Lumbar Spine Anatomy

Introduction

Physical Therapy in North Aurora, Batavia and Aurora for Lower Back

Welcome to Physical Therapy Advantage's patient resource about Lumbar Spine problems.

Knowing the main parts of your low back and how these parts work is important as you learn to care for your back problem.

Two common anatomic terms are useful as they relate to the low back. The term anterior refers to the front of the spine. The term posterior refers to the back of the spine. The section of the spine that makes up the low back is called the lumbar spine. The front of the low back is therefore called the anterior lumbar area. The back of the lower spine is called the posterior lumbar area.

This article gives a general overview of the anatomy of the low back. It should help you understand:

  • what parts make up the low back
  • how these parts work

Hear from some of our patients who we treated for Back Pain
Joe and his Team are fabulous, knowledgeable and friendly. I came to this practice following major spinal surgery, and I am so pleased with the care I received. I appreciate the level of expertise and...
Joe and his Team are fabulous, knowledgeable and friendly. I came to this practice following major spinal surgery, and I am so pleased with the care I received. I appreciate the level of expertise and care at a smaller independently owned clinic. I recommend Physical Therapy Advantage without reservation for your PT needs. Although Joe was my main provider, I had occasion two work with the two other PTs. Both were excellent! You won’t be disappointed if you give Physical Therapy Advantage a call for your needs. They will listen and provide you with excellent care that goes beyond your scheduled sessions. The front desk staff is courteous and respectful, too. This practice is professional, and I’m glad I followed a friend’s recommendation to give it a try!
Sara M
North Aurora, IL
After a painful back injury, PTA helped immensely in my recovery! I went from limited strength and range of motion to good as new in just a few weeks! I highly recommend them, and I would go back in a...
After a painful back injury, PTA helped immensely in my recovery! I went from limited strength and range of motion to good as new in just a few weeks! I highly recommend them, and I would go back in a heartbeat if/when I need help in the future!
Chris W
North Aurora, IL
Joe King and the staff at Physical Therapy Advantage are terrific. After two total hip replacements and spinal decompression surgery, I had been through several Physical Therapy experiences. My most...
Joe King and the staff at Physical Therapy Advantage are terrific. After two total hip replacements and spinal decompression surgery, I had been through several Physical Therapy experiences. My most recent surgery brought me to Joe and for the first time, I’m confident that Joe’s diagnosis and plan, will put me on the path to pain free independence. I’m grateful to have found Joe and his Team and give them my highest recommendation.
Mike G
North Aurora, IL
I am happy to recommend Physical Therapy Advantage! Joe and his team are competent, professional, and most importantly kind and caring. Joe is very thorough in his evaluation of you and creates a...
I am happy to recommend Physical Therapy Advantage! Joe and his team are competent, professional, and most importantly kind and caring. Joe is very thorough in his evaluation of you and creates a personalized routine to support your individual needs. He explains the proper techniques to you and watches to make sure you are doing the exercises correctly, offering suggestions if needed. He checks in with you to assess progress and answers any questions or concerns. I was very pleased with my progress working with Joe on some low back issues. I was able to resume activities I had stopped due to discomfort and feel confident that I have some new tools in my toolbox to help me in the future.
Eileen O
North Aurora, IL
Quality. Caring. Professional. Community driven. Physical Therapy Advantage stands as a shining star in the North Aurora area. I previously worked there as an aide and was blown away by the amount of...
Quality. Caring. Professional. Community driven. Physical Therapy Advantage stands as a shining star in the North Aurora area. I previously worked there as an aide and was blown away by the amount of care and professionalism Joe, Julie, and the Team carried themselves with. Years later I am now returning as a client for my shoulder and low back pain (I wouldn't think of going anywhere else). Julie has been able to relieve me of back pain that I had previously deemed as "something I will have to live with" as well as helped me with the numbness in my fingers. So yes, I would and have recommended Physical Therapy Advantage to anyone and everyone who needs it.
Andrew W
North Aurora, IL
I recently had back surgery to decompress a nerve that had been compressed for several years along with addressing some spinal stenosis issues.  Once things were sufficiently healed I started working...
I recently had back surgery to decompress a nerve that had been compressed for several years along with addressing some spinal stenosis issues.  Once things were sufficiently healed I started working with the folks at Physical Therapy Advantage.  They are an amazing group.  They listen to you, adjust their approach as-needed, pay attention to the whole picture, and give clear instruction.  I believe that working with them has helped me to heal faster, gain strength without reinjuring myself, and further improved the outcome of the sugery.  I would encourage anyone seeking the help of a physical thrapist to give Physical Therapy Advantage a call.
Teresa L
North Aurora, IL
Joe and his staff at Physical Therapy Advantage are fantastic. I’ve been a client twice and had a great experience both times.The first time was due to severe low back pain (with spinal arthritis...
Joe and his staff at Physical Therapy Advantage are fantastic. I’ve been a client twice and had a great experience both times.The first time was due to severe low back pain (with spinal arthritis and a herniated disc as the primary causes) about five years ago. It had gotten bad enough that I was barely able to crawl, let alone stand up or walk. I saw my primary care doctor and a neurosurgeon and had an epidural steroid injection for the pain before being prescribed physical therapy to see if it helped. It did! Joe was able to figure out what was out of alignment and why, and I was pain-free in a just a few months.I recently had some pain again in my hip and low back and decided to skip the shots and doctor visits and just head straight to physical therapy. I went back to Physical Therapy Advantage since my experience the first time was so good. The second time was just as good - I’m all fixed up just a few months later and have a home stretching and exercise routine to prevent future problems (which I’m about to do after posting this!).Joe is great at diagnosing and explaining exactly what is wrong and how the exercises and stretches he recommends will work to fix it. He and his staff are also positive and friendly. I hope that I won’t have a need for more physical therapy any time soon, but if I ever do, I’ll be seeing Joe again.
Eric B
North Aurora, IL
