1 / 166

Chapter 14

Chapter 14. Injuries to the Tissues. OA 10.21. Differentiate between a primary injury and secondary injury. Objectives. Introduce the terminology associated with injury classification Introduce biomechanical forces that cause injuries Explain biomechanical concepts for various tissues.

reyna
Download Presentation

Chapter 14

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 14 Injuries to the Tissues

  2. OA 10.21 • Differentiate between a primary injury and secondary injury

  3. Objectives • Introduce the terminology associated with injury classification • Introduce biomechanical forces that cause injuries • Explain biomechanical concepts for various tissues

  4. Injury classification • Intrinsic • Infection (viral, bacterial) • Extrinsic • Tissue stressed to the point of mechanical failure due to excessive force

  5. Extrinsic injury classification • Primary Injury • Direct immediate consequence of excessive force (trauma) • Secondary Injury • Delayed injury some time after initial trauma • An accommodation to the primary injury

  6. Extrinsic injury classification • Acute Injury • Mechanical failure of soft tissue due to excessive force occurring in a single bout • Sudden onset of short duration

  7. Extrinsic injury classification • Chronic Injury • Mechanical failure of soft tissue due to repeated micro-trauma occurring over an extended period of time • Gradual onset and are of prolonged duration

  8. Injury classification • Microtrauma • Occurs with repeated submaximal forces over time, and the tissues are unable to adapt • Macrotrauma • Occurs when a single force exceeds the tissue’s failure point

  9. Open vs. closed • Open • Exposed • Breaks the surface of the skin • Closed • Unexposed • Any injury that does not involve disruption of the skin surface

  10. Mechanical stresses • Load/Stress • External/internal force acting on the tissue • Force = Mass x Acceleration (F=ma) • Deformation/Strain • Extent of deformation under loading

  11. Load Deformation load/deformation • Mechanical force causes deformation • Degree of deformation depends on: • Tissue composition • Speed of applied load • Frequency of loading • Direction of loading

  12. Yield point • Load is greater than mechanical capabilities of the tissue • Elastic limit of the tissue has been reached • Mechanical failure occurs Ultimate Failure Point Load Yield Point Elastic Region Plastic Region Deformation

  13. Tissue stresses • Five primary mechanical forces that cause injury • Tension • Compression • Bending • Shear • Torsion

  14. Tissue stresses • Can occur alone or in combination • Type of force = Mechanism of Injury (MOI)

  15. tension • Creates a pulling action trying to elongate the structure • Longitudinal “tearing” stress • Overstretched tissue (i.e. valgus force)

  16. Valgus force

  17. compression • Creates a pushing action tending to shorten the structure • Stress is applied at each end (i.e. FOOSH)

  18. FOOSH

  19. bending • Loading about an axis – Combination of tension and compression

  20. Shear force • Force that acts perpendicular to the surface of a structure

  21. Shear force

  22. torsion • Load applied causing structure to twist about an axis

  23. Combined loading • Tissue is seldom loaded in one mode only • Subjected to multiple indeterminate loads • Geometric structure is irregular

  24. forces

  25. OA 10.22 • Give an example of each of the 5 mechanical forces that cause injury.

  26. Superficial injuries

  27. Integumentary System • Skin and structures derived from it • Hair, nails, sweat and oil glands

  28. Functions • Regulate body temperature • Protects body • Receives stimuli • Temp, pressure, pain • Eliminates waste • Sweat

  29. Three Layers • Epidermis: • Most Superficial

  30. Three Layers • Dermis: • Tough, Leathery Fibrous Connective Tissue • Partly Vascularized

  31. Three Layers • Subcutaneous (Hypodermis): • Superficial Fascia • Mostly Fat (Insulate & Absorb Shock) • Anchors Skin to Underlying Structures

  32. Three Layers

  33. Injurious Mechanical Forces • Friction • Scraping • Compression • Tearing • Cutting • Penetrating

  34. Open Vs. Closed • Open • Exposed • Breaks the surface of the skin • Closed • Unexposed • Any injury that does not involve disruption of the skin surface

  35. Abrasions • Scraping away of the superficial tissue • Sliding or skidding across a surface • Superficial in depth, large in area • Bleeding is minimal, risk of infection is great

  36. Laceration • Irregular cut caused by tearing forces • Jagged wound edges • Can be minor or very deep

  37. Puncture • Penetration of the skin by an object • Most susceptible to infection– why? • Impaling = object is embedded & partially sticks out

  38. Incision • A clean, straight, knife-like cut • Commonly caused by a surgeon

  39. Avulsion • Tearing away of tissue, commonly paired with a laceration. • Flap avulsion – tissue is still connected

  40. Calluses • Skin thickening due to increased friction or intermittent pressure

  41. Blister • Excessive friction combined with shear forces causing fluid build-up under the skin

  42. General Principles Of Wound Care

  43. Chain of infection pathogen

More Related