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Flexion

About 50* of flexion occurs in a normallumbar spine.

The range of flexion increases from cranialto caudal dirrection.

Pelvic-on- femoral flexion causes

increased tension in hamstrings and contflexion in lumbar region reverses naturallordosis at low back.

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Inferior articular facets of one superiorlumbar vertebra( for eg.L2) slide

anteriorly and superiorly as compared tosuperior facets of the inferior(for eg. L3).

Intervertebral disks are compressed and

post lig tensed. Prolonged slouch posture may cause

overstretching of capsules of apophysealjoints.

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Extension

It increases the natural lordosis andcombined with hip extension it causes the

tensed hip flexors and lig to maintain theant pelvic tilt and thereby lumbarextension.

Facets move in exactly opposite direction

for eg a sup L2 facet will slide inf and supin relation to the sup articular facet of L3 Full extension increases the load and

contact area of apophyseal joints.

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Rotations

Only 5 degrees of rotation is possible inlumbar region on either side.

For eg. Rotation to right- joint seperationonto right side and compression to the leftside.

The biomechanical resistance to rotationincreases the vertical stability of lumbarspine which is reinforced by multifidusand SI joint.

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Lateral Flexion

15-20 degrees on either side.

Limited by contralateral soft tissues.

Lateral flexion to one side is generallyaccompanied by opposite side rotations ofvertebra.

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ROM

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Lumbo-pelvic

Rhythm

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Lumbopelvic Rhythm-Flexion

Normal- Lumbar spine and hips(pelvis onhips) flex simultaneously.

Tight Hamstrings-Lumbar spinecompensates by increasing lumbarflexion.

Limited lumbar flexion- Excessive hipflexion with a flat back.

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Lumbopelvic Extension

Normal- Initiated from hips andcompleted by lumbar extension.

Delayed lumbar extension causes theextension torque demands to be shiftedonto more powerful muscles likehamstrings and glut max.

Weak hip ext will therefore put load onthe weak lumbar extensors to overcomethe torque demands and cause pain andinjury.

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Effect of pelvic tilt on LumbarSpine

Ant pelvic tilt- causes lumbar extension It shifts nucleus pulposes ant.

Post Pelvic Tilt- causes lumbar flexion It shifts nucleus pulp. Post. The posture of lumbar and pelvis affects

the entire axial skeleton posture. Generally seen with slouch posture is

forward head posture.

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THANK YOU

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