The human spine is one of the most important structures in the body. It gives us structural support and integrity, allowing us to stand, move, bend and twist while performing countless everyday tasks.

The spine is also designed to protect the spinal cord – the column of nerves that connects the brain with the rest of the body and allows you to control movement. Without a functioning spinal cord, you could not move, and your organs could not be properly coordinated. That is why keeping the spine healthy matters so much. This article covers the two most important functions of the spine and why they are worth protecting.

Spine Anatomy

Before looking at its primary functions, it helps to understand the spine’s anatomy. As an adult, your spine is made up of 24 movable bones that stack to create the spinal column. Between each bone sit shock-absorbing cushions called discs, which also create space for spinal nerve roots to exit and keep the bones from grinding against one another.

The spine also has ligaments that connect bone to bone, tendons that attach muscle to the vertebrae, and small joints called facet joints – much like the elbow or knee – that link the vertebrae and give them flexibility to move against each other. Every vertebra has a hole in the center, and stacked together these form a protective tube for the spinal cord and nerve roots. The spine is organized into three sections: the cervical (neck), thoracic (mid-back) and lumbar (lower back).

Together, these structures enable the spine’s two most important functions: structural support, and armor for the spinal cord and nerves.

Stages of Structural Degeneration of the Spine

The Spine Gives Structural Support

A healthy spine has three natural curves that form a gentle S-shape. These curves absorb shock and protect the spine from injury. When they are lost, the body tends to break down prematurely, accelerating osteoarthritis and degeneration. The structural support system of the spine is made up of:

Vertebrae – the individual bones that stack to form the spinal column and house the spinal cord. Most vertebrae move to allow range of motion; the lowest ones (sacrum and coccyx) are fused and do not move.
Facet joints – cartilage-lined spinal joints that let the vertebrae slide against one another, providing both flexibility and stability. They can develop arthritis and cause neck or back pain.
Intervertebral discs – flat, round cushions between the vertebrae that act as shock absorbers, each with a gel-like center (nucleus pulposus) and a flexible outer ring (annulus). They are under constant pressure and can tear, allowing the gel to leak – a herniated disc.
Spinal cord and nerves – the cord runs through the spinal canal from the skull to the lower back, with 31 pairs of nerves branching out through the vertebral openings to carry messages between brain and body.
Soft tissues – ligaments hold the spine in position, muscles support the back and enable movement, and tendons connect muscle to bone.

Failure to maintain normal spinal alignment can cause abnormal motion of these structures, which over time contributes to spondylosis – an umbrella term for age-related spinal degeneration. Spondylosis can lead to facet arthritis, weakened discs, nerve impingement and ongoing soft-tissue problems such as muscle spasms and strained ligaments and tendons.

The Spine Protects the Spinal Cord and Nerves

The spinal cord is a column of millions of nerve fibers running through the spinal canal. It extends from the brain to roughly the first or second lumbar vertebra, where it divides into a bundle of nerve fibers called the cauda equina that continue toward the lower body before exiting through the neural foramina.

The nerve fibers branch into pairs of nerve roots that pass through the small openings between vertebrae, and each connects to a specific part of the body. This is why a spinal cord injury can cause loss of function in some areas but not others, depending on which nerves are affected. Paralysis is the extreme example, but many people experience lesser spine-related dysfunction from abnormal alignment and motion.

The nerves of the cervical spine serve the upper chest and arms, the thoracic nerves serve the chest and abdomen, and the lumbar nerves reach the legs, bowel and bladder. These nerves help coordinate the body’s muscles and organs and carry sensory signals back to the brain. Damage to a nerve can cause pain, tingling or numbness along the path it travels.

Conditions Linked to Spinal Deterioration

Most people seek care for their spine because of pain, but repeated injury and dysfunction can contribute to broader problems over time. Common structural conditions associated with an unhealthy spine include:

Arthritic conditions such as ankylosing spondylitis
Back strains and sprains
Birth defects such as spina bifida
Bone spurs that press on the spinal cord and nerves
Curvatures of the spine (scoliosis and kyphosis)
Neuromuscular diseases such as ALS
Nerve conditions including spinal stenosis, sciatica and pinched nerves
Osteoporosis
Spinal cord injuries, including fractures, herniated discs and paralysis
Spine tumors and cancer
Spine infections such as meningitis and osteomyelitis

In cases of serious spinal cord injury, the downstream effects can extend to many body systems – including respiratory, cardiovascular, urinary, muscular, skeletal and immune function. These are most associated with significant cord-level injury rather than everyday aches, which underscores why protecting the spine matters.

How to Keep Your Spine Healthy

The first step is assessing the state of your spine: Do you have normal alignment and movement? Are the attached structures functioning well? Do you have healthy curves in the neck, mid and lower back?

Among all the treatments studied for back pain, strength training has some of the strongest supporting evidence. Strong back and core muscles help protect the spine and prevent problems, so daily strengthening and stretching are valuable. Exercises like planks build the core to give the spine more support. Other protective measures include: