Lumbar Spine Flashcards
There are 5 lumbar vertebral bodies, which are wider and deeper than any other vertebra. What 2 features do lumbar vertebra lack which are found in either cervical or thoracic vertebrae?
Transverse foramina (found in cervicals)
Costal facets (found in thoracics)
What anatomical feature of lumbar vertebrae is located immediately beneath each vertebra, containing spinal nerve roots, recurrent meningeal nerves, and radicular blood vessels?
Intervertebral neural foramina
Intervertebral neural foramina are narrowed with extension as pedicles glide toward one another. What pathological conditions might cause narrowing of these foramina?
Arthritis Spurs Hypertrophy of posterior longitudinal ligamnet Herniation of nucleus pulposus Tissue congestion/edema Inflammation Perineural edema
How are intervertebral discs named?
Named for vertebra above (e.g. below L2 = 2nd lumbar disc)
Intervertebral discs funciton to dissipate heavy loads. They consist in part of a _____ ____which is the soft mucoid central core, which is surrounded by the ____ _____ made up of concentric lamellae of collagenous fibers
Nucleus pulposus
Annulus fibrosis
Intervertebral discs are thicker anteriorly and thinner posteriorly. Why is this clinically significant?
Discs are more likely to herniate posteriorly
Where do lumbar nerve roots exit in relation to their named vertebrae?
Lumbar nerve roots exit below named vertebra
What nerve plexus provides sensory and motor info to lower extremity?
Lumbosacral plexus
______ = posterior element of lumbar spine that connects other posterior elements to the vertebral body and protects from significant disc herniations of the same vertebra
Pedicles
______ = posterior element of lumbar spine that are lateral projections that lie in the same horizontal plane as the spinous processes
Transverse processes
The inferior facets of lumbar vertebrae face _____, while superior facets face _______
The facets join to form _______ joints with the vertebral units above and below
Laterally; medially
Zygopophyseal
What is the most common lumbar congenital abnormality, occurring in 30% of patients?
Zygapophyseal joint tropism — articular pillars on one side of vertebral unit are twisted so plane of joint does not match that of other side. Assessed with asymmetric muscle tensions and altered spinal motions
What characteristics distinguish spinous processes of lumbar vertebrae from thoracic?
They are thick, quadrangular, and “spade-like” at the ends
The height of the iliac crests corresponds to what lumbar anatomical landmark?
The L4 spinous process
The spinal canal contains the dural tube, spinal cord, and origins of spinal nerves down to approximately ______ or ______ where the spinal cord ends. Below that point is the ______ and ______ of the spinal cord
L1-L2; L2-L3; cauda equina; filum terminalis
The lumbar spine is very mobile and thus predisposed to aches and pain. What are the major motions at the lumbar spine?
Flexion/extension
Sidebending and rotation
T/F: In the lumbar spine, sidebending and rotation are coupled motions (one cannot occur without the other)
True
[can be type 1 or type 2 mechanics]
What are some observations you can make in terms of patient posture while examining the lumbar spine?
Slumped over Erect stance Asymmetry Lumbar lordosis Gait changes
What are some etiologies for slumped over posture while examining the lumbar spine?
Psychiatric considerations — depression Muscle spasm (e.g., psoas) Reactive effort (relief of pressure from condition impinging on lumbar nerves in intervertebral foramen)
What are some etiologies for erect stance posture while examining the lumbar spine?
Protecting herniated disc or effects of spinal stenosis. Especially consider with muscular weakness, reflex changes, or muscle atrophy
How would you evaluate asymmetries while examining the lumbar spine? What are some etiologies for asymmetry?
Evaluate iliac crest heights, greater trochanter heights, asymmetric sacral sulci, and paravertebral muscle humping
Etiologies: short leg syndrome, sacral base unleveling, muscle spasm, scoliosis
What are some gait changes you might note while examining the lumbar spine?
