1. Degenerative Spine Diseases
A Class for Foreign MD Students
Degenerative Spine Diseases
Dr. Yue Wang
王 跃 MD, PhD
Department of Orthopedic Surgery
The First Affiliated Hospital, college of Medicine, ZheJiang University
浙江大学医学院附属第一医院骨科

2. Contents Anatomy of the Intervertebral Disc
Overview of Spine Degeneration
Lumbar Disc Herniation
Cervical Spondylosis
Lumbar Spinal Stenosis

3. Anatomy of the intervertebral disc
Two major components
Annulus fibrosis: thick, fibrous “radial tire” called lamellae
Nucleus pulposus: ball-like gel

4. The disc

5. The disc The disc is the largest avascular organ in the human body!
Take about 80% loads in the spine!

6. Spine Degeneration
A process involving structural changes of affected joints and intervertebral disc, with thickening of joint capsule, ligaments, appositional bone formation in response to long term mechanical forces.
Epidemiology
Very common: By age 50, 95% of people show radiographic evidence of lumbar disc degeneration. Yet, only a small portion of them have symptoms.
In other words, fractures mean break down of the bone in two or more parts.

7. Degenerative changes of the disc
Pathological changes
Water and proteoglycan content decreases
Collagen fibers of AF become distorted
Tears may occur in the lamellae
Results in:
Decreased disc height and volume
Decreased resistance to loads
In other words, fractures mean break down of the bone in two or more parts.

8. Risk factors Increasing age; Heredity plays an important role;
Twin studies revealing similar incidence despite different occupations, socioeconomic status
Smoking;
Occupation/leisure activity likely does not play a major role;
Body habitus;

9. Pathophysiology Decreased water content in nucleus pulposus
Causes loss of disc height, causing facet joints to override each other;
Facet joints respond with hypertrophy and osteophyte formation;
Can lead to compression of neurological structures, and/or to abnormal movement which worsens the cycle;

10. Degenerative changes of the vertebral body
Sclerosis: Increased bone formation at the endplates
Reduced nutrition supply
Reduced ability to absorb loads
Osteophytes: Formation of small bony spurs

11. Degenerative changes of the facet joint
Cartilage lining loses water content
Cartilage wears away
Facets override each other
Leads to abnormal function of motion segment

12. Degenerative changes of the ligaments
Partial ruptures, necrosis and calcifications
Negatively impact function of motion segment

13. Clinical implications
Axial pain – neck or back
Due to inflammation surrounding diseased structures or to instability of the spine
Neurologic compression
Compresses laterally to nerve root
Radiculopathy
Compresses centrally in canal
In cervical spine: myelopathy
In lumbar spine: neurogenic claudication or cauda equina syndrome
indirect violence such as falling on a hand or foot , fractures on the spine and hip. armwrestling

14. Back pain 80% adults will have episode back pain;
Most improve over time, therefore initial rest period (short) followed by early mobilization, PT, NSAIDS, lifestyle modification is the treatment;
fractures were caused by a sudden powerful contraction of the attached muscle. Often see in kids and athletes. Common sites are the tibia, calcaneal and anterior inferior iliac spine
90% are not associated with specific discernable cause! (Idiopathic back pain);

15. Back pain
Red flags (fevers, night sweats, neurological symptoms, weight loss, cancer), severe pain not improving warrant further imaging.
Guidelines published on when to image, types of conservative treatment
Xray, MRI

16. Radiculopathy Arm pain; leg pain, sciatica;
Due to compression lateral to the spinal cord in cervical spine, distal or lateral to nerver root/cauda equina in lumbar spine;
Thoracic radiculopathy rare
Most common is C5/6, then C6/7;
In L spine most common is L5/S1 then L4/5;

17. Radiculopathy – clinical
Pain is the most prominent, along dermatome of affected root;

18. Lumbar disc herniation
With disruption of the anulus, the soft nucleus was pushed through (herniated) the annulus.
Herniation occurs through a tear in the anulus fibrosus.
Most common at L4/5 and L5/S1 levels, and then L3/4 level;
Herniated disc at upper L spine is rare.

