Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP portable upright view of the chest . Lung volumes are low limiting evaluation . The lungs appear relatively clear . There is smooth pleural thickening along the left upper lung as on prior likely related to prior rib injury . No pleural effusion or pneumothorax is seen though the head partially obscures the lung apices . The mediastinal contour and heart appear unchanged . The left humeral head appears medially dislocated as on prior . There is also relative medialization of the right humeral head prosthesis as on prior .
    OUTPUT:
    
No acute findings .