“Listing” of trunk to one side
Antalgic or limping
Foot drop, hiking up hip, rotation of lower extremity
Shuffling or fenestrated gait
Etiologies of gait change: “listing” of trunk to one side
Disc herniation, muscle weakness — especially glut medius
Etiology of gait changes: foot drop, hiking up hip, rotating of lower extremity
Neuromuscular etiologies
Etiology of shuffling or fenestrated gait
Parkinson’s disease
What are some etiologies for tenderness to the spinous processes of lumbar vertebrae?
Fracture, dislocation, underlying infection, arthritis
What are some etiologies of “step-offs” palpated on lumbar spinous processes?
Spondylolisthesis (forward slippage of vertebra which may compress spinal cord)
What are all aspects of your palpation exam of lumbar spine?
Spinous processes for tenderness and/or step-off
SI joint tenderness
Paravertebral muscles for tenderness and/or spasm
Sciatic n. tenderness
Etiologies of SI joint tenderness
Sacroiliitis
Ankylosing spondylitis
Etiologies of paravertebral muscle tenderness and/or spasm in lumbar region
Degenerative/inflammatory MSK abnormalities Overuse injury Poor posture Anxiety Somatic dysfunction
Herniated intervertebral discs, which occur most commonly at ____-____ or _____-_____ may produce tenderness of spinous processes, intervertebral joints, muscles, and/or nerves.
Low back pain may also be referred from the pelvis or abdomen.
L5-S1; L4-L5
Palpation for sciatic nerve tenderness is done in the ____ position with the hip _____
Lateral recumbent; flexed
The sciatic n. is the largest nerve in the body consisting of _____ nerve roots. It lies midway between the _____ and _______ (=sciatic notch)
L4-S3; greater trochanter; ischial tuberosity
Etiologies of sciatic n. tenderness
Herniated disc or mass lesion impinging on contributing nerve roots
It is important to inspect and evaluate overlying skin in lumbar region, as dermatologic conditions/rashes may occur with various conditions including infection, reactive processes, and spondyloarthropathies. What are some examples of skin changes you could see?
Birth marks, port-wine stains, lipomas
Patches of hair (spina bifida)
Cafe-au-lait spots, skin tags, or fibrous tumors (neurofibromatosis)
Normal ROM for lumbar flexion
40-90
Muscles involved in lumbar extension
Deep intrinsic back muscles
Normal ROM of lumbar spine extension
20-45
Muscles involved in lumbar rotation
Abdominal mm.
Intrinsic mm. of back
Normal ROM for lumbar rotation
3-18
Muscles involved in lumbar sidebending
Abdominal mm.
Intrinsic back mm.
Normal ROM for lumbar sidebending
15-30
Describe test, what is positive, what this indicates:
Straight Leg Raise (Lasegue) Test
Patient supine, passively flex pt’s ipsilateral hip with knee extended. Add dorsiflexion to increase dural tension in low lumbar and high sacral levels
+ test = presence or worsening of radicular pain radiating into ipsilateral leg, especially between 30-60 degrees and worse with dorsiflexion
Indicates: lumbosacral radiculopathy (usually from herniated disc) and/or sciatic neuropathy
SLR is considered positive for lumbosacral radiculopathy between 30-60 degrees. What would a positive test mean at greater than 70 degrees vs. pain at around 15 degrees?
Positive signs at >70 is more likely mechanical LBP d/t muscle strain or joint disease
Pain laterally at >15 degrees could indicate IT band contracture
Greater than 95% of disc herniations occur at what region of the spine? Why?
L5-S1 — spine angles sharply posterior
What 2 signs/symptoms make diagnosis of sciatic 5x more likely?
Ipsilateral calf wasting
Weak dorsiflexion
The diagnostic accuracy of the SLR test is limited by its low specificity (but high sensitivity) for dx of radiculopathy due to disc herniation. What additional test can be done to increase specificity?
