Pronunciation: [sɑːsˈa͡ɪtɪs] (IPA)
Correct spelling for the English word "sarcitis" is [sɑːsˈa͡ɪtɪs], [sɑːsˈaɪtɪs], [s_ɑː_s_ˈaɪ_t_ɪ_s] (IPA phonetic alphabet).
Myositis.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.