Spinal Hernia: What It Is, How It Develops, and How It Manifests

The diagnosis of "spinal hernia" sounds serious, although it refers to a protrusion of part of an intervertebral disc. The spine is a system of levers made of 26 bones, with soft pads containing a jelly-like core between them. Below is how such a hernia is structured, why it occurs, and what an examination shows.

What an intervertebral disc hernia is

A disc consists of a dense fibrous ring and a soft nucleus inside. The nucleus bears the load, and the ring keeps it in place. An intervertebral hernia is a protrusion (extrusion) of the nucleus into the spinal canal due to a breach in the integrity of the ring. A milder condition, in which the nucleus bulges but the ring remains intact, is called a protrusion.

A protrusion is not always painful: if the disc presses on a nerve, there is pain; if it does not press, a person may never learn about their hernia. Height is greater in the morning than in the evening because discs compress under load, and this is physiological.

How a disc hernia develops: causes and risk factors

The main factor is disc degeneration, that is, gradual wear. An adult disc has no blood supply of its own: nutrition occurs during movement, for example when walking. With a sedentary lifestyle, nutrition is insufficient, the disc loses water and becomes fragile. Heredity also affects fragility.

There are three groups of causes: genetic, metabolic or nutritional disturbance, and mechanical — constant microtrauma and gradual destruction of disc structures. External risk factors: lifting heavy objects, torsional loads (lifting with twisting), driving a car, age, excess weight, physical inactivity, prolonged sitting, overly strenuous training. Smoking weakens disc tissue.

Where hernias occur and what types they are

Most often, intervertebral disc hernia occurs in the lumbosacral region — 150 cases per 100,000 population per year. The cervical region is affected significantly less often, and the thoracic region least often. In the lumbar region, 48% of hernias occur at the L5–S1 level, 46% at L4–L5, and the remaining 6% at other levels or at several levels at once.

By degree of protrusion, a distinction is made between protrusion, when the ring is intact, and hernia with rupture of the ring. Surgery is needed relatively rarely: in the USA, more than 200 thousand such procedures are performed annually, and in Germany, 20 thousand.

How spinal hernia manifests

Symptoms depend on which root is compressed. Common signs: pain in the lower back or neck, numbness and tingling in the shoulders, back, arms, hands, legs, or feet, muscle weakness, difficulty bending and extending the back. If the disc presses on the sciatic nerve, pain radiates to the buttocks, thigh, or leg — this is sciatica.

• L4 root (L3–L4 disc): pain in the anteromedial parts of the thigh and lower leg, weakness of the quadriceps muscle, decreased knee reflex.
• L5 root (L4–L5 disc): pain from the upper gluteal region to the lateral parts of the thigh and lower leg, sometimes to the dorsum of the foot and the first three toes.
• S1 root (L5–S1 disc): pain from the middle gluteal region to the posterior parts of the thigh, lower leg, and heel, weakness of the calf muscle, decreased Achilles reflex.
• Cervical roots: with compression of C5, the deltoid muscle is affected; with C6, the lateral edge of the arm down to the first finger; with C7, the dorsum of the hand and the three middle fingers.

How intervertebral hernia is diagnosed

Usually the diagnosis is made based on symptoms and examination: the doctor checks reflexes, sensation, and muscle strength, asks the patient to raise the arms or perform simple leg movements to identify the level. The method of choice is MRI or multislice CT. If necessary, non-invasive MR myelography or invasive CT myelography is performed.

Possible complications and when urgent help is needed

In most cases, symptoms subside within a few weeks, partly due to spontaneous resorption of the hernia. In 73% of patients, marked improvement occurred without surgery within 12 weeks after the onset of symptoms. But relief does not cancel root syndrome — injury and inflammation of the nerve roots. Numbness in the perineal area, urinary retention, and loss of sensation in the legs are emergency signs.

An appointment with a doctor is made without haste if the pain does not subside after several weeks, there is a high temperature, chills, unexplained weight loss, swelling on the back, or the pain intensifies at night.

A disc hernia by itself is not a reason to call an ambulance. Numbers 103 and 112 are needed if, against the background of back pain, the buttocks or genital organs become numb, there is no urine, sensation is lost in one or both legs, urine and stool are not retained, and also if the pain appeared after a serious accident.

This material is for reference: it explains what happens to the disc but does not replace a doctor's consultation — examination and decisions on management remain with the specialist.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer