Alterations in Spinal Cord Function

Anatomy & Physiology of the Spinal Cord

Structure

• CNS = brain + spinal cord

• Spinal cord runs from the medulla oblongata through vertebrae

• Protected by vertebrae and meninges:

  • Pia mater

  • Arachnoid mater

  • Dura mater

• CSF (cerebrospinal fluid) is in the subarachnoid space

Gray vs White Matter

• Gray matter = neuron cell bodies

• White matter = myelinated axons

Main Functions of the Spinal Cord

1. Sends sensory info to brain

2. Sends motor commands from brain

3. Controls reflexes

Ascending vs Descending Tracts

• Ascending tracts = sensory signals → brain

• Descending tracts = motor signals → muscles

Reflex Arc

• Reflexes happen through the spinal cord without brain involvement

• Example: touching something hot → immediate withdrawal

Spinal Nerves & Plexuses

31 Pairs of Spinal Nerves

• Cervical: 8

• Thoracic: 12

• Lumbar: 5

• Sacral: 5

• Coccygeal: 1

Dorsal vs Ventral Roots

• Dorsal/posterior roots = sensory

• Ventral/anterior roots = motor

Plexuses

Cauda Equina

• Bundle of nerve roots at lower spinal cord

• Controls bladder, bowel, legs

Pathophysiology of SCI

Primary Injury

• Direct spinal cord damage

• Causes loss of:

  • Sensation

  • Movement

  • Strength below injury

Secondary Injury

Caused by:

• Inflammation

• Hemorrhage

• Hypoperfusion

• Cellular death

Recovery

• Most recovery = first 3 months

• Can continue up to 18 months

Mechanisms of SCI

1. Compression (most common)

2. Hyperextension

3. Distraction (vertebrae pulled apart)

4. Transection/laceration

SCI Classification

Complete SCI

• No motor or sensory function below injury

Incomplete SCI

• Some movement or sensation remains

ASIA Scale

Injury Levels & Effects

Tetraplegia vs Paraplegia

Tetraplegia (Quadriplegia)

• Injury: C1–T1

• Affects all extremities

Paraplegia

• Injury: T2–S5

• Legs/trunk affected

• Arms intact

Key SCI Complications

Spinal Shock

• Immediate temporary loss of:

  • Reflexes

  • Muscle tone

  • Bowel/bladder function

Neurogenic Shock

Seen with injuries above T6:

• Hypotension

• Bradycardia

• Hypothermia

Autonomic Dysreflexia (AD)

Medical emergency in SCI above T6.

Causes

• Bladder distention

• Fecal impaction

• Pressure ulcers

• UTI

Signs

Above injury:

• Severe hypertension

• Pounding headache

• Flushing

• Sweating

• Bradycardia

Below injury:

• Pale/cool skin

Nursing Actions

1. Sit client upright

2. Lower BP

3. Remove tight clothing

4. Find trigger

5. Empty bladder/bowel

Respiratory Complications

Leading cause of death in SCI:

• Atelectasis

• Pneumonia

Prevention

• Deep breathing

• Coughing

• Suctioning

• Chest physiotherapy

• Incentive spirometry

Venous Thromboembolism (VTE)

Highest risk:

• First 8 weeks after injury

Signs

• Edema

• Redness

• Pain/tenderness

Prevention

• SCDs

• Anticoagulants

• Compression stockings

Skin Breakdown

Most common complication.

Prevention

• Turn frequently

• Log-roll technique

• Remove backboards ASAP

• Pressure-relief mattresses

Bowel & Bladder Problems

Upper Motor Neuron Lesions

• Spastic bowel/bladder

• Leakage

Lower Motor Neuron Lesions

• Flaccid bowel/bladder

• Overdistention

Management

• Intermittent catheterization

• Stool softeners

• Fiber + fluids

• Rectal stimulation

Pain Types in SCI

Pain Treatments

• PT

• ROM exercises

• Massage

• TENS

• Psychological therapy

Emergency SCI Care

ABC Priority

1. Airway

2. Breathing

3. Circulation

Stabilization

• Rigid cervical collar

• Spine board

• Prevent movement

Glasgow Coma Scale (GCS)

Eye Opening

1–4

Verbal Response

1–5

Motor Response

1–6

Total Score

• 3–8 = severe TBI

• 9–12 = moderate

• 13–15 = mild

Halo Fixation Device

Purpose:

• Immobilize cervical spine

Nursing Care

• Pin care daily/every other day

• Watch for infection

• NEVER adjust pins

Rehabilitation

Physical Therapy

• Mobility

• Strength

• Endurance

Occupational Therapy

• ADLs

• Fine motor skills

Recreational Therapy

• Exercise

• Sports

• Social engagement

Sexuality After SCI

• Intimacy still possible

• May need:

  • Lubricants

  • ED medications

  • Alternative stimulation

Important

SCI above T6:

