What is a Tendinopathy (previously known as tendonitis)

What is a tendinopathy?

Tendons are the structures that connect muscles to bones. A tendon’s role is to store energy and release the energy and act as a spring. A ‘healthy good tendon’ is able to develop a greater force of development/power. Think of this tendon like a race car having stiff and tight suspension (the car wants less bounce).

Pain and pathology in a tendon is known as a tendinopathy. This term encompasses an acutely injured tendon that has a minimal amount of inflammation. A tendon becomes tendinopathic when the tendon is subjected to higher loads than it can withstand (excessive force) or has insufficient time to recover.

Figure 1: Tendinopathy and tendonitis - Physio Frenchs Forest, Physio Macquarie Park

Figure 1 shows that if an individual does repeated training or exercise with rest periods that are too short, then there is degradation to the tendon. Tendons require 36-48 hours of recovery following intense exercise.

Factors that increase the risk of developing a tendinopathy include:

There’s an increase in compressive, tensile or shearing loads on the tendon. These include loads include:

  • Increase in speed of running/walking

  • Increase in distance running/walking

  • Increase in the number of stairs or hills running/walking

  • Increase in kicking, jumping or hopping

  • Increase in training volume

  • Return to training after an extended break

  • Poor flexibility

 

What happens when a tendon is damaged and causes a Tendinopathy?

1. Increased Tenocytes – There are more produced that are less developed and become rounded. This results in less tensile (stiff strength).

2. Increased water content – Increased proteoglycans and glycosaminoglycans. This reduces the intrafilamentary sliding potential of the tendon.  

3. Change in collagen disorganisation (More type 3 than type 1) – More type 3 fibres are produced, the fibres are less parallel, and there is accumulation of ground substance.

4. Neovascularisation – Hypervascularisation and increase in blood vessels.

Figure 2: Tendinopathy and tendonitis - Physio Frenchs Forest, Physio Macquarie Park

What are the signs and symptoms of a tendinopathy?

  • Localised pain over the tendon

  • Possible tendon thickening: This is due to an increase in water of the tendon not inflammation

  • 24-hour response: Morning pain and stiffness following exercise

  • Mechanism: Sudden change in training load

  • Proportional load-pain relationship: The higher the training load, the higher the pain

  • Worse after exercise: This could be immediately, that night or the next day

  

Is the tendon inflamed?

Is has been shown that there is a very low number of inflammatory markers and they are likely to not be a primary driver of pain or pathology.

 

What causes the pain in a tendinopathy if there is only a small amount of inflammatory markers?

There is an increase in the following (these chemicals cause pain):

  • Substance P

  • CGRP

  • Cytokines

  • Ground substance

  • Lactate

 

What other risk factors increase the risk for developing a tendinopathy?

  • Age – As we get older we have greater type 3 fibres, reduced elastin and more interfascicular adhesions

  • Systemic – Diabetes, gout, rheumatological conditions

  • Previous tendinopathies – Earlier fatigue, loss of tendon stiffness, increases tendon strain

 

How can I make my tendon stronger, and improve my tendon pain?

When we contract a muscle connected to a tendon with enough force, the tendon will stretch slightly. The cells within the tendon can sense this force, and respond by making more proteins to make the tendon stronger.

What exercise is required for tendinopathies?

The tendon needs to be targeted specifically with the right exercise to ensure adaptation.

Figure 3: Tendinopathy and tendonitis - Physio Frenchs Forest, Physio Macquarie Park

Should you rest a tendon or exercise the tendon?

There is a ‘goldilocks zone’ for the optimal amount of tendon stretch and load. Too little or resting won’t be enough stimulus and too much will compromise the tendon further.


Principles of Rehabilitation for tendinopathies:

1. Education: Know the condition and its prognosis  

2. Loading advice: Modify training load and implement a 24-hour pain monitoring model

3. Address the kinetic chain deficits: Hip, knee and ankle range of motion

4. Exercise based loading: Prescribe tendon specific exercises.

 

Key Take-Away Points:

1) Pain and function should guide rehabilitation, not imaging

2) Optimal load management is key – Not too much, not too little, just the right amount  

3) Gradual strength loading is key. Tendons love heavy slow resistance exercise in the long-term.

4) Signs and Symptoms of tendinopathy: Tendinopathies will typically get better with a warm-up, worsen after loading and feel horrible the next day.

5) Consider the kinetic chain: Capacity deficits above the tendon or the other leg could be key contributors

See our expert Physiotherapy team at Frenchs Forest and Macquarie Park!

Reece Jonestendonitis, patella tendinopathy, glute med tendinopathy, achilles tendinopathy, running physio, running injury