Magnetic resonance imaging (MRI) showed diffuse bulge with bilateral foraminal components of L4-L5 disc with ligamentum flavum
hypertrophy and facetal arthropathy, diffuse bulge of L3-L4 disc, also marked ligamentum flavum
hypertrophy and thickening at L3-L4.
Cervical spondylotic myelopathy (CSM) results from degenerative arthritis of cervical spine giving rise to posterior spondylotic ridges or osteophytes, disc herniation, facet joint arthropathy and ligamentum flavum
hypertrophy/ buckling causing cervical cord compression and myelopathic changes.
The model of the segmented vertebral bodies, ligaments (anterior longitudinal, posterior longitudinal, supraspinal (SSL), interspinal (ISL), ligamentum flavum
, and intertransverse), intervertebral discs, and ribs were imported into a finite element analytical program (ABAQUS 6.11 Simulia, USA) for simulation and quantitative analysis.
During PTED, the nerve root can be decompressed under direct vision without destroying the integrity of posterior spine structure, also retaining the ligamentum flavum
as well as reducing clinical symptoms caused by postoperative bleeding, adhesion and scar formation.
The dorsal epidural space (Figure 1) at the interlaminar level is the target site for injection, just deep to the ligamentum flavum
. Relevant anatomic landmarks of the lumbar vertebrae including the posterior element components, interlaminar spaces, spinal canal margins, and disc spaces must all be identified by the operator (Figure 2).
Several studies have radiologically examined flavum ligament thickness and its association with age and lumbar levels in the early stages of degenerative cascade; examining the relationship of the inflammatory process with the occurrence of ligamentum flavum
thickening and so on (1,3,4).
hypertrophy was also evident at this level.
Study authors from the Citta di Roma Hospital and Careggi Hospital in Italy, conclude, "We [have] validated the CompuFlo device as a means of adequately identifying the ligamentum flavum
and the epidural space.
From this stage in OD, using a curette, the ligamentum flavum
was retracted and dropped from the insertion point to the lamina, the spinal cord and nerve roots were seen after partial laminectomy and removal of the ligamentum flavum
, and the nerve root was made completely visible after opening the foramen.
The epidural space is a potential space, and the ligamentum flavum
and dura mater are usually seen as a single hyperechoic structure in the midline, which is called as the ligamentum flavum-dura mater unit or the ligamentum flavum-dura mater complex (posterior complex).
There is also disruption of the ligamentum flavum
(double up-down arrows).
Various risk factors have been associated with ID like increasing age, large disk, complexity of the procedure, hypertrophy of the ligamentum flavum
, repeat spinal surgery and decreased experience of the operating surgeon.