Tendinopathy is a condition in which there is degeneration of the tendon typically caused by overuse or overloading of the tendon. It is characterised by pain localised within the tendon, mild swelling and a decrease in function. Our tendons are like thick rubber bands which attach muscle to bone. This thick band can be stretched, compressed and transmit forces along its length. When we load our tendon, it is important that our tendon has the capacity to take that load. Like muscles, our tendon’s capacity to take load is determined by the amount of load we put on it on a daily basis, however, when we are introducing new loads we need to allow the tendon enough time to adapt. If we load the tendon too quickly, the tendon will attempt to adapt to the new load, however, it does this ineffectively by changing its structure. With this continued increased loading, cells in the tendon begin to die and the tendon itself will begin to degenerate.
What are the common symptoms?
People with tendinopathy often experience:
- Pain and stiffness confined within the tendon
- Pain at the start of activity which gets better as activity continues but returns once activity has ceased or the following morning.
- Gradual onset of pain typically following an increase in activity/loading, such as a new training program or returning to sport after a period of inactivity.
- A decrease in function of the affected tendon
The Three Stages of Tendinopathy
The three stages of tendinopathy act more like a continuum starting from a normal tendon and progressing to a tendon in which its structural integrity is compromised.
This is the acute stage of tendinopathy in which a normal tendon has been exposed to an increased load over a short period of time without any time for adaptation of the tendon. In response, the tendon thickens to reduce stress and increase stiffness. During the reactive tendinopathy stage, the tendon has the potential to revert back to a normal tendon if there is enough time for the tendon to adapt or if the load is reduced.
This stage is a progression of the reactive tendinopathy stage where the tendon has been exposed to continued increased loads without sufficient time to adapt. In this stage, there is an increase in vascular and neuronal tissue growth in the tendon and the tendon matrix begins to break down. In this stage, there is still the potential for some of the tendon to revert back to the reactive tendinopathy stage with the management of load and exercise.
From the tendon dysrepair stage, continual increased loading of the tendon can lead to the degenerative tendinopathy stage. In this stage cells within the tendon begin to die and the tendon starts to degenerate. Due to the presence of cell death, there is little capacity for reversibility in this stage.
It is important to note that while a part of the tendon may be in the degenerative tendinopathy stage, the surrounding tissue may only be in the reactive tendinopathy stage and still have the potential to revert to a normal tendon. This is called a reactive-on-degenerative tendinopathy. This is where we look at treating the ‘doughnut’, not the ‘hole.’
While tendinopathy is painful when engaging in activity, it is important not to completely offload the tendon. With rest, the pain may settle initially, however, when activity is resumed the pain will return. This is because tendons need load to maintain their structure. Instead of completely resting the tendon, we need to look at modifying the activities we do in order to reduce the load on the tendon and allow it time to adapt. To know if the load is appropriate, pay attention to how the tendon responds, particularly 24-48 hours after activity, as tendons often have a delayed response.
Isometric exercises are introduced in the early stages of rehab to reduce pain. With isometric exercises, the muscle length is maintained while it is being loaded. For example, holding a weight in your hand with your arm stretched out in front of you is an example of an isometric exercise. Compression of the tendon should be avoided with these exercises and therefore should be held around mid-range.
Once isometric exercises are pain-free and the modified load is no longer causing pain or stiffness within the 24-48 hour period, isotonic exercises are commenced. Isotonic exercises are when the muscle lengthens and contracts while loaded. Once again compression of the tendon should be avoided therefore exercises moving within the mid-range of the muscles are ideal. It is important to start with lighter loads and progress the load slowly so as to not overload the tendon.
As the symptoms begin to reside and the tendon load capacity progressively improves activities may also be increased in a staged process. The ideal progression is a 10-15% increase in activity each week. This is a slow progression that allows ample time for the tendon to adapt to the new load.
In this stage exercises are progressed through the full range of motion and compression of the tendon can begin. It is important to also start training the tendon for energy storage as this is a normal function of any tendon. For example exercises such as stepping down off a box, hopping or sprinting for an Achilles tendinopathy.