Radiographic evaluation of appendicular skeletal maturation in the common marmoset (Callithrix jacchus)

Abstract

The times of appearance and fusion of 75 ossification centers were recorded by age. The appendicular skeletal development of 6 common marmosets was monitored radiographically at weekly intervals from 1 day to 94 weeks of age. Data were recorded for each monkey on a weekly basis and finally data on all animals were recorded on separate tables of thoracic and pelvic limb ossification centers. From these tables a range and average age for appearance and fusion of each ossification center were calculated. Standard deviations, derived from these observations, indicated that the most consistently appearing centers of ossification (standard deviation - 0.2) were the distal epiphysis of the radius (average age - 0.8 weeks), the distal epiphyses of the metacarpal bones (average age - 1.8 weeks), and the distal epiphyses of the metatarsal bones (average age - 3.8 weeks). Other ossification centers which were slightly less consistent in appearance (standard deviation - 0.3) were the intermediate carpal bone (average age - 3.4 weeks), tarsal bone IV (average age - 3.6 weeks), the proximal epiphysis of the radius (average age - 8.4 weeks), and the proximal epiphysis of the ulna (average age - 8.6 weeks). Those epiphyses which are most consistent in their times of fusion were the proximal epiphysis of the humerus (average age - 93 weeks, standard deviation - 0.5), the proximal epiphysis of the fibula (average age - 83.5 weeks, standard deviation - 3.1), the distal epiphysis of the humerus (average age - 17.2 weeks, standard deviation 4.7), and the proximal epiphysis of the femur (average age - 62.6 weeks, standard deviation - 5.3).