L5 syndrome

If the spinal nerve roots at the level of the fifth lumbar vertebra (L5) are affected by irritation, a characteristic complex of symptoms results, which is also known as L5 syndrome. The L5 syndrome is mainly characterized by pain along the back of the thigh, the outside of the knee, the lower leg up to the back of the foot and the big toe. The most common cause of nerve root irritation at this height is, as in other sections of the spine, herniated discs.

If a prolapse of the intervertebral disc is actually responsible for the nerve root irritation, the pain increases mainly depending on the load. Similarly, pressure increases in the abdominal cavity, for example through sneezing or coughing, lead to an increase in pain. In the case of a tumor, the pain tends to increase at rest.

In the same area where the pain occurs, sensitivity disorders such as tingling or numbness can occur. If the root damage is very severe, there is damage to the sensory nerve fibers as well as impairment of motor pathways. As a result, certain muscles responsible for lifting the foot and big toe and for spreading the leg can become weak.

Damage to motor fibers is always a warning sign and should be treated urgently, otherwise there is a risk of permanent nerve damage. The therapy of nerve root irritation at the level of the fifth lumbar vertebra depends on its cause. For example, a tumor usually requires surgical removal, while a herniated disc is usually treated purely conservatively, i.e. with physiotherapy and medication.

L4 syndrome

Root damage or irritation at the level of the fourth lumbar vertebra (L4) leads to characteristic symptoms, which are summarized as L4 syndrome. This syndrome is mainly characterized by pain in the front and middle part of the thigh, the front of the knee and the front and middle side of the lower leg. The most common cause of root damage here, as in other spinal column sections, is a herniated disc.

In many cases, whether this is actually the case can be seen in the clinical picture and the expression and localization of the symptoms. For example, in the case of a herniated disc, the pain increases under stress. Also an increase in pressure in the abdominal cavity, as it occurs with coughing, sneezing and the abdominal press, leads in this case to an increase in symptoms.

If a tumor were responsible for the root irritation, the pain would increase, especially at rest. In the areas of skin described above, in addition to pain, sensory disturbances such as tingling or numbness can also occur. If the nerve root irritation is correspondingly pronounced, impairment of motor nerve fibers can occur in addition to damage to sensory pathways.

This manifests itself in a weakness of the thigh muscles, as a result of which stretching in the knee is difficult or even impossible and pulling the thigh in the hip is also difficult. Likewise, the positioning of the corresponding thigh against the other is also impaired. Damage to motor fibers is always a warning sign and should be treated quickly to avoid permanent nerve damage.

The therapy of nerve root irritation at the level of the fifth lumbar vertebra depends on its cause. For example, a tumor requires surgical removal of the tumor, while a herniated disc is usually treated purely conservatively, i.e. with physiotherapy and medication. The nerve fibers originating from the spinal cord segment S1 at the level of the first sacral vertebra are involved in the formation of the sacral plexus, a network of nerves that is primarily responsible for supplying the gluteal and posterior thigh muscles.

If the nerve root is damaged at the level of S1, bending in the knee joint and stretching of the thigh in the hip are accordingly more difficult.Since the musculus triceps surae also supplies the calf muscles, walking on the tips of the toes is more difficult and the Achilles tendon reflex is weakened or even eliminated. Much more obvious for the patient and the treating physician, however, is the pain caused by the root damage. These radiate into the areas supplied by the first spinal nerve, which are mainly located on the back and side of the upper and lower leg and on the outer edge of the foot.

In the same areas of the skin, sensory disturbances such as tingling or numbness can also occur. The most common cause of nerve root irritation is also here the herniated disc. If a prolapse is actually responsible for the nerve root irritation, the pain will increase mainly depending on the load.

Likewise, sneezing and coughing and the application of an abdominal press lead to an increase in pain due to the resulting increase in pressure in the abdomen. In the case of a tumor, the symptoms of nerve root irritation increase, especially at rest. The treatment of spinal nerve root irritation at the level of the first sacral vertebra depends on its cause and can be conservative or surgical.