Great experience overall. I went in with lower back nerve pain hoping to find relief knowing that complete and and total relief is not possible. Through targeted stretching to loosen the joints and...
Great experience overall. I went in with lower back nerve pain hoping to find relief knowing that complete and and total relief is not possible. Through targeted stretching to loosen the joints and muscles involved and exercises design to strength and stabilize the joints and muscles involved, I did find good comprehensive relief for the nerve pain. Joe also provided a good workout plan to maintain the flexibility and strength going forward on my own, it was exactly what I needed.
Daniel T
North Aurora, IL
Joe King and his team are top notch. They are experts at listening and evaluating your area of need. In my case it's knee and hip issues. I walk in with pain in my knee, hip or back and after...
Joe King and his team are top notch. They are experts at listening and evaluating your area of need. In my case it's knee and hip issues. I walk in with pain in my knee, hip or back and after several appointments, I walk out pain free. For me it's muscle tissue massage along with completing the exercises they recommend. I've always had great results with Physical Therapy Advantage and wouldn't consider going anywhere else.
Mike S
North Aurora, IL
Joe, Julie and entire staff was very professional courteous and exceeded my expectations for my recovery of a herniated disk. They were always concerned about my pain level and discomfort. I would...
Joe, Julie and entire staff was very professional courteous and exceeded my expectations for my recovery of a herniated disk. They were always concerned about my pain level and discomfort. I would recommend Physical Therapy Advantage to any one who needs PT. They are the gold standard.
Gary S
North Aurora, IL
As compared to other physical therapists and their regimen, I rate PTA superior in every respect. The initial evaluation was thorough and informative. But most important was the protocol for each...
As compared to other physical therapists and their regimen, I rate PTA superior in every respect. The initial evaluation was thorough and informative. But most important was the protocol for each visit beginning with a 30 minute manipulation/massage performed by Joe or Julie followed by 30 minutes of exercises....varying from visit to visit...specifically selected for my current condition and supervised by an aspiring PT assistant qualified to do so. Can't say enough positive about a team that has helped me through back, knee and leg therapies.
DeAnne Z
North Aurora, IL
I have been in and out of physical therapy going on 10 years now dealing with a combination of inherited genetic spine/joint disorders and arthritic issues. Joe King and his staff have provided me...
I have been in and out of physical therapy going on 10 years now dealing with a combination of inherited genetic spine/joint disorders and arthritic issues. Joe King and his staff have provided me all these years with exceptional care and quality service. From the in-depth initial evaluation to create a specific personal care plan to each appointment where I am given the opportunity to ask questions, express concerns and discuss my at home progress. Joe and his team listens intently, provides feedback and welcomes input in order to work together with the client as a team to come up with the most beneficial long term plan for the client to help ensure success once they are released from therapy and on their own at home. Such quality care is rare today but you will find it here at Physical Therapy Advantage!
Michelle D
North Aurora, IL
A few years ago, a reputable doctor out of Elmhurst recommend Physical Therapy Advantage (specifically Joe the owner) when I needed physical therapy for my lower back. I’m glad I did therapy...
A few years ago, a reputable doctor out of Elmhurst recommend Physical Therapy Advantage (specifically Joe the owner) when I needed physical therapy for my lower back. I’m glad I did therapy instead of going with the surgical option offered to me at the time. I wouldn’t go to anyone else for physical therapy. I’ve since seen Joe for other physical ailments, which tend to pop up as we age, and I’ve been very happy with those results as well. Joe is extremely knowledgeable and professional and it’s nice to know he’s just around the corner if needed.
CCS B
North Aurora, IL
I've had a lower back problem for many years and because of it I've been going to several physical therapy places trying to find some relief. Only when I came to Physical Therapist Advantage I felt...
I've had a lower back problem for many years and because of it I've been going to several physical therapy places trying to find some relief. Only when I came to Physical Therapist Advantage I felt that I finally found the right place. Joe King was the only one to take the time to explain in details why I was having so much pain and what he was planning to do about it. Even though it's not part of my network, I am still going to continue his therapy because I am confident it will help me find the solution to my long and painful situation. Thank you Joe!
Catia M
North Aurora, IL
It was my good fortune to have a friend recommend me to Physical Therapy Advantage after a back injury in the fall of 2012. Word of mouth has always been my preferred way to find a health care...
It was my good fortune to have a friend recommend me to Physical Therapy Advantage after a back injury in the fall of 2012. Word of mouth has always been my preferred way to find a health care provider. Joe King and his associates at Physical Therapy Advantage were always concerned, supportive, encouraging, and professional. By truly listening to my problems and issues, Joe crafted a treatment plan for me that oincluded in-clinic care as well as home exercises to support that care. The results were so positive, that I did not hesitate to return to this clinic when I found out in 2013 that I needed knee replacement surgery. Again, a therapy plan was created for me prior to surgery in June 2014, and then after surgery to enable me to get my new knee strong, and to increase my flexibility when moving it. Once more, after much dedicated care by Joe and exercise work by me, the results were positive. However, osteoarthritis was not done with me yet! In late 2014, I found that I needed both of my hips replaced as well. This was very discouraging news. However, I had such confidence in my surgeon, as well as in my physical therapist, Joe and the staff at Physical Therapy Advantage, I knew that I could face these surgeries and rehabs. Throughout this entire time, I could always count on Joe and his staff to keep me positive and focused on the end result-- to walk without pain! After left hip surgery in Feb. 2015, and then right hip surgery in June of 2015, their subsequent physical therapy sessions and home care exercises, I finally reached my end goal---to walk without pain! It was a hard, 3 yr. long, physically taxing journey but, with the professional care I received from this facility, with all their support and encouragement, I was successful. I highly recommend Joe King and Physical Therapy in North Aurora.
Jan M
North Aurora, IL
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Important Structures

