Anatomical study of the paraspinal approach to the lumbar spine.

The original description of the paraspinal posterior approach to the lumbar spine was for spinal fusion, especially regarding lumbosacral spondylolisthesis treatment. In spite of the technical details described by Wiltse, exact location of the area where the sacrospinalis muscle has to be split remains somewhat unclear. The goal of this study was to provide topographic landmarks to facilitate this surgical approach. Thirty cadavers were dissected in order to precisely describe the anatomy of the trans-muscular paraspinal approach. The level of the natural cleavage plane between the multifidus and the longissimus part of the sacrospinalis muscle was noted and measurements were done between this level and the midline at the level of the spinous process of L4. A natural cleavage plane between the multifidus and the longissimus part of the sacrospinalis muscle was present in all cases. There was a fibrous separation between the two muscular parts in 55 out of 60 cases. The mean distance between the level of the cleavage plane and the midline was 4 cm (2.4-5.5 cm). In all cases, small arteries and veins were present, precisely at the level of the cleavage plane. We found it possible to easily localize the anatomical cleavage plane between the multifidus part and the longissimus part of the sacrospinalis muscle. First the superficial muscular fascia is opened near the midline, exposing the posterior aspect of the sacrospinalis muscle. Then, the location of the muscular cleft can be found by identifying the perforating vessels leaving the anatomical inter-muscular space.

Late spinal dislocation after treatment of spinal arteriovenous malformation. A case of Charcot spinal arthropathy.

Neuropathic arthropathy of the spine is a destructive condition of the spine which is secondary to a loss of the protective proprioceptive reflexes. In the majority of cases, it occurs in patients who have suffered from traumatic medullary lesions and is responsible for destruction of the vertebral bodies and considerable spinal deformity. We report a case of neurogenic lumbar arthropathy in a patient with a spinal arteriovenous malformation. This vascular lesion caused considerable disturbances of proprioception. The course was favorable with regard to the deformity after correction and fusion by posterior approach.

[Degenerative vertebral dislocation]. / Dislocation vertébrale dégénérative.

Degenerative vertebral dislocations (laterolisthesis) are responsible for progressive transverse intervertebral shift. These changes appear like a translation of the lateral edge of a vertebra compared to that of the underlying vertebra and are easily diagnosed. Vertebral dislocations can be secondary to active lumbar scoliosis or unilateral or asymmetrical degenerative spondylolisthesis. In every case, the appearance of laterolisthesis is reflected by the onset or aggravation of scoliosis which may become self-perpetuating. This lesion is secondary to osteoarthritic disruption of the integrity of the intervertebral disk and ligaments. Open and closed patterns have been described depending on the side of the associated disk opening. The onset of a rotatory dislocation reflects the progressive evolution of the deformity, which may require medical treatment, or surgical reduction and fixation by vertebral arthrodesis.