Disc Prolapse
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Transcript of Disc Prolapse
DISC PROLAPSE
PRESENTED BY
VYOM GYANPURIM.P.T. (Ortho)
INTERVERTEBRAL DISC
STRUCTURE A central nucleus pulposus
Surrounded by peripheral annulus fibrosus
Two layers of cartilage which cover top and bottom aspect of each disc called a vertebral end plate
Its separate the disc from the adjacent vertebral body
NUCLEUS PULPOSUS
It is semi fluid mass of mucoid material seems like a tooth paste
It consist of few cartilage cells and irregular arranged collagen fibers
The fluid nature of nucleus pulposus allowed it to be deformed under pressure
The nucleus attempt to deformed and will there by transmit the applied pressure in all direction
ANNULUS FIBROSUS The annulus fibrosus consist
of collagen fibers.
The collagen fibers are arranged in between 10 to 20 sheets called lamellae.
These are arranged in concentric rings that surround the nucleus pulposus.
They are thick in anterior and lateral portion of the annulus but posteriorly they are finer and more tightly packed.
The collagen fibers lie parellel to each other.
VERTEBRAL END PLATES Each vertebral end plate
is a layer of cartiladge about 0.6-1 mm thick.
Covers the area on the vertebral area encircled by the ring apophysis.
Nucleus pulposus is entirely covered but annulus fibrosus is only 66% covered by the end plates.
PROLAPSE
The term prolapsed disc means the protrusion or extrusion of the nucleus pulposus through a rent in the annulus fibrosus.
It has a four stages
Bulging
Protrusion
Extrusion
sequestration
CAUSES Heavy manual labour
Repetitive lifting and twisting
Postural stress
Monotonous work
Lack of personal control on work
Poor physical fitness
Poor and inadequate strength of the trunk
Smoking
Aging process
Mechanical breakdown & loss of nutritional pathways
MECHANISM It only occurs if the disc has deteriorated as
a result of repeated microtraumas and if the annulus fibres have started to degenerate
Disc prolapse usually follows lifting of weight with the trunk flexed forward.
Disc prolapse occurs in three stages
First stage
Trunk flexion flattens the disc anteriorly and open out the intervertebral space posteriorly
Second stage
As soon as the weight is lifted the increased axial compression force crushes the whole disc and violently drives the nuclear substance posteriorly until it reaches the deep surface of PLL.
Third stage
With the trunk nearly straight , the path taken by the herniating mass is the closed by the pressure of vertebral plateaus and the hernia remains trapped under the posterior longitudinal ligament.
Prolapse occurs in two manners also
Sudden disc prolapse
Gradual disc prolapse
PATHOLOGY
Nucleus degeneration Degenerative changes occur disc before
displacement of the nuclear material.
These changes are :-
o Softening of the nucleus and its fragmentation
o Weakening and the disintegration of the posterior part of the annulus
Nucleus displacementThe nucleus is under positive
pressure at all times
When the annulus becomes weak, either because a small area of entire thickness has disintegrated spontaneously or because of injury, The nucleus tends to bulge out.
Stage of fibrosisThis is the stage of repair.
This begins alongside of degeneration. the residual nucleus pulposus become fibrosed.
The extruded nucleus pulposus becomes flattened,fibrosed and finally undergoes calcification.
Annular tearsThree types of annulus tears
Concentric(circumferential) tears
Tears between adjacent lamellae
Rim lesions
Focal circumferential avulsion of peripheral annulus
Radial fissure
Allows nucleus material to escape
STAGESBulging
At this early stage, the disc is stretched and doesn’t completely return to its normal shape when pressure is relieved. It retains a slight bulge at one side of the disc.
Some of the inner disc fibres could be torn and the soft jelly (nucleus pulposus) is spiling outwards into the disc fibres but not out of the disc
ProtrusionAt this stage, the bulge is very prominent and the soft jelly centre has spilled out to the inner edge of the outer fibres, barely held in by the remaining disc fibres.
Extrusion
In the case of a herniated spinal disc, the soft jelly has completely spilled out of the disc and now protruding out of the disc fibres.
Sequestration
Here some of the jelly material is breaking off away from the disc into the surrounding area
REFERENCES CLINICAL ANATOMY OF LUMBAR SPINE – BOGDUK
KINESIOLOGY OF THE JOINTS – KAPANDJI
CLINICAL ORTHOPAEDIC REHAB – BROTZMAN
ESSENTIAL ORTHOPAEDICS - MAHESWARI
THANKYOU