**Textbook:** Harrison’s Principles of Internal Medicine (21st Edition)  
**Chapter Number & Name:** Chapter 17 – Back and Neck Pain  
**Topics Covered:**  
- Anatomy of the Spine  
- Classification & Etiologies (e.g., Disk Disease, Stenosis, Spondylosis)  
- Approach to Back & Neck Pain  
- Red Flags & Serious Underlying Causes  
- Diagnosis (Clinical, Imaging, EMG)  
- Treatment: Acute & Chronic Back Pain, Radiculopathy, Surgical & Nonsurgical Options  
**Page Numbers:** 210–235 (Approx.)

Back and Neck Pain

OVERVIEW

Epidemiology & Impact
- Low back pain (LBP) is the #1 cause of disability in adults <45 years old.
- Over 80% of people will experience significant back pain at some point.
- High societal costs due to lost wages and productivity (~$200 billion/year in the U.S.).

SPINAL ANATOMY & PAIN PATHWAYS

Anterior Spine

Vertebral Bodies + Intervertebral Disks:
- Disks = nucleus pulposus (gelatinous) + annulus fibrosus (tough ring).
- Degeneration with age → loss of disk height.
Stabilizing Ligaments: Anterior & posterior longitudinal ligaments.
Pain-Sensitive Structures: periosteum, dura, facet joints, annulus fibrosus, epidural veins/arteries, ligaments.

Posterior Spine

Vertebral Arch: pedicles + lamina → anchor for muscles, ligaments.
Processes: spinous & transverse. Facet joints allow extension, flexion, rotation.

Nerve Roots & Radiculopathy

Exiting Nerve Roots:
- Cervical region: nerve root exits above matching vertebral level.
- Thoracic/lumbar: nerve root exits below vertebral level.
Cauda Equina: below L1–L2. Large disk herniations or mass lesions can compress multiple nerve roots.

🟡 High-Yield: Radiculopathy = nerve root injury → pain or paresthesias following a dermatomal/myotomal distribution, often worsened by coughing, sneezing, straining.

APPROACH TO BACK PAIN

1️⃣ Types of Back Pain

Local Pain: From direct injury to spine structures.
Referred Pain: From abdominal/pelvic organs; unaffected by posture.
Spine-Origin Pain: May radiate to buttocks or lower limbs.
Radicular Pain (Sciatica): Sharp, burning, electric pain along nerve root distribution (L4, L5, S1).
Muscle Spasm: Dull, achy paraspinal pain with abnormal posture.

2️⃣ History & “Red Flags”

Risk Factors for Serious Underlying Cause (Table 17-1):
- Cancer Hx, unexplained weight loss.
- Fever, IV drug use, immunosuppression (infection risk).
- Age >70, trauma, osteoporosis (fracture risk).
- Rapidly progressive neurologic deficits.
- Incontinence or saddle anesthesia (cauda equina syndrome).

3️⃣ Physical Examination

Inspect spine posture (lordosis, kyphosis, scoliosis).
Palpate for tenderness over spinous processes or paraspinal muscles.
Range of Motion: decreased with muscle spasm or pain.
Hip exam: rule out hip joint pathology that mimics LBP.
Straight-Leg Raise (SLR) sign:
- Positive if reproduces patient’s typical radicular pain at <80° leg raise.
- Crossed SLR: SLR of unaffected leg produces pain in affected leg → highly specific for disk herniation.
- Reverse SLR: for L2–L4 root issues.

🔵 Clinical Pearl: “Breakaway weakness” may be due to pain or suboptimal effort; confirm with EMG if uncertain.

4️⃣ Imaging & EMG

No immediate imaging for acute LBP <6 weeks unless red flags present.
MRI or CT myelography → best for serious pathology (tumor, infection) & radiculopathy detail.
EMG/NCS: confirm nerve root or peripheral nerve lesion if exam inconclusive.

🔴 Exam Alert: Spine imaging often reveals incidental degenerative findings in asymptomatic adults → interpret carefully.

COMMON CAUSES OF BACK PAIN

Etiology	Notable Features
Disk Disease	Lumbosacral herniation (L4–L5 or L5–S1) → sciatica, radiculopathy
Degenerative Spine	Osteoarthritic changes → canal stenosis, spondylolisthesis, facet hypertrophy
Spine Infection	Osteomyelitis, epidural abscess → fever, ESR ↑, rest pain
Neoplasm	Constant, dull pain, worse at night; vertebral metastases common
Trauma	Fractures, sprains; suspect if osteoporosis, high-energy accident
Metabolic	Osteoporosis w/ compression fractures, Paget’s disease
Congenital	Scoliosis, spondylolysis, tethered cord
Inflammatory	Ankylosing spondylitis, RA
Referred Pain (viscera)	AAA, pancreatitis, kidney stones, pelvic disease
Postural, Functional	Chronic LBP of unclear origin, possible psychological overlay

Lumbar Disk Disease

Most common in L4–L5, L5–S1. Risk increased by obesity.
Disk Herniation: nucleus pulposus protrudes → radiculopathy or back pain.
Cauda Equina Syndrome: large central herniation → saddle anesthesia, bladder dysfunction, bilateral leg weakness. Surgical emergency.

Spinal Stenosis & Neurogenic Claudication

Narrowed spinal canal → buttock/leg pain triggered by standing/walking, relieved by sitting/flexion.
Often in older adults with degenerative changes.
Tx: conservative (NSAIDs, exercise), decompressive laminectomy if severe.

