This document discusses the classification and mechanisms of tissue injuries. It covers soft tissue injuries, hard tissue injuries, and special tissue injuries. The three phases of the general repair process are described as the acute inflammatory response, matrix and cellular proliferation, and remodeling and maturation. Basic biomechanics of muscle-tendon-bone injuries and the muscle-tendon junction are also outlined. Specific sections cover ligaments and tendons, bone, fibrocartilage menisci, and muscle injuries and healing processes.

1. CLASSIFICATION AND MECHANISMS OF INJURIES

2. OBJECTIVES MECHANISMS OF INJURY TISSUE-BASED CLASSIFICATION GENERAL PATHOLOGY OF THE REPAIR PROCESS BASIC BIOMECHANICS OF TISSUE INJURY

3. OBJECTIVES LIGAMENTS AND TENDONS BONE FIBROCARTILAGE MENISCI OF THE KNEE MUSCLE

4. MECHANISMS OF INJURY PRIMARY INJURY: 1) DIRECT OR EXTRINSIC INJURY 2) INDIRECT OR INTRINSIC INJURY 3) OVERUSE INJURY: A) ACUTE REPETITIVE FRICTION B) CHRONIC REPETITIVE MICROFATIGUE

5. MECHANISMS OF INJURY SECONDARY INJURY: 1) SHORT TERM – PRIMARY INJURY MISMANAGED 2) LONG TERM – DEGENERATIVE PROBLEMS ( ACL )

6. TISSUE-BASED CLASSIFICATION SOFT TISSUE INJURIES: 1) SKIN AND DEEP FASCIA 2) MUSCLE-TENDON UNIT AND TENDOPERIOSTEAL ATTACHMENTS 3) MUSCLE COMPARTMENTS 4) JOINTS AND THEIR ASSOCIATED STRUCTURES 5) INTEVERTEBRAL DISC

7. TISSUE BASED CLASSIFICATION HARD TISSUE INJURIES: 1) BONE FRACTURES, OSTEOCHONDRAL FRACTURES AND AVULSIONS 2) PERIOSTITIS 3) STRESS FRACTURES 4) HYALINE ARTICULAR AND EPIPHYSEAL CARTILAGE INJURIES

8. TISSUE BASED CLASSIFICATIONS SPECIAL TISSUE OR ORGAN INJURIES: 1) BRAIN AND PERIPHERAL NERVES 2) EYE, NOSE, SINUSES, LARYNX, TEETH 3) THORACIC, ABDOMINAL AND PELVIC ORGANS

9. GENERAL PATHOLOGY OF THE REPAIR PROCESS THREE PHASES: ( ALVAREZ ET AL 1987 ) 1) THE ACUTE INFLAMMATORY RESPONSE ( APPROX.0-72H AFTER INJURY ) 2) THE MATRIX AND CELLULAR PROLIFERATION PHASE (72H-6/52 ) 3) REMODELING AND MATURATION OF HEALING ( 6/52 – 7/12 )

10. BASIC BIOMECHANICS OF TISSUE INJURY MUSCLE-TENDON-BONE INJURY: 1) “ TWO-JOINT MUSCLES” – RECTUS FEMORIS AND HAMSTRINGS 2) ECCENTRIC AND LESS CONCENTRIC LOADING – JUMPERS KNEE

11. BASIC BIOMECHANICS OF TISSUE INJURY MUSCLE-TENDON JUNCTION: - THE TERMINAL MUSCLE SARCOMERE INFOLDING TENDON INJURY: SPONTANEOUS TENDON RUPTURE:

12. LIGAMENTS AND TENDONS 1) STRUCTURE AND BIOMECHANICS OF LIGAMENTS AND TENDONS 2) CORRELATION OF COLLAGEN FIBRIL SIZE WITH MECHANICAL PROPERTIES OF TISSUE 3) THE EFFECTS OF IMMOBILIZATION OF LIGAMENTS

13. BONE 1) ACUTE FRACTURES 2) AVULSION FRACTURES 3) STRESS FRACTURES: THRESHOLD LEVEL VS CYCLIC LOADING MEASURE OF PLASMA HYDROXYPROLINE (BONE RESORPTION )

14. FIBROCARTILAGE MENISCI LOCATION OF THE TEAR DICTATES THE RESPONSE TO THE INJURY

15. MUSCLE TWO COMPETING PROCESSES DURING MUSCLE HEALING: 1) REGENERATION OF THE DISRUPTED MUSCLE FIBRES 2) THE PRODUCTION OF CONNECTIVE TISSUE COLLAGEN

16. MUSCLE - IMMOBILIZATION ( LESS POSSIBLE ) WILL REDUCE CONNECTIVE TISSUE AND ASSIST PENETRATION OF REGENERATED FIBRES - STRETCHED MUSCLES WILL INCREASE NUMBER OF TERMINAL SARCOMERES, REDUCE INTRAMUSCULAR CONNECTIVE TISSUE