Patient Portal (231) 935-0550. About; Conditions & Treatments; Our Providers; Patient Resources; Contact ... As the only rheumatology-focused practice within 65 miles of Traverse City, AOC is committed to providing quality healthcare for rheumatology conditions. ... 418 Munson Avenue Traverse City, MI 49686. Phone: (231) 935-0550 Fax: (231) 346 ....