Achilles Tendinopathy & Rupture

The Achilles tendon is the largest and strongest tendon in the body, connecting the calf muscles to the heel bone and playing a central role in walking, running, and jumping. It is also prone to two quite different problems — tendinopathy, a gradual, overuse-related degeneration, and rupture, a sudden and complete tear — that share the same anatomy but require very different management.

Tendinopathy vs rupture

Achilles tendinopathy develops gradually, through repetitive overload of the tendon that outpaces its capacity to repair itself, producing a degenerative change in the tendon’s structure rather than a discrete injury. Achilles rupture, by contrast, is a sudden, complete tear of the tendon, typically occurring during a forceful push-off movement such as sprinting or jumping, often in patients with no significant prior symptoms — though pre-existing, undiagnosed tendinopathy is thought to weaken the tendon and contribute to rupture risk in some cases. The two conditions are managed quite differently, which makes an accurate initial diagnosis important.

Causes and risk factors

Tendinopathy typically develops from a mismatch between load and the tendon’s capacity to adapt — a sudden increase in running volume or intensity is a classic trigger, as is a change in training surface or footwear. Rupture risk is increased by a sudden, forceful push-off movement, particularly in middle-aged recreational athletes returning to high-intensity sport after a period of relative inactivity, a group in which Achilles rupture is disproportionately common.

Symptoms of each

• Tendinopathy — gradual onset of pain and stiffness in the tendon, typically worse with activity and often most noticeable first thing in the morning
• Tendinopathy — tenderness and sometimes a palpable thickening along the tendon
• Rupture — a sudden, sharp pain often described as feeling like being kicked or struck in the back of the ankle
• Rupture — an audible pop at the time of injury, followed by significant weakness pushing off through the foot
• Rupture — a palpable gap in the tendon in some cases, though swelling can make this difficult to detect

How each is diagnosed

Tendinopathy is diagnosed clinically, based on the pattern and location of pain, supported by ultrasound imaging where the diagnosis or extent of tendon change is unclear. A suspected rupture is assessed with a specific clinical test — the calf squeeze (Thompson) test, in which the absence of normal foot movement on squeezing the calf strongly suggests a complete tear — with ultrasound or MRI used to confirm the diagnosis and characterise the tear where needed.

Non-surgical management

• Eccentric loading exercises — a specific, structured strengthening programme that is the evidence-based cornerstone of tendinopathy management
• Activity modification — reducing the high-impact loading that is driving symptoms
• Heel lifts or footwear modification — reduces tension through the tendon during the acute, most symptomatic phase
• Anti-inflammatory medication — for symptomatic flares, used cautiously and not as a substitute for a loading programme

When surgery is considered

For tendinopathy, surgery is considered only after a genuine, structured trial of eccentric loading and other non-surgical measures has failed to resolve persistent symptoms. For a complete rupture, the decision between surgical repair and non-surgical management (structured bracing and rehabilitation) depends on individual factors including activity level and the specific pattern of the tear, and is discussed individually — both approaches are supported by good evidence in appropriately selected patients.

Frequently asked questions

What’s the difference between Achilles tendinopathy and a rupture?

Tendinopathy is a gradual, overuse-related degeneration of the tendon causing pain and stiffness over time. A rupture is a sudden, complete tear, typically causing sharp pain and an audible pop during forceful activity. The two require different assessment and treatment.

Does a ruptured Achilles tendon always need surgery?

No. Both surgical repair and non-surgical management with structured bracing and rehabilitation are supported by good evidence in appropriately selected patients. The right choice depends on individual factors, discussed at consultation.