Lumbar Spine Anatomy and Movement Quiz

Lumbar Spine Problems

• The lumbar spine consists of five vertebrae (L1-L5), facet joints, and the sacrum.
• The vertebral column supports the upper body and protects the spinal cord.
• It transmits weight, helps with movement, and maintains stability.
• It's composed of 33 vertebrae and 23 intervertebral discs.
• The lumbar spine is divided into five categories: cervical, thoracic, lumbar, sacral, and coccygeal.

Objectives

• Students should know the clinical anatomy and biomechanics of the lumbar spine.
• Define low back pain syndrome (LBP).
• Students should be able to describe pathological classifications of LBP and common conditions.
• Students should understand the red flags for lumbar problems.

Facet Joint Orientation

• Superior facets face medially and backward, generally concave.
• Inferior facets face laterally and forward, generally convex.

Spinal Curves

• The spine has primary and secondary curves.
• The spinal cord runs through the spinal canal, containing the nerves and spinal cord.
• The primary curves are present at birth, while the secondary curves develop later.

Lumbar Ligaments

• Ligamentum flavum: Connects adjacent laminae, limiting flexion.
• Supraspinous and interspinous ligaments: Limit flexion.
• Intertransverse ligaments: Limit contralateral lateral flexion.
• Posterior longitudinal ligament: Limits flexion and reinforces annulus fibrosus.
• Anterior longitudinal ligament: Limits extension and reinforces the annulus fibrosus.
• Capsule of apophyseal joint: Supports facet joints.
• Iliolumbar ligament: Stabilizes L5/S1.

Normal Lumbar Disc

• Acts as a shock absorber between lumbar vertebrae.
• Represents 20-25% of the vertebral column's total length.
• Cartilaginous endplates hold the disc in place.
• Annulus fibrosus (outer band): Encases gel-like nucleus pulposus (inner substance).

Intervertebral Disc Function

• Allows for tilting of vertebrae, increasing range of motion at the inter-body joint.
• Without discs, only translatory motion would be possible.

Effect of Posture on Discal Pressure

• Sleeping positions have the lowest pressure on the discs.

Nerve Roots

• Nerve roots exit the spinal canal within small passageways between vertebrae and discs.
• Pain and symptoms develop when a damaged disc presses on the spinal canal or nerve roots. This can be called radiculopathy.

Low Back Pain (LBP)

• LBP is often self-limiting, resolving in 6-12 weeks in most cases.
• Less than 1% of LBP cases are due to serious conditions like tumors or infection.
• Common symptoms include back pain, leg pain, neurological symptoms, and spinal deformity.

Mechanical Low Back Pain

• Characterized by pain related to physical activity and time.
• LBP is commonly located in the lumbosacral region, buttocks, and thighs.

Nerve Root Pain (Radiculopathy/Sciatica)

• Pain originating from the spine affecting the leg or foot.
• Causes of nerve root pain include disc herniation, spinal stenosis, nerve root inflammation, tumors, Piriformis Syndrome, and postoperative scarring.

Risk Factor Evidence

• Age, heavy manual labor, repetitive lifting, postural stress, whole body vibration, monotonous work, poor physical fitness or trunk strength, smoking, and psychological factors (depression, stress, anxiety) influence lumbar problems.

Stages of Low Back Pain

• Acute LBP: Less than 4 weeks.
• Subacute LBP: 4-12 weeks.
• Chronic LBP: More than 12 weeks.
• Evaluation involves ruling out emergent or non-musculoskeletal causes first.

Red Flags

• Presentation age <20 years or onset >70 years.
• History of trauma.
• Constant, progressive, non-mechanical pain.
• Previous history of carcinoma, prolonged steroid use, or back-related infections (spinal osteomyelitis).
• Fever or recent infection.
• Systemically unwell or weight loss.
• Widespread neurologic symptoms, Cauda Equina Syndrome (urinary retention/incontinence, bowel incontinence), progressive motor weakness in the legs, gait disturbance, and inflammatory disorders (e.g. Ankylosing Spondylitis).

Lower Crossed Syndrome

• Results from muscle imbalances in the lower back.
• Characterized by weak abdominal and gluteus maximus muscles, and strong hip flexors (iliopsoas) and back extensor muscles.
• Weak gluteal muscles cause overactivity of hamstrings and erector spinae.
• Weakness of gluteus medius influences quadratus lumborum and tensor fascia latae.
• This is sometimes seen in conjunction with the upper crossed syndrome, and together are sometimes referred to as layer syndrome.

Nerve Root Impingement

• Narrowing of the intervertebral foramen caused by stenosis, facet joint degeneration, or herniated intervertebral disc.

Degenerative Lumbar Spinal Canal Stenosis

• Reduction of space in the spinal canal affecting nerve elements.
• Typically seen in older athletes.
• Symptoms include pain aggravated by standing or walking, radiating pain into the buttocks and lower extremities, and neurogenic claudication.
• Pain relief may come with forward lumbar flexion.

Causes or Types of Lumbar Spinal Stenosis

• Idiopathic (congenital/developmental).
• Acquired: Spondylosis(bone spurs), spondylolisthesis, scoliosis, ossification of the posterior longitudinal ligament, hypertrophied ligamentum flavum, and hypertrophied facet joints, and herniated disc.

Lumbar Disc Herniation

• Abnormal rupture of the nucleus pulposus (central portion of the disc) through the outer ring (annulus fibrosus).
• Typically involves L4-L5 or L5-S1 disc levels.
• 75% of lumbar herniated discs resolve spontaneously. - Leg pain and paresthesia are more symptomatic than back pain.

Lumbar Spondylosis

• Used to describe degenerative disorders of the spine.
• Disc degeneration is a common disorder associated with spondylosis.
• Onset is often gradual with no known cause.

Facet Joint Dysfunction

• Pathology of facet joints cause 40% of chronic LBP.
• Symptoms include pain aggravated by lumbar extension (compressing the posterior joint), pain relieved by lumbar flexion (separating the joint surfaces), typically clinical diagnosis, and pain occurring acutely with extension and rotation of lumbar spine.

No Localizing Neurological Symptoms

• Pain is typically non-radiating.
• Sudden onset or steadily increasing pain may indicate disc lesions.
• High response to facet manipulation is common.
• Advanced age, intervertebral disc degeneration, and degenerative spondylolisthesis are also possible risk factors.

Spondylolysis

• A stress fracture of the pars interarticularis.
• Commonly seen in young people who perform repetitive flexion and extension motions (ex: gymnasts).
• Often painless, unilateral or bilateral defects, low back pain, and occasionally posterior buttock/thigh pain but without neurological deficits.

Spondylolisthesis

• Vertebral body slipping on another, often inferiorly toward another vertebrae.
• Progression of spondylolysis may cause separation of vertebrae.
• Superior vertebrae slide anteriorly on the one below.
• Most notable in women and adolescents.

Lumbar Spine Signs and Symptoms

• Restricted range of motion is common.
• Sacral prominence and palpable "step-off"
• Loss of lumbar lordosis and development of lumbosacral kyphosis.
• Common occurrence of low back pain (75%) and occasional absence of symptoms altogether.

Questions (Page 51)

• List of open-ended questions for discussion were presented that the students could ask to clarify or expand on the material.

Test your knowledge on the anatomy and movement mechanics of the lumbar spine. This quiz covers topics such as coupling in neutral posture, movement of the nucleus pulposus, and the role of various ligaments. Perfect for students of anatomy or physical therapy.