Mechanical Properties and Internal Disc Pressure of Human Intervertebral Joints

Abstract

Fifteen fresh, intact lumber intervertebral joints (L 3-L 4 disc body unit) from spines were loaded in an Instron type universal materials testing machine to determine their mechanical properties and internal disc pressure. Internal disc pressure was measured by a needle-type semiconductor pressure sensor. The measurements made included vertical load deformation and disc bulge in the anterior, lateral and posterior. The results showed that vertical deformation averaged 2.06 mm, and internal disc pressure was 0.52 MPa at 1000N : but internal disc pressure could not be measured in old aged samples.