Achilles Tendon Tendinopathies
Do you have Achilles tendon tendinopathy? What exactly are we talking about?
The Achilles tendon is the largest and strongest tendon in the body. It is surrounded by the paratenon, a fibrous layer that is vascularized and innervated. Calcaneal tendinopathies account for 30 to 50% of sports-related injuries. Recovery is often difficult because this region has poor blood supply.
The tendon is composed of 75 to 90% collagen fibers (type I collagen) and only 2% elastin. What gives this tendon its elasticity is the twisted organization of the tendon fibers. This structure allows it to store elastic energy and release it during propulsion.
Different types of conditions may be found depending on the location, and the physiotherapy treatment will differ accordingly:
- Retrocalcaneal bursitis: inflammation of the bursa (a “small sac” of fatty tissue between the Achilles tendon and the calcaneus), an inflammatory condition that responds to anti-inflammatory treatment.
- Calcaneal tendon tendinosis.
- Achilles tendon tendinosis.
- Calcaneal enthesopathy.
- Paratenonitis: inflammation of the paratenon, the fibrous sheath surrounding the Achilles tendon.
- Myotendinous tendinopathy.
Enthesopathy
Enthesopathy is an involvement of the Achilles tendon enthesis at its insertion on the calcaneus. The pain develops progressively and is particularly sensitive to resisted muscle contraction. It is present during activity and on palpation, with frequent morning stiffness. The tendon appears thickened, with local inflammatory signs (swelling, redness, warmth).
Tendinosis
This is not an inflammation; it is a reorganization of the tendon fibers due to lack of recovery and/or overuse.
It is a degenerative lesion located away from the insertion, between 2 and 6 cm above the calcaneus. The pain develops progressively and is aggravated by stretching of the tendon and resisted contraction of the triceps surae. It appears during activity and on palpation, often associated with morning stiffness. The tendon is thickened, sometimes with a palpable nodule that moves with dorsiflexion, without clear inflammatory signs.
Myotendinous Junction Tendinopathy
(Myotendinous junction syndrome)
This is an involvement of the transition zone between the triceps surae muscle and its tendon. Pain is progressive and triggered or aggravated by stretching and muscle contraction. It is present on palpation and during activity, with localized swelling that can be detected on clinical examination or imaging.
Paratenonitis
Paratenonitis is an inflammation of the paratenon, the fibrous tissue surrounding the Achilles tendon. Pain appears progressively and is sensitive to stretching. It occurs during activity, on palpation, and when the tendon is pinched between the fingers. Morning stiffness is prolonged. In some cases there is crepitus on palpation, tendon thickening, and sometimes a nodule that remains immobile during dorsiflexion, with associated inflammatory signs.
Differential Diagnosis
The main differential diagnoses to consider are: retro- or pre-calcaneal bursitis, posterior calcaneal spur (Haglund’s syndrome), Sever’s disease in children, inflammatory rheumatic disease, and partial or complete rupture of the Achilles tendon.
Focus on Tendinosis
Mechanisms of Achilles Tendon Tendinosis
The tendon is a structure that continuously remodels, particularly during physical activity. The balance between breakdown and regeneration (remodeling) must be respected. If physical activity is too intense (duration, intensity, mechanical load, with little or no recovery time), the tendon can no longer regenerate properly. Scar tissue then forms, with fibers that reorganize in a more longitudinal pattern. The tendon loses its elastic properties.
When this pattern persists, the body produces more fibers to protect the tendon, which is why palpation reveals a thickened tendon. At the lesion site, ultrasound may show a small nodule, which is actually the result of the same protective mechanism.
For Sport medicine journal you can read more here.
Clinical Features of Tendinosis
- Pain on palpation 2 to 6 cm above the calcaneus.
- Gradual onset of pain.
- Pain with stretching and resisted contraction.
- Pain during sports activity.
- Morning stiffness.
- Thickening of the tendon, sometimes with a palpable nodule.
- No inflammatory signs.
When the condition is well established or in an acute phase, patients often report: Morning stiffness, Pain when walking, going up or down stairs.
Preferred Medical Imaging Examination: Ultrasound
The calcaneal tendon appears fusiform, transversely thickened, with hyperemia on Doppler and sometimes a nodule.
Triggering Factors
- Excessive sports activity.
- Footwear problems (shoes not adapted to the surface, worn-out cushioning, collapsed shock absorption, etc.).
- Dehydration.
- Previous ankle sprain.
- Orthopedic dysfunctions of the foot, but also the knee, hip, sacrum, ilium, etc.
- Medication use. If Achilles tendon pain is related to medication side effects, the physiotherapy approach described here is not appropriate; it is better to reassess with the prescribing physician.
Patient Involvement
Recovery from Achilles tendon tendinopathy (AT) is a team effort. It is essential that the following recommendations are followed alongside physiotherapy treatment to enable fast and effective recovery.
Your physiotherapist will give you a specific protocol of exercises, icing, and massage to perform daily.
Diet and hydration are also crucial: dehydration and/or an acidifying diet promote Achilles tendinosis.
Physiotherapy Treatments
- Osteopathic assessment and manipulation/mobilization of the foot, as well as the knee, hip, pelvis, and the contralateral lower limb.
- Visceral therapy: support for kidney function. The kidneys, together with the lungs, regulate the body’s acidity. If acidosis sets in, pain appears (joint pain, tendinopathies, fatigue, spasms, contractures, etc.).
- Muscle assessment: stretching mainly of the psoas muscle and calf muscles.
- Massage of the Achilles tendon and calf.
- Stanish protocol.
- Others: instrument-assisted soft tissue mobilization, taping, shockwave therapy with a muscular head.
Treatment of Paratenonitis, Enthesopathy, and Myotendinous Junction Syndrome
Paratenonitis
- Rest until acute pain disappears.
- Icing.
- Gentle calf stretching to maintain tendon flexibility, 1 to 2 times a day for 45 minutes.
- Ankle mobilization and joint pumping.
- Anti-inflammatory medication prescribed by the physician.
Enthesopathy
- Shockwave therapy as first-line treatment, using a gold head.
- Massage of the enthesis, tendon, and calf.
- Calf stretching 1 to 2 times a day for 45 seconds.
- Instrument-assisted techniques, daily icing, taping.
- Gentle Stanish protocol, only twice a week.
Myotendinous Tendinopathy
This condition is often ignored by patients but can lead to tendinosis if it persists. Treatment is broadly similar to that of tendinosis, with the addition of proprioceptive work combined with eccentric muscle strengthening.
Associated Medical or Paramedical Treatments
- Recommend a dental check-up.
- Orthotic insoles prescribed by a podiatrist.
- No anti-inflammatory medication during shockwave therapy.
- PRP (platelet-rich plasma) injections, to be considered by a rehabilitation physician after the second phase of shockwave therapy if pain persists.
- Tecar therapy.
- Electrotherapy.
Clinical improvement should be noticeable after 4 to 5 weeks of physiotherapy, at a frequency of 2 to 3 sessions per week.
Stop Ignoring Achilles Pain
The longer tendinopathy is left untreated, the harder it is to heal. Start evidence-based physiotherapy now and protect your tendon long-term.
