The anatomy of the spine consists of the upper part of the back, the lower part of the back, and the neck.
An inside look at the structure of the back
When most people mention their back, what they mean is their spine. The spine extends from the base of your skull along your back until you reach the pelvis.
It consists of 33 reel-shaped bones called vertebrae, each about an inch thick and stacked on top of the other.
Each vertebra consists of the following parts:
The body is the most significant part of the vertebrae and the part that has more weight.
The lamina is the lining of the orifice (spinal canal) through which the spinal cord runs.
The spinous process is the bony protuberances you feel when running your hand down your back.
The transverse processes are the pairs of protuberances on each side of the vertebrae to which the back muscles join.
The facets are two pairs of protuberances where the vertebrae connect, which include:
- The upper articular facets look up.
- The lower articular facets look down.
The connection points between the vertebrae are known as the facet joints, which keep the spine aligned as it moves.
Like other joints in the body, the facet joints are lined with a smooth membrane called the synovial membrane, which produces a viscous fluid to lubricate the joints.
Located between the individual vertebrae, the discs serve as cushions or cushions between the bones. Each disk has approximately the size and shape of a flattened threaded hole and consists of two parts:
- The fibrous annulus: a solid outer covering.
- The nucleus pulposus: a “gelatinous” filling.
In the center of the spine is the spinal cord, a set of nerve cells and fibers that transmit electrical signals back and forth between the brain and the rest of the body through 31 pairs of nerve bundles that branch into the brain: spinal cord and the spine between the vertebrae.
Support for the spine, while providing flexibility, are ligaments (hard bands of connective tissue that connect bone to bone) and muscles. Two main ligaments are:
- Anterior longitudinal ligament
- Posterior longitudinal ligament.
Both work along the back and hold all the spine components together.
The two main muscle groups involved in back function are:
- The extensors: include the many muscles that attach to the spine and work together to keep your back straight while allowing you to extend it.
- The flexors adhere to the lumbar spine (lower back) and allow you to lean forward. The flexors at the front of your body include the abdominal and hip muscles.
Although the spine is a continuous structure, it is often described as five separate units. These units are the five different sections of the spine:
- The cervical spine: the neck and the upper part of the back, composed of the seven vertebrae closest to the skull. The cervical spine supports the weight and movement of the head and protects the nerves that come out of your brain.
- The lumbar spine: the lower part of the back, composed of five vertebrae, provides support for most of the weight of your body.
- The thoracic spine is the middle part of the back, formed by the 12 vertebrae between the cervical and lumbar spine.
- The sacrum is the base of the spine composed of five vertebrae fused as a solid unit. The sacrum joins the ilium of the pelvis, forming the sacroiliac joints.
- The coccyx: is located below the sacrum, composed of four fused vertebrae.
The causes of back pain are almost as numerous as the terms used to describe the symptoms. Back pain is the main reason why people seek medical attention.
Considering that almost 80% of the adult population will encounter some back pain, one could say that back pain is a universal epidemic. Back pain does not recognize age, economic or ethnic barriers.
Acute Pain – Chronic – Episodic
Typically, back pain originates in the neck (cervical), mid-back (thoracic), lumbar, or a combination such as “thoracolumbar pain.” Depending on the source of the pain, certain types of pain may be indicative of a particular disease or disorder.
The pain can be described as sudden, sharp, persistent, or dull. Symptoms may be localized to a specific area of the back (for example, the neck) or radiate to the shoulders, arms, lower back, buttocks, legs, and even feet.
Sometimes, the pain is accompanied by neurological symptoms such as numbness, tingling, or weakness.
Back pain is acute or chronic. Acute pain can start suddenly with severe pain that usually lasts a short period. Chronic pain is persistent pain in the long term, which sometimes lasts a lifetime. Even chronic pain can present episodes of acute pain.
Specific neurological symptoms may indicate the need for immediate medical attention. These ‘red signals’ include bowel or bladder dysfunction, weakness or numbness of the extremities, severe symptoms that do not go away after a few days, or pain that prohibits everyday activities.
