1. The anatomical possibilities for the articular facets to play a more or less active part in the production of low-back pain with or without sciatic radiation are obvious, but pathological evidence is not yet sufficient to make this conclusion a fact.
2. Clinical evidence, in case of low-back pain with or without sciatic radiation, of pathology in or affecting the articular facets, requires serious consideration of the articulation in all cases of this syndrome.
3. The frequency of arthritis in the facets as age progresses, and the frequency of low-back disturbances in similar age periods, are coincidental facts of very probable significance.
4. Sciatica is a symptom complex, in which the syndrome is the only constant factor; the causative factors are variable and may be single or multiple, but the rôle of the facets should be considered in every case.
5. Rotation of the lumbar, and particularly of the lumbosacral articulation, occurs to a greater extent than anatomists have recognized. In this region it takes place chiefly in the facets, instead of in the intervertebral discs as it does in rotation in the thoracic region.