title: Age changes in the lumbar articular triad.
abstract: The articular triad of the intervertebral disc and the two synovial zygapophyseal joints at the same vertebral level, allows the spine its considerable mobility, while providing support and protection. The principal structural changes which occur to the elements of the articular triad in old age are an increase in the convexity, central height and horizontal intervertebral disc dimensions, and increased swelling and fibrillation of zygapophyseal joint cartilage with expansion of joint margins by osteophytes. These changes are directly responsible for the reduction in the ranges of all lumbar movements in old age. Advanced osteoarthrosis in old age is not accompanied by bony sclerosis, because of the generalized osteopenia of old age.
authors.forename: L T
authors.initials: LT
authors.lastname: Twomey
authors.forename: J R
authors.initials: JR
authors.lastname: Taylor