissue or organs

Phase 3 Proliferation

•Three major events

–Angiogenesis (growth of new blood vessels)

–Collagen synthesis (also known as collagenization)

–Wound contraction (the drawing together of the wound edges)

Proliferation: Angiogenesis

Transient phase during which new vessels are formed (most later disappear)

New vessels are necessary to deliver great amounts of oxygen and nutrients to the wound for repair.

4–6 days

Proliferation:
   Angiogenesis—Capillary Budding

Capillary budding is the primary mechanism of the vascular phase.

Endothelial cells of existing the vessels at the edge of wound begin to divide.

The new cells crawl away but keep contact with the existing vessel

Proliferation:
   Angiogenesis—Capillary Budding (cont.)

New cells force themselves between existing cells, thus forcing the end cells to advance into the wound area.

Adjacent bud sprouts migrate toward one another, meet, unite, and create a capillary arch.

Proliferation:
   Angiogenesis—Capillary Archade

Arches form a network, or a capillary arcade.

Blood then begins to flow through, causing new budding.

Gives free circulation to the wound area to support collagenization

Proliferation:
   Collagen Synthesis

Manufacturing and laying down collagen in the wound space

Collagen is the principle solid substance of ligaments, tendons, and scar tissue.

Fibroblasts manufacture strands of collagen, then extrude it into the wound space.

Proliferation:
   Collagen Synthesis (cont.)

Most collagen is laid down within 15–20 days after the injury.

Wound is not very strong yet.

Collagen will realign parallel to the lines of force.

Realignment sometimes takes up to a year.

May be longer if patient is inactive.

Proliferation:
   Collagen Synthesis (cont.)

Requires great amounts of oxygen

Healing wounds normally do not have all of the oxygen that they could use.

Collagen accumulated in the damaged tissue and the tensile strength of skin wounds linearly related to oxygen availability

Increasing the oxygen in the air breathed by injured laboratory rats between days 5 and 15 resulted in greater tensile strength of their wounds

Proliferation:
   Wound Contraction

Pulling the wound edges together

Primary player is myofibroblast.

The more of these, the smaller the wound is

So, less collagen is needed to close the wound

Smaller scar

Phase Four Remodeling

•Two processes

–Contraction

–Restructuring

•That make the scar:

–Smaller

–More pale (in light-skinned people)

–Stronger

Remodeling Contraction

Collapsing and compressing capillary arcade

Collagen is relatively inactive tissue.

Doesn’t need much oxygen; therefore, doesn’t need much circulation

Remodeling Restructuring

Collagen is restructured.

Collagen fibers reorganize themselves from

haphazard to a

parallel arrangement.

Compacts scar

Gives greater strength

Remodeling
  Restructuring (cont.)

Fibers running perpendicular to the lines of force will not help keep the edges of the wound together.

Fibers running parallel to the lines of force strengthen the injured tissue.

Exercise generates the lines of force.

Active exercise is necessary during final phase of wound healing.

–Resting is counterproductive.

Exercise and Healing

•Stimulates circulation, thus increases oxygen delivery to healing tissue

•Provides force lines that are essential as a guide to restructuring collagen

–Too vigorous will disrupt the healing tissue

–Too little will not provide adequate oxygen or stress for normal healing

Healing Modifiers Immediate care procedures

The smaller the hematoma, the quicker the repair (less to repair).

The quicker RICES is applied, the smaller the hematoma.

Healing Therapeutic Exercise

Facilitate or hinder healing?

Brings more oxygen to the wound sites

Guides fiber reorientation during restructuring

Vigorous exercise will tear the healing tissue and thus delay healing.

Residual pain the next day, means the level of exercise the previous day was too vigorous.

Healing Modifiers
    Therapeutic Modalities

•Determine desired result and select the modality to accomplish it.

–Modulate pain, thus facilitating therapeutic exercise

–Promote lymph drainage

–Enhance healing

Healing Modifiers Proper Nutrition

Many vitamins and trace elements are essential to healing.

No evidence that extra amounts of these substances facilitates healing.

Lack of them, however, will hinder healing.

Injury repair consists of processes that

replace dead or damaged cells with

Most collagen is laid down within

15-20 days after the injury

Macrophages migrate into wound sites during which phase of wound repair?

Hemostasis and inflammation

Which set of comparisons accurately describes the difference between reconstitution and replacement?

Reconstitution occurs in cells with a high rate of turnover (such as skin), whereas replacement occurs in cells with a lower rate of turnover (such as muscle).

Injury repair consists of processes that:

Replace dead or damaged cells with healthy ones.

What is pain?

Number one reason individuals seek treatment

Some claim it hasn’t been adequately defined or objectively measured.

•Many definitions; our favorite:

is an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage.”

  —Merskey and Bogduk

Function of Pain: Blessing or Curse?

•Blessing

–It protects you by alerting you to danger and stimulates action that prevents or minimizes injury.

–It makes you move differently, think differently, and behave differently.

–Without pain, people could do many dangerous things without realizing it.

•Curse, if prolonged

•Prolonged or chronic pain may result in disability, atrophy, circulatory deficiency, and loss of skill, anxiety and depression.

Cause and Effect of Pain

•Simple Pain

–Tissue damage

–Alarm system alerts brain to actual or potential tissue damage

•Response aimed at protection and healing

–Results in broad sequence of events, involving many body systems, ranging from 

•Can’t think, feel, or focus on anything else, to

•Feeling nothing, even with a serious injury

–Initiates healing processes

Manifestation of Pain

•Wide range of sensations

–Burning

–Throbbing

–Tingling

–Prickly

–Itchiness

–Other odd

•Stings pulling

•Water running on skin

•Ants crawling on skin

Neuroanatomy: Major Elements

•Nerve or neuron

–The basic functional unit of the nervous system

•Central nervous system (CNS)

–Brain and spinal cord

–Integrative and control centers

•Peripheral nervous system (PNS)

–Cranial and spinal nerves

–Communicates between CNS and rest of the body