2. Injury Mechanisms and Classifications Core Concepts in Athletic Training and Therapy Susan Kay Hillman

3. Objectives Describe the anatomical reference position. Use appropriate anatomical terminology to describe the location and position of a structure relative to the rest of the body. Identify characteristics relating to the various stages of physical maturity. Explain distinctiveness of the various types of musculoskeletal tissue. Differentiate between elastic and plastic tissue properties. Classify injuries as either acute or chronic based on the onset and duration of symp­toms. Define the common chronic inflammatory conditions, including signs and symptoms. Define the various classifications of closed soft tissue wounds, including degrees of severity. Define and classify closed and open wounds of the bone and joint articulations. Classify nerve injuries according to mechanism, severity, and signs and symptoms. Identify the classifications of open (exposed) wounds.

4. Introduction Proper reference to anatomical positions, knowledge of injury terminology, and mechanisms essential for communicating effectively with other health care professionals Assist you in documenting findings, convey history information during medical referrals, and collaborate with other healthcare professionals regarding care of your athlete

5. Anatomical Reference Terminology All anatomical descriptions and references are based on standardized position of the body Anatomical Position Allows us to reference specific body regions in relation to the body as a whole and one anatomical landmark to another Avoid confusion and misinterpretation of your findings Can be standing or supine (on the spine) Standing most common and easiest to visualize

6. Anatomical Reference Terminology Anatomical position Feet together, flat on the ground, toes facing forward Legs and knees straight and in line with hip, torso and head, which are also straight and facing forward Upper limbs positioned at persons side, with elbows straight Shoulders rotated so palms are facing forward

8. Anatomical Reference Terminology Once in anatomical position one can begin to refer to specific structure using various anatomical terms Describe position of body parts with reference to other body parts or the body as a whole Also synonyms reserved for particular body regions For example anterior=structure near front of body, and anterior surface of hands is referred to as palmar or ventral

10. Anatomical Reference Terminology From anatomical position can also define three anatomical planes of movement useful in describing postural positions, motions, and function of various muscles and joints Imaginary planes that separate the body into left and right (sagittal or median), top and bottom (Transverse), and front and back (frontal or coronal) For example when nodding your head or flexing your elbow this occurs in the sagittal plane Shaking your head no or rotating your palms so it is facing backwards takes plane in the transverse Lifting arms out to the side occurs in the frontal plane

12. Anatomical Reference Terminology Patient positioning terminology important and helpful for understanding starting positions for various medical testing Supine (face up) and prone (face down) refers to patient laying down Short sitting-patient sitting on edge of table with legs hanging off the edge Long sitting patient sitting with legs out in front of them with legs on the table or floor

13. Physical Maturity Classifications Allows us to define stages of physical growth Normal anatomic and physiologic development from infancy to older adulthood Infancy: (0-12 months) physical changes occur most rapidly. Dependent neonate to a child learning motor skills such as turning, sitting, crawling and walking Gain 3 x birth weight in this time Childhood: (1-11 years) infancy to onset of puberty Steady growth and development Skeleton is immature with epiphyseal plates open to allow bones to elongate 1-5 early childhood, 6-11 middle childhood

14. Physical Maturity Classifications Adolescence: ( 11-13 through 18-20) Onset of puberty through full skeletal maturity Onset of Puberty marked by development of secondary sexual characteristics Females: menarche, pubic hair, development of breast Males: Deepening of voice, pubic hair, and facial hair Skeletal maturity marked by full closure (ossification) of epiphyseal plates and cessation of further growth in height Age at which bones complete ossification varies widely from early teens to early 20’s Adulthood (18-40 years) Indicate full skeletal maturity and development Bone and muscle mass increase through 25 to 30 years of age after which mass levels off and then slowly declines

15. Middle adulthood (40-60 years) Gradual decline in strength coordination and balance Older adulthood (> 60 years) Spans rest of human beings life Accelerating decline in strength, coordination and balance Highly individual depending on lifestyle, activity, nutrition and disease

16. Injury Mechanisms Foundation of body movements made up of several simple machines Levers, pulleys, and wedges among other more complex systems Bodies capable of performing very intricate and detailed work along with incredible feats of strength, power and endurance However, body influenced by internal and external mechanical forces that can negatively affect performance Important to understand musculoskeletal system, physical properties of the musculoskeletal tissue, internal and external mechanical forces that can cause injury

17. Injury Mechanisms Musculoskeletal Tissue Five tissue types Categorized by Soft and Skeletal Tissue Soft tissue Muscles, tendons, ligaments, and cartilage Skeletal Tissue Bone

