Part II: Mechanisms & Characteristics of Musculoskeletal & Nerve Trauma
Joint, Bone & Nerve Injuries
Anatomical Characteristics
 Most joints are diarthrosis joints or synovial joints
New Vocab Words
 Synovial Joint
o Articualtions of two bones surrounded by a joint capsule lined with synovial
membrane
Anatomical Characteristics
 Hyaline or articular ____________________- thin smooth covering that lines the bones
 _____________________ - a thick, ligamentous tissue that surrounds joint
 Synovial Membrane- inside liner of joint capsule that produces synovial fluid
 Additional synovial joint characteristics
o Blood and nerve supply with muscles crossing joint
Anatomical Characteristics
 Ligament- Composed of dense connective tissue arranged in parallel bundles
o Connects ___________________________________________________
o Main structural support
Ligament Sprains (3 Grades)
 Grade I – some _______________________ of fibers, minimal instability, mild to
moderate pain, localized swelling and joint stiffness
 Grade II – _______________________________ and separation of the fibers, moderate
instability, moderate to severe pain and swelling
 Grade III – ______________________________ of the ligament which leads to severe
instability, severe to no pain, severe swelling, may have subluxation (joint slides out of
place)
Management of Ligament Sprain
 Results in:
o Joint effusion and ______________________, local temperature increase, pain
and point tenderness, _______________________ (change in skin color) and
possibly an avulsion fracture (pulling away from the bony structure)


Ligament has _______________________________________o Once stretched may not go back-increased scar tissue
Strengthening of muscles around the joint is critical
What are the 3 Grades of Sprains and Describe them in your own words?
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
New Vocab Words
 Diastasis
o Separation of articulating bone
 Dislocation
o A bone is forced out of alignment and stays out until surgically or manually
replaced or reduced
 Subluxation
o A bone is forced out of alignment but goes back into place
Dislocations & Subluxations
 Results in ____________________________________ ligaments & tendons
 May have avulsion fracture- attached ligament or tendon pulls a piece of bone away
 1ST time treat as a _____________________________
 “Once a dislocation, always a dislocation”
New Vocab Words
 Osteoarthritis
o A wearing down of hyaline cartilage
Osteoarthritis
 Changes in joint ________________________________lead to joint degeneration
 Commonly affects weight bearing joints but can also impact shoulders and cervical spine
 Symptoms include pain (as the result of friction), stiffness, prominent morning pain,
localized tenderness, creaking, grating
New Vocab Words
 Bursae
o Pieces of synovial membrane that contain a small amount of fluid
 Bursitis
o Inflammation of bursae at sites of bony prominences between muscle and
tendon
Bursitis
 Sudden irritation cause acute bursitis
 Overuse and constant ___________________________________ cause chronic bursitis
 Signs and symptoms include swelling, pain, and some loss of function
 Repeated trauma can lead to calcification and degeneration of internal bursa linings
Capsulitis & Synovitis
 Inflammation of the joint capsule and synovial membrane
 Caused by repeated joint ___________________________________________________
 May cause movement restriction and joint noise
Wrestler- Knee Scenario
Bone Anatomy
Anatomical Characteristics
 Bone Functions
o Body __________________________
o Organ _________________________
o Movement (through joints and levers)
o Calcium storage
o Formation of blood cells (________________________________)

Types of Bone: Classified by shape
o ________________ bones - skull, ribs, scapulae
o ________________ bones - vertebrae and skull
o ________________ bones- wrist and ankle
o ________________ bones – humerus, ulna, tibia, radius, fibula, & femur
 Bones most commonly injured
Anatomical Characteristics
 Diaphysis –_____________________ - hollow and cylindrical, covered
by compact bone
 Epiphysis – _____________________, areas for muscle attachment
(ends covered by articular cartilage)
 Periosteum - _________________ the diaphysis; dense, white fibrous
membrane



