What is neural foraminal stenosis ?
To understand neural foraminal stenosis, let us first understand a bit of spinal anatomy. The spinal column is formed of bones known as the vertebrae that are structured one upon another like a stack of blocks. There is a central canal that runs through the entire length of the vertebral column. The spinal cord descends through this canal. There are tiny holes present on each side of the canal from which spinal nerves emerges at each level of the spinal bone. These holes are known as neural foramen or a lateral foramen. Neural foraminal stenosis is characterized by the narrowing of these tiny spaces or holes which contain the nerve roots. This type of spinal stenosis is the most common of all types of stenosis. Moreover, the lowest lumbar level is affected in almost 70% of the cases.
Disc degeneration due to the natural aging process is the most common cause. Other causes include degenerative diseases such as osteoarthritis, rheumatoid arthritis and structural abnormalities.
Neural foraminal stenosis symptoms
The symptoms of this condition depend on the location of the narrowing. Since neural foraminal stenosis affects the lumbar area in majority of the cases, symptoms are frequently present in the lower extremities. Some of the common symptoms are:
In case sciatic nerve is affected, the symptoms of sciatica are produced. These are recurrent low back pain that radiates to the buttock and lower leg, numbness, tingling and weakness of the lower extremities. The symptoms are worse upon exertion to such an extent that walking becomes difficult.
Intermittent neurogenic claudication is manifested as leg pain, weakness and numbness on walking. The symptoms are relieved when the patient sits and rests for a few minutes.
The symptoms of neural foraminal stenosis develop and get worse gradually over a course of several years. The symptoms of leg pain and low back pain are worse after standing and walking and the more the duration of exertion is, the worse the symptoms become.
The symptoms also get worse by backward bending, sideways bending and on rotating. Forward flexion and sitting relieve the symptoms.
Symptoms also get worse by standing upright and are relieved by rest.
Neural foraminal stenosis treatment
Accurate diagnosis of neural foraminal stenosis is very important to treat the condition effectively. Imaging studies such as CT scan and MRI have become invaluable in the diagnosis.
Treatment depends upon the severity of the symptoms and the level of disability caused. The first approach in management is non-surgical that include exercise, activity modification, painkillers and epidural injections.
Non-surgical treatment: Neural foraminal stenosis often causes symptoms that may restrict a patient’s activities. The aim of non-surgical management is to relieve the symptoms, maintain the activity level of patients and prevent complete disability. These modalities do not cure the condition.
Exercises: An appropriate exercise program is recommended early on in the disease and should be done under the supervision of a trained physical therapist.
Activity modification: As symptoms are worse in certain positions, patients are advised to avoid such positions and attain positions that relieve their symptoms. Some examples of activity modification are: instead of walking upright, walking leaning forward on a walker, doing exercise on a stationary bike while bent over and avoiding walking and sitting in a recliner chair.
Painkillers: Anti-inflammatory medicines such as ibuprofen may be recommended to relieve the pain and inflammation.
Epidural injections: A steroid injection is given in the space between the outer and middle covering of the membrane covering the spinal cord. An epidural injection can temporarily relieve the pain of neural foraminal stenosis and the injections can be repeated over a course of few months.
Surgical treatment: Surgery is usually recommended in those patients in whom the activities of daily living are affected due to the symptoms of spinal stenosis. Before going for a spinal surgery certain important factors should be taken into consideration: the diagnosis and the location of the stenosis should be accurate, patient should be medically fit to tolerate general anesthesia, the surgeon should be capable of performing the surgery with minimal destruction of the normal tissues so that no additional problems such as nerve injury are created by the surgery.
There are two types of spinal decompression procedures: microdiscectomy and lumbar laminectomy. In both of these surgeries the affected region is opened up and the pressure released off the spinal nerves. The outcomes of a surgical decompression surgery are favorable and most of the patients are relieved of their symptoms and able to increase their activity level.
Spinal decompression surgery is combined with a spinal fusion to treat a neural foraminal narrowing. Spinal decompression in cases of neural foraminal stenosis leads to instability of the spine due to simultaneous removal of the bone spur and the facet joint. A spinal fusion becomes necessary to achieve stability in such cases.
Filed under: Spinal Stenosis