One of the causes of back pain is muscle distension and spasm. Tension can result from “weekend warrior syndrome,” heavy physical work, uncomfortable flexing or twisting, and poor posture.
Whiplash is neck pain that commonly occurs after a car accident. This is usually caused by hyperextension and hyperflexion because the head is forced to move backward and forward rapidly beyond the normal range of motion of the neck.
The unnatural and forceful movement affects the muscles and ligaments in the neck. The muscles can react by tightening and contracting, creating muscle fatigue, resulting in pain and stiffness.
Spinal osteoarthritis or spondylosis is a degenerative disorder that can cause the loss of standard spinal structure and function. Although aging is the leading cause, the location and rate of degeneration are individual.
The degenerative process can affect the cervical, thoracic, and lumbar regions of the spine that affect the discs and spinal joints.
Osteoporosis commonly affects the thoracic and thoracolumbar regions of the spine and can cause debilitating pain. This disorder is caused by a loss of bone mineral density that results in brittle bones, which can fracture.
Osteoporosis can cause vertebral compression fractures, loss of height, stooped posture, and even a hunched back. The patient can control some of the risks of osteoporosis. These include a poor diet, smoking, excessive alcohol consumption, and inactivity.
A herniated disc is a ruptured disc. This can occur if the nucleus pulposus (a center similar to a gel) erupts through the fibrous annulus (protective disc wall) or the annulus fibrosis becomes fragmented. Progression to an actual hernia varies from slow onset to sudden symptoms.
There are four stages:
- Protrusion of the disc.
- Prolapsed disc.
- Extrusion of the disc.
- Disco hijacked.
Stages 1 and 2 are incomplete, whereas 3 and 4 are complete hernias.
“sciatica” is commonly used to describe pain that travels along the sciatic nerve, the largest nerve in the body.
The pain may be acute, dull, burning, or accompanied by intermittent discharges of throbbing pain that start in the buttock and descend to the back of the thigh and leg. The most common cause of sciatica is a herniated disc in the lumbar spine.
A compression fracture is a common spine fracture that can vary from mild to severe. Each vertebral body is separated from the other with a disc.
When an external force is applied to the spine, such as a fall or a sudden heavy weight, the forces can exceed the capacity of the bone within the vertebral body to support the load. This can cause the vertebral body to collapse.
This is called a compression fracture. If the entire vertebral body is broken, this is considered a burst fracture.
Spinal stenosis occurs when small neural ducts are called narrow foramen. The narrowing of the foramen can compress and trap the nerve roots.
The nerves react to the pressure when swelling, reducing the foraminal space. Stenosis can cause unbearable pain, numbness, tingling, or burning in the affected limb (e.g., leg, arm).
Stenosis can also occur with disc compression, osteophytes (bone spurs), and ligaments.
Scoliosis causes the spine to curve laterally to the left or the right and affects children and adults. Scoliosis is a complex three-dimensional disease. To understand this concept, consider that, in some cases, the affected vertebrae are forced to rotate as the spine abnormally curves.
At the thoracic level, the vertebral turn impacts the rib cage and can result in the prominence of the ribs on the opposite side of the curve. The deformity is the main complaint. Back pain from scoliosis is uncommon.
Spinal infections ( osteomyelitis )
Osteomyelitis is a bone infection usually caused by bacteria. The spine is commonly found in the vertebrae, although the infection can extend to the epidural and intervertebral disc spaces.
Typically, symptoms include persistent and severe back pain aggravated by movement, swelling, fever, sweating, weight loss, and general malaise.
Determine the cause
Back pain is not always indicative of a spinal problem. Rarely is back pain an emergency or a severe medical condition? An adequate diagnosis is essential to determine the best course of treatment. A complete physical and neurological evaluation can reveal the cause of the pain.
The examination begins with the patient’s current condition and medical history.
