Muscle Contusions/strains/tears/weakness

Question 1

Stages of healing

Answer 1

Inflammation
Repair
Remodelling

Question 2

Inflammatory stage of healing

• Duration
• Key features

Answer 2

24hrs to 3-4 days

• Myofiber rupture and necrosis
• Hematomas
• Inflammatory cell reaction

Question 3

Repair stage of healing

• Duration
• Key features

Answer 3

5-14 days

• Phagocytosis of necrotic fibers
• Regeneration of myofibers
• Formation of scar tissue
• Capillary ingrowth

Question 4

Remodelling stage of healing

• Duration
• Key features

Answer 4

14-21+ days

• maturation of myofibers
• Contraction and organization of scar tissue
• Recovery of function

Question 5

Contusion cause + result

Answer 5

External forces leading to bleeding in deep muscle regions

Question 6

Contusion Rx in first 48hours

Answer 6

PRICE
No HARM - Heat, alcohol, running, massage
Put muscle on as much stretch as possible (dont want to heal in shortened position)
Crutches if necessary
gentle pain-free ROM/stretch
Progressive exercise after acute phase

Question 7

Contusion Recovery time Grade 1-3

Answer 7

Grade 1 - 2-3 weeks
Grade 2 - 4-6 weeks
Grade 3 - 6-8weeks

Question 8

Contusion complications

Answer 8

o Compartment syndrome  check capillary refill and sensation, muscle strength
o Myositis ossificans  formation of bone within muscle, suspect if haven’t improved after 2-3 wks

Question 9

Difference between cause of an acute and a chronic muscle strain

Answer 9

Acute = excessive lengthening 
Chronic = over exertion

Question 10

Where to the majority of muscle strains & tears occur

Answer 10

In biarticular muscles at the muscle-tendon junction

Question 11

During what motions do the majority of muscle strains & tears occur

Answer 11

During eccentric loading or high intensity, explosive activities

Question 12

When are you mostly likely to strain or tear the long head of biceps femoris

Answer 12

During the terminal swing phase of high speed running

Question 13

When are you mostly likely to strain or tear semimembranous

Answer 13

Concurrent hip flexion and knee extension

Question 14

Key physiological and clinical features of a grade 1 muscle strain

Answer 14

• Microscopic tearing

- Pain/tightness no weakness

Question 15

Key physiological and clinical features of a grade 2 muscle strain

Answer 15

• Partial, macroscopic tearing

- pain and structural change (laxity, decreased strength)

Question 16

Key physiological and clinical features of a grade 3 muscle strain

Answer 16

• Complete tear

- Painless and weak, may see lumb

Question 17

Muscle strain Rx

Answer 17

• Acute/inflammation: PRICE, Crutches if LEs
• Repair: modalities (US, IF), DTF, strength, stretching
• Remodelling: Strength (increase load + velocity), stretching (static/dynamic

Question 18

When is RTP safe in a muscle strain

Answer 18

• Symmetrical muscle length, strength, power, no s/s, core control
• Completion of progressive functional progression + sport specific drills + practice session

Question 19

Laceration Rx

Answer 19

• Requires surgical repair
  Inflammation - optimize gait so scar tissue aligns properly
• Repair phase - Gradual ROM + strength
• Promote remodelling by gradually increasing the load and velocity
• Careful of muscle force going through sutures

Question 20

When does DOMS occur

Answer 20

72 hours after unaccustomed exercise

Question 21

What causes DOMS?

Answer 21

Possible due to local nerve ending response to altered environment: acid, pH, swelling, inflammation

Question 22

Doms Rx

Answer 22

• Light activity  cycling, walking, ankle pumps
• Massage/bath
• Avoid anti-inflammatories if possible