Thought this might be of interest as the deer was browsing normally pre-shot and was subsequently found to be in reasonable condition.
The bony lump to the jaw was first evident on general external examination prior to gralloch. Its size and exact impact only became evident on further examination and skinning of the head. The interesting link with the sternum abnormality was only explained following veterinary advice.
This is a condition often referred to as 'lumpy jaw" and is an infectious agent introduced from the soil via a cut or abrasion in the mouth/gum area. This can arise from sharp browse or plant material or through sandy/gravel soil being chewed amongst browse. The infection attacks the bone in the jaw and can displace the teeth eventually leading to difficulty in chewing, feeding and eventual deterioration and death from starvation.
In an otherwise normal and apparently healthy animal it might not be a reason to cull as it would not necessarily be visible and the animal would cope normally until the growth became too large. The sternum abnormality is a direct result of the blood borne nature of the infection which has taken root in another area of bone in the skeleton, in this case the sternum, and has produced distinctive pus filled cavities which are framed with bone like overgrowth.
Most importantly, the nature of the infectious agent (i.e. blood borne) meant that the carcass was condemned. Interested to know if anyone else has encountered this and have an article to a specific study on the condition in European Roe if anyone is interested.