Question: My podiatrist recently treated a patient for peroneal tendinitis. What is peroneal tendinitis, and which ICD-10-CM codes should I look to for reporting this condition? Wisconsin Subscriber Answer: Peroneal tendinitis is a condition where the peroneal tendons, which are situated side-by-side along the exterior ankle bone, become inflamed. This inflammation is typically a result of excessive strain and overuse of these tendons, which causes them to chafe against the bone. This rubbing then triggers swelling in the tendons. As a response to the added strain, the tendons gradually enlarge in an attempt to handle the increased load more effectively. Common signs and symptoms of peroneal tendinitis include: You should look to the following ICD-10-CM codes when reporting peroneal tendinitis: Lindsey Bush, BA, MA, CPC, Development Editor, AAPC