Slide 1 Spinal Stability Tara Jo Manal PT, SCS, OCS

Slide 2 Clinical Instability Loss of the ability of the spine under physiologic loads to maintain its pattern of displacement so that there is no initial or additional neurological deficit, no major deformity, and no incapacitating pain Loss of the ability of the spine under physiologic loads to maintain its pattern of displacement so that there is no initial or additional neurological deficit, no major deformity, and no incapacitating pain »White and Panjabi

Slide 3 Clinical Instability Anatomic Considerations Anatomic Considerations Biomechanical Factors Biomechanical Factors Clinical Considerations Clinical Considerations Treatment Considerations Treatment Considerations Recommended Evaluation system Recommended Evaluation system Recommenced management Recommenced management –Recorded cases of patient post-polio with cervical paralysis and no instability if bones and ligaments remain intact

Slide 4 Biomechanics of Spinal Cord and Nerve Roots Cord does not slide up and down (v.small) Cord does not slide up and down (v.small) Accordion like- lengthen on one side and shorten on the other (ie sidebending) Accordion like- lengthen on one side and shorten on the other (ie sidebending) Greatest stretching occurs between C2 and T1 (<20%) Greatest stretching occurs between C2 and T1 (<20%) Injury is due to loss of cord elasticity, displacement or space occupying lesions Injury is due to loss of cord elasticity, displacement or space occupying lesions High compliance in the axial plane, less in the horizontal plane High compliance in the axial plane, less in the horizontal plane

Slide 5 Types of Instability Kinematic Kinematic –Motion increased –Instantaneous axes of rotation altered –Coupling characteristics changed –Paradoxical motion present Component Instability Component Instability –Trauma –Tumor –Surgery –Degenerative changes –Developmental chages

Slide 6 C0-C1 Unstable in childhood Unstable in childhood Dislocations are generally fatal Dislocations are generally fatal Instability identified by x-ray Instability identified by x-ray –Rotation >8° is pathological –Translation > 1 mm

Slide 7 C1-C2 Instability due to dens fracture Instability due to dens fracture Vertebral translation or Rotation Vertebral translation or Rotation Bone spur Bone spur Little contribution of the facet/capsule compared to dens and ligamentous ring Little contribution of the facet/capsule compared to dens and ligamentous ring Alar ligament test Alar ligament test –C1-C2 > 56° is abnormal

Slide 8 Jefferson Fracture C1 Ring Distruption, overhang of lateral masses of C2

Slide 9 C2-T1 Failure consists of injury to posterior and anterior elements Failure consists of injury to posterior and anterior elements Unilateral facet Unilateral facet –Root symptoms Bilateral facet Bilateral facet –Spinal medullary injury Burst Fracture Burst Fracture –Horizontal displacement –Spinal cord injury

Slide 10 Recognizing Instability History of a flexion injury History of a flexion injury Widening of interspinous space Widening of interspinous space Subluxation of a facet joint Subluxation of a facet joint Compression fracture of adjacent vertebrae Compression fracture of adjacent vertebrae Loss of normal cervical lordosis Loss of normal cervical lordosis

Slide 11 Thoracic Instability T1-T10 T1-T10 Overall greater stiffness Overall greater stiffness Spinal cord damage with injury ~10% Spinal cord damage with injury ~10% T11-L1 T11-L1 Spinal cord damage with injury ~4% Spinal cord damage with injury ~4%

Slide 12 Lumbar Instability L1-S1 L1-S1 3% Fracture and dislocation have neurological signs 3% Fracture and dislocation have neurological signs Disconnect between displacement and neurological signs Disconnect between displacement and neurological signs >4.5mm or 15% >4.5mm or 15% Facet has a crucial role in stability (rot and SB) Facet has a crucial role in stability (rot and SB)

Slide 13 Stabilization of the Spine Passive system Passive system Active system Active system Neural control Neural control

Slide 14 Muscular Control of the Spine Rotatores and Intertransversarii Rotatores and Intertransversarii Function primarily as force transducers Function primarily as force transducers Position Sensors Position Sensors Electrically silent with large rotations (involving Abs) Electrically silent with large rotations (involving Abs)

Slide 15 Muscular Control of the Spine Extensors – Longissimus, Iliocostalis Extensors – Longissimus, Iliocostalis Thoracic area ~75% slow twitch fibers Thoracic area ~75% slow twitch fibers Lumbar area ~50% mix Lumbar area ~50% mix Lumbar area- in flexion provide a compressive force in the lumbar to limit shear Lumbar area- in flexion provide a compressive force in the lumbar to limit shear

