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We validate a technique for measuring neural arch load-bearing in cadaveric spines, and use it to test the hypothesis that such load-bearing rises to high levels in old and degenerated spines. Fifty-nine cadaveric lumbar motion segments, aged 19–92yr, were subjected to compressive creep loading to reduce intervertebral disc water content and height to in vivo levels. The distribution of compressive “stress” within the disc was then measured by pulling a miniature pressure transducer, side-mounted in a 1.3mm-diameter needle, along its mid-sagittal diameter. During these measurements, the motion segment was subjected to a compressive load of 2kN, and positioned in 2° of extension to simulate erect standing. Measurements of compressive “stress” were integrated over disc area, and this force subtracted from the applied 2kN to give the force resisted by the neural arch. An empirical calibration factor was applied …