• Monitor for autonomic dysreflexia during sexual activity

Prevention of SCI

Teach:

• Seat belt use

• Helmet use

• Fall prevention

• Water safety

• Avoid distracted/drunk driving

Medications to Know

NCLEX Must-Know Points

• SCI above C4 → ventilator risk

• AD = emergency in injuries above T6

• Highest VTE risk = first 8 weeks

• Respiratory complications = leading cause of death

• Spinal shock = temporary loss of reflexes/function

• Neurogenic shock = hypotension + bradycardia + hypothermia

• Log-roll with cervical stabilization

• Never adjust halo pins

• ABCs are priority in acute SCI

Medication Summaries

Enoxaparin

• Class: Anticoagulant

• Action: Prevents clot formation by increasing antithrombin effects on thrombin and factor Xa

• Use: Prevents thrombus formation

• Key Adverse Effects: Bleeding, thrombocytopenia, anemia

• Important Interactions: Higher bleeding risk with aspirin, NSAIDs, warfarin, clopidogrel

• Contraindications: Heparin-induced thrombocytopenia, pork allergy, hypersensitivity

• Teaching: Report unusual bleeding/bruising; avoid NSAIDs unless approved; learn proper self-injection and sharps disposal

Baclofen

• Class: Antispasticity skeletal muscle relaxant

• Action: Inhibits spinal cord reflexes

• Use: Reduces muscle spasticity and improves bowel/bladder function

• Key Adverse Effects: Drowsiness, dizziness, weakness, hypotension

• Important Interactions: Increased CNS depression with alcohol, opioids, sedatives, antihistamines

• Contraindications: Hypersensitivity

• Teaching: Do not stop abruptly (can cause seizures/spasticity); avoid driving until effects known

Morphine

• Class: Opioid analgesic

• Action: Binds to opioid receptors in CNS

• Use: Pain management

• Key Adverse Effects: Respiratory depression, constipation, hypotension, dependence

• Important Interactions: CNS depressants and alcohol increase sedation/respiratory depression

• Contraindications: Severe asthma, respiratory depression, paralytic ileus

• Teaching: Avoid alcohol/CNS depressants; rise slowly; prevent constipation; monitor for dependence

Venlafaxine

• Class: Antidepressant (SNRI)

• Action: Blocks serotonin and norepinephrine reuptake

• Use: Treats depression and neuropathic pain

• Key Adverse Effects: Suicidal thoughts, serotonin syndrome, insomnia, hypertension

• Important Interactions: MAOIs, serotonergic drugs, alcohol, NSAIDs increase risks

• Contraindications: MAOI use, hypersensitivity

• Teaching: Do not stop abruptly; monitor mood and suicidal thoughts

Docusate sodium

• Class: Stool softener

• Action: Pulls water into stool to soften it

• Use: Relieves constipation

• Key Adverse Effects: Mild cramps, diarrhea

• Contraindications: Acute abdominal pain, nausea/vomiting

• Teaching: Increase fluids/fiber/activity; avoid long-term use

Polyethylene glycol

• Class: Osmotic laxative

• Action: Draws water into GI tract

• Use: Promotes bowel evacuation

• Key Adverse Effects: Bloating, cramping, nausea

• Contraindications: GI obstruction, perforation

• Teaching: May take up to 4 days to work; avoid overuse

Tamsulosin

• Class: Alpha-adrenergic blocker

• Action: Relaxes prostate smooth muscle

• Use: Treats BPH symptoms (urgency, hesitancy, nocturia)

• Key Adverse Effects: Dizziness, orthostatic hypotension

• Important Interactions: Sildenafil and similar drugs increase hypotension risk

• Teaching: Take same time daily; rise slowly; avoid driving if dizzy

Sildenafil

• Class: Erectile dysfunction agent

• Action: Increases nitric oxide effects → vasodilation and erection

• Use: Erectile dysfunction

• Key Adverse Effects: Hypotension, priapism, headache

• Important Interactions: Nitrates can cause life-threatening hypotension

• Contraindications: Nitrate use, pulmonary venous-occlusive disease

• Teaching: Take 1 hour before sex; seek help for erection >4 hr or chest pain

Key MS & SCI Notes

Intrathecal Pain Pump Medications

Correct answers:

• d. Baclofen

• e. Morphine

These medications can be delivered directly into the spinal cord via an intrathecal pump.

