Review of functional anatomy of the spine and clinical correlations

Question 1

What are the most often identified causes for low back pain?

Answer 1

• Intervertebral disc rupture and herniation
• Nerve inflammation or compression
• Degenerative changes in vertebral facet joints
• Sacroiliac joint and ligament involvement
• Metabolic bone disease
• Psychosocial factors
• Abdominal aneurysm
• Metastatic cancer
• Myofascial disorders

Question 2

Symptoms of back pain?

and

Neurologic symptoms related to spinal nerve roots or cord compression?

Answer 2

* Neck, mid-back, low back pain, stiffness and loss of function

* Neurologic symptoms related to spinal nerve root(s) or cord compression:

• Extremity pain
• Numbness
• Tingling
• Weakness
• Bowel/bladder urgency/incontinence

Question 3

Components of musculoskeletal spine examination?

Answer 3

1. Inspection/observation
2. Palpation
3. Range of motion
4. Neuromuscular examination
5. Special tests
6. Examination of related areas

Question 4

14 yo girl with flaccid paralysis limited to right arm. No pain, paresthesias, sensory loss noted. Laboratory results reveal polio virus infection. Identify the target.

and WHY

Answer 4

Ventral horn of the spinal cord gray matter

NOT

Dorsal rami of spinal nerves

Dorsal rami of spinal nerves

Ventral rami of spinal nerves

Only the ventral horn (and also ventral root) are motor. Dorsal root is sensory. All rami are mixed.

Question 5

What is a myotome?

What is a dermatome?

Answer 5

A myotome: is a collection of muscle fibers innervated by the motor axons within each segmental nerve (root)

A dermatome: is an area of skin innervated by the sensory axons within each segmental nerve (root)

Question 6

For dermatomes…

What types of cells?

Where do they reside?

How many pairs?

What is the top of the head dermatome?

What about the face?

Answer 6

Pseudounipolar cells

With their cell bodies residing in Dorsal Root Ganglions

31 pairs of spinal nerves

C2 innervates the top of the head because C1 contributes little to skin

Over the anterolateral head the skin is innervated by one of the three divisions of the trigeminal cranial nerve.

Question 7

What is shingles/herpes zoster?

Answer 7

Shingles or Herpes Zoster

Is the most common infection of the peripheral nervous system.

Is an acute neuralgia confined to teh dermatome distribution of a specific spinal or cranial sensory nerve root.

Question 8

What is the manual muscle testing scale?

Answer 8

5-Examiner cannot overcome

4-Examiner can overcome

3-No resistance

2-No gravity

1- Flicker or trace of contraction but no joint motion

0-No contraction palpated

Question 9

Thoracic spine manual muscle testing.

Answer 9

C5- Biceps-Elbow flexor

C6-Extensor carpi radialis-Wrist extensor

C7-Triceps-Elbow extensor

C8-Flexor digitorum profundus (3rd)-Distal finger flexor

T1-Abductor digiti minimi-little finger abduction

Question 10

Causes of muscle weakness?

Answer 10

Muscle strain

Pain/reflex inhibition

Peripheral nerve injury

Nerve root lesion (myotome)

Upper motor neuron lesion

Tendon Pathology

Avulsion

Psychologic overlay

Question 11

Lumbar spine exam manual muscle testing

Answer 11

L2-Iliopsoas-Hip flexor

L3-Quadriceps-Knee extensor

L4-Tibialis anterior-Ankle dorsiflexor

L5-Extensor hallicus longus-Big toe extensor

S1-Gastrocnemius-Ankle plantarflexor

Question 12

Reflex testing scale

Answer 12

Grading MSR: NINDS scale

0-absent

1-slight or less than normal (trace response or response only broughtout with reinforcement)

2-Lower half of normal (low-normal)

3-Upper half of normal (high-normal)

4- Enhanced and more than normal (inclu. clonus)

Question 13

Cervical spine reflex testing

Answer 13

C5-Biceps

C6-Brachioradialis

C7-Triceps

Question 14

Lumbar spine reflex testing

Answer 14

L4-Quadriceps (patellar)

L5-Medial hamstring

S1-Gastrocnemius (Achilles)

Question 15

What are the special tests of the cervical and lumbar spine?

Answer 15

Cervical

Lhermitte’s sign

Spurling’s Neck Compression test

Hoffmann’s sign

Lumbar

Straight-leg raising test (SLR or Lasegue sign)

Femoral nerve stretch test (upper lumbar disc)

Question 16

What is Lhermitte’s sign?

Answer 16

Passive anterior cervical flexion elicits electric-like sensation down spine or extremities, implying CERVICAL SPINAL CORD PATHOLOGY

Question 17

What is Spurling’s Neck Compression test?