Slide 16 Muscular Control of the Spine Extensors – Multifidi Extensors – Multifidi Span only a few joints Span only a few joints Produce extensor torque/resistance Produce extensor torque/resistance Only small amounts of rotation or SB Only small amounts of rotation or SB Contribute to correction or support Contribute to correction or support

Slide 17 Muscular Control of the Spine Abdominal Muscles Abdominal Muscles Rectus Rectus –Major trunk flexor –Active with sit-up and curl-ups –Little to no evidence to support upper/lower differentiation

Slide 18 Muscular Control of the Spine Abdominal Wall- Ext/Int Oblique Abdominal Wall- Ext/Int Oblique Torso Rotation and Lateral flexion Torso Rotation and Lateral flexion

Slide 19 Muscular Control of the Spine Abdominal Wall-Transverse abdominis Abdominal Wall-Transverse abdominis Beltlike support and generation of intra- abdominal pressure Beltlike support and generation of intra- abdominal pressure Delayed onset during ballistic movements in patient’s with LBP Delayed onset during ballistic movements in patient’s with LBP

Slide 20 Muscular Control of the Spine Psoas Psoas Primarily hip flexor Primarily hip flexor Compressive force to spine during contraction Compressive force to spine during contraction Questionable contribution to spine stability Questionable contribution to spine stability If so, under high hip flexor forcesIf so, under high hip flexor forces

Slide 21 Muscular Control of the Spine Quadratus Lumborum Quadratus Lumborum Highly involved with spine stabilization Highly involved with spine stabilization Active in flexion, extension and SB Active in flexion, extension and SB During Lifting, increased oblique activity followed increases in QL During Lifting, increased oblique activity followed increases in QL

Slide 22 Muscular Control of the Spine Deep Rotators- position sensors Deep Rotators- position sensors Extensor Group Extensor Group –Generate large extensor moments –Generate posterior shear –Affect one or two segments

Slide 23 Co-activation of the Muscular Spine  90N force (20lbs) creates buckling without muscular forces  Co-contraction increases support against buckling

Slide 24 Muscular Stability Continuous contraction Continuous contraction ~10% MVIC of abdominals ~10% MVIC of abdominals No single muscle is critical one No single muscle is critical one

Slide 25 Joint Shear Testing

Slide 26 Generalized Ligamentous Laxity Elbow Hyperextension >10° Elbow Hyperextension >10° Passive Hyperextension of 5 th finger >90° Passive Hyperextension of 5 th finger >90° Abduction of thumb to forearm Abduction of thumb to forearm Knee Hyperextension >10° Knee Hyperextension >10° Forward flexion hands to floor (knees ext) Forward flexion hands to floor (knees ext) Tested Billateral: Total score: /9 Tested Billateral: Total score: /9

Slide 27 Neutral Spine

Slide 28 Abdominal Bracing

Slide 29 Curl-up Beginner Maintain lordosis with hands Maintain lordosis with hands Attempt to lift head (little to no motion) Attempt to lift head (little to no motion) Raise head and shoulders (no cervical flexion) Raise head and shoulders (no cervical flexion) One leg flexed one extended One leg flexed one extended

Slide 30 Curl-up Intermediate Elbows off the table Elbows off the table

Slide 31 Curl-up Advanced Fingers on forehead Fingers on forehead

Slide 32 Side Bridge Remedial

Slide 33 Side Bridge Reverse Lift legs off the bed Lift legs off the bed

Slide 34 Side Bridge Knees Flexed Knees flexed Knees flexed

Slide 35 Side Bridge Intermediate Legs extended Legs extended

Slide 36 Side Bridge Intermediate Variation Legs extended Legs extended Rolling of torso on legs Rolling of torso on legs

Slide 37 Side Bridge Advanced

Slide 38 Birddog, Remedial Hands and knees, raise one hand off bed Hands and knees, raise one hand off bed Progress to hand and opposite knee Progress to hand and opposite knee

Slide 39 Birddog, Beginner’s Raise one arm or leg at a time Raise one arm or leg at a time

Slide 40 Birddog, Intermediate Raise one arm and leg at a time Raise one arm and leg at a time Hold 6-8 seconds Hold 6-8 seconds

Slide 41 Birddog, Advanced Raise one arm or leg at a time Raise one arm or leg at a time Avoid Returning to the bed, sweep and resume Avoid Returning to the bed, sweep and resume

Slide 42 Isometric Rotation Isometric Activity Isometric Activity