Contralateral (crossed) SLR test
Describe test, what is positive, what this indicates:
Contralateral (crossed) SLR test
Patient supine, passively flex patient’s contralateral hip with knee extended
+ test = presence or worsening of radicular pain radiating into the contralateral leg, especially between 30-60 degrees
Indicates: lumbosacral radiculopathy (usually from herniated disc) and/or sciatic neruopathy
Describe test, what is positive, what this indicates:
Hoover’s sign
Patient supine. Hold hand under heel of the unaffected leg. Ask pt to try and flex affected (weak) leg against slight resistance while maintaining extension at knee (straight leg). If an honest effort is made, the physician should feel unaffected leg’s heel pushing down as they attempt to raise the affected leg by flexing at the hip
+ test = no downward force of unaffected leg as they are “attempting” to lift affected leg
Indicates: functional weakness (“conversion disorder”) or malingering of the pt
Describe test, what is positive, what this indicates:
Thomas test
Pt supine with buttocks toward end of table. Flex both hips and knees to chest (flattens lumbar lordosis and stabilizes pelvis). Have pt extend affected leg toward table and relax to allow full extension
+ test = lower extremity on involved side will be unable to fully extend at hip
Indicates: iliopsoas tension, shortening, or contracture
T/F: iliopsoas hypertonicity is a common finding in acute and chronic LBP
True
Describe test, what is positive, what this indicates:
Gaenslen test
Patient supine. Flex one hip and knee to chest while simultaneously extending opposite hip (off side of table)
alternative: lateral recumbent; patient flexes lower hip and holds, physician then extends top hip. Maneuver stresses both SI joints
+ test = posterior pelvic pain
Indicates: SI joint dysfunction or pathology
Describe test, what is positive, what this indicates:
Valsalva test
Pt holds breath and bears down which increases intrathecal pressure
+ test = sciatic symptoms (sharp or burning pain radiating down the posterior or lateral aspect of the leg, usually to the foot or ankle)
Indicates: sciatica (sciatic n. compression or irritation), often associated with numbness or tingling
T/F: pain radiating to just above the knee is more likely to represent true radiculopathy than distal leg pain
False; pain radiating below the knee is more likely to represent true radiculopathy than proximal leg pain
Describe test, what is positive, what this indicates:
Stork test
Patient standing. Have patient flex hip and knee of one leg. Stabilize patient’s iliac crests, if needed, and have them lean back extending the lower back
+ test: pain in lower back as it stresses the posterior elements of the spine on the ipsilateral side
Indicates: possible pars defect/stress fracture; if bilateral, increased risk of spondylolisthesis
Condition of spinal nerve root compression usually by massive disc protrusion, fracture/trauma, or tumor that results in bowel/bladder dysfunction
Cauda equina syndrome
There is no single test for cauda equina syndrome, but what are some clinical features that require investivation?
LBP (usually first symptom, present in 83-95% of pts at time of dx; can precede neurologic symptoms by weeks in cases not secondary to immediate trauma)
Bowel/bladder dysfunction (overflow incontinence)
Sensory loss of perineum (“saddle anesthesia”) and decreased anal sphincter tone
Bilateral sciatica and leg weakness
T/F: cauda equina syndrome requires emergent management and surgical decompression within 48 hours, or permanent neurologic damage can remain
True
Congenital malformation (usually failure of lamina fusion in vertebra) leading to neural tube defects (incomplete closure) in lumbar spine
Spina bifida
What type of spina bifida results in a small split in vertebra, with NO spinal cord protrusion, is asymptomatic and usually an incidental finding on radiograph?
Spina bifida occulta
[may also see patch of hair, birthmark, or dimple]
At what spinal segment is spina bifida occulta most common?
L5-S1
What type of spina bifida involves meninges forced out between vertebra and requires surgical repair, usually without any neurological damage
Meningocele
What is the most common type of spina bifida?
Myelomeningocele — unfused portion of spinal cord protrudes through opening. Very severe (permanent) neurologic complications
What is a normal Ferguson’s angle?
30-40
What condition, typically seen on x-ray, appears as a defect or fracture in pars interarticularis of the vertebral arch?
Spondylolysis
What condition, typically seen on lumbar x-ray, appears as an anterior displacement of vertebral body?
Spondylolisthesis
Age-related wear and tear of the spine
Osteoarthritis (spondylosis)
