Achilles tendinitis

The Achilles tendon is the thick band at the back of the ankle that anchors the calf muscles to the heel bone. Achilles tendinitis (also called tendinopathy) is pain and wear in this tendon, usually from repeated strain rather than a single injury. It can affect the middle of the tendon or the spot where it attaches to the heel.

• Pain and stiffness along the back of the ankle or heel, often worst in the morning
• Pain that increases with activity, or is noticeably worse the day after exercise
• Thickening or swelling of the tendon
• Tenderness when the tendon is squeezed
• Pain where the back of a shoe presses on the heel
• Difficulty rising onto the toes

Achilles tendinitis usually comes from doing too much, too soon — repeated stress that the tendon has not had time to adapt to. It takes two main forms:

• Non-insertional tendinitis affects the middle part of the tendon and is more common in younger, active people, especially runners.
• Insertional tendinitis is centered at the very bottom of the tendon, at its attachment on the heel. Bone spurs often form there, and it is seen in active and inactive people alike.

Risk factors include:

• Ramping up mileage, speed, or training load too quickly
• Tight calf muscles
• Running on hard surfaces or hills, or frequent jumping
• A change in footwear, or shoes with poor support
• A bony bump on the back of the heel (Haglund's deformity)
• Flat feet or arthritis, particularly in middle-aged and older adults

A clinician examines the tendon for swelling, thickening, and tenderness, and checks calf flexibility and ankle motion. X-rays can show bone spurs or calcium deposits near the heel. Ultrasound or MRI is not usually needed to make the diagnosis but may be used to look for a tear or when surgery is being considered.

Most people improve without surgery, though it often takes patience. Common non-surgical measures include:

• Cutting back on activities that cause pain and switching to low-impact exercise, such as cycling or swimming
• Ice for short periods after activity
• Calf stretching and a structured strengthening program, often including eccentric exercises (slowly lowering the heel), usually guided by a physical therapist
• Heel lifts or supportive shoes; for insertional tendinitis, shoes with a soft or open back
• A walking boot for a short period when pain is severe
• Anti-inflammatory medication for a limited time when appropriate
• Shockwave therapy for some people whose symptoms persist

Steroid injections into the Achilles tendon are generally avoided because they can weaken the tendon and raise the risk of rupture.

Surgery may be considered when significant pain continues after about six months of consistent non-surgical care. Depending on the problem, it can involve removing damaged tendon tissue and any bone spur, repairing the tendon, transferring a nearby tendon for added strength, or lengthening a tight calf muscle.

Non-surgical recovery commonly takes a few months, and symptoms can return if the tendon is overloaded again before it is strong. A gradual, planned return to running and jumping helps.

Recovery after surgery is longer. It involves a period in a boot or cast followed by an extended rehabilitation program; your surgeon will outline the plan.

• Increase training distance and intensity gradually
• Stretch and strengthen the calf muscles regularly, without forcing painful stretches
• Warm up before exercise, and mix in low-impact activities
• Wear supportive athletic shoes and replace them when worn