19. Injury Mechanisms Musculoskeletal Tissue Properties Degree and location of injury often determined by tissue strength Musculoskeletal tissue has elastic and plastic (inelastic) properties. Elastic properties manifested as response to loading, stress or mechanical forces that cause stretching or deformation of tissue After stress is removed tissue returns to relatively normal state

20. Injury Mechanisms Plastic Properties manifested at end range of elastic properties rendering tissue unable to return to normal state Tissue retains some amount of deformation due to structural injury Yield point: determined by specific amount or level of stress Example: stretching a rubber band. Point at which it breaks is considered yield point Enough force to eliminate elastic property recovery and cause rubber band to undergo plastic deformation

21. Injury Mechanisms Athletic injuries occur much the same way Tissue stress determined by amount of mechanical force divided by total area affected If tissue stress, is low enough that tissue remains in elastic property zone patient may only occur minor injury or none at all If stress in high enough to force tissue to plastic property zone injury severity and tissue damage more significant

22. Injury Mechanisms Individuals and individual tissue have an ability to respond to and resist a certain amount of load or stress before deformation As load or stress increases the potential for tissue deformation also increases Type of force applied, along with the surface area acted upon by the force, also affects the injury Given same velocity localized force can result in substantially greater tissue damage than the dame force applied over a broader surface area

24. Injury Mechanisms Tissue damage may be the result: unpredictable accident or injury Overuse Overload Poor posture Skeletal immaturity Lack of conditioning Improper mechanics Fatigue Inflexibility Muscle imbalance Genetics

25. Mechanical Forces Stress or load applied to the body to cause injury or tissue deformation is a result of 1 of 5 types of mechanical force Excessive compression Squeezing or condensing of tissue due to external forces applied directly opposite of each other Bruises (contusions) Crushing injuries (compression fractures) Pinching Injuries due to direct impact

26. Mechanical Forces Shear Forces that cause tissue to “slide” over adjoining surfaces or structures in a parallel fashion Brain injuries Tibiofemoral translation injuries such as ACL and PCL injuries Blisters Lumbar spine injuries

27. Mechanical Forces Torsion Twisting mechanism that causes rotation along long axis or fixed point Opposite ends of tissue are rotated in opposite directions Example: Body rotating over Foot fixed or lower leg Occurs to bones and ligaments

28. Tension Stretching or lengthening of musculoskeletal tissue due to stress or strain Caused by pulling or drawing apart Pull of tissue in opposite direction causes tissue in between to stretch Muscle strains or ruptures commonly caused by tension within the musculotendinous unit Where muscle makes transition into tendon Weak part of muscle

29. Mechanical Forces Bending Deformation of tissue into convex or concave shapes due to axial loading Forces acting in opposite directions at different ends of tissue Or significant impact to middle of tissue while the ends are stable Convex surface undergoes tensile forces while concave surface undergoes compression forces Example: Fibula fracture with direct blow

30. Mechanical Forces Mechanical forces are not isolated Usually 2 or more mechanical forces acting on tissue at one time Complex mechanisms and forces that come together to cause injury Example: Lateral blow to knee with foot planted Compressive forces to lateral knee, bending force to medial knee, shear and tension forces to middle of knee Valgus force: toward midline Varrus Force: Away from midline

32. Time Classification Relating to Mechanism of Injury Acute Injuries Conditions that have sudden onset, short duration, and occur via mechanical forces that exceed elastic properties causing tissue deformation Single traumatic event: blunt force trauma, dynamic overload of muscle, tendon, joint capsule or ligamentous tissue

33. Time Classification Relating to Mechanism of Injury Chronic Injuries Gradual onset, prolonged duration, and occur as a result of accumulation of minor insults or repetitive stresses Exact mechanism not often known Overuse, accumulative microtrauma, repetitive overloading, abnormal friction that is greater than body's ability to heal and recover before additional stress is added “too much, too soon, too often” Often more difficult to treat overuse (chronic) injuries than acute injuries

35. Injury Classifications Sign: finding that is observable or that can be objectively measured Swelling, discoloration, deformity Crepitus: crackling, grating, or grinding sensation Symptom: subjective complaint or an abnormal sensation the patient describes but cannot be directly observed Pain, nausea, altered sensation, fatigue

