The lumbar spine is the lower section of the spinal column, located below the thoracic spine and above the sacrum. It is made up of five vertebrae, numbered L1 to L5. The lumbar vertebrae support the weight of the torso and provide stability to the lower back. They also protect the spinal cord, which extends from the upper portion of the body, through the lumbar region of the spine and into the sacrum.
Each lumbar vertebra has a body, spinous process, transverse processes, and facets that articulate with the vertebrae above and below. The body of the vertebra is the main weight-bearing portion and is separated from the next vertebra by an intervertebral disc. Intervertebral discs provide cushioning and shock absorption.
The spinous and transverse processes are bony projections that provide attachment points for muscles and ligaments. The facets are the joints that connect the vertebrae and allow for movement.
The lumbar spine is supported by muscles, ligaments and fascia that surround and connect the vertebrae. The anatomy of the lumbar spine and its soft tissue support allows for a wide range of movement, including flexion, extension, lateral bending, and rotation, which are essential for performing activities such as bending, lifting, and twisting.
Conditions That Affect The Lumbar Spine
Lumbar vertebrae are the largest and strongest vertebrae in the spine. The lumbar region of the spinal column is the only part of the skeleton that connects the upper and lower portions of the body and therefore the lumbar spine functions under a lot of strain and pressure. Conditions affecting this region are often degenerative, causing pain and limiting movement.
Degenerative Disc Disease
Degenerative disc disease is a condition that occurs when intervertebral discs wear down over time. The spinal discs are responsible for providing cushioning and shock absorption to the spine, and as they degenerate, they become less effective at performing these functions. This can lead to pain and stiffness in the lower back, nerve compression and associated symptoms like radiating pain, numbness, and weakness.
The body may respond to disc degeneration by producing bone spurs, which can narrow the space available for nerves to pass through and cause additional compression.
Intervertebral discs are made up of a soft centre surrounded by a tougher exterior casing. As discs experience wear and tear and general degeneration, the exterior portion may become thin or crack, allowing the soft centre of the disc to push through. Sometimes the resulting protrusion pushes on a nerve or vessel, causing pain, numbness, and weakness in the lower back, legs, and feet.
Spinal stenosis is when the spinal canal narrows, leading to compression of the spinal cord and nerves. This narrowing can occur in any part of the spine, but it is most common in the lumbar region. Nerve compression may lead to a variety of symptoms such as pain, numbness, tingling, and weakness in the lower back, legs, and feet.
Spinal stenosis can be caused by several factors, including degenerative changes to the spine, such as osteoarthritis, herniated discs, and bone spurs. Some people may develop spinal stenosis as a result of an injury or trauma to the spine or due to congenital conditions.
Spondylolisthesis is a condition that occurs when one vertebra in the spine slips out of its normal position and slides forward over the vertebra below it. It is most commonly found in the lumbar region of the spine. Spondylolisthesis can be caused by a variety of factors, including genetic predisposition, age-related wear and tear, or traumatic injury.
Symptoms of spondylolisthesis can vary depending on the severity of the condition. Some people experience no symptoms at all, while others experience lower back pain and stiffness, muscle spasms, leg pain, numbness or weakness in the legs, and difficulty walking or standing for extended periods.
Osteoarthritis, also known as degenerative arthritis, is a type of arthritis that affects the joints in the spine, causing the cartilage that cushions the joints to wear down over time. It is more common in older adults and can be caused by a variety of factors, including ageing, obesity, genetics, and previous injuries or trauma to the spine.
As the protective cartilage breaks down, bone-on-bone contact can cause stiffness and swelling in the affected area, making it difficult to move or bend. The pain can range from mild to severe and may be aggravated by activities such as sitting or standing for prolonged periods, lifting heavy objects, or twisting the spine.
The sciatic nerve is the longest in the body, running from the lower back down through the buttocks and legs. Sciatica is when the sciatic nerve is compressed. This can be caused by a variety of factors including a herniated disc, spinal stenosis, spondylolisthesis, or even pregnancy.
Sciatica can cause a range of symptoms including sharp or shooting pain, numbness, tingling, or weakness in the lower back, buttocks, legs, and feet.
Compression fractures are usually caused by trauma or osteoporosis. The vertebral body is the largest part of the vertebra and bears the most weight. It can collapse or become compressed due to increased pressure and bone weakness.
Compression can cause pain, stiffness, and loss of height in the spine. Compression fractures can also lead to other complications, such as spinal deformities and nerve damage.
Lumbar Spine Surgery
Treatment plans for conditions in the lumbar spine typically include a combination of medication, physical therapy, and lifestyle modifications to manage symptoms and improve overall bone and joint health. In some cases, surgery may be necessary to repair or replace damaged discs, vertebrae or joints.
A discectomy is a surgical procedure that involves removing the portion of a herniated disc that is exerting pressure on the spinal cord or nerve roots. This procedure can be performed either through an open incision or a minimally invasive technique, using an endoscope (a small tube with a camera at the end, and specialised tools).
The main objective of a discectomy is to alleviate pain, numbness, and weakness that may be caused by nerve or spinal cord compression. Discectomies are often employed to address conditions such as herniated discs, spinal stenosis, and degenerative disc disease.
The Lamina forms part of the vertebral canal through which the spinal cord runs, protecting and supporting the cord on its progress through the body. Should the vertebral canal become narrowed for any reason, a laminectomy may be performed to relieve pressure on the spinal cord or nerve roots.
The procedure involves removing parts of the lamina, to widen the spinal canal. A laminectomy may be performed either through open or minimally invasive surgery, depending on the location, the severity of the condition and the preference of the surgeon.
Spinal fusion involves permanently joining two or more vertebrae to form a solid bony structure that stabilizes the spine. The procedure involves placing bone grafts or artificial implants between vertebrae and bracing the area until the vertebrae have fused. This immobilises the joints between vertebrae and can help to alleviate pain caused by movement and degenerative conditions.
A foramen is a hole in the bone that allows nerves and vessels to pass. When a foramen narrows, it can compress the soft tissues passing through it. In the spine, intervertebral foramina allow for nerve roots from the spinal cord to pass through. A foraminotomy is a procedure to enlarge narrowed foramina in the spine.
A foraminotomy may be done using either open or minimally invasive surgery, depending on the severity of the condition, the location or the preference of the surgeon. Traditional open surgery includes a larger incision and more tissue manipulation to access the foramen. Minimally invasive surgery involves making a smaller incision and using specialised instruments and an endoscope to access the affected area with less tissue disruption.
Artificial Disc Replacement
Artificial disc replacement involves removing a damaged intervertebral disc and replacing it with an artificial disc implant. The artificial disc is designed to mimic the function of a natural spinal disc, allowing for a normal range of motion, flexibility and shock absorption in the spine and providing support to the surrounding vertebrae.
Artificial disc replacement is open surgery. The surgeon will make an incision in the patient's lower back to access the affected disc. The damaged disc is then carefully removed, and the artificial disc implant is inserted in its place.
Conditions that affect the lumbar spine are often a result of ageing and overuse. Spinal conditions can cause significant pain and discomfort, limiting the individual's movement and quality of life. Treatment plans including lumbar spine surgery will be tailored to the individual needs of the patient and are often aimed at repairing or replacing damaged parts of the lumbar spine and its associated intervertebral discs. Surgery will be accompanied by non-surgical treatments to aid in stabilisation and healing.