Lumbar Anatomy Flashcards
1
Q
Features of a Lumbar Vertebrae
A
- LARGE KIDNEY-SHAPED BODY
- SHORT, FLAT, RECTANGULAR SPINOUS PROCESS
- ARCH IS VERY THICK
- LONG TRANSVERSE PROCESSES
- SMALL TRIANGULAR VERTEBRAL FORAMEN
- ARTICULAR PROCESSES FACE M/L
2
Q
Bony elements- 3 zones in the vertical sagittal plane
A
- Vertebral Body
- Pedicles, neural foramen
- Posterior Arch
3
Q
Vertebral Body
A
- Function:
- Weight bearing
- Cortical bone
- Cancellous (trabecular) bone
- Up to 50% of compressive load to the body is borne by the trabecular bone, 50%by the cortical shell
- Blood supply helps trabecular bone and shell manage compressive loads
- Endplates Molecules for nutrition of the disc are extruded through the end-plates with compressive loading
- Blood within the vertebral body increases the load bearing capacity
- Weight bearing
4
Q
Posterior Elements/Arch
A
- Connected to the body by the Pedicles
- Laminae
- Transverse processes
- Articular processes
- Body, pedicles, and posterior arch form the vertebral canal
- Intervertebral foramen between pedicles
5
Q
Function of the posterior arch
A
- Attachment sites for ligaments and muscles
- Osseous ring to protect neural tissue
6
Q
Lumbar Spine Joints
A
- 3 joint complex: 1 anterior (interbody) and 2 posterior (facet joints)
- Facet joints = Zygapophyseal joints
- Facet joints are part of the posterior arch
- Only facet joints are synovial
- Facet Joints
- 52 including upper cervical spine (not including ribs)
- 10 in the lumbar region
- Plane synovial joints
- Synovial tags, menisci
7
Q
Lumbar “FACET” Joints
A
- Synovial joints
- 2 inferior and 2 superior
- Superior joint surfaces face posterior (medial)
- Inferior surfaces face anterior (lateral)
- Innervated from a minimum of 3 nerve root levels (thus pain referral is varied, and not diagnostic)
- Different shapes have been noted
8
Q
Weight bearing in the lumbar region
A
- While the facets take on load…
- The inter-body joint is the principle weight-bearing component of the lumbar spine unless extreme lordosis or other anomaly
9
Q
Facet Joint Movement
A
- During erect sitting the facet joints have been found to carry no vertical load (no lordosis)
- End range extension, the tips of the inferior process of the superior vertebra impact on the lamina of the inferior vertebra - loads are transferred to the lamina
- Prolonged standing with a lordotic spine, the facet joints become impacted
- Load sharing with lordosis:
- L1 - L2/3 = 11%
- L3 - L5/S1 = 19%
10
Q
Facet Joint Loading
A
- Loading depends upon the tilt of the vertebra
- Narrowing of the intervertebral disc space can result in 70% of the axial load being borne by the facet joints
- Leads to degenerative changes in the facet joint
- Highest loading in the extended position
- Axial loading of the lordotic spine = accentuated lordosis, strain on the anterior ligaments which now share the load bearing
11
Q
Arthritis of the Vertebrae
A
- Osteoarthritis can cause bony growths (osteophytes) to form on the vertebrae. These can limit motion and cause pressure on the spinal nerves as they travel through the intervertebral foramina.
12
Q
Lumbar Facet Capsule
A
- Facet capsule
- Contains a meniscoid / meniscus and is highly Innervated
13
Q
Lumbar Facet Joint Pain Maps- Posterior
A
14
Q
Lumbar Facet Joint Pain Maps- Anterior
A
15
Q
Issue at hand with Lumbar Spine
A
- Any innervated structure in the lumbar region can be and is a source for pain (ligament, bone, tendon, joint capsule, insertion point, disc, etc.)
- There are no diagnostic tests that have great sensitivity or specificity for a structure as the source of pain
- Diagnostic injections are most likely the best tool to date, but by no means are they perfect
- Recognize that the facet joint can be the source of nociception that leads to perception of pain in the LE, even past the knee
17
Q
Motions of the Lumbar Vertebrae
A
20
Q
SIJ and Pelvic Girdle Pain Patterns
A
