Definition:
'Achilles tendonitis' (also 'Achilles tenosynovitis' or 'Achilles tendinopathy') is tendonitis of the Achilles tendon, generally caused by overuse of the affected limb and is more common among athletes training under less than ideal conditions. It should not be confused with xanthoma of the tendon, which is the accumulation of cholesterol in patients with familial hypercholesterolemia.