Updated: May 5, 2022
Achilles Tendinopathy Cause
Achilles tendinopathy refers to degradation of the achilles tendon. You may be more familiar with the term achilles tendonitis, as that was the commonly accepted name for decades. However, researchers have shown that this is a misnomer. Tendonitis refers to inflammation of the tendon, which does occur in tendinopathy, however, it is not the main cause of damage and symptoms. Think of hitting your finger with a hammer. The damage and pain is from the trauma from the hammer, the swelling in your finger is just part of that process. If you went to the doctor and they simply treated the swelling in your finger, they would be missing the real issue. In healthcare, we spend too much time worrying about inflammation. Swelling can be a marker of damage, but it is just a part of the bigger picture.
We also have a better understanding of the nature of tendinopathy. First, your tendon becomes reactive, meaning it is sensitized. This occurs from some initial damage or stimulus that the tendon is unable to handle. Imagine not running for months and then running 5 miles. You may not have done any serious damage, but your tendon is irritated. If you kept irritating the tendon, then there would be some breakdown. This is typically microscopic tears. It is important to remember that small tears are normal parts of everyday life, in fact it is how we grow muscles. Unfortunately, the achilles tendon gets very poor blood flow compared to other parts of the body, leading to slowed healing and recovery. It is also the largest tendon in the body and plays a significant role in any standing activity, particularly running or jumping.
It is important to remember that tendons are the connection between muscles and bones. The achilles tendon connects your calf muscles, the gastrocnemius and soleus, to your heel bone or calcaneus. Any time you contract your calf muscles by raising your heel, you are tensing the tendon. Conversely, lifting your toes actually stretches the tendon.
Achilles Tendinopathy Symptoms
Achilles tendinopathy symptoms usually involve pain localized to the tendon. Pain can occur with raising the heel, but it can also be present with stretching the calf muscles, as this stretches the tendon. The pain can be located at either the midpoint of the tendon, or the insertion where it meets your heel bone. There can be some swelling that is visible at the tendon, particularly if you have chronic tendinopathy. You may also notice some thickening of the tendon if you feel it with your fingers.
Pain is typically worse first thing in the morning. This is because you have probably not moved your foot throughout the night, which leads to stiffening of the calf and achilles tendon. Also, most people sleep with their toes pointed downwards, which shortens the tendon. The first few steps out of bed introduce a stretch that has not been felt for a few hours and can be painful and tight. Pain is also worse with ballistic movements such as running or jumping. Sometimes, the pain can decrease with prolonged activity as blood flow increases, but the pain will return after the activity along with tightness.
Diagnosing achilles tendinopathy is usually done by discussing symptoms and palpation of the tendon. It will typically be painful to touch the tendon, particularly when it is irritated. X-rays can be used to examine the bony structures and ensure that fractures are not present. An ultrasound is typically the most effective imaging to study the tendon, as it will show any damage and is minimally invasive. An MRI can be used to look for swelling and other soft tissue damage in the area.
Achilles Tendinopathy Treatment
Treatment for achilles tendinopathy can be difficult depending on the severity of symptoms. Less severe symptoms can be managed with workload changes and exercise interventions which will be discussed in the next section. Some other treatment options can include a night splint to allow for stretching of the achilles overnight. Research has shown that night splints can be helpful in acute situations in some cases. I will usually have clients try a night splint if they desire, but some people find them uncomfortable and not beneficial.
A heel lift is another option that is commonly prescribed. The thought process is to limit the stretching of the achilles tendon by decreasing how far the heel can drop. Imagine wearing high heels and how little your calf stretches. Heel lifts can be helpful to temporarily offload the tendon while it is healing before gradually re-introducing normal heel depth in shoes.
Orthotics can be helpful depending on the individual. There is conflicting evidence regarding the role of pronating feet in regards to achilles tendinopathy. Biomechanically, it makes sense that a collapsed arch, as shown below can lead to stress on the achilles tendon as it is stretched in different planes. A study by Wezenbeek, et al. actually showed that overpronation led to decreased blood flow in the achilles tendon. Once again, it can be worth trying over the counter orthotics to determine if there is any benefit in the individual.
Wearing a walking boot can also be prescribed for achilles tendinopathy. The theory is that preventing movement of the achilles tendon will allow for healing to take place. Anecdotally, in cases where there is fear of a significant rupture, this is understandable. However, you are limiting blood flow and movement to the calf and achilles which creates a decrease in mobility and strength once the boot is removed. This is an aggressive treatment strategy which may be utilized if other techniques are not effective.
Corticosteroid injections can be utilized to decrease inflammation. This may be beneficial to give a window for exercise and physical therapy to provide some strengthening to the calf and achilles tendon. Repeated steroid injections can lead to breakdown of the tendon and they are typically avoided.
Finally, there are various surgical procedures that can be utilized to treat achilles tendinopathy. The damaged portion of the tendon can be surgically removed or sutured to allow for healing. Also, part of the calcaneus can be removed to decrease tension on the tendon. These options are very rare and only reserved for achilles tendinopathy that has failed all other treatments.
Achilles Tendinopathy Physical Therapy
As I mentioned above, physical therapy is the first line of treatment when it comes to achilles tendinopathy. The initial step should involve decreasing stress on the tendon if appropriate. A period of relative rest may be required to allow healing to occur. This should not involve stopping all activity if possible, but limiting or spreading out exercise. For example, instead of walking for 3 miles at a time, several 1 mile walks may be better tolerated.
It is also important to study overall workload. If you recently ramped up your running volume or intensity to prepare for a race or sport season, you may have simply put too much load on the tendon too quickly. Reducing the load and slowly building back up may be all that is needed.
It is important to examine the entire body when dealing with any injury. A decrease in hip mobility or strength can play a role in stressing the achilles tendon and ankle with running or jumping. While the primary focus should be on the injured tissue, it would be a waste to not assess the whole body and look for any weak links.
Manual therapy does have some benefit in cases of achilles tendinopathy. Soft tissue restrictions of the calf muscles can put tension on the tendon due to guarding. Trigger point dry needling can be an effective treatment in this case, as it allows trigger points to be addressed directly and efficiently. Joint mobilizations of the ankle joints, primarily the talocrural and subtalar joints may also be appropriate.
Achilles Tendinopathy Exercises
Exercises for achilles tendinopathy follow a typical progression of less range of motion and less load initially followed by a gradual progression. Isometrics where the muscle does not move through any range of motion can be helpful at first. Simply standing with your heel off of a step can be a good starting point, working up to repetitions of 45-60 seconds. You can also do this with only one foot to increase the load. Another exercise option is a lunge with a floating heel. Your forward foot is placed on a weight or small step with the heel off of the step. You perform lunges while keeping your heel in the air. This provides a dynamic lower body workout with an isometric calf contraction. The picture below courtesy of byanymeansbball.com provides a great visual.
From here, you can progress the range through which you are loading by doing calf raises on the ground and eventually off of a step. Research shows that insertional achilles tendinopathy does not respond well to heel raises off of a step. If your pain is located close to your heel bone, you may want to avoid aggressive heel raises off of a step and stick to flat ground. As you progress, you can move to a single foot and then begin holding weight. The goal at this point is to hold as heavy of weight as possible while moving slowly to control the movement. I have discussed this before, but you should try to keep your weight on the first two toes to avoid rounding your ankle. This will increase your calf engagement as shown in the picture below.