What is numbness in the leg?
A numbness describes a reduced sensation of feeling. In clinical language this phenomenon is called hypaesthesia. The normal sensation that occurs when touching the leg, such as when stroking, no longer feels as strong as before.
Some people describe this numbness as if the leg is wrapped in absorbent cotton. If this numbness is very strong, it is also possible that the sensation is no longer present when you touch it. Numbness in the leg can be one-sided or two-sided, the whole leg can be affected or only certain areas of the leg. Some people know such a numbness in the leg from situations where the leg has fallen asleep.
Causes
Leg numbness usually occurs after damage, irritation or constriction of a nerve or damage to a nerve pathway that supplies the area of the leg or parts of the leg. Such damage can be caused by a herniated disc in the lumbar spine, by irritation of the sciatic nerve. In addition, numbness may be caused by constriction of a specific nerve that runs under the inguinal ligament or as a result of multiple sclerosis.
Other causes of reduced sensation in the leg can also be polyneuropathy or, if it occurs very suddenly, a stroke can also be responsible. There are many other causes of numbness in the leg. A slipped disc in the lumbar spine is an event that can occur as a result of incorrect loading in the lumbar spine.
In this case, the intervertebral disc, which is located between two vertebral bodies, is damaged and material from inside the disc can leak. This material can escape in the direction of the spinal canal in which the spinal cord runs. This can cause a narrowing or damage to the spinal cord or a nerve root at this location.
In the lumbar spine (lumbar spine for short), nerves run in particular, which supply the legs, but also the bladder and rectum. Depending on the nerve root in which the herniated disc is located, different areas of the leg can be affected. The nerve root L3 sensitively supplies an area that runs along the thigh from the top/outer to the inner area of the knee.
The nerve root L4 sensitively supplies an area that runs from the outer edge of the knee, over the front of the tibia to approximately the inner ankle. The outer side of the lower leg, sloping to the big toe, is supplied sensitively by the nerve root L5. The area of the nerve root S1 supplies an area that runs along the outer edge on the back of the leg to the sole of the foot and the outer area of the foot.
But a slipped disc can not only cause numbness. Depending on the area and severity of a herniated disc in the lumbar spine, symptoms such as paralysis, altered sensation of feeling, reduced sensation of pain, disturbances in bladder and bowel emptying and loss or reduction of reflexes can also occur. Sciatica is a large nerve (medical term: sciatic nerve) that runs through the buttocks and the back of the thigh until it splits into other nerves in the area of the knee (common fibular nerve and tibial nerve).
The main symptom of sciatica irritation or incarceration is usually pain in the course of the sciatic nerve and also in its branches. These run along the back of the thigh, the lower leg and the foot. However, numbness in the area of the nerve supply area or back pain can also occur.
Irritation of the sciatica can have various causes, it can occur, for example, as a result of a herniated disc, after operations in areas where the nerve runs or after inflammation. This term refers to the symptoms caused by constriction of a nerve in the leg. This nerve sensitively supplies the outer side of the thigh and is called the lateral cutaneus femoris nerve in medical terminology.
The nerve passes through a natural constriction in the body, an area below the inguinal ligament. If the nerve is additionally constricted by, for example, too tight pants, overweight or pregnancy, symptoms such as pain and sensation, which may also include numbness, can occur. In most cases, the pain is relieved by bending the hip joint.
MS is the short form for multiple sclerosis.This is a chronic disease of the nervous system, in which the nerve sheaths are destroyed, resulting in a long-term loss of function of these nerves. Symptoms can also include numbness in the leg, when nerve tracts are affected that supply the leg with sensitive nerve tissue. However, other symptoms of MS can also occur (such as paralysis or impaired vision).
However, the diagnosis of such a serious disease can only be made by a doctor in the field of neurology. Surgery for a herniated disc is usually only performed if there is a very pronounced herniated disc, e.g. if disorders of bladder and bowel emptying are present or if severe paralysis has occurred. During operations there are always possible complications that can occur.
When a herniated disc is operated on in the lumbar spine, the operation is performed very close to the spinal canal. Thus, after such an operation (the indication for which is carefully considered), irritation of a nerve root, among other things, can occur. Such irritations can be accompanied by pain or sensations such as numbness.
If you are about to undergo surgery, you will usually be informed in detail about the procedure and possible complications. If you have any concerns, you can always ask the attending physician questions. A thrombosis in the leg, medically called deep vein thrombosis, can have a wide variety of symptoms or none at all.
When symptoms occur, they often manifest themselves in the form of redness, swelling or overheating and pain in the affected leg. Where exactly on the leg these symptoms occur depends on the section of the leg where the thrombosis is located. Feelings of numbness in the leg during thrombosis are rarely described.
