Projection of the triangle of auscultation on the human pulmonary surface

The projection of the triangle of auscultation on the posterior aspect of the pleuropulmonary surface was studied in 36 embalmed cadavers (19 males and 17 females). A total of 58 observations was made in 22 cadavers bilaterally and in 14 unilaterally, after introducing a long pin at each angle of the dissected triangle of auscultation deep into the pulmonary parenchyma. The projection of the triangle of auscultation, limited by the m. latissimus dorsi, m. trapezius and the medial margin of the scapula, was always found on the inferior lobe of the corresponding lung in one or more segments. It was found on the superior segment of the inferior lobe (43.1% isolatedly; 67.2% with other segments), the posterior basal segment (13.8% isolatedly; 43.1% with other segments) and on the lateral basal segment (10.3% isolatedly; 39.7% with other segments). Identical bilateral projections occurred in 50% of the cases.