Sharpey’s Fibers- nutrient ______________________ goes
to the underlying bone
Inner layer of Periosteum- blood vessels and bone-forming
cells (osteoblasts)
Medullar Cavity- _______________________ in the
diaphysis contains marrow
Bone Growth
 Epiphyseal Growth Plate: Cartilaginous disk located ________________________ of
each long bone (growth plate) lengthens
o Injury to this can cause deformity or disruption in growth
New Vocab Words
 Osteoblast
o Bone-producing cells
 Osteoclasts
o Bone-remodeling cells
Bone Growth
 The balance of osteoblasts and osteoclasts
o ___________________________- bone growth (increase activity of osteoblasts)
o Resorption- bone destruction (increase activity of osteoclasts)
 Increased porosity- _________________________________
Bone Fractures
New Vocab Words
 Closed Fracture
o Fracture that does not penetrate superficial tissue
 Open Fracture
o Overlying skin is lacerated by protruding bone fragments
Bone Fracture
 Signs & symptoms
o _____________________________, pain, point tenderness, swelling, pain on
active and passive movements
o Possible __________________________
o X-ray for definitive diagnosis

Mechanism of Injury
o Fracture may be direct (at point of force) or indirect
o Sudden violent and forceful muscle contraction
Types of Fractures
 Greenstick: ___________________________ in the bone, adolescents
 Comminuted: ___________________________ fragments at the fracture site
 Linear: Bone split along its ________________________


Transverse: Straight line, more or less a _______________________
Oblique: Similar to spiral, one end receives torsion while the other is fixed

Spiral: ___________________ separation, foot planted and body twisted in other
direction
Impacted: Fall from a height ____________________________ the bone, need traction

Less Common Types of Fractures
 Avulsion: Separation of bone fragment ______________________ via ligament or
tendon
 Blowout: Wall of the eye orbit
 Serrated: Saw-tooth fracture line, may cause internal damage
 Depressed: Flat bones, fall or blunt trauma; a depression
 Contrecoup fracture: ____________________________ side from the point of trauma
Factors that Affect Bone Strength
 Impacted by ____________________________ and direction (weakens)
o Long bones with gradual changes are less prone to injury
 Cylindrical and _______________________ nature makes them strong
o Resistant to bending and twisting
Stress Fracture
 No specific cause but possibilities include
o ______________________ due to muscle contraction
o Altered stress distribution due to muscle fatigue
o Changes in _________________________
o Rhythmic repetitive stress vibrations

Susceptible early in training
o Increased muscular forces
o Initial remodeling and ____________________________ of bone
 Bones become weaker before stronger- SAID Principle
 Typical causes (___________________________) in sports include:
o _____________________________
o Starting initial training too quickly
o Coming back too soon after injury
o Changing training habits (surfaces, shoes,
o ____________________________/sports
etc)
without proper conditioning
o Variety of postural and foot conditions
Stress Fractures
 Early detection is _______________________________
 Bone scan is useful, x-ray is effective after several weeks, MRIs
Signs and symptoms
 ________________________ tenderness and pain (early stages)
 Pain _________________________ (later stages)
 Then constant pain and more intense, particularly at night
 Common sites:
o Tibia, fibula, metatarsal shaft, calcaneus, femur, pars interarticularis, ribs, and
humerus
Epiphyseal Conditions
 Growth plate conditions found in adolescence
 Classified by _____________________________ into five types
Apophyseal Injuries
 ___________________________ injury found in young, physically immature athletes
 Sites of origin and insertion for muscles
 Common conditions include Sever’s disease (heel) and Osgood-Schlatter’s disease
(knee)
Nerve Trauma
Nerve Anatomy
 Provides sensitivity and communication from the Central Nervous System (CNS) to/
from the rest of the body
 Basic nerve cell is the ____________________________
Nerve Anatomy
 Neuron cell body (_________________) contains large nucleus
 ______________________- branched extensions from the nucleus
o Receives neurotransmitters from other nerves
 ______________________- Conducts nerve impulses
o Output of the nerve
New Vocab Words
 Neuropraxia
o Interruption in conduction of an impulse down the nerve fiber
 Neuritis
o Inflammation of the nerve
 Referred Pain
o Pain that is felt at a point of the body other than its origin
Nerve Injuries
 Nerve cell cannot regenerate
 Nerve fibers can (3-4 mm/ day)
 Reponses Include:
o ____________esthesia- diminished feeling
o ____________esthesia- increased feeling
o ___________________- numbness or tingling
Body Mechanics & Injury Susceptibility
 Microtrauma & Overuse- Abnormal and _______________________________________
o Directly related to running, throwing or jumping
 Postural Deviations- Muscle, soft-tissue or bony _______________________________
o Results from poor mechanics