The important parts of the lumbar spine include:

  • bones and joints
  • nerves
  • connective tissues
  • muscles
  • spinal segments

This section highlights important structures in each category.

Bones and Joints

The human spine is made up of 24 spinal bones, called vertebrae. Vertebrae are stacked on top of one another to form the spinal column. The spinal column is the body's main upright support.

From the side, the spine forms three curves. The neck, called the cervical spine, curves slightly inward. The middle back, or thoracic spine, curves outward. The outward curve of the thoracic spine is called kyphosis. The low back, also called the lumbar spine, curves slightly inward. An inward curve of the spine is called lordosis.

Three Curves in Spine


The lumbar spine is made up of the lower five vertebrae. Doctors often refer to these vertebrae as L1 to L5. The lowest vertebra of the lumbar spine, L5, connects to the top of the sacrum, a triangular bone at the base of the spine that fits between the two pelvic bones. Some people have an extra, or sixth, lumbar vertebra. This condition doesn't usually cause any particular problems.

Lower Vertebrae

Each vertebra is formed by a round block of bone, called a vertebral body. The lumbar vertebral bodies are taller and bulkier compared to the rest of the spine. This is partly because the low back has to withstand pressure from body weight and from movements such as lifting, carrying, and twisting. Also, large and powerful muscles attaching on or near the lumbar spine place extra force on the lumbar vertebral bodies.

A bony ring attaches to the back of each vertebral body. This ring has two parts. Two pedicle bones connect directly to the back of the vertebral body. Two lamina bones join the pedicles to complete the ring. The lamina bones form the outer rim of the bony ring. When the vertebrae are stacked on top of each other, the bony rings form a hollow tube that surrounds the
spinal cord and nerves. The laminae provide a protective roof over these nerve tissues.

