Hello. can you please tell me whether there are any visible signs of advanced age in a skeletal ulna?

Depends on age : There is a growth plate at the end of the ulna near the wrist. Time of fusion can approximate bone age of patient. Usually when completely fused about 16 years of age with variability between men and women. Females are usually approximately two years more advanced than males. Fusion of growth plates particularly legs can sometimes predict ultimate growth of the individual.