Achilles tendinopathy is commonly divided into insertional disease at the calcaneal attachment and midportion disease several centimeters above it. The distinction matters because insertional tendon is exposed to additional compression against the heel bone during dorsiflexion, while midportion tendinopathy is predominantly managed around tensile load capacity. The two presentations can require different exercise modifications and should not automatically receive the same shockwave or rehabilitation protocol.
Where is the pain?
| Insertional | Midportion | |
|---|---|---|
| Location | At or very near the attachment on the back of the heel bone | Typically about 2–6 cm above the insertion |
| Load on the tendon | Tensile load plus compression against the calcaneus | Mainly tensile load |
| Often aggravated by | Uphill walking, stairs, deep dorsiflexion, heel drops off a step, shoe heel-counter pressure | Running, hopping, jumping and spikes in training load |
| Common nearby findings | Retrocalcaneal bursitis, a prominent posterior heel (Haglund morphology) | Thickening of the tendon body |
These are typical patterns, not rules. Some people have symptoms in both regions, and the exact site of tenderness matters more than the label someone has been given.
What both have in common
Both are tendinopathies: persistent tendon pain with reduced tolerance to load, rather than a short-lived inflammation. That is why "Achilles tendonitis" is an older and less accurate term for most chronic cases. Typical shared features include stiffness first thing in the morning or after rest, pain that eases a little once warmed up and then returns later, and reduced calf endurance. Both respond to progressive loading over time, and both can take months to settle.
How the examination tells them apart
- Where it is tender: pressing along the tendon usually localizes the sore area to the attachment or to the narrower section a few centimeters higher.
- What provokes it: insertional pain is often worse when the ankle is pushed into dorsiflexion, such as standing with the heel dropped off a step. Midportion pain tends to track how much running, hopping or calf work the tendon has been asked to do.
- How the tendon handles load: single-leg heel raises, repeated calf raises and, when appropriate, hopping show current capacity and help set a starting point for rehabilitation.
- What else is present: swelling at the back of the heel, a prominent heel bone, weakness or a gap in the tendon point toward other findings that change the plan.
No single test settles it, so the examination combines several findings.
Why compression matters at the insertion
As the ankle bends upward (dorsiflexion), the Achilles tendon wraps around the back of the heel bone just above its attachment. That brings compression into the picture on top of the normal pulling, or tensile, load. In insertional disease, positions that combine both, such as letting the heel drop below the level of a step, may be the most provocative.
The insertional tendon is exposed to both tensile load and compression against the calcaneus as the ankle moves into dorsiflexion. That is one reason rehabilitation for insertional disease is often modified to avoid excessive dorsiflexion early in treatment. Range is usually reintroduced as tolerance improves; insertional tendons are not meant to avoid dorsiflexion permanently.
How midportion tendinopathy behaves
The midportion is the narrowest part of the tendon, a few centimeters above the heel. Compression against bone is not a major factor there. Symptoms usually track how much load the tendon is asked to handle relative to its current capacity, such as a jump in running mileage, more hill work or a return to sport after a break. Rehabilitation focuses on gradually building that capacity.
How the location changes loading
Modern Achilles rehabilitation is broader than eccentric heel drops. Depending on stage and irritability, it may include isometric holds, slow heavy calf raises, eccentric-concentric work, energy-storage exercises such as hopping, and sport-specific progression.
- Insertional: loading often starts on flat ground rather than off a step, limiting deep dorsiflexion early, with range added back as symptoms allow. Footwear with a little heel height, or avoiding pressure from a stiff heel counter, may reduce compression in irritable phases.
- Midportion: full-range loading, including heel drops below step level, is usually better tolerated, with progression guided by symptoms during and after loading.
Traditional heel-drop programs performed below the level of a step may be poorly tolerated in insertional disease because they increase compression at the tendon insertion. That does not make eccentric loading wrong for insertional tendons. It means the program usually needs adapting.
Does the location change how shockwave results apply?
Yes. The research has generally studied one group or the other:
- Insertional: in a 2008 randomized trial of 50 patients with chronic recalcitrant insertional tendinopathy, low-energy shockwave outperformed a traditional eccentric loading program at four months. VISA-A rose from 53 to 80 versus 53 to 63, pain fell from 7 to 3 versus 7 to 5, and 64% versus 28% reported being completely recovered or much improved.
- Midportion: in a 2007 randomized trial, shockwave and eccentric loading were both better than wait and see, with similar results, and in 2009 adding shockwave to loading improved four-month outcomes in a refractory group.
A result from one region should not be assumed to apply to the other. The full picture is in shockwave therapy for Achilles tendinopathy.
What else can cause pain at the back of the heel?
- Partial tear: a sudden onset during forceful loading, marked weakness or a palpable defect.
- Achilles rupture: a sudden pop or snap, a feeling of being kicked in the back of the leg, and difficulty pushing off. This needs urgent medical assessment.
- Retrocalcaneal bursitis: irritation of the bursa between the tendon and the heel bone, which often accompanies insertional tendinopathy.
- Haglund morphology: a prominent upper back corner of the heel bone that can add to compression. Many people have it without pain, so it is not automatically the cause.
- Plantar heel pain: pain under the heel rather than behind it, usually worst with the first steps in the morning. See plantar fasciitis and heel pain.
- Nerve-related or referred pain: burning, numbness or tingling suggests a different source.
When is imaging useful?
Most Achilles tendinopathy is diagnosed clinically from the location of pain, how it behaves and how the tendon responds to load. Ultrasound or MRI can help when a partial tear is suspected, after a sudden injury, with marked weakness or atypical symptoms, when appropriate care has not helped over time, or before surgery. A thickened tendon or increased blood flow on ultrasound does not by itself show what is causing pain or how severe the problem is.
How Novo evaluates Achilles pain
We examine first: exactly where the tendon hurts, morning stiffness, walking and running tolerance, calf raise capacity, ankle dorsiflexion, sensitivity to compression at the insertion, signs of a tear, and what has already been tried. The aim is to identify whether the problem is insertional, midportion or something else before deciding on loading, shockwave, imaging or referral. See how we approach Achilles tendinopathy, or book a new patient exam.
References
- Rompe JD, Furia J, Maffulli N. Eccentric loading compared with shock wave treatment for chronic insertional Achilles tendinopathy: a randomized, controlled trial. Journal of Bone and Joint Surgery (American). 2008;90(1):52-61. PMID 18171957. (link)
- Rompe JD, Nafe B, Furia JP, Maffulli N. Eccentric loading, shock-wave treatment, or a wait-and-see policy for tendinopathy of the main body of tendo Achillis: a randomized controlled trial. American Journal of Sports Medicine. 2007;35(3):374-383. PMID 17244902. (link)
- Rompe JD, Furia J, Maffulli N. Eccentric loading versus eccentric loading plus shock-wave treatment for midportion Achilles tendinopathy: a randomized controlled trial. American Journal of Sports Medicine. 2009;37(3):463-470. PMID 19088057. (link)