Neoplastic

Commonly metastatic to vertebral bodies, especially thoracic.
Night pain, unrelieved by rest, progressive.
Urgent MRI for cord compression → emergent steroids, ± radiotherapy or surgery.

Infectious

Osteomyelitis (S. aureus), diskitis, epidural abscess.
ESR/CRP elevated; confirm with MRI.
IV antibiotics, possible surgery if abscess or instability.

Fractures

Compression fractures in osteoporosis or from high-energy trauma.
Pain on palpation, x-ray or CT confirms.
Evaluate for malignancy if suspicious level or risk factors.

Chronic Low Back Pain (CLBP)

No definitive lesion found → posture, muscle imbalance, psychological factors.
Emphasize exercise therapy, self-management, and psychosocial support.

TREATMENT STRATEGIES

Acute Low Back Pain (ALBP)

without

Radiculopathy

Reassure: excellent prognosis, majority improve in 4–6 weeks.
Remain active, avoid prolonged bed rest.
NSAIDs, acetaminophen first-line.
Short-term muscle relaxants or opioids (3–7 days max) if severe.
No routine imaging unless red flags.
Physical therapy, gentle exercise can start early.

🟡 High-Yield: Prolonged bed rest (>2 days) or immediate advanced imaging is not recommended for simple acute LBP without red flags.

Chronic Low Back Pain (CLBP)

without

Radiculopathy

Emphasize long-term exercise programs, core strengthening.
Evaluate and treat depression; CBT may help.
NSAIDs, acetaminophen for pain flares; cautious with opioids.
Injections (facet, epidural) rarely beneficial if no radiculopathy.
Fusion surgery benefit questionable unless spinal instability.

Low Back Pain

with

Radiculopathy (e.g., Sciatica)

Usually due to disk herniation or foraminal stenosis.
Conservative approach for 6–8 weeks if no progressive deficits:
- Activity, NSAIDs, short opioid or steroid taper.
- Epidural steroids can relieve severe radicular pain.
Surgical diskectomy: indicated if:
- Cauda Equina Syndrome or progressive neuro deficit, or
- Severe radicular pain unresponsive to conservative management.
Long-term outcomes similar for surgery vs. conservative therapy; surgery speeds relief.

NECK & SHOULDER PAIN

Cervical Spine

Similar principles as LBP. Focus on spinal cord involvement (myelopathy) and root compression (radiculopathy).
Whiplash: hyperflexion-extension injury → persistent neck pain in up to 50%.
Cervical Disk Herniation: radicular arm pain, possibly from trauma or degenerative changes.
Cervical Spondylosis: osteophytic narrowing → radiculopathy ± myelopathy.
If myelopathy (Lhermitte’s sign, spastic legs) → urgent imaging, possible surgery.

Thoracic Outlet Syndromes

Neurogenic TOS: lower trunk brachial plexus compressed by cervical rib → intrinsic hand muscle atrophy, sensory deficits in C8/T1 distribution.
Arterial/Venous TOS: subclavian vessel compression → vascular insufficiency or thrombosis.

Shoulder Pathologies

Rotator cuff tear, bursitis, tendonitis → pain worsens with abduction, local tenderness.
Referred pain (e.g., subdiaphragmatic irritation, Pancoast tumor) can mimic cervical issues.

FINAL POINTS & PEARLS

Exclude red flags early in back/neck pain evaluation.
Keep imaging selective; many degenerative changes are incidental.
Short-term use of NSAIDs, muscle relaxants, or opioids; encourage activity as tolerated.
For chronic pain, integrate exercise + CBT + address psychosocial factors.
Surgery often not a first-line choice unless severe or progressive deficits, or serious structural issues.

REFERENCES (APA Style, Annotated)

Engstrom, J.W. (2022). Physical and Neurologic Examination. In Steinmetz et al. (Eds.), Benzel’s Spine Surgery (5th ed.). Philadelphia: Elsevier.

— Comprehensive guide on clinical evaluation for spinal disorders.
Cieza, A., et al. (2021). Global estimates of the need for rehabilitation based on the Global Burden of Disease study 2019. Lancet, 396, 2006–2017.

— Quantifies the global prevalence and burden of musculoskeletal disorders, highlighting LBP.
Goldberg, H., et al. (2015). Oral steroids for acute radiculopathy due to a herniated lumbar disk. JAMA, 313(19), 1915–1923.

— Examines efficacy of short-course oral steroids in acute sciatica.
Jarvik, J.G., et al. (2015). Association of early imaging for back pain with clinical outcomes in older adults. JAMA, 313(11), 1143–1153.

— Demonstrates no improved outcomes with immediate imaging in low-risk back pain.
Hara, S., et al. (2022). Effect of spinal cord burst stimulation vs. placebo stimulation on disability in chronic radicular pain post-lumbar surgery: A randomized clinical trial. JAMA, 328, 1506–1516.

— Investigates burst stimulation therapy in persistent radicular back pain.

[▶️ Video Placeholder: “Lumbar Spine Physical Exam & Straight Leg Raise Demonstration (Educational Resource)”]

🔴 Exam Alert: Low back and neck pain are extremely common. Focus on identifying red flags, then employ a conservative management approach for uncomplicated cases. Surgical options mainly for severe neurologic deficits or intractable symptoms.

End of Chapter 17 Summary: Back & Neck Pain