Morphogenesis, anatomy and histology of the ligamentum flavum

Spinal ligaments play a very important role in the mechanics of the spine. Curiously the ligamentum flavum (LF) has been the object of few specific studies. First a study on LF of foetuses has been carried out with anatomical, histological (classic staining techniques, immunohistochemistry and ultrastructural study) and radiological techniques. The LF is very different from the other spinal ligaments. It derives very early from a mesenchymeal tissue and not from the primitive muscular structures. Its development, its relations are very closed with lamina, capsules and tendons of spinal muscles. It is quickly an innervated and vascularized ligament with a predominance of elastic fibres. It is from a structural and functional point of view, by its two layers, the equivalent of a capsule and an articular ligament. Second, an ultrastructural and immunohistochemical study has been realized on adult LF to specify the kind of its innervation. It is innervated by fibres of great diameter, with myelin sheath. The positive immunomarking with neuropeptid Y is in favour of the proprioceptive type of this innervation. The LF has a specific and active role within the vertebral building, at the level of the spinal joints. Its characteristics described above confirm its neurological role especially for proprioceptive control. On the whole, this ligament is both mobilizing, stabilizing and adviser. The implications in spinal physiopathology are numerous

Complications following anterior approaches to the cervical spine. Review of 535 surgical procedures

The authors present a retrospective study of 535 consecutive anterior approaches to the cervical spine back to 5 years. The data were analyzed for post-operative complications. This surgical procedure has been commonly used for more than 40 years, but the post-operative complications due to the anterior approach itself were presented with few accompanying statistics, with various and contradictory results. Injury to nearly all of the structures has been reported in the literature, the more frequent problems are hoarseness and dysphagia; other complications include perforation of the oesophagus, hematomas, vascular injury... Analysis of this data allows to understand better the specific problems related to this surgical approach, and to suggest precautions at each stage of the course of exposure of cervical vertebrae

[Subacute osteomyelitis of the acetabulum]

A 15-months-old girl presented an excentration of the hip associated with a defect image of the acetabulum. Arthrography revealed a communication between the hip joint and the acetabular defect. Bacteriological specimens of the articular fluid were negative. The radiographic images were compatible with subacute osteomyelitis. Relative immobilization using an Atlanta abduction devise was undertaken. No medical treatment was prescribed for this adolescent who had received antibiotics for polymicrobial urinary tract infections and for pharyngitis prior to detection of the orthopedic disorder. Outcome was satisfactory with progressive filling of the acetabular defect but also with development of a subluxating coxa valga which required varus osteotomy of the femur. This case appears to illustrate a particular form of subacute osteomyelitis which is not described in earlier classifications

Ostéomyélite subaiguë de l'acétabulum.

A 15-months-old girl presented an excentration of the hip associated with a defect image of the acetabulum. Arthrography revealed a communication between the hip joint and the acetabular defect. Bacteriological specimens of the articular fluid were negative. The radiographic images were compatible with subacute osteomyelitis. Relative immobilization using an Atlanta abduction devise was undertaken. No medical treatment was prescribed for this adolescent who had received antibiotics for polymicrobial urinary tract infections and for pharyngitis prior to detection of the orthopedic disorder. Outcome was satisfactory with progressive filling of the acetabular defect but also with development of a subluxating coxa valga which required varus osteotomy of the femur. This case appears to illustrate a particular form of subacute osteomyelitis which is not described in earlier classifications.Nous rapportons le cas d’une fillette âgée de 15 mois présentant une excentration de la hanche associée à une image lacunaire de l’acétabulum. L’arthrographie mettait en évidence une communication entre l’articulation et la cavité du fond de l’acétabulum. Les prélèvements bactériologiques du liquide articulaire étaient négatifs. C’est l’analyse des images radiologiques qui a fait proposer le diagnostic d’ostéomyélite subaiguë. Une immobilisation relative à l’aide d’un appareil d’abduction de type Atlanta fut prescrite. Aucun traitement médical n’était administré chez cette enfant qui avait reçu des cures d’antibiotiques pour des infections urinaires polymicrobiennes ainsi que pour une pharyngite avant l’identification de son problème orthopédique. L’évolution a été satisfaisante avec un comblement progressif de la lacune mais apparition d’une coxa valga subluxante qui a justifié une ostéotomie de varisation du fémur. Nous pensons qu’il s’agit d’une forme particulière d’ostéomyélite subaiguë qui n’est pas décrite dans les classifications antérieures

The narrowing of the lumbar spinal canal during loaded MRI: the effects of the disc and ligamentum flavum

Load and activity changes of the spine typically cause symptoms of nerve root compression in subjects with spinal stenosis. Protrusion of the intervertebral disc has been regarded as the main cause of the compression. The objective was to determine the changes in the size of the lumbar spinal canal and especially those caused by the ligamentum flavum and the disc during loaded MRI. For this purpose an interventional clinical study on consecutive patients was made. The lumbar spines in 24 supine patients were examined with MRI: first without any external load and then with an axial load corresponding to half the body weight. The effect of the load was determined through the cross-sectional areas of the spinal canal and the ligamentum flavum, the thickness of ligamentum flavum, the posterior bulge of the disc and the intervertebral angle. External load decreased the size of the spinal canal. Bulging of the ligamentum flavum contributed to between 50 and 85% of the spinal canal narrowing. It was concluded that the ligamentum flavum, not the disc had a dominating role for the load induced narrowing of the lumbar spinal canal, a finding that can improve the understanding of the patho-physiology in spinal stenosis