Background: Pulmonary torsion is a rare complication following thoracic surgery.
Case presentation: A man in his seventies was diagnosed with stage IIIA lung cancer occupying the right upper lobe, and lobectomy was performed through posterolateral thoracotomy. Postoperative chest X-rays revealed extensive, progressive middle lobe opacities on postoperative day 0 and 1, with no corresponding clinical or bronchoscopic findings. Contrast-enhanced computed tomography raised suspicion of middle lobe torsion, and exploratory surgery confirmed the finding of a necrotic middle lobe with 180 degrees of torsion. The middle lobe was resected and the patient recovered well.
Interpretation: Pulmonary lobar torsion is a rare but potentially life-threatening complication following thoracic surgery that should not be overlooked even in the absence of symptoms that raise concern. Bronchoscopy and radiological imaging may suggest the condition, but the final diagnosis is made surgically.