Tendinopathy

Question 1

What is the function of a tendon?

Answer 1

• Transmit force
• Create, slow, stop or prevent movement
• Store and release elastic energy

Question 2

What fraction of stored elastic energy contributes to hopping in humans?

Answer 2

One third

Question 3

What are tendons primarily composed of?

Answer 3

Collagen

• 60-85% of dry mass
• Approx 95% type 1 collagen

Question 4

What are the characteristics of collagen?

Answer 4

• Strong
• Elastic
• Highly organised
• Hierarchical structure

Question 5

What are the components of tendons?

Answer 5

Cellular component (tenocytes)

Extracellular matrix

• Fibrous (collagen & elastin)
• Non-fibrous (ground substance - proteoglycans, glycosaminoglycans, water)

Question 6

How is collagen aligned in tendons?

Answer 6

• Parallel to long axis of tendon

- Good for tensile strength not compression

Question 7

What are tendon cells called?

Answer 7

Tenocytes

Question 8

What are the characteristics of tenocytes?

Answer 8

• Produce & maintain tendon
• Spindle-shaped, spaced out, aligned
• Communicate via gap junctions

Question 9

What are the tendon coverings?

Answer 9

1. Endotenon: within tendon, conduit for blood vessels
2. Epitenon: tightly adhered to outside of tendon
3. Paratenon: Double layer sheath, loosely attached to outside
4. Synovial sheath: true tendon sheath, only at areas of high friction, double layer lubricated by synovial fluid

Question 10

Where are tendons compressed?

Answer 10

At pulleys

• Retinacula
• Annular & cruciate pulleys
• Wrap around pulley (tib post, achilles insertion)

Question 11

Why is the term tendinitis no longer used?

Answer 11

• Research explosion in the last decade
• Now called tendinopathy
• More effective treatments

Question 12

Where are tendons most likely to be injured?

Answer 12

• At either end (musculotendinous/osteotendinous junction)

- Exception: Achilles, most common in mid portion

Question 13

What are some common names of tendinopathies?

Answer 13

• Tennis elbow (extensor carpi radialis brevis)
• Golfer’s elbow (medial elbow)
• Jumper’s knee (patella)

Question 14

What tendinopathies are associated with AFL players?

Answer 14

Adductors

Proximal/distal hamstrings

Question 15

What tendinopathy almost exclusively affects women?

Answer 15

Gluteus medius

Question 16

What 4 features characterise tendon pathology?

Answer 16

• Altered number & activity of tenocytes
• Change in quantity & composition of ground substance
• Disorganisation of collagen fibres
• Neurovascular ingrowth

Question 17

What are the two theories of how tendon pathology develops?

Answer 17

1. Collagen theory
2. Cell theory
   2a. Biochemical theory
   2b. Neurovascular theory

Question 18

What is the collagen theory?

Answer 18

• Repeated loading causes micro tears

- Too much load & not enough rest = damage exceeds repair, chronic failed healing response

Question 19

What is the cell theory?

Answer 19

• Cell senses load (tensile, shear, compression)
• Attempts to adapt to increased loading
  = increased cell activity
  = altered gene expression
  = production of biochemical factors (2a)
  = increase production of ground substance
  = neurovascular growth (2b)
• Cell death/degeneration

Question 20

Why is there pain with tendinopathy (no inflammation)?

Answer 20

• Neurovascular supply
• Tenocytes produce signalling substances
• Nerves in the area have receptors for signal substances
• Ongoing debate

Question 21

What is the sequence of events for tendinopathy?

Answer 21

• Abusive loading, causes
• Cell activation
• Lots of ground substance produced, causes
• Collagen separation, causes
• Hypoxia & other factors, stimulates
• Neovessels growth, which are related to
• Pain

Question 22

What are the 3 stages of tendinopathy?

Answer 22

• Reactive (young, acute overload, direct impact)
• Tendon dysrepair (older, previous episodes, train through pain)
• Degenerative (older, long history of grumbling pain)

Question 23

What is the clinical presentation of pain for tendinopathy?

Answer 23

• Well localised
• Load-related
• Worst at start of exercise
• Eases when exercising
• Returns after cool down
• Morning pain/stiffness (achilles)

Question 24

What is the clinical presentation of change in load for tendinopathy?

Answer 24

• Unfamiliar exercise
• Type/amount
• Speed/hill running/surface
• Technique (forefoot running/minimal footwear)
• New equipment

Question 25

What are some of the differential diagnoses for tendons?

Answer 25

- Rupture (partial & total) - Traction apophysitis (especially in young boys) - Fat-pad impingement - Referred pain - Bursitis

Question 26

What are two types of traction apophysitis?

Answer 26

- Osgood-Schlatters (patellar tendon) | - Severs' (achilles tendon)

Question 27

How should pain behaviour be monitored?

Answer 27

- Pain diary | - Note what happens 24 ours after tendon is loaded

Question 28

How should tendinopathy be managed?

Answer 28

- Remove abusive load (education, modify training, physical treatments) - Adapt tendon to necessary load (systematic & progressive, beware of 24-48hr flare up)

Question 29

What is stage 1 of rehab for a degenerative tendon in an athlete?

Answer 29

- 0-3 months - Muscle strength & bulk, neuromuscular link - Start training motor pattern & addressing kinetic chain deficits

Question 30

What is stage 2 of rehab for a degenerative tendon in an athlete?

Answer 30

- 3-6 months - Tendon strength - gradually/systematically increase load - Continue to work on motor patterns & kinetic chain deficits

Question 31

What is stage 3 of rehab for a degenerative tendon in an athlete?

Answer 31

- >6 months - Sport specific - Energy storage movements every 3rd/4th day - Strength day, power day, energy storage day

Question 32

What are the characteristics of a proliferative tendinopathy?

Answer 32

- Patient younger (16-26 years) - Rapid onset generally related to load - Fusiform swelling of tendon 3-4cm - Aggravated by exercise

Question 33

What are the characteristics of a degenerative tendinopathy?

Answer 33

- Patient older (35-60 years) - Long history of symptoms - Some swelling & lumps/bump - Usually feels better with exercise, but sore the next day