L4-L5 canal stenosis affects the lower lumbar area of the spine. This intervertebral space is prone to degeneration because it is at the end of the lumber spine and supports a significant part of the body’s weight. Knowing what L4-L5 canal stenosis is and how it can affect your health is important, because it can prematurely worsen your quality of life.
The spine has 33 vertebrae stacked on top of each other. Depending on the location, the vertebrae provide varying degrees of weight-bearing and flexibility in the spine. The lumbar spine, or lower back, consists of 5 vertebrae: L1, L2, L3, L4, and L5.
Lumbar canal stenosis refers to the narrowing of the lumbar vertebral canal through which the nerve roots travel to the legs. This narrowing can occur at one or more lumbar levels, with the L4-L5 space being the most often affected. The other levels can also be compromised, in the following order of frequency: L3-L4, L2-L3, L5-S1 and L1-L2.
What is L4-L5 canal stenosis?
As mentioned in the preceding paragraph, lumbar canal stenosis compresses the nerves that travel through the lower back to the legs. Because it is a degenerative condition, it affects older patients more often, but it can also affect younger patients.
Narrowing of the spinal canal usually occurs slowly, over years or decades. The intervertebral discs become less spongy with aging, which causes them to lose height, and the disc material can escape, bulging into the spinal canal. Bone spurs may also appear and ligaments may thicken, also contributing to stenosis. Symptoms of canal stenosis are due to inflammation, nerve compression, or both.
From age 30 and onwards, both the vertebrae and the intervertebral discs begin to suffer damage from wear and tear, and this is when degenerative spine disease can begin to appear. Find out more about degenerative diseases of the spine in this article:
Degenerative diseases of the spine
L4-L5 vertebrae
The L4-L5 vertebral segment consists of the two lowest vertebrae of the lumbar spine. It provides the ability to move in many directions and supports the upper torso.
The L4-L5 vertebrae are very flexible and are heavily impacted by our daily movements. This makes them particularly susceptible to injuries and chronic conditions, including canal stenosis or lumbar disc herniation.
While some patients may have L4-L5 canal stenosis without symptoms, the condition can affect the nerves and even lead to symptoms of sciatica.
Sciatica is a symptom of nerve root compression. It usually starts from the lower back, passes through the buttocks and travels down the back of the legs, producing a burning sensation or sharp, shooting jolts of pain. If there is significant compression of the nerve root, the patient may also feel muscle weakness in the leg, numbness, a constant sensation of tingling and/or pins and needles in the area of the leg innervated by that root.
Dr. Clavel, neurosurgeon and Director of Instituto Clavel, explains in “Alimente” what signs may indicate a case of sciatica that we should have checked by a doctor:
Primary symptoms of L4-L5 canal stenosis
Some of the most common symptoms of patients with this condition are:
- Loss of strength in the legs. Fatigue.
- Pain that runs down the back of the leg or, sometimes, the front of the thigh.
- Tingling, numbness, or prolonged pins and needles sensation.
- Gait claudication: this refers to pain, cramp or sense of fatigue in the legs when walking, that stops when the patient leans their trunk forward (the lumbar canal is opened and compression is relieved, therefore the symptoms usually disappear).
- If there is severe compression of the nerve roots that make up the cauda equina, there may be loss of bowel or bladder control.
Diagnosis of L4-L5 canal stenosis
To correctly diagnose lumbar canal stenosis, in addition to having some of the symptoms described above, the doctor will require imagining tests:
- Lumbar X-rays: (Antero-posterior, lateral and flexo-extension). This helps determine if there is any transition anomaly, displacement of vertebrae, signs of instability and/ or degree of lumbar lordosis.
- Lumbar MRI: Gives information about the soft structures of the spine, such as the yellow ligament, intervertebral discs, joint capsule, and nerve roots.
- Lumbar CT scan: Provides good resolution and definition of bone structures to determine the presence of bone spurs (osteophytes), the bone quality of the vertebrae, and the diameter of the lumbar canal.
Treatment for L4-L5 canal stenosis
In most cases, doctors recommend beginning with conservative treatment. When the condition is diagnosed and treated early enough, many patients can recover and spinal surgery is not necessary.
The most common conventional treatments for this condition are: physical therapy, with strengthening and flexibility exercises, mobilization and stabilization of joints, reinforcement of the core and lower limbs. Non-prescription or prescription medications to relieve pain may also be used; and manual physical therapy sessions, to release contractures, stiffness, or lack of elasticity.
At IC Rehabilitation our multidisciplinary team includes physical therapists, osteopaths, experts in active therapies, nurses, and neurosurgeons, who will help you improve and recover your quality of life with a personalized treatment.
If conservative treatments do not prove effective, there are pain clinic treatments: infiltrations, which can be epidural, transforaminal, or through the sacral hiatus. If there is significant facet joint degeneration and an important component of low back pain, treatment can also be performed with radiofrequency.
When neither conservative treatment options or pain clinic treatments are successful, and the patient’s pain restricts their ability to go about their normal activities, then surgical treatment for canal stenosis is needed. The main goal of this surgery is to decompress the area of the spinal cord and/or the nerve roots.
Generally, surgeons use two surgical techniques for the canal stenosis operation: either decompression, or decompression and stabilization.
If the goal is only decompression, a decompressive laminectomy can be performed, which can be carried out in 3 ways:
- Classic microscopic decompression
- Endoscopic decompression
- Tubular microscopic decompression
If the patient’s stenosis is affected by multiple contributing components, such as a herniated disc and hypertrophy of facet joints and/or yellow ligament, then aggressive decompressions will be needed, in which case the destabilization caused by surgery will mean that arthrodesis surgery will be required as well; that is, lumbar fusion with the placement of interbody titanium cages, screws and bars.
At Instituto Clavel, our philosophy is to always use the most minimally-invasive techniques suitable for the patient, so whenever possible, we try to use only decompression surgery, reserving fusion (arthrodesis) only for cases where it is strictly necessary.
If you want to know more about each of these techniques, and the recovery and risks of canal stenosis surgery, you can find out more in this article:
At Instituto Clavel we are always available to answer your questions. Don’t hesitate to contact us if you have any of the symptoms of lumbar stenosis described above. Our team will attend you and examine you as necessary to determine the condition of your spine.
Categories: Spine treatments, Spine pathologies, Lumbar pain