S.E. CHURCHILL 



Fig. 13 Right ulna, M. 54066, 0.5x natural size. 13A, anterior: 13B, 

 lateral; 13C, posterior. 



process on the volar surface. The dorsal and medial surfaces are 

 complete distally to well past midshaft. Only portions of the volar 

 surface of the shaft are preserved. The lateral surface of the shaft is 

 the best preserved, and is almost completely represented from the 



proximal end down to the level of the M. pronator qitadratiis crest 

 distally. 



The trochlear notch opens anteroproximally (the coronoid proc- 

 ess is much higher than the olecranon) (Table 8 and Fig. 14). There 

 is a distinct ridge separating the coronoid and olecranon articular 

 surfaces in the trochlear notch, and there appears to be a small 

 outgrowth of bone just distal of this ridge (on the coronoid articular 

 surface) near the centre of the trochlear notch. There is no indication 

 of degenerative changes to any of the proximal articular surfaces 

 (including the preserved portion of the radial notch). 



The proximal surface of the olecranon process is not very rugose, 

 but vertical striations can be seen on the dorsal margin along the M. 

 triceps brachii insertion. The area of the M. anconeus insertion is 

 weathered and broken, but what is preserved of the muscle scar is 

 non-rugose. The morphology of the proximal M. supinator crest 

 cannot be evaluated because of damage to the medial shaft below the 

 radial notch, but this muscle often extends distally well below the 

 level of the M. brachialis scar and may overlap the proximal end of 

 the interosseus crest. In the case of M. 54066, the distal portion of the 

 muscle attachment can be seen on the proximal shaft, where it is 

 slight but clear, indicating a moderate-to-strong development of the 

 supinator muscle. Only the distal half of the M. brachialis scar is 

 preserved, which appears as a well defined, raised scar with clear 

 borders. There is a thin yet clear crest for M. pronator teres, but no 

 clear origin area for the ulnar head of M . flexor digitorum superficialis 

 can be seen. 



More distally, the interosseus crest is a clear, sharp line that 

 diminishes around midshaft and then picks up again on the distal- 

 most part of the fragment as a broader, rugose line. There is a 

 pronounced medial deviation of the shaft at the level of the M. 

 brachialis scar, but this may be a function of post-mortem damage 

 and reconstruction of the shaft from numerous fragments. The 

 cortical bone thickness in the proximal shaft (at the level of the 

 beginning of the interosseus crest) is 2.0mm, while in the distal shaft 

 (at the level of the M. pronator quadratus crest) it is 2.3mm thick. 



M.54067 (GC 87 226 A) (Fig. 15) 



Left 



This is a proximal left ulna, with a total length of 58.1mm. This may 



represent the antimere of the right side ulna M. 54066 (see above), 



and may come from the same bone as M. 54068 (see below). Only the 



Table 8 Ulnar dimensions (mm) 



M.54066 



M.54067 



M.54069 



Olecranon length (M-8) 



Olecranon height (M-7) 



Olecranon breadth (M-6) 



Trochlear notch chord (M-7( 1 )) 



Coronoid height" 



Radial facet maximum diameter'' 



Radial facet minimum diameter*' 



Diaphyseal sagittal trochlear angle (M-15a) 



Proximal anteroposterior diameter^ 



Proximal transverse diameter' 



Proximal circumference' 



Crest anteroposterior diameter ( M- 1 1 ) 



Crest mediolateral diameter (M-12) 



Midshaft anteroposterior diameter* 



Midshaft mediolateral diameter* 



Midshaft circumference'' 



20.8 

 24.4 

 26.3 

 23.7 

 37.1 

 015) 

 [9.5] 

 15° 

 18.1 

 18.9 



18.9 



21.6 

 (17.4) 

 (17.5) 

 (53) 



(25) 

 25.2 



18.1 



21.9 



14.7 

 11.3 

 45 



■' maximum anteroposterior diameter from the dorsal surface of the bone to the anterior tip of the coronoid process (McHenry et al.. 1976). 



'' maximum and minimum diameters of the articular facet for the radial head. 



' taken at the level of the distal border of the ulnar tuberosity (McHenry et al.. 1976). 



'* midshaft location estimated. 



