WE’VE ALL HEARD OF TENDONS BUT WHAT IS A TENDINOPATHY?
Daniel Reeves (Physiotherapist – Burnie)
Has this happened to you? You step your training up or begin an exercise routine after a period of rest or de-loading, everything is going well until you wake up one day with your tendon yelling obscenities at you.
Congratulations! You now have a tendinopathy.
What is a Tendon?
A tendon is a band of fibrous connective tissue, made up of collagen that attaches muscle to bone. Tendons transfer force from muscles to bones and can become painful when worked too much.
What is Tendinopathy?
Tendinopathy is a general term for a tendon injury. You may have heard of ‘tendonitis’ which was previously the common term used. Tendinopathy is now the preferred term for this type of injury as the ‘itis’ infers inflammation of the tendon and research has shown that there may not be an inflammatory process occurring.
In most cases tendinopathy is an overuse injury and results in pain and reduced function. Examples include achilles, patella and hamstring tendinopathies.
Where will I feel pain?
Pain is usually very localized (you should be able to point with one finger to the site of pain) and can occur in the mid-tendon or where the tendon joins to bone. Pain is typically load dependent so higher load activities like running and jumping will increase pain.
Fig1. Examples of where you may feel pain if you have tendinopathy
What Causes Tendinopathy?
The cause of tendinopathy has been linked to repetitive high loads (repetitive energy storage & release) above the tendons capacity. Simply, the load placed on the tendon exceeds its capacity/strength. Changes then occur in the tendon structure that result in pain and reduced exercise tolerance. These changes include an increase in tendon cells (called tenocytes), disarray of the tendon structure (e.g. collagen fibres) and an overall reduction in tendon capacity and strength.
What Is Load?
As mentioned, tendinopathy is usually the result of overuse and is related to load. Load can simply be thought of as a combination of intensity, frequency, type and duration of exercise. Tendons hate changes in load, so when load is acutely increased a tendon can become irritated and painful. This usually occurs by doing more than what your tendon is used to. For example, going from ‘couch potato’ to running 100 stairs/day.
Tendons can also become irritated when you overload them constantly for a long period of time. For example, excessive basketball or netball training, week after week, involving lots of repetitive jumping and landing can cause a tendinopathy of the patella tendon, the tendon below your knee cap.
What Is Tendon Capacity?
Capacity of a tendon can be thought of as a bucket. You have a limited capacity to which you can fill the bucket (load the tendon) before it overflows. The bigger the bucket, the bigger your tendons capacity for load. If you overflow the bucket, by overloading the tendon, pain occurs.
You can increase your tendons capacity (size of your bucket) through gradual training progressions and load training so you can withstand higher loads. A bigger bucket can hold more water, a tendon with bigger capacity can withstand more load.
What Are High Tendon Loads?
High tendon loads are loads encountered when the tendon acts as a spring. It stores energy and releases it fast. For example, high tendon loads occur during jumping, landing, sprinting and change of direction movements. This is why tendinopathies are common in sports that involve these movements.
Low tendon loads are slower movements and can include heavy resistance training. For instance, while the weight during a back squat may be heavy, the tendon load is relatively low compared to the high tendon load during a squat jump.
What Are The Stages of Tendinopathy? The Tendinopathy Continuum
There are 3 Stages of tendinopathy and a tendon can move between these stages as a response to load and rest.
- Reactive: This is normal tissue adaptation where the tendon responds to overload. The overload causes the tendon to thicken and increase stiffness in an attempt to cope with loads. Reactive tendinopathy usually occurs in younger people (15-25yrs) and is common in athletes. Onset is rapid and related to a period of acute overload. A short period of rest may be required to offload the tendon and allow it to return to its normal state. If excessive load is continued, tendon dysrepair can occur.
- Dysrepair: There is an attempt of tendon healing, similar to the reactive tendinopathy but a larger breakdown of the tendon structure occurs.
