Derotation

Derotation refers to the process of returning a structure from a rotated position to its normal orientation. The term is used across medical and dental specialties to describe corrective rotation procedures or the correction of rotated teeth. It encompasses surgical, non-surgical, and orthodontic approaches aimed at restoring functional alignment.

In orthopedics, derotation is performed to correct rotational deformities such as femoral anteversion, tibial torsion, or humeral retrotorsion. Diagnosis typically involves physical examination and imaging to measure torsion angles, sometimes using CT or MRI. Indications include gait abnormalities, functional impairment, and cosmetic concerns. Methods include derotational osteotomy, where a bone segment is rotated to the desired version and stabilized with plates, screws, or external fixators. In some cases, gradual derotation is achieved with external fixation or casting. Outcomes vary with age, the underlying condition, and accuracy of the correction; possible complications include relapse and nerve or vascular injury.

In dentistry and orthodontics, derotation describes correcting rotated teeth. Fixed appliances (braces) or removable aligners are used to apply forces that unwind malrotations. Treatment may involve auxiliary wires, elastics, or temporary anchorage devices. The duration depends on the severity of rotation and the overall treatment plan, and relapse can occur if retainers are not used after correction.

In ophthalmology, derotation can refer to correcting rotational misalignment of the eye, such as cyclodeviation, during strabismus surgery. Techniques may involve adjusting the actions of extraocular muscles to achieve proper ocular alignment and binocular visual function.

Overall, derotation is a corrective concept applied when rotational deformities compromise function or appearance, with approaches tailored to the involved tissue and clinical goals.