Answer 17

Reproduction of radicular symptoms with cervical spine extension, rotation, and lateral flexion.

Implies CERVICAL NERVE ROOT PATHOLOGY

Question 18

What is Hoffmann’s sign?

Answer 18

Flick the patient’s middle finger (passive snapping flexion of middle finger distal phalanx)

Positive test is flexion-adduction of ipsilateral thumb and index finger.

Implies UPPER MOTOR NEURON PROCESS AFFECTING CERVICAL SPINE OR BRAIN

Question 19

What is the Straight-leg raising test (SLR or Lasegue sign)?

Answer 19

Patient lies supine while leg raised with knee extended. Examiner stops raising leg when patient reports pain.

Positive test is leg pain reproduced at 30-70 degrees angle.

Implies LUMBAR NERVE ROOT PATHOLOGY (L5 or S1)

Question 20

What is the Femoral nerve stretch test (upper lumbar disc)?

Answer 20

Patient placed in prone position while knee is flexed.

Positive test is reproduction of patient’s pain in anterior thigh

Implies UPPER LUMBAR NERVE ROOT PATHOLOGY (L2-L4)

Question 21

What would make you think of an UMN injury?

(Spinal cord injury, Brain injury/stroke, Myelopathy, CNS lesion)

Answer 21

Spasticity/hypertonicity

Increased reflexes (hyperreflexia)

Positive pathological reflexes

Extensor plantar response

Question 22

What should make you think of a lower motor neuron injury? Begins with the anterior horn cells of the spinal cord and includes the peripheral nerves

(Peripheral nerve entrapment, radiculopathy)

Answer 22

1. Flaccid weakness
2. Loss of reflexes (hyporeflexia)
3. Muscle wasting and atrophy

Question 23

Red flags for identifying serious conditions like malignancy

Answer 23

1. History of cancer
2. Unexplained weight loss
3. Age>50

Question 24

Red flags for identifying serious conditions like spinal fracture

Answer 24

1. Major trauma
2. Minor trauma or strenous lifting in older/osteoporotic individuals
3. Prolonged corticosteroid use
4. Osteoporosis
5. Adv age > 70

Question 25

Red flags for identifying serious conditions like infection

Answer 25

1. Constitutional symptoms (fever, chills) 2. Recent bacterial infection (urinary tract or skin infections, pneumonia) 3. Immunosuppression 4. Intravenous drug abuse.

Question 26

For lumbar strains, What is the history? What is the etiology? What is found on exam? What is treatment?

Answer 26

_Lumbar strain_ **History**: Axial low back pain after acute injury like lifting or twisting;pain worse with movement;better with rest **Etiology**: Muscle disruption from excessive stretch or tension **Exam**: localized muscle tenderness/reduced ROM/Normal neuro exam **Treatment**: Relative rest Pain control with NSAIDS, muscle relaxants Physical therapy if \>4 weeks or recurring Majority self limited

Question 27

Radiculopathy, nerve root impingement What are the most affected nerves in cervical spine and lumbar spine?

Answer 27

Cervical spine: C6, C7 most affected Lumbar spine: L5, S1 most affected

Question 28

What are the pathophysiologies of radiculopathy?

Answer 28

**Mechanical compression of nerve root** - Neural ischemia, increased intraneural pressure - Edema of nerve root, DRG - Dura is mechanically sensitive **Biochemical irritation of nerve root** - Nucleus pulposis contains cytokines, leukotrienes, cox2,interleukin1, tnf-alpha - Can cause apoptosis of DRG cells

Question 29

For Disc Herniations, what is the history?

Answer 29

Acute injury/event or more insidious. Limb pain\>axial spien pain numbness/tingling/weakness may or may not be present Worse: lumbar- sitting, bending, cough/sneeze Cervical- ROM Better: lumbar- standing, walking Cervical-lying

Question 30

What are exam findings for disc herniations?

Answer 30

Myotomal weakness Dermatomal pain/numbness/tingling Decreased or absent reflex of affected nerve Spurling or SLR positive

Question 31

What are the typical treatments for disc herniation?

Answer 31

Activity modification-avoiding bedrest Pain medication: NSAIDs, neuromodulators, short course oral prednisone, limited opioids Physical therapy Epidural steroid injection for pain control \*Surgical discectomy possible but 70-85% improve w/out

Question 32

What indications are there for discectomies in disc herniations?

Answer 32

Progressive or profound weakness Refractory symptoms Bowel/blader dysfunction Myelopathy

Question 33

What is Ankylosing Spondylitis presentation early and late?