Bony Ring

A bony knob projects out at the point where the two lamina bones join together at the back of the spine. These projections, called spinous processes, can be felt as you rub your fingers up and down the back of your spine. Each vertebra also has two bony knobs that point out to the side, one on the left and one on the right. These bony projections are called transverse processes. The projections in the low back are broader than in other areas of the spine because many large back muscles attach and impart powerful forces on them.

Between the vertebrae of each spinal segment are two facet joints. The facet joints are located on the back of the spinal column. There are two facet joints between each pair of vertebrae, one on each side of the spine. A facet joint is made of small, bony knobs that line up along the back of the spine. Where these knobs meet, they form a joint that connects the two vertebrae. The alignment of the facet joints of the lumbar spine allows freedom of movement as you bend forward and back.

Facet Joints

The surfaces of the facet joints are covered by articular cartilage. Articular cartilage is a smooth, rubbery material that covers the ends of most joints. It allows the ends of bones to move against each other smoothly, without friction.

Articular Cartilage

On the left and right side of each vertebra is a small tunnel called a neural foramen. (Foramina is the plural term.) The two nerves that leave the spine at each vertebra go through the foramina, one on the left and one on the right. The intervertebral disc (described later) sits directly in front of the opening. A bulged or herniated disc can narrow the opening and put pressure on the nerve. A facet joint sits in back of the foramen. Bone spurs that form on the facet joint can project into the tunnel, narrowing the hole and pinching the nerve.

Neural Foramen

Nerves

The hollow tube formed by the bony rings on the back of the spinal column surrounds the spinal cord. The spinal cord is like a long wire made up of millions of nerve fibers. Just as the skull protects the brain, the bones of the spinal column protect the spinal cord.

Spinal Cord

The spinal cord extends down to the L2 vertebra. Below this level, the spinal canal encloses a bundle of nerves that goes to the lower limbs and pelvic organs. The Latin term for this bundle of nerves is cauda equina, meaning horse's tail.

Between vertebrae, two large nerves branch off the spinal cord, one on the left and one on the right. The nerves pass through the neural foramina of each vertebra. These spinal nerves group together to form the main nerves that go to the organs and limbs. The nerves of the lumbar spine (cauda equina) go to the pelvic organs and lower limbs.

Connective Tissues

Connective tissues are networks of fiber that hold the cells of the body together. Ligaments are strong connective tissues that attach bones to other bones. Several long ligaments connect on the front and back sections of the vertebrae. The anterior longitudinal ligament runs lengthwise down the front of the vertebral bodies. Two other ligaments run full-length within the spinal canal. The posterior longitudinal ligament attaches on the back of the vertebral bodies. The ligamentum flavum is a long elastic band that connects to the front surface of the lamina bones (just behind the spinal cord). Thick ligaments also connect the bones of the lumbar spine to the sacrum (the bone below L5) and pelvis.

Ligaments

A special type of structure in the spine called an intervertebral disc is also made of connective tissue. The fibers of the disc are formed by special cells, called collagen cells. The fibers may be lined up like strands of nylon rope or crisscrossed like a net.

An intervertebral disc is made of two parts. The center, called the nucleus, is spongy. It provides most of the shock absorption in the spine. The nucleus is held in place by the annulus, a series of strong ligament rings surrounding it.

Two Parts of Intervertebral Disc

Muscles

The muscles of the low back are arranged in layers. Those closest to the skin's surface, the superficial layer, are covered by a thick tissue called fascia. The middle layer, called the erector spinae, has strap-shaped muscles that run up and down over the lower ribs, chest, and low back. They join in the lumbar spine to form a thick tendon that binds the bones of the low back, pelvis, and sacrum. The deepest layer of muscles attaches along the back surface of the spine bones, connecting the low back, pelvis, and sacrum. These deepest muscles coordinate their actions with the muscles of the abdomen to help hold the spine steady during activity.

Low Back Muscles

Spinal Segment

A good way to understand the anatomy of the lumbar spine is by looking at a spinal segment. Each spinal segment includes two vertebrae separated by an intervertebral disc, the nerves that leave the spinal column at each vertebra, and the small facet joints that link each level of the spinal column.

The intervertebral disc separates the two vertebral bodies of the spinal segment. The disc normally works like a shock absorber. It protects the spine against the daily pull of gravity. It also protects the spine during heavy activities that put strong force on the spine, such as jumping, running, and lifting.

The spinal segment is connected by two facet joints, described earlier. When the facet joints of the lumbar spine move together, they bend and turn the low back.

Summary

Many important parts make up the anatomy of the back. Understanding the regions and structures of the lumbar spine can help you be more involved in your health care and better able to care for your back problem.

Portions of this document copyright MMG, LLC.