

The Thorax. 121 



that runs along the lower border of the rib above. The 

 wound is generally made in the axillary region, either in 

 the eighth or ninth intercostal space, close in front of the 

 scapular line, or higher up through the sixth or seventh 

 intercostal space in the midaxillary line, and the struc- 

 tures divided are : The integument, superficial and deep fas- 

 ciae, serratus magnus muscle, external intercostal fascia, 

 external intercostal muscle, middle intercostal fascia, in- 

 ternal intercostal muscle, internal intercostal fascia, sub- 

 pleural tissue and the pleura. An incision made elsewhere 

 would necessarily be much deeper than in this region, 

 since the pectoralis major in front, and the latiss. dorsi 

 and dorsi muscles behind, would add to the depth of 

 the wound, while an operation in the anterior portion of 

 the intercostal spaces might divide the internal mammary 

 artery near the sternum, or the trunk of the intercostal ar- 

 tery, where it crosses the parallelogram, referred to on 

 page 117, if the incision be made in the posterior region. 



Bisection of a rib is employed when the space between 

 the adjoining ribs is not sufficient for proper drainage, 

 and is done through an incision similar to that of thora- 

 cotomy, with the exception that, instead of dividing the in- 

 tercostal muscles to expose the pleura, this membrane, in 

 exsection, is opened after stripping back the periosteum 

 and dividing the rib. If the rib were sawn through be- 

 fore separating the periosteum from it, the intercostal ar- 

 tery would be wounded at an inopportune time, i.e., before 

 it could be readily ligated, whereas, when the periosteum 

 is pushed back, it carries the vessel with it, so that, it may 

 be divided and ligated after the rib has been removed. 

 Estlanders operation consists in the removal of the parts 

 of a number of ribs, to allow the chest wall to fall in, on a 

 lung that has been compressed by the pressure of a long- 

 standing empyema, and is performed in a manner similar 

 to exsection. 



