MSK Injuries Flashcards
(105 cards)
difference between strain vs sprain
- strain: Injury involving the muscle or muscle-tendon unit
- sprain: Trauma to the ligaments that connect bones of a joint
MC strain
Distal muscle tendon junction injury MC
MC sprains
ankle, knee, and wrist during sports activities
strains are MC in muscles attached to ?
2 joints
MOA of strain
Forceful eccentric loading of the muscle
Ex: running, jumping, kicking
MOA of sprain
Joint is overextended; ligament is overstretched
ligament sprain is uncommon in what pt demographic? (2)
why?
children and older adults
They have weaker bones = avulsion or growth plate fractures
RF for strains and sprains (9)
- poor ergonomics
- environment
- increased age w/ reduced physical activity
- deconditioned or unstretche muscles
- specific activities
- overuse
- body habitus
- fatigue
- previous injury
Pts often report a popping, snapping, or tearing sensation at the time of the event
followed by pain, swelling, stiffness, and difficulty bearing weight/reduced ability to use the extremity involved
Bruising + discoloration may appear within 24-48 hours
hx of what dx?
strains & sprains
- Asymmetric swelling, tenderness, and ecchymosis of injured area
- Visible and/or palpable defect may be seen/felt
- Pain with active and passive flexion of the muscle
- Loss of active muscle contraction to move joint→ complete rupture of the muscle
PE of what dx?
muscle strain
- Asymmetric swelling, tenderness, and ecchymosis of injured area
- Pain with active and passive ROM
- Joint instability/laxity
- Special tests may be beneficial
PE of what dx?
ligament sprain
muscle strain grading
- Grade 1: Tear of a few muscle fibers (< 10%), fascia intact
- Grade 2: Tear of moderate amount of muscle fibers (10-50%), fascia intact
- Grade 3: Tear of most/all fibers (50-100%), fascia intact
- Grade 4: Tear of all muscle fibers (100%), fascia disrupted
ligament sprain grading
- Grade 1: Mild; a tear of only a few fibers of the ligament; no joint instability
- Grade 2: Moderate; partial tear of the ligament; some laxity with stress maneuvers
- Grade 3: Severe; complete tear of the ligament; joint laxity with stress maneuvers
how to dx strains/sprains
- Most often clinical
- Labs and imaging are usually not necessary - X-ray if high concern for fracture
indications for XR for strains/sprains
- Positive “Ottawa Ankle Rules”
- Can be generalized to other joints - Worsening pain/swelling with appropriate management
- Persistent pain/swelling after 7-10 days of appropriate management
ottawa ankle rules for ankle sprains
- pain at the medial malleolus or along distal 6cm of posterior/medial tibia
- pain at lateral malleolus or along distal 6cm of posterior fibula
- inability to bear wt immediately and for 4 consecutive steps in ER
ottawa ankel rules for foot sprains
- pain in midfoot and at base of 5th metatarsal
- pain in midfoot and at navicular bone
- inability to bear wt immediately and for 4 consecutive steps in ER
which dx modality is used to confirm or grade strains/sprains?
indications?
MRI
- suspected rupture or severe pain
- surgical intervention is likely
Healing process is divided into 4 phases:
strains + sprains
- hemostasis
- inflammatory
- proliferative
- maturation
- Onset → immediately after injury
- Platelets aggregate and release cytokines, chemokines, and hormones
- Vasoconstriction - limits bleeding into affected area = temp skin blanching
- Clot formation occurs
which phase of healing process
hemostasis
- Onset → immediately after injury
- Results from tearing of the myofibers, ligament fibers, and microvasculature
- Bleeding and necrosis of the soft tissue = inflammatory cascade
- Homeostasis of fluid balance is disrupted resulting in swelling
- Capillaries dilate and become more permeable → increase in blood transmission into the extravascular space (bruising) & increase in the concentration of local inflammatory mediators
which phase of healing process?
how long does this last?
Inflammatory/Destruction Phase (0-72 hrs post injury)
- Granulation tissue is formed - Collagen deposition occurs
- Neovascularization occurs at the injury, supporting tissue healing
- Inflammatory mediators are reduced
which phase of the healing process?
how long does this last?
Proliferative/Reparative/Fibroblastic Phase (72 hrs - 3 wks)
Collagen and myofibers increase in number, strength, and organization
which phase of healing process?
how long does this last?
Maturation/Remodeling Phase (3 wks - 2 yrs)
management goals during Hemostasis / Inflammatory Phase (day 0-3)
→ Protection / compression of the injured area and rest
→ Control pain and swelling = ICE!