S.E. CHURCHILL 



CLAVICULAR REMAINS 



M.54053(M23.1/l)(Fig. 1) 

 Left 



This is a complete clavicle. With the exception of some abrasion and 

 erosion of the sternal end on the inferior margin and to a portion of 

 the superior edge, and some very slight damage to the lateral edge of 

 the acromial articular surface, the bone is in a perfect state of 

 preservation. There is marked curvature to both the medial and 

 lateral ends of the shaft. There is very little torsion to the shaft, except 

 at the very proximal end, such that the long axis of the sternal 

 articulation is oriented at 135° to the horizontal plane of the acromial 

 end. Medially the shaft cross-section forms an isosceles triangle with 

 the base superior, while laterally the shaft is more rectangular in 

 section, with the superoinferior dimension being the smaller. 



Fig. 1 Left clavicle, M.54()53, natural size. lA, superior; IB, inferior. 



Fig. 2 Right proximal clavicle, M.54054, natural size. 2A, superior; 2B, 

 inferior. 



Cutmarks are evident on the medial inferior surface (around the 

 costoclavicular ligament attachment area), near midshaft, and on the 

 anterosuperior margin of the acromial facet (see Andrews & 

 Femandez-Jalvo, this series of papers). 



Along the superior surface, there is very mild rugosity at the 

 insertion area for M. Sternocleidomastoideus. There is a weak but 

 clear crest delimiting the superior edge of the M. pectoralis major 

 origin on the superoventral margin of the medial third of the shaft. 

 Just lateral of midshaft this crest blends with the origination scar for 

 M. deltoideus. Medially the M. deltoideus scar is rugose and well 

 defined, laterally the muscle origin is marked by a clear crest 

 superiorly and a rugose tubercle laterally, but the bone surface over 

 most of this part of the origin area is not especially rugose. The 

 insertion area for M. trapezius is marked by some smooth tubercles 

 medially (just medial of the level of the conoid tubercle) and some 

 rugosity just mediodorsal of the acromial articular surface. The 

 superior surface of the acromial end is relatively smooth. 



On the inferior surface, the origin of M sternohyoid can be seen as 

 a small patch of very slight rugosity. The costoclavicular ligament 

 attachment is marked by a pit with small exostotic projections lining 

 the dorsal edge of the ligament scar. The oval costoclavicular liga- 

 ment scar is continued laterally as a rugose broad ridge extending 

 roughly 29mm along the inferior shaft. This ridge may mark the 

 inferior edge of M pectoralis major, perhaps including some of the 

 attachment area of M. subclaviiis and the clavipectoral fascia near 

 midshaft. The conoid tubercle is well defined and large, and projects 



