|
Jean-Yves Maigne, MD
|
| Mise
en ligne : Novembre 2003 Dernière modification : 09.04.04 |
Anterior luxations are a rare lesion (less than 5% of the cases of coccydynia). They have nothing to see with posterior luxations, but should be considered as a more marked form of hypermobility. The difference lies in the axis of displacement of the luxated vertebra (usually the most distal one): there is no sagittal rotation (flexion) as in hypermobility but a slip in the sitting position. As in hypermobility, anterior luxations ocures in curved coccyges, with a low incidence and a high sagittal pelvic rotation.
![]() |
| Case #1: The anterior luxation typically involve the last vertebra. Is is rarely a complete luxation. |
![]() |
| Case #2: The diagnosis may be difficult. Here, the last but one joint (X) is involved. |
![]() |
| Case #3: This case is a combination of anterior luxation and hypermobility. This latter seems predominant. |
![]() |
| Case #4: Another typical case. |
![]() |
| Case #5: The need for excellent radiographs. Left : standard film. Center : dynamic film, which appears normal... but the distal vertebra is not seen. It is annoyin, because it was the one which was luxated (right, X) |
| How to take and read the dynamic films 1 |
| Posterior (intermitent) luxations 1 - 2 |
| Hypermobility 1 - 2 |
| Hypermobility in extension 1 |
| Spicules 1 - 2 - 3 |
| Anterior luxations 1 |
| Normal dynamic films |
| Complex lesions 1 |
| Fractures 1 |
| Calcifications, crystal disease 1 - 2 |
| Deformities 1 |
| Coccygeal anatomy |
| Clinical section |