Forensic age estimation in living individuals using 3.0T MRI of the distal femur

Abstract

To increase the reliability of forensic age estimations in living adolescents and young adults where there is no legitimation for X-ray examinations, it would be desirable to establish radiation-free imaging methods. In the present study, the ossification stage of the distal femoral epiphysis was determined retrospectively in 166 male and 124 female individuals in the age group 10 to 30 years using 3.0T MRI. When evaluating the ossification stage, a combination of the classifications proposed by Schmeling et al. and by Kellinghaus et al. was used. Within the study population, stages 3b, 3c and 4 did not occur in the male sex before the 14th birthday, although the validity of the results is distinctly limited relative to stage 3b in view of the small number of cases. In females, stages 3c and 4 did not occur before the 14th birthday. Stage 4 did not occur in males before the 18th birthday. Should this result be confirmed in future studies, there would be an additional criterion providing evidence that the age of 18 years has been completed.

Virtual anthropology: useful radiological tools for age assessment in clinical forensic medicine and thanatology

“…MRI), it is clear that the use of machines with intrinsic differences (for example 1.5 or 3 Teslas), extrinsic differences: different sequences (T1 or T2 weighted images), different planes (coronal or sagittal), makes it difficult to compare results of the various studies, because the staging depends on all these parameters [24]. For example, higher magnetic field strengths may contribute to improve the signal-to-noise ratio, and potentially improving the quality of the images [13,25].…”

“…This exposure raises ethical concerns, even if the individual gives consent before the examination takes place. Bearing this in mind, non-invasive imaging procedures such as ultrasound examination (US) and magnetic resonance imaging (MRI) have recently been applied to minimize radiation exposure of the individual examined [11][12][13][14][15]. It is because of the need to compare the results with those of previous plain X-ray studies that anatomical areas such as the sternal end of the clavicle, the hand and wrist, and the iliac crest have been studied.…”

“…Compared with plain X-rays, MRI shows an earlier age at the beginning of the fusion process and an older age of complete fusion. Most MRI studies focusing on bone age assessment use T1-weighted sequences which provide a good indirect imaging of the bone and provide anatomical information [13,25]. One study used fast spin-echo proton density-weighted images, showing a different appearance of the growth plate compared with T1-weighted sequences [13,25,26].…”

“…But it is one of the two existing markers of the 18-year-old threshold, with fusion of at least twothirds of the sternal end of the clavicle on CT scan [32]. --Other anatomical areas have been studied, such as the iliac crest in male football players, the distal tibial epiphysis and the calcaneum [13,26,33,34]. Bayesian predictive probabilities were used to assess the usefulness of ankle and foot analysis for the 18-year-old threshold and showed excellent results for individuals over the age of majority (over 90 % of correct estimations), but risks of errors in minors (especially females, with more than 20 % of incorrect estimations) [34].…”

Magnetic resonance imaging of distal tibia and calcaneus for forensic age estimation in living individuals

“…The performance of MR imaging of the medial clavicular epiphysis [9][10][11][12], distal tibia and calcaneus [13,14], proximal tibial epiphysis [15], iliac crest [16], hand-wrist [17], and distal femur [18][19][20] has tended to increase in frequency, and research on the use of the medial clavicular epiphysis for age estimation has gained importance. Current data on the distal tibial and calcaneal epiphysis are based only on Xray methods [21][22][23][24][25].…”