Answer 33

Early Ankylosing Spondylitis: - Widening of the sacroiliac joints with adjacent sclerosis compatible with sacroilitis - There is posterior longitudinal ligament sclerosis at L1-L2, L2-L3 Late Ankylosing Spondylitis: - Fusion of both sacroiliac joints compatible with advanced sacroilitis - Symmetric syndesmophytes bridging all vertebral bodies resulting in a bamboo spine - Ossification of the anterior, posterior, and interspinous longitudinal ligaments

Question 34

What is Ankylosing spondylitis?

Answer 34

A chronic inflammatory disease with progressive involvement of sacroilac and axial skeletal joints. Also w/ enthesitis as well as chondritis and osteitis

Question 35

For Ankylosing Spondylitis - Systemic effects? - History? - Exam? - Labs? - Treatment?

Answer 35

**Systemic effects** Upper lobe interstitial lung fibrosis Iritis CV abnormalities (aortitis, aortic insuff, cardiomegaly, conduction defects) **History** Slowly progressive low back pain and stiffness. Worse in morning and with prolonged inactivity, better with exercise. Exam Reduced lumbar ROM, tender over SI joints, SI joint provocative tests positive. otherwise unremarkable **Labs** Elevated C-reactive protein, sedimentation rate. 90% HLA-B27 positive **Treatment**: NSAIDs/Physical therapy/Anti-TNF-alpha agents if severe and refractory to NSAIDs

Question 36

What is spondylolysis and spondylolisthesis

Answer 36

Fracture of PARS lamina with no slippage of adj articulating vertebrae (most common L5-S1) versus bilateral defect with complete dislocation w/anterior displacement of the L5 body and transverse process.

Question 37

What is the **History** **Etiology** **Exam** **Treatment** For _Facet joint arthropathy_

Answer 37

For _Facet joint arthropathy_ **History**: Axial low back pain, gradual onset. Cervical worse with cervical extension, lumbar worse with standing/walking (better sitting/lying) **Etiology**: Gradual degen/osteoarthritis to zygoapophyseal (facet) joints. These are synovial joints and this becomes common \>55 **Exam**: Nonspecific, pain provoked with active extension, relieved with flexion **Treatment**: Imaging, NSAIDs, Physical therapy, Facet joint steroid injections if refractory

Question 38

For **_Lumbar stenosis_** History Exam Etiology Treatment

Answer 38

**History**: Slowly progressive pain in back and uni or bilateral legs (worse when standing/walking, relieved with lumbar flexion, sitting)\> Usually \>55 yo **Exam**: No focal findings, neural exam normal **Etiology**: Narrowing of the spinal canal **Treatment**: Physical therapy, gait aid, NSAIDs, Epidural steroids, Surgical if intolerable pain

Question 39

What is the most common cause for compression fractures?

Answer 39

Osteoporosis Assoc. with prolonged coritcosteroid use. However if \<55 yrs then consider underlying malignancy such as multiple myeloma.

Question 40

For **_compression fractures_** History Exam Labs Treatment

Answer 40

History: Sudden onset of thoracic or lumbar pain Can be related to trauma/fall/heavy exertion, or not. Worse with flexion and movement Better with rest. Usually no leg pain or tenderness. Exam: Local tenderness, painful lumbar ROM (especially flexion), normal neuro Treatment Imaging: plain xrays or maybe MRI or CT If malignancy suspected: CBC, SPEP, alkphos, ESR NSAIDs, acetaminophen, calcitonin, mild opioids Bracing x6 weeks Osteoporosis workup (DEXA scan, endocrine w/u)

Question 41

For **_Caudal Equina Syndrome_** History Etiology Exam Treatment

Answer 41

For Caudal Equina Syndrome **History**: Back pain Leg pain (numbness, weakness) Saddle anesthesia Bowel or bladder dysfunction (urinary retention most common) **Etiology**: Large herniated disc compressing cauda equina most common (can also be epidural tumor/abcess/hematoma) **Exam**: Reduced or absent reflexes, weakness, decreased rectal tone **Treatment**: Surgical emergency

Question 42

Findings from exam for Cervical Myelopathy

Answer 42

- UE and LE w/ predom upper motor neuron findings and weakness below level of cord involvement (Hyperreflexia in upper and lower limbs, Hoffman's sign/positive babinski, ankle clonus) - Lhermitte sign - Romberg sign - Wide base, ataxic, shuffling, slow gait

Question 43

Etiology for Cervical myelopathy

Answer 43

Spinal cord compression Usually gradual progression due to posterior osteophyte formation, spinal stenosis (can also occur due to tumor, abcess, hematoma, and other cord compressive lesions)

Question 44

Treatment for Cervical Myelopathy

Answer 44

Surgical treatment for cervical decompression (laminectomy), may not correct neuro deficits but will prevent progression.