Lumbar Spine Osteology and Disk

Question 1

Describe bony make up of lumbar vertebral bodies

Answer 1

Block of trabecular/ spongy bone covered by cortical bone

Question 2

Function of pedicles in lumbar spine

Answer 2

Transmit tension and bending forces from posterior elements to the vertebral body (e.g. ligaments)
Act as a lever for skeletal muscle

Question 3

Mammillary process of lumbar vertebra

Answer 3

• On transverse process/ superior articular process

- Where multifidi attach

Question 4

Pars Interarticularis

Answer 4

• Common site for stress fracture

- Between superior and inferior articular processes

Question 5

Describe Laminae of lumbar vertebrae

Answer 5

Thick –> Can encroach on spinal cord

Question 6

Function of spinous processes in lumbar vertebrae

Answer 6

Attachment of ligaments

Question 7

Orientation of facet surfaces in lumbar vertebrae favors:

Answer 7

Flexion and extension

Question 8

Superior Facets in lumbar vertebrae

Answer 8

• Concave

- Face medial/ posteromedial

Question 9

Inferior Facets in lumbar vertebrae

Answer 9

• Convex

- Lateral/ anteriolateral

Question 10

5th lumbar vertebra

Answer 10

• Body is wedge shaped (greater height anteriorly)
• Shape helps counter anterior sheer
• L5-S1 is a site with increased stress to disc

Question 11

Lumbar Spondylosis

Answer 11

Degenerative changes

• Facet joints: Osteophytes and joint hypertrophy –> Pressure on ligaments (pain) and stiffness
• Vertebral bodies: Osteophytes
• Intervertebral Disc: Thinning (dehydration), breakdown of annulus and excessive motion of pulposus

**Pain and stiffness

Question 12

Management of lumbar spondylosis

Answer 12

General: Unload Structures

• Extension loads the bones the most –> Pts will like flexion
• Postural education: Neutral spine/ wherever pt is most comfortable is optimal. This may be some flexion
• Joint mobilization to reduce pain and increase motion
• Traction (manual or mechanical)
• Core stabilization (TA) in functional positions with optimal posture

Question 13

Non-PT management of lumbar spondylosis

Answer 13

• Facet injection
  
  • Benefit = sxs decrease
  • Limit: Temporary; pt doesn’t change dysfunctional movement
• Surgical stabilization –> unpredictable outcomes

Question 14

Types of lumbar stenosis

Answer 14

Central (central canal) or

Lateral (intervertebral foramen)

Question 15

Central canal dimensions (normal vs. stenosis)

Answer 15

Normal: 15 to 23 mm
Narrowing: 10-12 mm

–> can compress spinal cord or spinal nerve roots

Question 16

Signs of lumbar spine stenosis

Answer 16

• Postural adjustments to get comfortable
• Walk with flexed posture
• Pain with lumbar extension (or even neutral)

Question 17

Symptoms of lumbar spine stenosis

Answer 17

• Radicular ache/ cramp into lower limbs when in extension
• AKA Neurogenic claudication (gets worse the longer pt is in extension)

Diagnosis:
Increase incline on treadmill. This will make pts with stenosis feel better, because they have to lean forward into flexion as incline increases

Question 18

Lumbar spinal stenosis management

Answer 18

Flexion progression:

• Supine or seated
• Teach patient positions of flexion to work in

Stretch hip flexors:

• Tight hip flexors will –> ant pelvic til –> lumbar extension
• Stretch on plinth - helps isolate hip flexors and keep pts from cheating by extending back

Strengthen core musculature: TA in neutral or flexed

Surgery: Laminectomy

Question 19

Spondylolysis

Answer 19

• Usually younger population
• Stress fracture in pars interarticularis
• Typically aggravated with extension activities

Question 20

4 potential causes of spondylolysis

Answer 20

1. Mechanical (Excessive extension)
2. Congenital
3. Traumatic (MVA)
4. Pathologic (Osteoporosis, bone mets)

Question 21

Spondylolysis diagnostic test

Answer 21

Single leg hyperextension test

• Used by other medical providers more than PT
• Metrics are questionable

Test:

• Stand on one leg
• Extend the spine
• Positive: Pt’s sxs are reproduced

Question 22

Management of spondylolysis

Answer 22

• Avoid extension
• Rest, initially

Brace
Core stability training
Flexibility of hip flexors
Modified movement/ training patterns (after period of rest) - avoid extension

