Lumbar spine: Anatomy and 16 pathologies explained

anatomy of intervertebral discs and spine
Contents

Article reviewed and approved by Dr. Ibtissama Boukas, physician specializing in family medicine 

Located between the dorsal region and the sacrum, the lumbar spine forms the region of the lower back. It can be the site of several pathologies due to the many constraints it undergoes.

What is the lumbar spine, and what are the most common symptoms encountered with a problem at this level? When should you worry? What are the treatments available today to fight back pain?

This popularized article explains everything you need to know about the anatomy of the lumbar spine, and the management of the pathologies that result from it. 

Definition and anatomy of the lumbar spine

The lumbar spine is part of the spinal column. Located between the dorsal spine and the sacrum, it is made up of 5 bones, or vertebrae, numbered from L1 to L5. The vertebrae are separated from each other by intervertebral discs. These discs help absorb shock and also facilitate back movement.

A vertebra is made up of a vertebral body at the front, and a bony arch at the back. The space between the body and the posterior arch forms a channel that runs the entire length of the back. It is called the spinal canal (or spinal canal).

It is in this space that the spinal cord passes, although it ends at the L2 level and leaves room for the ponytail. There are also spinal nerves (via openings called foramina) on either side of the spine. The nerves that originate in the lumbar region will travel to the lower limbs to provide sensation and movement.

The lumbar spine is supported by a series of muscles and ligaments attached to the vertebrae. These structures will allow the stability of the trunk, the movements, as well as the protection of the organs.

Pathologies of the lumbar spine

The lumbar spine can be the site of several pathologies. These can be traumatic (after an accident) or appear gradually.

Essentially, any damage to the discs, muscles, ligaments, vertebrae, or joints in the neck can cause lower back pain, and other dysfunctions.

Among the most common pathologies are:

Symptoms of the disease

Obviously, the symptoms observed will depend on the pathology. To know the symptoms caused, it is necessary to understand the anatomical and physiological role of the irritated structure.

The symptoms will also depend on the individual concerned, as the body's ability to adapt and tolerance to pain is different for everyone.

For example, nerve damage could cause pain to radiate to the legs, as well as numbness and tingling in the lower limbs.

Ligament damage could cause local pain aggravated by movements putting tension on the ligaments concerned (such as twists).

Muscle damage could cause local inflammation, and limit movements involving contraction of irritated muscles.

In short, here is a list of symptoms often associated with conditions of the lumbar spine:

  • Lower back pain
  • Pain referred to the mid back and shoulder blade
  • Pain radiated to the lower limb (hip, knee, ankle, foot)
  • Numbness and tingling in the feet
  • Burning sensation
  • Feeling of weakness in the legs
  • Crunches

Physical examination

When consulting a health professional for a lumbar spine disorder, he will generally follow a structure to clarify the situation, and then issue one (or more) diagnostic hypothesis (s).

The examination will most often begin with a medical questionnaire where you will be asked questions about your health, your pain and other symptoms, the impact on your daily life, your goals, etc.

Then, the professional will do a clinical examination. The primary objective is to exclude serious damage (such as cancer, or damage to the spinal cord) that would constitute a medical emergency.

This notably involves neurological tests (Clonus, Babinski, reflexes, sensation, muscle strength, coordination, vision, etc.).

Once serious damage has been excluded, movements of the lumbar spine such as flexion, extension, rotations and lateral tilts will generally be evaluated. This will give us information about the irritated structures.

Other more advanced clinical tests will help clarify the diagnosis and guide treatment.

Medical imaging of the cervical spine

Sometimes, the clinical examination of the health professional is not enough to determine with conviction the pathology of the lumbar spine.

In this case, the doctor will order a medical imaging test. It should be noted that these tests are not recommended immediately, because it has been noted that a dysfunction observed on medical imaging does not necessarily explain the patient's pain.

Here are the most common medical imaging tests prescribed by doctors:

  • X-ray
  • Lumbar scan
  • Lumbar MRI
  • CT scan
  • EMG

When to worry

As mentioned previously, one of the main objectives during the physical (and radiological) examination is to exclude serious damage to the lumbar spine.

This includes in particular any systemic damage (such as cancer in the most serious cases), or damage to the spinal cord.

Here are the situations where an attack of the lumbar spine would worry the medical profession. Often, they are emergencies, even going as far as surgery:

  • Pain following severe trauma: If your pain is relatively recent and it appeared after a major event (such as a fall from a height or a road accident), you should consult. 

  • Constant, progressive, non-mechanical pain: You can't find any resting positions and none direction of movement does it seem to relieve your symptoms? Go see a doctor to clarify the situation. 

  • Severe chest or abdominal pain: It is common for lower back pain to expand, but if you have excessive pain around the lower back area, it is a sign that you need to consult.
  • Constant night pain: If your nights are painful and you can't find positions to relieve your pain, seek a doctor's opinion (even more so if you have night sweats, chills or a fever!)
  • Unexplained weight loss: You haven't gone on a diet and you haven't started an exercise program, but you seem to be losing weight over the weeks? Speak to your doctor immediately! 

  • Saddle anesthesia: If you have any sensory impairment in the region of the perineum (such as strange sensations in the area of ​​the genitals), this should require the intervention of a doctor.
  • Urinary or fecal incontinence of recent onset: I dare to hope that you will consult immediately if you lose control of your sphincters!

Available treatments

Fortunately, serious damage to the lumbar spine is rare, and the vast majority of pathologies can be treated.

Often, the doctor is consulted in first intention following lumbar pain. He can then refer to a competent therapist, or even a specialist for more complex cases.

In chronic cases, it should be noted that a multidisciplinary team where providers work as a team generally provides the best results.

Here are the most commonly used treatment modalities:

Conclusion

The lumbar spine is a very important structure because of the stability it provides to the rest of the body. It is formed by the juxtaposition of 5 lumbar vertebrae located in the lower back.

Given its position and its role, the lumbar spine can be the site of several pathologies, whether traumatic or progressively installed. The symptoms will mainly depend on the irritated structure, as well as the level of inflammation.

A clinical and radiological examination will exclude serious damage requiring urgent medical intervention, and will clarify the diagnosis.

Treatments provided by healthcare professionals are generally effective in relieving pain and improving quality of life.

Good recovery !

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