How Diabetes Can Lead to Tendon Damage

Medically Reviewed by Michael Dansinger, MD on May 21, 2023
3 min read

If you have diabetes and you hurt when you move, it might be due to problems with your tendons. They're cord-like bands that connect your muscles to your bones. The high blood sugar levels that may go along with your disease play a role in stirring up your tendon trouble.

You have tendons all over your body, including in your shoulders, arms, wrists, hips, knees, and ankles. They transfer the force from your muscles to your bones so you can move.

If your diabetes isn't under control, your tendons can thicken and become more likely to tear.

Tendon damage in type 1 and type 2 diabetes happens because of substances called advanced glycation end products (AGEs). They form when protein or fat mixes with sugar in your bloodstream.

Normally, your body makes AGEs at a slow and steady pace. But when you have diabetes, the extra sugar in your blood cranks up the speed, which affects your tendons.

Tendons are made from a protein called collagen. AGEs form a bond with it that can change the tendons' structure and affect how well they work. For instance, they could get thicker than normal and might not be able to hold as much weight as they used to. As a result, your odds of getting a tear in one of your tendons go up.

Some tendon problems you could get if you don't get your diabetes under control are:

  • Frozen shoulder: Stiffness and pain that happens when a capsule that surrounds tendons and ligaments in your joint thickens up.
  • Rotator cuff tears: Damage to the tendons and muscles that surround your shoulder joint, including the supraspinatus muscle.
  • Trigger finger: Your finger becomes stuck in a bent position and straightens with a snap, like the sound of a trigger being pulled.
  • Carpal tunnel syndrome: You get numbness, tingling, and weakness in your wrist because of pressure on the nerve that runs through it.
  • Dupuytren's contracture: Thickening of the tissue under the skin of your hand that causes your fingers to bend in toward your palm.

Tendon damage is painful and can hinder how much you can move your joint. Even if you have surgery to fix the damage, the tendon can tear again. Studies show that more than a third of people with diabetes who have surgery to fix a torn rotator cuff will get the problem again.

Exercise is important to help keep your diabetes under control, but you may find it harder to work out when your tendons are painful and stiff.

Damage to the Achilles tendon in the back of your heel can put a cap on how much you can move your ankle. This limited motion forces you to put extra pressure on the middle of your foot with each step, which increases your risk for foot sores.

Talk to your doctor about ways to make sure your blood sugar levels stay down while you recover from tendon problems.

The best way to avoid tendon problems is to get your diabetes under control. Lower your blood sugar with the help of diet, exercise, and medicine. And if you're overweight, try to shed some pounds. It will improve your health and take pressure off your tendons at the same time.

If you already have tendon damage, ask your doctor about treatments like these:

Your doctor may also suggest a steroid shot into your joint to relieve tendon problems. Keep in mind that steroids can cause a short-term spike in your blood sugar levels. Ask your doctor whether the benefits of this treatment outweigh the risks.