Question 23

Bracing for spondylolysis

Answer 23

1. Boston Brace
   - Customized, less mobile
2. Warm n form
   - Temporary
   - Make in clinic
   - More mobile

Question 24

Spondylolisthesis

Answer 24

Forward slippage of one superior vertebra as a result of instability caused by BILATERAL defect in pars interarticularis
“scotty dog decapitated”

–> Stress on sacral nerve roots –> leg pain

Question 25

Spondylolisthesis signs and sxs

Answer 25

- Pain with extreme motion, esp extension - Pain generally follows belt line - May be able to palpate step off along spinous process

Question 26

Spondylolisthesis diagnosis

Answer 26

- L4-5, L5-S1 most common - Slippage determined by XRay - 4 Grades, according to percent of shift across vertebra I. 0-25% II. 25-50% III. 50-75% IV. 75-100% (III and IV are surgical candidates)

Question 27

Spondylolisthesis management

Answer 27

- Symptom management (modalities) - Lumbar core stabilization - Fusion surgery to prevent further slippage (if grade III or IV)

Question 28

Lumbar compression fracture

Answer 28

Less common than thoracic compression fx * Lumbar: Traumatic etiology * Thoracic: Osteoporosis

Question 29

Management of Vertebral Fx

Answer 29

- Vertebroplasty or Kyphoplasty - Flexibility - Strength (core and lower limbs) - Function (teach body mechanics)

Question 30

Vertebroplasty

Answer 30

Cement-like material is injected directly into fractured bone - Stabilizes fx and provides immediate pain relief in many cases

Question 31

Kyphoplasty

Answer 31

Includes additional step past vertebroplasty - Prior to injecting cement-like material, a special balloon is inserted and gently inflated inside the fractured vertebra - Balloon is removed before cement is places Goal of extra step is to restore height to the bone --> reducing deformity of spine

Question 32

Intervertebral Disk

Answer 32

- 20-33% of length of spinal column - 3 mm thick in cervical spine, 9 mm thick in lumbar spine Relevance to interbody joints (intervertebral disk, adjacent vertebral bodies, and vertebral endplates) - When disk dehydrates, facet joints take more pressure

Question 33

Disk Anatomy - NP

Answer 33

70-90% Water Type I and II collagen (mostly II) Loads like a balloon

Question 34

Disk Anatomy - Annulus fibrosis

Answer 34

- Collagen arranged in concentric rings (laminae) - Adjacent rings have opposite orientation to each other --> Helps protect NP during rotation - Role: Tension, keeps NP in place

Question 35

Disk Anatomy - Vertebral end plate

Answer 35

- Articular cartilage | - Attaches to AF and vertebral body

Question 36

Intradiscal pressure depends on

Answer 36

- Position and properties of disk - Applied load - Under prolonged low level loading, disks exhibit creep (e.g. in sitting) --> Pts get stuck in flexion Loads to failure will cause endplate fracture before disk rupture Bending loads include sitting, yard work

Question 37

Lumbar disk injury

Answer 37

- Inherent to anatomy (mobility vs. stability) - Common mechanism of injury: Flexion, rotation, and loading - Posterior-lateral injury to the disk - Injury to lamella allows nucleus to protrude

Question 38

Pain with disk injury is due to:

Answer 38

1. Pressure on nerve root | 2. Chemical irritation (inflammation --> chemical mediators)

Question 39

Five stages of disk injury

Answer 39

1. Fissure 2. Protrusion 3. Prolapse 4. Extrusion 5. Sequestration (pts usually come in with either fissure or protrusion)

Question 40

Examination of disk injury

Answer 40

1. Mckenzie method of examination (movements to assess) | 2. Identify aggravating activities

Question 41

Treatment of disk injury: cut knuckle analogy

Answer 41

1. Bend a lot: Won't heal quickly - need to modify activities to decrease flexion to decrease recovery time 2. Need some movement (later in healing) to avoid adhesions Establish a directional preference for pt's symptoms -- stay out of that position

Question 42

Treatment of disk injury: Education

Answer 42

Key to success Role of HEP Posture modifications

Question 43

Treatment of disk injury: Extension program

Answer 43

Prone --> Prone on elbows --> Extension in lying (on hands) --> Extension with overpressure (PT holds hips down) **This is if extension helps pt! Disk bulging laterally could feel worse in extension