19. Pathoanatomy Paracentral herniation is most common;
Paracentral herniation tends to affect nerve root of one level lower!
L3/4 DH: affects L4 root;
L4/5 DH: affects L5 root;
L5/S1 DH: affects S1 root;
fractures were caused by a sudden powerful contraction of the attached muscle. Often see in kids and athletes. Common sites are the tibia, calcaneal and anterior inferior iliac spine

20. LDH and Sciatica
The most classic symptom of a herniated disc is radicular pain in the lower extremity following a dermatomal distribution: sciatica.
Mechanical compression;
Neuroischemia-->inflammation;
Neurochemical factors: immune response
Focal neurologic deficits;

21. LDH and back pain
Most patients with symptomatic disc herniations present with leg and back pain.
The disc is almost aneural, so where is the pain from?
Mechanical alternation? Innervation of a long degenerated disc? Biochemical irritation?
Occur as a result of disease such as carcinoma, osteogenesis imperfecta, Pager’s disease and infection.

22. Classification of LDH
Extruded
Sequestered
Protrusions

23. History and symptoms long-standing mild to moderate back pain;
May have a specific incident attributable to the onset of leg and back pain;
Axial back pain is typically present;
Buttock pain: can be referred or radicular in nature
Radicular pain is more typical and often the more “treatable” of the complaints;

24. Patterns of radiculopathy
S1 radicular pain may radiate to the back of the calf or the lateral aspect or sole of the foot;
L5 radicular pain can lead to symptoms on the dorsum of the foot;
L4 radiculopathy: above or below the knee;
L2 and L3 radiculopathy can produce anterior or medial thigh and groin pain

25. Physical Examinations
Inspection:
Abnormal gait: limping, slapping; footdrop;
Alignment of the spine Extension: loss of lumbar lordosis, scoliosis;
Palpation and Percussion:
Tenderness at multiple levels;
Local percussion;
Paraspinal muscle spasm;

26. Neurologic Examination (1)
Sensation: (normal, diminished, or absent )
L4 sensory function is tested at the medial ankle;
L5 at the first webspace between the great and second toes;
S1 at the lateral aspect of the sole of the foot;

27. Neurologic Examination (2)
Motor examination
L4 involvement most often affects ankle dorsiflexion (anterior tibialis);
L5 is tested by toe dorsiflexion, particularly the great toe (extensor hallucis longus), and hip abduction.
S1 motor function is assessed by testing plantar flexion;

28. Manual muscle test (MMT)

29. Neurologic Examination (3)
Deep tendon reflexes
The patellar tendon reflex may be diminished or absent with L3 or L4 involvement;
The Achilles tendon reflex is affected primarily by S1;
There is no specific reflex that reliably reflects L5 function.

30. Specific tests
Straight leg raising test (SLT): reproduce sciatica at degrees; (for L4, L5 & S1 radiculopathy);
Lasègue maneuver;
The femoral stretch test: reproduce anterior thigh pain (for upper root pathology);

31. Imaging
X-ray: show spinal degenerative changes but not a herniated disc; rule out obvious underlying problems;
CT: relatively less used;
MRI: The best;

32. MRI

33. Axial images

34. Differential diagnosis
The differential diagnosis should be narrowed based on history, physical examination, and selected imaging tests.
idiopathic low back pain; sprain or strain;
spinal stenosis;
Abscess; tuberculosis;
Tumor;
Intrinsic nerve problems;
This type of fracture is caused by repeated minor trauma as in training of athletes. ISTRESS # “This type of fracture is caused by repeated minor trauma as in training of athletes. In this small cracks appear in the bone

35. Nonoperative Treatment
Physiotherapy: Bed rest should be limited to no more than 2 to 3 days; restore strength, flexibility, and function;
Pharmacologic Treatment: Nonsteroidal anti-inflammatory drugs (NSAIDs) are first-line agents; muscle relaxants;
Selective transforaminal steroid injections;

36. Natural History
A benign disease: Saal and Saal a 90% good or excellent outcome in patients treated nonoperatively;
Another study: at 1 year, 33% had good results, 49% had a fair result, and 18% had a poor result. At 4 years, good results were reported in 51%, fair results were reported in 39%, and poor or bad results were reported in 10%.
10-year follow-up results: 61% improvement in the predominant symptom, 40% resolution of low back symptoms, and 56% satisfaction rate.

