Retrieval Analysis of Cervical and Lumbar Total Disc Replacements – A Study of In Vivo Wear, Surface Properties, and Fixation


Darren R. Lebl, MD
Celeste Abjornson, PhD

Project Description

Degenerative disc disease is a common surgical problem in both the cervical and lumbar spine. Long-term results of fusion procedures have demonstrated adjacent segment degeneration (ASD) in a large percentage of patients. Motion-preserving cervical and lumbar total disc replacement technology (CTDR and LTDR, respectively) is proliferating due to encouraging early results of prospective clinical studies. At the current nascent stages of CTDR/LTDR clinical experience, there remains a paucity of data on in vivo device performance. To understand their in vivo kinematics, we are performing a prospective analysis of retrieved CTDR/LTDR devices. We hypothesized that the resection of the anterior longitudinal ligament (ALL) necessary for TDR implantation results in evidence of posterior impingement and the higher loads seen in the lumbar spine facilitate polyethylene wear. Explanted Prodisc-L and Prodisc-C devices from surgeons nationwide are cleaned and catalogued according to an IRB-approved retrieval program. PE and metallic(CoCrMo) components were examined using light stereo-microscopy for wear, surface damage, and bone ongrowth. Areas of interest were evaluated at higher magnifications using scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDXA). Results are reported as mean ± standard error. Categorical data was compared using Pearson’s Chi-squared.

The student will work with the group to analyze incoming retrievals. The student will prepare case reports of the retrieved implants and work with the team in understanding the trends of the collection.

This Position Has Been Filled.