Intervertebral body fusion devices are a promising biomedical application for metal foams. A new Titanium foam made by powder metallurgy was developed and biomechanically assessed to determine its applicability to spinal fusion implants. Mechanical behaviour of a lumbar spinal cage made of this new Ti foam was evaluated under different loading conditions and compared to other cages with similar geometry but different materials. An implantation study was carried out to assess the osseointegration ability of the Ti foam. Bone ingrowth and fixation strength of porous Ti were compared to those of dense Ti with plasma-sprayed Ti and Hydroxyapatite porous coating through push-out mechanical tests and histological analysis. Ti foam implants show high mechanical strength and fatigue endurance. Their stiffness is much closer to that of trabecular bone than solid alloys usually applied to orthopaedic implants. Osseointegration study reveals bone ingrowth inside Ti foam and high bonding strength for this material. However, bone fixation strength is lower than that obtained by solid plasma-sprayed coated implants.
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