Tendinitis? Tendinopathy? What is tendon pain and how to treat it?

Jesse Castillo

September 6, 2021

TENDINOPATHY UPDATE

With the stop start nature of community sport and gym access with lockdowns the past year, we have seen a large number of tendon injuries. Tendon’s are load dependent where too much load can cause injury and conversely reductions in load can lead to injury when activity recommences. In Victoria, we are fortunate to have world class researchers and clinicians who specialise in tendinopathy care to guide best practice in an ever-evolving space. As a result, prior to COVID-19 restrictions, I attended the Latrobe Sports and Exercise Medicine Research Centre (LASEM) Head to Toe Symposium in late 2019 when they were able to deliver their last face to face conference on tendons. The symposium had great insights into updates regarding both upper and lower limb management.

General update

Tendinitis or Tendinopathy?

Previously, tendon pain used to be referred to as  “tendinitis”,  however the role of inflammation in the tendon is actually very low. Current research has shown that the levels of inflammatory markers is actually very low and likely not to be a primary driver of pain or pathology. Hence why tendinopathy has be coined as the correct terms for tendon pain.

Tendon Continuum

The tendon continuum model provides great insight into staging tendinopathy based on the changes within the tendon (Cook & Purdam, 2009). This continuum of tendon pathology has been cited in over 250 publication since its been released.  Although the continuum was based on evidence from lower limb tendons, it has been adapted for rotator cuff pathology in shoulders as well. Tendon pain fits in the continuum model in two main categories, as described below with an intermediate stage.  The model below suggests that the tendon can move up and down this continuum.

1. Reactive tendinopathy

  •  This is the 1st stage on the tendon continuum and is where there is an initial overload of the tendon

2. Tendon disrepair

  • This is the intermediate stage between reactive tendinopathy where it can progress if the tendon is not properly loaded to regress back to the normal state.

3. Degenerative tendinopathy

  • This is the final stage on the continuum where there is now disorganisation on the matrix. On imaging, there are areas of this degeneration scattered throughout the tendon and mixed in with the normal tendon.
(Cook, 2009)
(Cook, 2009)

Knowing this model helps guide the rehabilitation journey and hence why physiotherapy management is targeted at improving the healthy tendon and why pain/function can improve without an changes to imaging results.

Imaging Updates

The exact cause of pain in tendinopathy is unclear. There is a disconnect with pathology on imaging and pain (Ryan, 2015). Imaging is able to support the diagnosis of tendinopathy, however there is also a lot of false positives, which means that people without tendon pain may have tendinopathy findings. This news is great for individuals with painful tendinopathies as it shows that you can function pain free with the appropriate loading and management.

Repeat imaging is also not indicated over the course of rehabilitation as the imaging does not appear to change considerably in tendon pathology with rehabilitation, even if pain improves as described above. Therefore with any rehabilitation, pain and function should be your guide and not imaging.

Are all tendons the same?

More and more research is evolving to show that not all tendons are the same (Bohm, 2015).  If you look at the rotator cuff musculature, they are not a prime mover like the achilles and patella tendons.  The rotator cuff muscles have other muscles that can assist in shoulder movements and arm movements, whereas the Achilles and patella tendons only provide the specific movement for the ankle and knee respectively. Likewise, when looking at how tendons respond to pathology, each react differently. Some tendons like to get thicker with an onset of reactive tendinopathy such as the achilles, while other tendons like to get thinner like the rotator cuff, tibilalis posterior, gluteal tendons. Therefore, management and rehabilitation will vary depending on which tendon it is.

When it is not a tendinopathy?

Tendon pain is usually localized pain with minimal referral and a patient should be able to point to their pain with one finger. Although there may be a slight spread of pain in insertional tendinopathy, whereby the tendon closely communicates with the bursa and fat pad and these may also be contributors to pain. Tendon pain is usually activity related, worse in the morning, takes time to warm up and is worse after activity. Therefore, an assessment from a health professional is very important to differentiate tendon pain from other sources of pain, and in turn, this will dictate management.

Treatment and Management – How can physios help?

Tendon loading, kinetic chain strengthening, managing load and education are the primary strategies in managing tendinopathy. Research studies have shown strengthening programs to be beneficial in tendon pathology management. Myles et al., (2019) looked at the rate of change/improvement of pain and function in mid portion Achilles tendinopathy with exercise. The study shows that pain and function can improve as early as 2 weeks, then peaked at 12 weeks after a loading program. These findings are interesting as the tendon structure does not change at 2 weeks and significant muscle hypertrophy is not seen until after 4 weeks, demonstrating exercise may have benefits in both pain management and musculotendinous unit physiological changes at a later stage. Seen below are a list of key exercises groups that are required in lower limb tendinopathy management. 

1) Isometric loading

Isometrics can be an effective initial form of exercise to enable strengthening to commence when the tendon is irritable. For the tendon to improve in strength and to tolerate demands of sport all stages of tendon rehab need to be completed including heavy slow loading/ strength training, kinetic chain strengthening and plyometric/ sport specific loading.

Seated calf raise
Spanish Squat

2) Muscle and tendon Strength including kinetic chain

Strengthening exercises that target strength and hypertrophy of the musculotendinous unit are a priority in tendon rehab. Later stage rehab will incorporate exercises to build strength of the kinetic chain.

Strength/ Heavy slow loading: Squats
Kinetic chain- Step up with knee drive

3) Plyometric loading

Plyometrics will target explosive strength of the muscle and tendon and be based on the sport specific demands. These can by quite provocative so need to be implemented with care.

Plyometric/ explosive strength: Pogo

Summary

The take home message is that exercise based rehab is the best treatment for tendon pain. A progressive program that starts with a strength program and progresses through to exercises that allows the tendon to act like a spring and also include endurance aspects to give required loads on the tendon. Therefore it is important to see a qualified physiotherapist to guide your individualised rehabilitation.

About the Author

Jesse Castillo has special interests in exercise based rehabilitation, lower limb tendinopathy and overload issues, acute and chronic knee issues and sports concussion. Jesse works with local football teams including his roles as head physio at Leopold FC. Jesse is a level 1 ASCA Strength and Conditioning coach, and prioritises staying up to date with current research, including his current involvement in the Latrobe University SUPER knee study