37. Operative Treatment Indications progressive neurologic deficit;
cauda equina syndrome;
failure of appropriate nonoperative treatment;

38. Discectomy Release ligamentum Inspect neural foramen Resect lamina
Remove disc tissues

39. Cervical spondylosis Cervical discs similar to lumbar discs, but:
Nucleus pulpous smaller
Discs better supported on lateral margins
Most cervical disc herniations occur in postero-lateral margins

40. Cervical disc herniation
Patients usually present with one or more of:
Axial neck pain
Radicular arm pain
Myelopathy
Neurapraxia of upper extremities
Non-specific symptoms: dizzying, nausea, head ache, upper back pain;

41. Treatment of radiculopathy
Nonoperative Treatment
Cervical radiculopathy often resolves without surgery
Conservative methods include PT and anti-inflammatory medicines
Indications for surgery
Continued pain or progressive neurological deficit indicate need for surgery
Anterior and posterior approaches may be used
Fusion with or without instrumentation may be done

42. Typical surgery: ACDF
Anterior cervical decompression and fusion (ACDF);
Anterior discectomy;
Bone graft or cage;
Instrumentation;

43. Myelopathy (1)
A group of symptoms resulting from spinal cord compression, including:
Hand dysfunction
Distal often more affected
Difficulty with buttons, handwriting
Otherwise, extensor pattern ‘pyramidal pattern’
Triceps, wrist extension
Leg dysfunction
Balance difficulty
Staggering gait
Tandem gait difficulty very early finding

44. Myelopathy (2) Sensory disturbance
Often bilateral hand difficulty, sensory level as disease is more severeait
Upper motor neuron signs
Babinski response, hyperreflexia, Hoffman’s sign, increased tone, stiff gait

45. Degenerative myelopathy – natural history
Typically that of worsening;
Stepwise in 50%, progressive in 50%;
Therefore, patients with myelopathy are usually treated surgically;
Surgery typically performed in expedited fashion;
Relative to rate of deterioration
Lost neurological function is often not regained – the reason to perform early surgery
There are a lot of ways to describe the fractures, though the Terms used to describe each are related.

46. Surgery
Laminaplasty
Laminectomy

47. Cervical spondylosis

48. After decompression

49. Lumbar spine stenosis (LSS)
A narrowing of the spinal canal;
one of the most common conditions in the elderly;
Can occur in asymptomatic individuals: Radiographic stenosis is common;
in adults older than 65, LSS is the most common reason to undergo lumbar spine surgery;

50. Three shapes of the spinal canal
The narrowed canal

51. Classification Central stenosis; Lateral recess stenosis;
Foramen stenosis;

52. Clinical presentation
Most commonly present with leg pain: neurogenic claudication or radicular leg pain;
Low back pain, common;
This type indicates that there is no communication between the external surface of the body and the fracture. Fracture with intact overlying skin
Bowel and bladder incontinence, uncommon;

53. Neurogenic claudication
Spinal stenosis compressing central lumbar spine below level of spinal cord may cause neurogenic claudication;
Walking induced leg symptoms of heaviness, numbness, pain, cramping, burning or weakness;
Leaning forward posture while walking; (why?)
Relieved by sitting;
Differential diagnosis
Peripheral neuropathy
Stocking pattern, diabetes
vascular claudication
Look for nail changes, hair loss, pulses on feet
Typically occurs in older age groups (>65yrs)

54. Imaging: X-ray

55. Imaging: CT

56. Imaging: MRI

57. Treatment
Rarely progresses to severe deficits, is more of a pain syndrome
initial treatment is conservative
Weight loss, smoking cessation, physiotherapy
Decompressive surgery considered:
if trial of 3 months conservative therapy fails, AND disability is bad enough that patient wishes to consider surgery, AND patient factors (medical comorbidities) are such that surgery can be performed

58. Operative treatment: laminectomy

59. The Rock Mountain, 2012