BACKGROUND Differentiating traumatic tricuspid regurgitation (TR) from infective endocarditis (IE) is clinically crucial in patients presenting with abnormal tricuspid valve findings after blunt chest trauma. Particularly, papillary muscle rupture caused by trauma can produce mobile valvular structures that closely resemble vegetations, making accurate diagnosis challenging in the acute setting. CASE REPORT A man in his 60s with pulmonary sarcoidosis was admitted after a 5-m fall, sustaining multiple fractures. Preoperative transthoracic echocardiography revealed a 7-mm mobile structure on the anterior tricuspid leaflet with flail motion and severe TR. Because of fever, IE was suspected; however, blood cultures and further investigations excluded IE. A diagnosis of traumatic TR due to papillary muscle rupture was made. Although the patient was hemodynamically stable under medical therapy, the heart team recommended surgery to prevent long-term heart failure. Four months after fracture repair, tricuspid valve repair with artificial chordae and annuloplasty was performed. The surgical findings were fully consistent with the preoperative diagnosis, and pathological examination of the ruptured papillary muscle demonstrated coagulative necrosis without significant inflammatory infiltration, supporting a traumatic etiology. At 4-year follow-up, he remains stable without signs of heart failure exacerbation. CONCLUSIONS Accurate differentiation between traumatic TR due to papillary muscle rupture and IE is essential, as misclassification may lead to unnecessary antimicrobial therapy or delayed surgical intervention. This case highlights how mobile traumatic lesions can closely mimic vegetations and underscores the importance of comprehensive evaluation to guide appropriate management and optimize outcomes.