Understanding Back Pain

• Back pain is a common and important health issue, divided into neck, upper, lower, or tailbone pain.
• Low back pain is defined as pain at the midline between the costal margin and the inferior gluteal fold, and should be differentiated from groin and gluteal pain.
• The lifetime prevalence of back pain ranges from 40-60% in the general population, and most cases are self-limiting; 5-10% of patients develop recurrent symptoms.
• Peak incidence of back pain occurs between 40-60 years old.
• There is no difference in back pain incidence between males and females, but it is more common in heavy, manual occupations and in smokers.
• Numerous pain receptors are located in the lumbar spine region, mostly at the annulus fibrosis and facet joint, supplied by the dorsal spinal nerve root.
• The cauda equina and spinal nerve roots at the segmental spinal level are in close proximity, subject to irritation, and may produce neuropathic pain.
• Understanding of back pain remains limited.
• About 50% of specific low back pain cases are due to a prolapsed intervertebral disc.
• Other diagnoses include spondylolisthesis, spinal stenosis, failed back surgery syndrome, primary or secondary tumor, fracture, or inflammatory disease.
• An exact pathoanatomical association often cannot be identified, and the causes may be multifactorial, including psychological and social factors.
• If no distinct pathology can be identified, the pain is categorised as non-specific low back pain.
• Causes of back pain can be mechanical, psychological, or non-mechanical, including inflammation, infection, or tumors.
• A mechanical problem is defined by issues with spine movement or feeling when the spine moves in certain ways.
• Intervertebral disk degeneration is the most common mechanical cause of back pain, and is defined by disks between vertebrae of the spine breaking down with age.
• Presentation can be simple musculoskeletal pain (95%), spinal nerve root pain (4-5%), or serious spinal pathology (~1%).
• Causes can be musculoskeletal, degenerative, rheumatic, neoplastic, referred, infection, psychological, or metabolic.

Musculoskeletal Causes

• Musculoskeletal causes include ligamentous, muscular, facet joint, sacroiliac strain, prolapsed disc, fracture and scoliosis issues.
• These musculoskeletal issues are mechanical in nature and can occur between ages 20-55.
• They can cause pain in the lumbosacral area and buttocks, referred into upper thighs.
• This pain can be a dull ache that varies with activity.
• Muscle tension occurs due to over-stretched or torn muscles, resulting in damage to the muscle fibers.
• Spine injuries, such as sprains and fractures, can cause either short-lived or chronic pain.
• Fractured vertebrae are often the result of osteoporosis, and less commonly, accidents or falls.
• Facet joint dysfunction has been described as a cause of back pain.
• Diagnosis is based on the clinical presentation of mechanical back pain, which worsens with extension and with radiological features of facet joint arthritis.
• Specificity of the diagnosis for facet joint dysfunction is increased by diagnostic anaesthetic injection.
• Sacroiliac strain can be a cause of musculoskeletal back pain.

Prolapsed Disc

• This generates shooting pain radiating down the leg, below the knee, and is aggravated by coughing/sneezing.
• It generally has a sudden onset, with no trauma.
• This is a well-recognised form of back and leg pain due to radiculopathy.
• The nucleus pulposus from the intervertebral disc escapes from its normal anatomical confines, irritating the adjacent nerve root, causing typical radiculopathy pain.
• Type of herniation can be defined by its relationship with the annulus and the posterior longitudinal ligament.
• A contained bulging disc occurs when the nucleus pulposus still has not pushed through the annulus.
• An extruded disc is when the nucleus has pushed through the annulus, but is still connected to the remaining nucleus.
• A sequestrated disc is when the nucleus has been detached from the inside portion with the potential to migrate from the level of the disc.

Spondylolisthesis

• Spondylolisthesis refers to a condition where there is displacement of one lumbar vertebra over another or the sacrum.
• Pathologically, congenital, isthmic, adult degenerative, traumatic, and postsurgical are classifications
• Isthmic types and adult degenerative types are the commoner types found in the adult population.

Spinal Stenosis

• Refers to the narrowing of the spinal canal, most commonly seen in the lumbar region.
• Results in symptoms of neurogenic claudication, with or without back pain, neurological deficit and disability.
• Typically presents in patients in their mid-50s, progressing in the next decade of life; those with congenitally narrow spinal canals may present earlier.
• Causes of claudication are varied, including increase in intradural pressure, reduction of blood flow with decreased nutrition, and compression of the spinal cord at multiple levels.
• Symptoms can mimic other conditions, such as vascular disease or myelopathy.

Osteoporotic Vertebral Fracture

• Collapse of the vertebral body due to osteoporosis occurs at the thoracolumbar junction, leading to acute onset of back pain with kyphotic deformity.
• Postmenopausal women with a dualenergy X-ray absorptiometry (DEXA) value of less than -2.5 are at high risk of such fractures.

