A subluxation is an incomplete or partial

dislocation In materials science, a dislocation or Taylor's dislocation is a linear crystallographic defect or irregularity within a crystal structure that contains an abrupt change in the arrangement of atoms. The movement of dislocations allow atoms to ...

of a joint or organ. According to the

World Health Organization The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level o ...

(WHO), a subluxation is a "significant structural displacement", and is therefore always visible on static imaging studies, such as X-rays. In contrast, the

chiropractic Chiropractic is a form of alternative medicine concerned with the diagnosis, treatment and prevention of mechanical disorders of the musculoskeletal system, especially of the spine. It has esoteric origins and is based on several pseudoscien ...

belief of " vertebral subluxation" may or may not involve a significant displacement or even pain or clear dysfunction.WHO guidelines on basic training and safety in chiropractic
p. 4, including footnote.

Joints

A subluxation of a joint is where a connecting bone is partially out of the joint. In contrast to a luxation, which is a complete separation of the joints, a subluxation often returns to its normal position without additional help from a health professional. An example of a joint subluxation is a nursemaid's elbow, which is the subluxation of the head of the

radius In classical geometry, a radius ( : radii) of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length. The name comes from the latin ''radius'', meaning ray but also the ...

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 is visible on X-rays and 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 Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects synovial joint, joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and ...

, severe osteoarthritis, falls, accidents and other traumas. This is common in Ehlers–Danlos Syndrome.

Lens of the eye

A subluxation of the

lens A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements'' ...

within the

eye Eyes are organs of the visual system. They provide living organisms with vision, the ability to receive and process visual detail, as well as enabling several photo response functions that are independent of vision. Eyes detect light and conv ...

is called ectopia lentis, wherein it is displaced or malpositioned. 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 Loeys–Dietz syndrome (LDS) is an autosomal dominant genetic connective tissue disorder. It has features similar to Marfan syndrome and Ehlers–Danlos syndrome. The disorder is marked by aneurysms in the aorta, often in children, and the aort ...

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.

Teeth

A subluxation of a tooth is a

dental trauma Dental trauma refers to trauma (injury) to the teeth and/or periodontium (gums, periodontal ligament, alveolar bone), and nearby soft tissues such as the lips, tongue, etc. The study of dental trauma is called dental traumatology.''Textbook and C ...

tic injury in which the

tooth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, t ...

has increased mobility but has not been displaced from the mandible or

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The ...

. This is a common condition and one of the most common dental traumatic disorders. Dental subluxation is a non-dental-urgency condition, i.e., unlikely to result in significant morbidity if not seen within 24 hours by a dentist, and usually treated conservatively: good oral hygiene with 0.12% chlorhexidine gluconate mouthwash, a soft and cold diet, and avoidance of smoking for several days. In painful situations, a temporary splinting of the injured tooth may relieve the pain. Subluxation may also occur in the mandible from the articular groove of the temporal bone. The mandible can dislocate in the anterior, posterior, lateral, or superior position. Description of the dislocation is based on the location of the condyle in comparison to the temporal articular groove.

References

{{Reflist Medical terminology Dislocations, sprains and strains Joints Orthopedic surgical procedures Ophthalmology Acquired tooth disorders Bones of the vertebral column