The Grumpy Achilles Tendon

Used to be called Achilles tendinosis or tendinitis. Medically called Achilles tendinopathy or Achilles tendon pain.

Clues or common symptoms? 

• Pain around the tendon between your calf and the back of your heel bone on palpation and during high-energy movements like running, hopping, and jumping (ICON 2019: International Scientific Tendinopathy Symposium Consensus: Clinical Terminology). Tendon pain often does not reflect the amount of predicted force going through a tendon (Patterns of movement-evoked pain during tendon loading and stretching tasks in Achilles tendinopathy). E.g. sprinting might not be worse than hopping. So don’t think “more pain equals more damage.” Tendon pain will often start worse and then reduce after “warm-up” throughout springy activities and can be sore again in the evening and the day after. Some might notice the tendon getting thicker. Other conditions with similar presenting symptoms, such as a calf muscle strain, nerve pain, or bony/joint irritation at the back of the ankle joint, should be ruled out as management and expectations for recovery for these conditions are different from Achilles pain. Pain around the Achilles but during low-energy activities like walking or just moving your ankle might indicate the tendon packaging, sheath, or paratenon of the Achilles tendon is irritated, which can change how to manage the condition. Imaging is unnecessary for diagnosing Achilles tendon pain and only necessary if we suspect another diagnosis that isn't responding well to high-quality physiotherapy management (Imaging and its role in tendinopathy).

How common is it?

• Achilles tendon pain can affect about 10% of the global population and at least a quarter of running athletes.

  
  

What is wrong? 

• We don’t really know one strong factor that causes Achilles tendon pain. No blood marker, biopsy, or imaging finding predicts pain and then reduces it equally to pain improvements (The Pain of Tendinopathy: Physiological or Pathophysiological?).

• Tendon thickness is due to a water increase in the tendon, potentially an immune response to disperse tendon forces or assist recovery. Don’t worry, as tendon thickness does not relate to the severity of symptoms and does not reduce at the same rate as tendon pain symptoms improve.

• Function loss (reduced strength, running tolerance, or ankle range of motion) in the ankle seems to be related to pain-related movement avoidance rather than tendon change or loss of structure (The majority of patients with Achilles tendinopathy recover fully when treated with exercise alone: a 5-year follow-up + Recreational runners with Achilles tendinopathy have clinically detectable impairments).

• Imaging findings, including the words “partial tears,” “degeneration,” or “intratendinous abnormalities” are part of a tendinopathy diagnosis, but 1) are also all seen in tendons of people without pain 2) “abnormal findings” are less common than “healthy cells” in a painful tendon 3) “abnormal findings” don’t change in appearance equally to pain improvement so can be thought of as age-related incidental findings in a tendon (Treat the donut, not the hole: The pathological Achilles and patellar tendon has sufficient amounts normal tendon structure + Rate of Improvement of Pain and Function in Mid-Portion Achilles Tendinopathy with Loading Protocols + The Tendon Structure Returns to Asymptomatic Values in Nonoperatively Treated Achilles Tendinopathy but Is Not Associated With Symptoms).

• So, we don’t really know what is wrong but have many potentially weak theories about tendon pain. Be skeptical of any strong opinions, and watch out for outdated opinions.

  
  

Why me? 

Most of the time, Achilles pain develops slowly across days, either randomly or after a recent week or month's worth of increased springy activity (Incidence of midportion Achilles tendinopathy in the general population). Periods of life that everyone can go through can reduce your ability to tolerate tendon strain or recover from increased use, such as periods of high mental stress, worsening sleep, or increased weight gain. We know poorer general health, being overweight, or being more sedentary can predispose someone not to tolerate increased Achilles tendon use during standing, walking, running, or jumping if suddenly increased (Explaining Variability in the Prevalence of Achilles Tendon Abnormalities: A Systematic Review With Meta-analysis of Imaging Studies in Asymptomatic Individuals + The impact of loading, unloading, ageing and injury on the human tendon).

(Seth O'Neill - How Does Tendinopathy Develop? (youtube.com)).

What can I do about it? 

• The best management for Achilles tendon pain involves having informed education about the management of tendon pain, modifying exercise dosage if intolerable, and improving general health while adding pain coping strategies to your daily habits. Some people might benefit from adding lower leg exercises to improve tolerance to the activities impacted by Achilles pain (A criteria-based rehabilitation program for chronic mid-portion Achilles tendinopathy).

• Pain during Achilles pain aggravating activities is safe, especially if tolerable. Educate yourself on this condition by asking us for validated, up-to-date information (lots of unhelpful physio fluff is out there). Trialing heel-lifting orthotics or a shoe with a high stack height can be helpful for most people (Efficacy of heel lifts versus calf muscle eccentric exercise for mid-portion Achilles tendinopathy + How To Choose The BEST Running Shoes (Performance | Injury Prevention | Comfort) - YouTube).

• Longer-term options (after 3-6 months of no change in intolerable symptoms) could include seeking shockwave application (we don’t offer this at Method Health at the moment) but keep expectations for improvements relatively low. Manual therapy, including massage or dry needling, offers little evidence of strong effectiveness over exercise only for tendon pain. Other “quick fixes” or “shortcuts” will likely be costly and unhelpful for tendon pain. Surgery is hardly ever suggested for Achilles tendon pain (Adaptation of Tendon Structure and Function in Tendinopathy With Exercise and Its Relationship to Clinical Outcome + "It's disappointing and it's pretty frustrating, because it feels like it's something that will never go away." A qualitative study exploring individuals' beliefs and experiences of Achilles tendinopathy + Talking Tendons: Graded exposure in tendinopathy rehabilitation. on Apple Podcasts).