Failed Back Surgery Syndrome

• Persistent, recurrent, or worsening back pain with disability after previous spine surgery is defined as failed back surgery syndrome; It develops in 10–20% of postoperative patients. -The rate varies between different preceding procedures.
• Causes include inappropriate or inadequate surgery of the pre-existing pathology, recurrence of the pre-existing pathology, new disease at a different level, or complications due to previous surgery.
• Patients may present with back or leg pain, which should be assessed diligently and systematically.

Scoliosis

• Musculoskeletal cause of back pain
• Sciatica from a bulging or herniated disc pressing on the sciatic nerve causes sharp, shooting pain through the buttock and back of the leg
• It may cause numbness, muscular weakness, pins and needles or tingling, and difficulty in moving or controlling the leg.
• Symptoms are typically only felt on one side of the body.
• Specific low back pain can be from degenerative disc disease.

Degenerative Disc Disease

• The intervertebral disc is an avascular structure that attains its nutrition from the surrounding vertebral endplate and bears the load between vertebral bodies.
• The nucleus pulposus is the centrally located hydrophilic structure composed mainly of a type II collagen network and a gelatinous proteoglycan core which imbibes water.
• The annulus fibrosus is the outer layer of the disc, with overlapping lamellae of type I collagen, withstanding most tensile, torsional, and radial stress across the intervertebral bodies.
• The vertebral endplate surrounds the disc and provides nutrition by diffusion.
• The degenerative process will lead to decrease in water content and disc space.
• Collagen content at the annulus changes with fissuring and radial tears, causing the disc to budge out.
• Extrusion of the disc material may occur at the annulus defect.
• With these pathological changes, the disc can become a source of pain.
• Preceding trauma before changes occur are referred to as internal disc disruption.
• The annulus is a heavily innervated structure, facilitating the escape of protein from the annulus tear as a noxious stimulus to the nearby nociceptors.

Spondylosis

• It is a generally used term to describe the degenerative process affecting the axial skeleton.
• Spondylosis is a natural aging phenomenon, but is associated with severe degeneration with pain.
• Clinical diagnosis cannot be easily differentiated from non-specific back pain.

Ankylosing Spondylitis

• Ankylosing spondylitis is a noninfectious inflammation of the spine and is a chronic inflammatory disorder characterized by the ossification of intervertebral discs, joints, and ligaments leading to progressive rigidity of the spine.
• Ankylosing spondylitis can cause stiffness and pain in the spine that is worse in the morning.
• Ankylosing spondylitis typically begins in adolescents and young adults.
• It is a form of arthritis that is long-lasting (chronic) and often affects the spine and SI joints, immune mediated, and progressive.
• The disease affects joints in the spine and the sacroilium in the pelvis, causing fusion of the spine; men are affected more than women by a ratio about of 3:1.
• Ankylosing spondylitis can cause mild to severe back and buttock pain, worse in the early morning with morning stiffness lasting more than 30 minutes.
• The pain decreases with activity over time, and causes continued inflammation of the ligaments, tendons, joint capsules and spine.
• Ankylosing spondylitis leads to less motion in the neck and low back, with the neck and low back losing their normal curve, and can cause kyphosis and significant disability.

Infections

• Infections can cause pain when they involve the vertebrae, a condition called osteomyelitis, and are not common causes of back pain.

Tumors

• Tumors are relatively rare causes of back pain, occasionally beginning in the back, but more often appearing in the back as a result of cancer that has spread from elsewhere.
• The three most common cases are prostate cancer, breast cancer and lung cancer.

Others

• Osteoporosis, pregnancy, kidney stones or infections, endometriosis, and fibromyalgia are among other causes of back pain.
• Osteoporosis is associated with a reduction in bone mass, making the bone weaker and more brittle, leading to an increased risk of fracture.
• Spinal fractures from osteoporosis can cause back pain.
• If there are enough fractures within a vertebra, the entire vertebra may compress to a wedge shape or collapse completely, which is known as a compression fracture.

Referred Pain and Cauda Equina Syndrome

• Pain may be referred from kidney and other organs
• Cauda equina syndrome is a rare but serious condition and a serious neurological problem affecting a bundle of nerve roots that serve the lower back and legs due to compression or trauma.
• It can cause weakness in the legs, numbness in the "saddle" or groin area, and loss of bowel or bladder control.
• Diagnosis should include a history taking that details the course of pain, evidence of a systemic disease or neurologic problems, occupational history, risk factors, red flags, and yellow flags.
• History should include primary site of pain, radiation of pain, character of pain, and intensity of pain at rest or on movement.
• Factors affecting pain like stiffness at rest or at night and decrease with movement should also be evaluated.
• Inquire if pain is present continuously or otherwise, and how it effects activities and sleep.
• Risk factors in the history include if it is genetic or acquired, body-weight distribution, psychosocial factors, and occupational factors.
• Evaluate heavy physical work, nightshifts, lifting, bending, twisting, pulling, pushing, psychological factors, smoking, and long-term medication.

Red Flags

• These are patient signs, symptoms, or history that indicate possible serious pathology and hence support the decision to image the lower back.
• Such red flags are onset age either <20 or >55 years, presence of bowel or bladder dysfunction, spinal deformity, and weight loss.
• Other red flags include lymphadenopathy, neurological symptoms, history of HIV, corticosteroid therapy, unexplained fever, and duration more than 6 weeks.

