Back Pain

BACK PAIN

Classification and PathologyBy

Wafer Aldulaimi / Denmark

Introduction

80% of all individuals have experienced back pain in thier life time by the age of 60 years.

Classification of back pain

Pain is differentiated into nociceptive, inflammatory, neuropathic and functional pain.

Functional pain

Functional pain

• No morphological correlate can be found in functional pain.

• Peripheral tissue damage and neural injuries changes in the pain pathways abnormal responsiveness or function of the dorsal root ganglion of the nervous system , as follows:

• Reduction in pain threshold (allodynia) • increased response to noxious stimuli

(hyperalgesia) • increase in the duration of response to brief

stimulation (persistent pain) and a spread of pain .

This phenomenon is called

neuroplasticity

Syndromes which belong to this class of pain are • Fibromyalgia • Irritable bowel syndrome • Non-cardiac chest pain • Tension headache • Whiplash syndrom

NB

• Genetic predisposition and biopsychosocial factors have a significant influence on pain perception .

• Adjuvant drugs (e.g. antidepressants,

anticonvulsants, anxiolytics) enhance the central effect of analgesics and should be included for an adequate treatment of moderate to severe pain .

Anatomy

Causes of pain

1. Spinal degeneration2. Trauma3. Chronic pathological changes4. Spinal deformity5. Inflammatory diseases6. Space occupying and destructive lesions7. Referred pain

Spinal Degeneration

The Intervertebral Disc

start as small tears in the annulus fibrosus

increase in size to form radial fissures extend into the nucleus pulposus loss of proteoglycans and water content from the nucleus loss of the height of the disc disc collapses shortening the distance between the two vertebral bodies vertebral sclerosis + Osteophytes.

The cardinal symptoms of discogenic back pain are :

1) predominant low-back pain . 2) pain aggravation in disc compression and

flexion by forward bending, sitting, coughing, sneezing , walking.

3) non-radicular pain radiation in the anterior thigh ( referred pain)

The facet joint

Begin with an inflammatory synovitis gradual

thinning of the cartilage subperiosteal osteophytes enlarge both the inferior and superior facets.

The cardinal symptoms of facet joint pain are :

1) predominant low-back pain 2) osteoarthritis pain type (morning stiffness , improvement during motion- early stage) 3) pain aggravation in extension and rotation (backward bending ,standing, walking downhill) 4) non-radicular pain radiation in the posterior thigh (referred pain )

Treatment of the degenerative disc and facet joint

Non-operative Treatment The mainstay of non-operative management

rests on three pillars: 1) pain management (medication) 2) functional restoration (physical exercises) 3) cognitive-behavioral therapy (psychological intervention)

Operative Treatment• Non-instrumented Spinal Fusion

• Instrumented Spinal Fusion 1. Pedicle Screw Fixation 2. Translaminar Screw Fixation 3. Cage Augmented Interbody Fusion 4. Total Disc Arthroplasty

TRAUMA

Disc Herniation

Compressive or rotational forces on the spine tear

of the annulus fibrosis the nucleus pulposus may migrate through the tear, causing a protrusion of the disc .

Degenerated discs that already have some degree of

annular tearing, have less elasticity and are less able to withstand these forces.

• If the disc herniation protrudes posteriorly in the midline compression of the cauda equina or spinal cord .

• If the disc protrudes laterally compression on the nerve root .

symptoms

• Radiculopathic symptoms.

• These symptoms must correspond to the respective dermatome and myotome of

the compromised nerve root to allow for a conclusive diagnosis.

Treatment

Conservative Measures for mild radiculopathy 1) Bed rest (< 3 days) 2) Analgesics 3) Anti-inflammatory medication 4) Physiotherapy

Operative Treatment for severe radiculopathy ( Cauda equina syndrom, severe paresis ,etc.)

Standard operations Laminotomy and discectomy

Fractures

With or without neurological symptoms.

Operative and non-operaive treatment.

Chronic Pathological changes

The effects of acute and cumulative trauma

progressive degenerative changes that affect both the intervertebral disc and the posterior facets.

Spinal Stenosis

Degenerative changes significant stenosis of the central canal and lateral foramina disrupt function within the spinal cord and nerve roots.

A pathomorphological changes as:

1) hypertrophy of the ligamentum flavum 2) hypertrophy of the facet joints 3) osteophyte formations 4) disc herniation 5) vertebral displacements (anterior/lateral)

Symptoms are :

pain or numbness in the legs on activity and which is relieved with rest, known as neurogenic claudication.

Treatment

Conservative treatment mild symptoms 1) medication (analgetics, NSAIDs, muscle relaxants) . 2) postural education and therapeutic exercise

with avoidance of extension . 3) epidural infiltration of corticosteroids .

Operative treatment Decompression with or without instrumentation.

MUSCLE TRAUMA, IMMOBILIZATION AND ATROPHY

Pain due to degenerative changes reduces the patients activity atrophy of the paraspinal muscles.

• Muscle atrophy is visible within 3-4 weeks and after 3 months complete muscle atrophy.

• The atrophied muscles is replaced by fibrous collagen.

• Muscle atrophy can cause functional pain.

Normal muscle tissue

After 4 weeks of immobilisation

After 7 weeks immobilisation

After 3 months of immobilisation

SPINAL DEFORMITY

Traumatic, congenital and degenerative changes can all result in deformity of spinal structures.

SPONDYLOLYSIS

• The vertebral arch attaches to the vertebral body through the pedicles. The laminae originate from the pedicle at a comparatively weak area known as the pars interarticularis or isthmus.

• In childhood and adolescence, this area is subject to fatigue fracture, which may not heal properly and can lead to a fibrous union rather than a stable bony union.

• This can happen unilaterally or bilaterally. • If it occurs bilaterally , it creates an area of

weakness between the anterior and posterior components of the vertebral arch.

• If this is stable , it may not be clinically important and can be an incidental finding seen on X-rays and CT scan.

ISTHMIC SPONDYLOLISTHESIS

Bilateral spondylolysis , can separation of the

anterior and posterior elements of the vertebral arch slippage of the superior vertebral body on the inferior vertebral body degenerative changes.

As the spondylolisthesis progresses widening

of the central spinal canal.

DEGENERATIVE SPONDYLOLISTHESIS

During the process of degeneration , there is a

period in which the two adjacent segments are hypermobile slippage narrowing of the central spinal canal

Treatment

• Conservative for mild cases: pain relief , physiotherapy

• Operative for severe cases: spinal fusion (instrumented and non instrumented)

SCOLIOSIS

• Deformity of the normal vertical and/or sagital alignment of spinal segments.

• The causes : congenital , spontaneous and degenerative.

INFLAMMATORY DISEASES

There are a number of systemic diseases that impact on the spine and can result in changes in bony structure, resulting in deformity.

Rheumatoid arthritis

Paget’s disease

Ankylosing spondylitis (Bekhterev's disease)

Space-occupying and destructive lesionsSpinal tumors

Tumors that affect the spine can be primary

benign or malignant .Primary or metastatic tumors spreading from other organs .

SPINAL INFECTIONS

The vertebral column , the intervertebral discs,

the dural sac or the space around the spinal cord may become infected.

The infection may be caused by bacteria or

fungal organisms.

REFERRED PAIN

TAK