- Degenerative: Usually occurs in older people (30-60yrs) as a result of chronic excessive overload which cause further structural changes to the tendon and even areas of cell death. These changes weaken the tendon, increasing the risk of rupture. Capacity for reversing the changes is small. People in the degenerative stage usually have a long history of symptoms.
Reactive on Degenerative: A reactive on degenerative tendinopathy occurs when you flare up the ‘normal’ part of your tendon due to excessive loading. Think of your tendon as a donut. The hole is the affected part of the tendon and the donut itself is your ‘normal’ tendon.
Here’s a video that explains the above https://www.youtube.com/watch?v=gGicPXm3n30
How Long Will It Take To Get Better?
Recovery can be a slow process that can take months of individualized rehab.
How Do I Get Better?
Tendons respond to load. Therefore, you need to follow a gradual progressive loading program to increase your tendons capacity for load.
Load management is vitally important in the rehabilitation of tendinopathy. It is important to reduce unnecessary, detrimental loads that make your pain worse but avoid complete rest. Complete rest is not advised as your tendon will become weaker which will only further reduce your tendon’s capacity (size of your bucket) and lead to further decreases in function.
It is important during rehab to monitor your symptoms/pain. 24 hour behaviour is a good guide of day to day tendon load i.e. how you feel today indicates the response to the load from yesterday. For example, if your pain is worse today, the load yesterday may have been too high. As such, you would reduce load to a manageable level that does not increase pain the next day.
There are 4 phases in tendinopathy rehab
- Pain Relief: This phase involves isometric exercises that load the tendon and increase its strength and capacity. Isometrics can also reduce pain. The recommended dosage is to build up to 4-5 sets of 45sec isometric contractions at 70% maximum voluntary contraction, 4xdaily. For an achilles tendinopathy an example would be an isometric calf raise.
- Strength: Isotonic strength exercises 2-3x/week. On off days perform isometrics. 4 sets of 6-8 reps. For example single leg calf raises or smith machine calf raises.
- Energy Storage: Low level plyometric exercises every 2-3 days. For example, skipping or moving fast upstairs. Recovery and load monitoring is important. Continue strength exercises during this phase.
3. Sport Specific/Elastic Function (Energy Storage and Release): Sport specific tasks and higher level plyometric exercises. Some examples include squat jumps, single leg hops, and change of direction drills.
The progression through these stages should be overseen by a Physiotherapist or Exercise Physiologist as they can help advise when you can progress to the next phase and answer any questions you may have relating to your recovery.
The goal of rehab is to build up your tendon capacity and strength so that your tendon is strong enough to cope with the load/s you impose on it.
It is also important to address strength deficits up or down the kinetic chain throughout your recovery. For example, if suffering an achilles tendinopathy, strengthening the glutes and quadriceps could be helpful.
How to Reduce Your Risk?
Tendons like to be treated nicely with small incremental increases in load that they can adapt to gradually. This means easing in to a new exercise program or pre-season training program and increasing load gradually to avoid spikes in load. Ensuring adequate recovery between loading is also important. A strong foundation of tendon and muscle strength will help to reduce your risk by increasing the capacity of your tendon.
I hope this has answered some questions you may have regarding tendinopathy and tendon pain. If you think you may have a tendinopathy and would like some help getting back on track, call our clinic and book an assessment
If you treat your tendon with some love, it will love you back!
References
http://bjsm.bmj.com/content/50/19/1187
Cook et al., (2017). Revisiting the continuum model of tendon pathology: What is its merit in clinical practice and research? BJSM, 50, 1187-1191.
http://bjsm.bmj.com/content/43/6/409
J. Cook, C. Purdam (2009). Is tendon pathology a continuum? A pathology model to explain the clinical presentation of load-induced tendinopathy. British Journal of Sports Medicine. Vol 43, Issue 6, 2009.
Rio, E. (2016). Tendon – Let’s Get Excited