STUDY DESIGN: Cadaveric head-neck complexes from pediatric donors aged 2-12 years were subjected to a test battery consisting of nondestructive flexion-extension bending, nondestructive tensile step-and-hold tests, and tensile distraction loading to failure. OBJECTIVE: To characterize the biomechanical response of the pediatric cervical spine in flexion-extension bending, and the response and tolerance of the pediatric cervical spine in tensile distraction loading. SUMMARY OF BACKGROUND DATA: Except for a 19th century study on stillborn infants, to our knowledge, there are no published data from human cadaveric studies on the response and tolerance of the pediatric cervical spine. METHODS: Ten unembalmed pediatric head-neck complexes with intact ligamentous cervical spines were sectioned from pediatric donors aged 2-12 years. Each specimen was potted at the level of T2 and subjected to quasi-static nondestructive flexion-extension bending by a pure moment applied to the neck. Following the flexion-extension testing, each specimen was preconditioned in tension and subjected to a series of nondestructive tensile step-and-hold tests followed by tensile distraction loading to failure using a mini-Bionix MTS machine (MTS Systems Corp.). RESULTS: The average +/- standard deviation rotational stiffness of the skull-C2, C2-T2, and skull-T2 spinal segments was 0.72 +/- 0.07, 0.07 +/- 0.02, and 0.04 +/- 0.01 Nm/degree, respectively. Average rotational stiffness was independent of age for the range of pediatric ages tested. In the destructive tensile tests, failure occurred at an average distraction force of 726 +/- 171 N and an average distraction displacement of 20 +/- 3 mm. The average ultimate distraction force recorded for the 2-4-year-old specimens (595 +/- 143 N) was significantly lower (P < 0.05) than the corresponding average recorded for the 6-12-year-old specimens (868 +/- 71 N). Average +/- standard deviation linear stiffness in tensile loading was 34.7 +/- 5.7 N/mm. Pediatric age did not have a statistically significant effect on the average linear stiffness. CONCLUSIONS: The current study provides valuable new information on the response and tolerance of the pediatric cervical spine to quasi-static flexion-extension and tensile distraction loading.
STUDY DESIGN: Cadaveric head-neck complexes from pediatric donors aged 2-12 years were subjected to a test battery consisting of nondestructive flexion-extension bending, nondestructive tensile step-and-hold tests, and tensile distraction loading to failure. OBJECTIVE: To characterize the biomechanical response of the pediatric cervical spine in flexion-extension bending, and the response and tolerance of the pediatric cervical spine in tensile distraction loading. SUMMARY OF BACKGROUND DATA: Except for a 19th century study on stillborn infants, to our knowledge, there are no published data from human cadaveric studies on the response and tolerance of the pediatric cervical spine. METHODS: Ten unembalmed pediatric head-neck complexes with intact ligamentous cervical spines were sectioned from pediatric donors aged 2-12 years. Each specimen was potted at the level of T2 and subjected to quasi-static nondestructive flexion-extension bending by a pure moment applied to the neck. Following the flexion-extension testing, each specimen was preconditioned in tension and subjected to a series of nondestructive tensile step-and-hold tests followed by tensile distraction loading to failure using a mini-Bionix MTS machine (MTS Systems Corp.). RESULTS: The average +/- standard deviation rotational stiffness of the skull-C2, C2-T2, and skull-T2 spinal segments was 0.72 +/- 0.07, 0.07 +/- 0.02, and 0.04 +/- 0.01 Nm/degree, respectively. Average rotational stiffness was independent of age for the range of pediatric ages tested. In the destructive tensile tests, failure occurred at an average distraction force of 726 +/- 171 N and an average distraction displacement of 20 +/- 3 mm. The average ultimate distraction force recorded for the 2-4-year-old specimens (595 +/- 143 N) was significantly lower (P < 0.05) than the corresponding average recorded for the 6-12-year-old specimens (868 +/- 71 N). Average +/- standard deviation linear stiffness in tensile loading was 34.7 +/- 5.7 N/mm. Pediatric age did not have a statistically significant effect on the average linear stiffness. CONCLUSIONS: The current study provides valuable new information on the response and tolerance of the pediatric cervical spine to quasi-static flexion-extension and tensile distraction loading.
Authors: D Davidson Jebaseelan; Chidambaram Jebaraj; Narayan Yoganandan; S Rajasekaran Journal: Med Biol Eng Comput Date: 2010-10-23 Impact factor: 2.602
Authors: Sebastiaan P J Wijdicks; Justin V C Lemans; Gijsbertus J Verkerke; Herke Jan Noordmans; René M Castelein; Moyo C Kruyt Journal: Eur Spine J Date: 2020-10-06 Impact factor: 3.134