Yellow Flags

• Psychosocial patient factors are not associated with serious organic pathology but indicate an increased likelihood of chronic back pain and resultant long-term disability and potential loss of work.
• These yellow flags include if a patient believes that the back pain is serious, fear avoidance behavior, work-related factors, prior episodes of back pain, and extreme symptoms.

Mechanical Back Pain

• Is deep, dull, and moderate in nature, relieved by rest, and increased by activity, possibly caused by injury and with previous episodes.
• This pain is diffuse, unilateral, and increases in intensity by the end of the day and after activity, and can also be postural from sitting in a poorly designed, unsupportive chair.

Inflammatory Back Pain

• Has a gradual onset, throbbing in nature, morning stiffness, and it exacerbates by rest but is relieved by activity.
• The pain intensity is increased in the night and early morning, and it is a chronic backache.

Nerve Root Compression

• Triggers intense sharp or stabbing pain with numbness and paraesthesia in the same distribution, and radiates to a dermatome like the foot or toe.
• Examination includes assessment for deformity, scoliosis, kyphosis, loss of lumbar lordosis or hyperlordosis of the lumbar spine, and look for shoulder asymmetry and pelvic tilt.
• Observe the patient walking and perform an abdominal examination to identify masses, pain in the legs, and unilateral or bilateral lower limb motor and/or sensory abnormality.
• Ranges of movement and limitation should be assessed, including Flexion, Extension, Lateral Bending and Rotation.
• Straight leg raises by raising the patient's extended leg with the ankle dorsiflexed; it normally raises 80 – 90 degrees with no pain is limited by sciatica pain in lumbar disc prolapse (<70) or exactly from 30 to 70.
• Neurologic testing should focus on the L5 and S1 nerve roots.
• 98% of disc herniation occur at L4-5 and L5-S1.
• Assess Reflexes with L4 for the knee reflex, and S1 for the ankle reflex.
• Motor functions to assess includes: ankle plantar flexion (S1) and ankle dorsiflexion (L5) which also includes L4.
• Imaging modalities include: First line Xrays if red flags or osteoporotic fracture, bone scan, CT scan, MRI, and Dexa Scan.
• X-rays are good first line investigation if red flags are found or there is osteoporotic fracture.
• Bone scans are helpful if Xray is normal but with red flags, they help identify mets, infection, pagets and PMR.
• CT scans help determine bone tumours, fractures and spinal stenosis.
• MRI helps with imaging spinal cord, nerve roots, discs, haemorrhage
• A Dexa Scan is helpful for assessment of bone density
• Management options include oral drugs, local injections, and non-drug therapies.

Management

• Oral drugs generally used are NSAIDs like Ibuprofen, analgesics like Antidepressants & muscle relaxants, local injections epidural steroids, trigger point injections and ligament injections.
• Non-drug therapy include heat therapy, physiotherapy and acupuncture.
• Heat therapy dilates the blood vessels of the muscles surrounding the lumbar spine, as well as facilitates stretching the soft tissues around the spine, including muscles, connective tissue, and adhesions, and decrease in stiffness, increasing flexibility.
• Acupuncture typically involves inserting very thin needles to various depths into strategic points on the body and is generally recognized as safe if done by a competent, certified acupuncture practitioner.
• Possible side effects and complications can occur, which include soreness, bleeding, infection or bruising at the needle sites.
• Surgery may sometimes be appropriate for patients with lumbar disc herniation, lumbar spinal stenosis, spondylolisthesis, scoliosis, and compression fracture.
• The majority of herniated discs will heal on their own in about six weeks and do not require surgery.
• If the patient has red flags, a referral to surgery is required after conservative therapy has been tried.
• Conservative treatment is enough and surgery usually does not solve the problem.
• The traditional medical management of scoliosis is complex and is determined by the severity of the curvature, and can include observation, physiotherapy and surgery.
• Patients with symptomatic spondylolisthesis are initially offered conservative treatment with activity modification, 2- Medications , 3- Physiotherapy.
• Osteoarthritis, can be addressed with lifestyle modification with weight loss and exercise.

Ankylosing Spondylitis Treatment

• No cure available; treatment and medications are available to reduce symptoms and pain, physical therapy and exercise, are sufficient.
• Treatment of underlying cause for others:
  • Tumors
  • Osteomyelitis
  • Sciatica
  • Osteoporosis
• Patient should be referred to a specialist when Cauda equina syndrome is the cause, with severe or progressive neurologic deficits, infections, and tumors.
• A referral should be given if the patient shows fractures compressing the spinal cord, or if there is no response to conservative therapy for 4 to 6 weeks for patients with a herniated lumbar disk or 8 to 12 weeks for those with spinal stenosis.
• Red flags suggesting a serious back condition include: age ≥ 50 years or unexplained weight loss, neurologic findings and lymphadenopathy, age ≥ 55 years with osteoporosis being a Housewife, presence of Fever, chills and is Immunocompromised.