The oral segment of the exam often includes many questions such as “when did the pain begin?” – “what activities preceded the pain?” – “pre-treatment” – “does the pain radiate or travel to another part of the body?” – “What makes the pain less or greater?” – etc.
This examination includes observing the patient’s posture, range of motion, and physical condition. Any movement that generates pain is noted.
The doctor will feel the curvature of the spine, and the vertebral alignment will detect the muscles and sensitive points. Abdominal palpation can be performed to determine if the cause of low back pain is possibly related to an internal organ (e.g., the pancreas).
The neurological examination evaluates the patient’s reflexes and muscle strength, detects sensory and motor changes, and determines the distribution of pain. If nerve damage is suspected, the doctor may order special tests to measure the speed at which the nerves conduct the impulses.
These tests are nerve conduction velocity (VCN) and electromyography (EMG). These studies are generally not done immediately since the nerve condition may take several weeks to manifest.
If infection, malignancy, fracture, or other risk factors are suspected, routine laboratory tests can be ordered. These tests may include complete blood count, erythrocyte sedimentation, and urinalysis.
Simple radiographs (x-rays), computed tomography, and magnetic resonance imaging are performed when a disc or fracture is suspected or to assess neurological dysfunction. An MRI represents the gold standard in images today.
An MRI represents high-resolution images of the spinal tissues, such as the spinal cord and the intervertebral discs. X-rays are still the imaging method of choice to study bone elements in the spine.
Non-Conservative Nonsurgical Treatment
Rarely back pain requires surgical intervention. A conservative treatment plan may include bed rest for a day or two combined with medications to reduce inflammation and pain.
The medications recommended by the doctor are based on the patient’s medical condition, age, other medications the patient is taking, and safety.
The first option for pain relief is often nonsteroidal anti-inflammatory drugs. These medications should be taken with food to reduce the risk of upset stomach and stomach bleeding.
Muscle relaxants can relieve muscle spasms but are mild sedatives that often cause drowsiness. Narcotic analgesics may be prescribed for use during the acute phase.
A cervical collar may be recommended to help a patient with neck pain. Cervical collars limit movement and support the head by removing the neck load. Lying down has a similar effect.
Limiting neck movement and reducing pressure (weight) provide the muscles with the necessary rest while healing.
Cervical traction can be prescribed for home use. This traction pulls gently on the head, stretching the neck muscles while increasing the neural ducts (foramen) size.
Physical Therapy (TF) can be incorporated into the patient’s treatment plan once the activity can be tolerated. TF may include ice therapy to decrease nerve conduction, thus decreasing inflammation and pain. Heat treatments can be used to accelerate the repair of soft tissues.
The heat increases blood flow and accelerates the metabolic rate to aid healing. The heat also helps decrease muscle spasms and pain and promotes relaxation.
Ultrasound is a treatment used to administer heat to soft tissues. Sometimes, a heat treatment is administered before a session of therapeutic exercise.
Therapeutic exercise can help develop strength, increase range of motion, coordination, stability, and balance, and promotes relaxation. Therapists educate patients about their condition and teach posture and relaxation correction techniques.
Patients who participate in a structured physical therapy program often progress to the well-being more quickly than those who do not. This includes back maintenance through an exercise program at home developed for the patient by the physiotherapist.
Surgery: Required Selection
Surgery is rarely required to treat back pain.
Indications for surgery include, among others, spinal cord dysfunction, bowel and bladder dysfunction, excruciating pain (most often, pain in the leg is more significant than back pain) not relieved by nonsurgical measures, and prolonged pain and weakness.
Recovery and Prevention
First, follow the treatment plan delineated by the doctor and the physiotherapist.
Patients who undergo a surgical procedure may find that the road to recovery is a bit longer. However, that is no reason to be discouraged. It is normal to feel tired and emotionally depressed after surgery.
During stress, such as surgery, the body produces additional hormones: after surgery, the level goes down, which can cause a period of inactivity.