More tendon pain facts

• For every 1-kg/m2 increase in mean body mass index, an approximately 3% increase in the prevalence of imaging changes was found in this study (Explaining Variability in the Prevalence of Achilles Tendon Abnormalities: A Systematic Review With Meta-analysis of Imaging Studies in Asymptomatic Individuals). Losing weight or maintaining a healthy body weight might be helpful for tendon appearance on imaging.

• Improvement in calf flexibility or strength does not match improvement in tendon pain (Do physical tests have a prognostic value in chronic midportion Achilles tendinopathy? + Can we really say getting stronger makes your tendon feel better? No current evidence of a relationship between change in Achilles tendinopathy pain or disability and changes in Triceps Surae structure or function when completing rehabilitation). Function increases will occur at a different rate from pain improvements.

• “Wait and see” or doing nothing approaches for Achilles tendon pain are not helpful (Which treatment is most effective for patients with Achilles tendinopathy?).

• Fear of movement, called kinesiophobia, low pain self-efficacy (low belief you can complete a task despite pain), and avoiding movement due to concern of increased pain are important psychological beliefs that can reduce the rate of recovery from tendinopathy (Which Psychological and Psychosocial Constructs Are Important to Measure in Future Tendinopathy Clinical Trials? A Modified International Delphi Study With Expert Clinician/Researchers and People With Tendinopathy).

• Pain does not predictably increase with exercises that strain the Achilles tendon more than others. Most people have a variable response to different calf exercises, so experimenting with different exercises is recommended (Achilles tendon forces and pain during common rehabilitation exercises in male runners with Achilles tendinopathy).

• Tendons need really high loads during strength training to change structure. If you care about tendon structure for pain resolution, then you need to place a lot of strain on a tendon. For the calf and hips, think of an external weight close to or greater than your current body weight. For example, a 70kg female might need to progress to being able to complete 70kg single leg calf raises for multiple repetitions to change tendon structure. However, we know that tendon structure does not need to change for tendon pain to improve (Human tendon adaptation in response to mechanical loading  + Effects of Increased Loading on In Vivo Tendon Properties).  

• Isometric muscle contractions do not reduce tendon pain better than other types of muscle contractions as once believed (No Difference in Clinical Effects When Comparing Alfredson Eccentric and Silbernagel Combined Concentric-Eccentric Loading in Achilles Tendinopathy + Talking Tendons: Isometrics in Tendinopathy: they are useful but they are not the cure for cancer on Apple Podcasts + Isometric exercises do not provide immediate pain relief in Achilles tendinopathy).

• If you do not consume 1.2-1.6 grams of protein daily for each body weight kg, collagen protein supplementation might be helpful. However, when protein intake is high enough, collagen does not strongly outperform a placebo (Oral Supplementation of Specific Collagen Peptides Combined with Calf-Strengthening Exercises Enhances Function and Reduces Pain in Achilles Tendinopathy Patients).

• Foot contact position during running does not change the structure of your Achilles tendon (Relationship between Achilles tendon properties and foot strike patterns in long-distance runners). Modifying foot contact during running by increasing step cadence or reducing stride length can be a helpful short-term modification to make running more tolerable for some but does not need to be a long term movement change for runners (Effects of Foot Strike and Step Frequency on Achilles Tendon Stress During Running).

• NSAIDs like Nurofen have little benefit for tendon pain (No Additive Clinical or Physiological Effects of Short-term Anti-inflammatory Treatment to Physical Rehabilitation in the Early Phase of Human Achilles Tendinopathy).

• Neither do most types of injections (Effect of Platelet-Rich Plasma Injection vs Sham Injection on Tendon Dysfunction in Patients With Chronic Midportion Achilles Tendinopathy + Efficacy of high-volume injections with and without corticosteroid compared with sham for Achilles tendinopathy).

  
  

How long will it take? 

• If you are optimistic, have clear expectations and education about what Achilles tendon pain means (more tendon pain does not equal more tendon damage), and follow realistic, up-to-date advice, many can feel much better before or after three months. Many can continue competing at high levels of sport or activity with simple movement modifications and training advice from physiotherapy. Sometimes, it takes more than 12 months to feel better. Don’t be too concerned; just having symptoms for longer does not mean you will not improve when following good advice. Just optimistically keep doing the things that we share that are helpful for your calf health, like improving your general health (sleep, body fat, physical activity, stress coping) (Differences in Recovery of Tendon Health Explained by Midportion Achilles Tendinopathy Subgroups + The effects of pain science education plus exercise on pain and function in chronic Achilles tendinopathy + A 5-year follow-up study of Alfredson's heel-drop exercise program in chronic midportion Achilles tendinopathy). Achilles tendon pain can reoccur even with the best physiotherapy so don’t be too concerned but make a flare up plan of all the helpful things for your tendon (exercise dosage modification, sleep, and mental stress coping) to prioritise more if your tendon pain increases (Recurrence of Achilles tendon injuries in elite male football players is more common after early return to play).

  
  

What can Physiotherapy at Method Health offer? 

• We can offer individual advice to help you modify your active activities to tolerate keeping up with life with Achilles pain. Tendon pain should not stop you from doing the things you love. This might involve adding some strength exercises for your lower legs to your weekly routine or supporting ways to get back to the activities you enjoy and might have reduced or avoided. 

• We can be your support crew to encourage lifestyle changes that can improve your general health, such as coaching you on sleep, guiding you through ways to reduce stress, or adding things to your life to better cope with stress. 

• Suppose you have had persistent tendon pain and are very confused as to why you still have it. In that case, we can help you make sense of the pain, highlight areas of management to prioritise or be more optimistic about, and give you individual guidance to assist in managing and resolving it.