Lumbar spinal instability is frequently referred to in clinical practice and literature; however, there is no real standard of definition or validated radiographic test (Hipp et al., 2015).
Lumbar Instability refers to the inability of the stabilising muscles of the spine to perform their role effectively in providing support and strength to the vertebral column.
This is typically a complication of a degenerative lumbar disc, however it may also occur in hypermobile individuals. Dynamic X-rays are widely recognized to detect lumbar instability in individuals (Landi et al., 2015). Pain usually occurs from the paravertebral musculature, especially in standing, when the muscles tighten and seize up in order to prevent the hypermobile segment (Landi et al., 2015).
Symptoms are typically present through movement of the lumbar spine eg; forward flexion may produce symptoms on bending or returning from the bent position but may not be present at end of range positions. It may have been caused by a series of minor or traumatic events. The accumulation of the injuries is generally believed to cause the degeneration of a disc which leads to the increased joint movement that the surrounding musculature cannot control.
Research has shown, that patient with lumbar instability also show restricted hip movement; therefore, hip/pelvic girdle exercises in order to strengthen the lumbar spine are a good basis for exercising and reducing low back pain (Lee and Kim, 2015). Fusion of the unstable segment is the last consequence in a surgical procedure.
Landi A. et al., 2015, Hidden spondylolisthesis: unrecognized cause of low back pain? Prospective study about the use of dynamic projections in standing and recumbent position for the individuation of lumbar instability, Springer, 57(6), pp: 583-588
Lee S. and Kim S.Y., 2015, Effects of hip exercises for chronic low back pain patients with lumbar instability, Journal of Physical Therapy Science 27(2), pp: 345-348
Hipp J.A. et al., 2015, Development of a novel radiographic measure of lumbar instability and validating using the facet fluid sign, International Journal of Spine Surgery, 9(37), doi: 10.14444/2037