Subluxation

A subluxation may have different meanings, depending on the medical specialty involved. It implies the presence of an incomplete or partial dislocation of a joint or organ.

An orthopedic subluxation of any joint will sometimes require medical attention to help relocate or reduce the joint. Nursemaid's elbow is the subluxation of the head of the radius from the annular ligament. Other joints that are prone to subluxations are the shoulders, fingers, kneecaps, ribs, wrists, ankles, and hips affected by hip dysplasia. A spinal subluxation can sometimes impinge on spinal nerve roots, causing symptoms in the areas served by those roots. In the spine, such a displacement may be caused by a fracture, spondylolisthesis, rheumatoid arthritis, severe osteoarthritis, falls, accidents and other traumas. This is common in Ehlers-Danlos Syndrome.

An ophthalmologic subluxation is called ectopia lentis, an ocular condition characterized by a displaced or malpositioned lens within the eye. Subluxated lenses are frequently found in those who have had ocular trauma and those with certain systemic disorders, such as Marfan syndrome, Ehlers–Danlos syndrome, Loeys-Dietz syndrome and homocystinuria. Some subluxated lenses may require removal, as in the case of those that float freely or those that have opacified to form cataracts.

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