36. Injury Classifications Closed (Unexposed) Wounds: Injury that does not disrupt surface of skin Contusion or bruise Signs: swelling discoloration and deformity Compression of soft tissue due to direct blow or impact Damage to small capillaries in tissue Local bleeding (hemorrhage), causing ecchymosis (discoloration of tissue), may be immediate or delayed

37. Contusion Severity First degree: superficial damage, minimal swelling, localized tenderness, no limitations to strength or ROM Second Degree: Increased pain and hemorrhage, increased area and depth of tissue damage, mild to moderate limitation sin ROM and muscle function or both Third degree: severe tissue compression, severe pain, significant hemorrhage and development of hematoma Significant limitations in ROM and muscle function Suspect damage to deeper structures such as none

38. Closed Wounds Sprains: injury to ligaments or capsular structure Ligaments attach bone to bone Injury occurs when 2 bones separate or go beyond normal ROM First Degree: mild overstretching Mild pain and tenderness, little or no disability AROM and PROM not limited but some pain at end range Firm definitive end point (feel) Degree of swelling and discoloration not great indicator of severity

39. Sprain Severity Second Degree: Further stretching and partial disruption or macro tearing of ligament Moderate to sever pain Point tenderness Eccyhmosis Swelling ROM and normal function limited secondary to pain and swelling Stress testing shows instability or laxity but still feel an end point

40. Sprain severity Third Degree: Complete disruption or rupture or loss of ligament integrity Associated with feeling or sound of a pop Immediate pain and disability Rapid swelling. Eccyhmosis and loss of function Stress test shows moderate to severe instability with no firm end point “ soft or mushy” Can be deceiving because Rom and stress testing less painful because ligament not intact

41. Strains Stretching or tearing of muscle or tendon Violent, forceful contraction or overstretching Fatigue, lack of warm up muscle strength imbalance, and dyssynchrony

42. Strain Severity First Degree: overstretching and micro tearing of muscle or tendon. No gross fiber disruption Mild pain and tenderness Typically full AROM and PROM Pain with resisted muscle contraction

43. Strain Severity Second Degree: further stretching or partial tearing of muscle or tendon fibers Immediate pain, localized tenderness and disability Varying degrees of swelling, eccyhmosis, and decreased ROM and strength Pain with active muscle contraction and passive muscle stretch May have palpable defect

44. Strain Severity Third Degree: Muscle or tendon completely ruptured Audible pop Immediate pain and loss of function Palpable defect on superficial muscles Muscle hemorrhage and diffuse swelling ROM and strength may or may not be affected or pai nful

45. Injury Classifications Open (Exposed) Wounds Injuries that involve disruption of the skin Caused by friction or blunt or sharp trauma Susceptible to infection Monitor for pus increased pain, redness, swelling, heat and red streaks running from wound to trunk If signs of infection are present refer to medical professional

47. Injury Classifications Bone and Joint Injuries Closed Fractures: disruption in continuity of bone without disruption of skin surface Traumatic (Acute): immediate pain, rapid swelling, bony tenderness, false joint, crepitus, deformity Displaced fracture concern with secondary injury Evaluate neurovascular status distal to fracture site Stress Fracture: S & S not always as obvious Onset of pain is gradual Pain or deep ache may be first noticeable during activity and subside with rest, progresses to more constant pain if offending activity continues Swelling is minimal and localized tenderness over fracture site

48. Bone and Joint Injuries Epiphyseal Injury Disruption of epiphysis or epiphyseal plate (growth plate) Can cause premature closing and growth abnormalities Dislocation Complete disassociation of 2 joint surfaces Forces cause joint to exceed passed its normal ROM Severe Stretching or complete disruption of joint capsule and supporting ligaments Pain swelling, loss of function, deformity Subluxation Incomplete disassociation of 2 joint surfaces Disability, pain, selling and joint instability varies Often history of sensation of joint slipping or giving out

49. Injury Classifications Nerve Injuries Compression or tensioning of neural structure Laceration of nerve can occur secondary to fracture, dislocation, penetrating trauma Anesthesia: no sensation Parathesia: tingling, burning, numbness Hyperesthesia: hypersensitivity Paralysis: complete loss of muscle function Nerve Injuries Neuropraxia: transient and reversible loss of nerve function Axontmesis: partial disruption of nerve Considerable atrophy and weakness due to prolonged healing 2 weeks to a year Neurotmesis: most severe nerve injury, complete severance of the nerve Neuralgia: achiness or pain along distribution of nerve secondary to irritation or inflammation Neuroma: thickening of a nerve or “nerve tumor”, secondary to chronic irritation or inflammation