Nongonococcal septic arthritis in adults is usually caused by infections with staphylococcal or streptococcal species. In patients with underlying diseases, especially those with chronic joint disease or malignancy, bacterial isolates from infected joint spaces may include group G streptococci. Occasionally, group G streptococcal arthritis may occur in otherwise healthy individuals. We report a case of pyogenic sacroiliitis in a healthy young adult and review the pertinent literature concerning group G streptococcal arthritis.