Multiple Sclerosis (MS) Summary

What MS Is

• Chronic autoimmune disease causing demyelination in the brain/spinal cord

• Damaged myelin disrupts nerve impulse transmission

Common Manifestations

• Vision problems (diplopia, optic neuritis)

• Muscle weakness/spasticity

• Balance and gait problems

• Fatigue

• Pain

• Cognitive changes

• Bladder/bowel dysfunction

• Heat sensitivity

Types of MS

Question Answer

Client with symptoms that “come and go”:

• a. Relapse remitting MS (RRMS)

MS Risk Factors

Correct answers:

• a. African-American clients

• c. Female clients

• f. White clients of European descent

MS Pain Types

Expected MS Findings

Correct answers:

• a. Diplopia

• c. Sensitivity to heat

• d. Difficulty with balance

PML Manifestations with Natalizumab

Correct answers:

• b. Progressive weakness in arms/legs

• c. Memory loss and difficulty concentrating

• d. Loss of coordination

Urinary Dysfunction Teaching in MS

Correct answer:

• b. Urinate every 1 to 2 hours

High-Yield Nursing Points

Baclofen Safety

• Causes CNS depression

• Avoid alcohol/sedatives

• Never stop abruptly

MS Relapse Criteria

• Symptoms last >24 hr

• Separate from prior relapse by >30 days

• Not caused by infection/fever

Heat Sensitivity in MS

• Avoid overheating

• Use cooling techniques

• Exercise in cool environments/pools

Mobility “4 Ps”

1. Pacing

2. Prioritization

3. Planning

4. Positioning

Fall Prevention

• Assistive devices

• Good lighting

• Remove rugs/clutter

• Proper footwear

Spinal Stenosis

Spinal stenosis is a narrowing of the spaces in the spine that puts pressure on the spinal cord and nerve roots. It commonly affects the cervical (neck) and lumbar (lower back) areas.

Causes

• Aging and degenerative changes

• Herniated or bulging discs

• Osteoarthritis

• Thickened ligaments

• Bone spurs (osteophytes)

• Trauma or previous spinal surgery

• Conditions like rheumatoid arthritis or Paget’s disease

Risk Factors

• Age over 50

• Obesity

• Chronic diseases

• Congenital spinal abnormalities

• Spondylolisthesis (vertebra slipping forward)

Symptoms

• Back or neck pain

• Burning pain

• Numbness or tingling

• Weakness in arms or legs

• Difficulty walking or standing

• Loss of sensation

• Leg cramping

• Increased fall risk

• Relief when leaning forward

Serious Complication: Cauda Equina Syndrome

Compression of nerve roots in the lower spine can cause:

• Paralysis

• Bowel or bladder incontinence

• Sexual dysfunction

• Severe leg weakness

This is a medical emergency and often requires surgery within 48 hours.

Diagnosis

• MRI (most common)

• CT scan

• Nerve conduction/electrodiagnostic studies

Treatment

Most cases begin with nonsurgical treatment:

• NSAIDs or pain medications

• Physical therapy

• Exercise and core strengthening

• Weight management

• Epidural steroid injections

• Activity modification

• Assistive devices or braces

More severe cases may require surgery:

• Laminectomy

• Foraminotomy

• Discectomy with fusion

Degenerative Disc Disease (DDD)

DDD occurs when intervertebral discs lose fluid and elasticity with aging, causing them to dry, crack, flatten, or herniate.

Changes That Occur

• Loss of disc height

• Bulging or herniated discs

• Bone spur formation

• Disc desiccation (drying out)

These changes can place pressure on nerves and the spinal cord.

Symptoms

• Chronic back or neck pain

• Pain worsened by sitting, bending, twisting, or lifting

• Radiating pain into arms or legs

• Numbness and tingling

• Weakness

• Foot drop

• Difficulty walking

• Increased fall risk

Risk Factors & Comorbidities

• Aging

• Genetics

• Smoking

• Hypertension

• Diabetes

• Hypothyroidism

• Peripheral vascular disease

Psychosocial Effects

Clients may experience:

• Depression

• Poor sleep

• Fear of movement

• Reduced quality of life

Diagnosis

• X-rays

• MRI

• CT scan

• Electromyography (EMG)

Treatment

Conservative treatment includes:

• Physical therapy

• Stretching and core exercises

• Heat or cold therapy

• Aerobic exercise

• Proper posture

• Weight control

• Smoking cessation

• Hydration

Surgical options include:

• Lumbar discectomy with fusion

• Disc replacement

• Laminectomy or decompression procedures

Nursing Priorities

Nurses should:

• Assess pain, gait, strength, reflexes, and sensation

• Monitor for bowel/bladder dysfunction

• Watch for signs of cauda equina syndrome

• Educate on exercise, posture, smoking cessation, and weight management

• Promote safety and fall prevention

• Support mobility and coping strategies

Key NCLEX-Style Points

Cauda Equina Syndrome Signs

• Paralysis

• Bowel/bladder incontinence

• Sexual dysfunction

• Severe lower-extremity weakness

Helpful Lifestyle Measures

• Walking

• Swimming

• Core strengthening

• Maintaining hydration

• Weight control

• Smoking cessation

Common Treatments for Spinal Stenosis

• Epidural steroid injections

• Physical therapy

• Laminectomy

• Discectomy and fusion