Understanding the function of your spine will help you understand how your posture and movement affect your back’s health. Anatomy basics can help you identify the root cause of your back pain. Your spine is made up of all of your body parts. They are yours for the rest of your life. Get to know them better.
Understanding anatomy will help you understand why diagnosing the cause of your back pain is more an art than science. Yes, there are many tests and protocols that health professionals can use. Why are they poking you with a pin, though? They are asking about your bowels and private parts. Soon you’ll find out.
A better understanding of your body will allow you to provide preventative care and rehabilitation. It will also help you communicate more effectively with healthcare professionals. Spend some time learning about your body. It will be time well spent. Just think about the conversation starters that you could use at your next cocktail party.
Bony Parts
Bones are complex, efficient bundles of tissue, water, and minerals. They do more than just provide a skeletal framework. They provide protection for vital organs like the heart, brain, and spinal cord, as well as scaffolding to which muscles can attach.
Multitasking is a great way to be productive! Bones are connected by ligaments and move through muscles. They can support a lot of weight without being broken or crushed (at least until there is trauma or a disease).
Bones can be described as living, breathing structures. Although they don’t inhale or exhale, bones can make red (and/or white) blood cells. Oxygen is delivered by red cells, while the white blood cells fight germs and diseases like soldiers.
A broken bone wouldn’t be broken forever if it weren’t for the fact that bones are alive. They are capable of surprisingly healing themselves, often with the help of our medical friends. The natural ability to self-repair a broken finger is just as valid for a fractured backbone.
We are born with approximately 300 bones. As we grow, some bones fuse together, including the vertebrae below the spine, called the sacrum or tailbone. Your vertebral ends, whether you’re a cat or a dog, would create a tail that can wag happily and lift wine glasses from a coffee table. The average adult skeleton has 206 bones and takes 20 years to reach maturity.
There are many sizes and shapes of bones, each designed to perform a specific function. The vertebrae are the bones that make up the spine. They look like building blocks. The vertebrae are like tiny cans that stack on top of one another. They are separated by small cushions called “discs.” They stack on top of each other like small cans, separated by little cushions called “discs.”
The Vertebral Column
Your spinal column, also known as your backbone or the spine, is a multipurpose, strong structure that can be used for many purposes. It supports your head and torso weight and allows you freedom of movement. It would be a rigid, rigid rod so that we’d walk like the robots in bad B-movies if it was. The flexible spine, supported and moved by muscles, allows us to bend and tie our shoes and twist and hit a ball of golf.
Your spinal cord is protected by the bony spinal column. It acts in a similar way to an electrical cord. It protects your spinal cord, which is a bundle of nerves that runs from your brain through the spinal column and branches out to the rest.
The spinal column is actually composed of 34 bones. Twenty-four bones make up the articulated vertebrae bones. A single bone is a vertebra. The remaining bones are located at the base of the spinal column, the naturally fused vertebrae from the sacrum (discussed in this article) and coccyx (discussed further in this article). These bones join your pelvis (hip bone). The spine is the group of 24 vertebrae that make up an elegant, double-S-shaped line.
The vertebral bones are different in size and shape, and get larger as they go down the column. There are many similarities, as well as differences. Each vertebra is made up of a large, cylindrical-shaped body with a vertebral arch.
You can further subdivide the arch into the spinous process (the bone you feel sticking out) or facet joints, which wing out to each side. A vertebra is a huge head that looks like three parts sticking out and one hole in its middle. Muscles, ligaments, and discs attach to various parts of the vertebra.
Your spinal cord is located in the space between your vertebral body (or arch) and the spinal canal. This canal can narrow due to disease or injury, and it can cause back pain. Your spinal cord is made up of many nerves, and these nerves transmit back pain signals.
There are also other openings between the stacked vertebrae. Intervertebral foramina, also known as spaces between the stacked vertebrae, are where nerve roots branch from the spinal cord.
Let’s look at the entire spinal column. The four main areas of the spine are referred to by health-care professionals as the cervical, thoracic, and lumbar. Each bone in an area has its own number. The spine curves naturally.
These curves strengthen the spine, absorb shock from running or jumping, and help maintain balance. Individuals will have different curve sizes, but too many can lead to problems.
Cervical spine: This section of your neck is made up of seven vertebrae (C1 to C7).The most prominent bone, C7, is the last. It is located at the base of your neck. This bone can be felt when you tilt your head forward. Try it.
Your head is the main function of the cervical vertebrae. The head can weigh up to 11 pounds, so this is no easy feat. This is why it’s so important to hold your head correctly. A small, but consistent forward tilt of your head is common for computer workers.
This can send forces deep into your neck and shoulders. The result? Nerve pinching can occur when your neck muscles are stressed. What was the result? Oh, no! You may feel back pain radiating from your neck to your arms.
Consider how many directions your head can go. There are up, down, and sideways, as well as forward, back, and around. It can also tilt like a bobblehead. For all these amazing movements, we can thank the cervical vertebrae and, in particular, the pivoting action of C1!
Most of the time, that’s a good thing. The downside is that the neck’s flexibility makes it vulnerable to injury, such as whiplash, if your head is thrust forward by an impact from a rear-end car crash.
The thoracic spine is located in your midback/rib-cage and has 12 vertebrae (T1–12). These attach to your ribs, unlike other vertebrae. Although the thoracic spine can move forward fairly easily, it is much more restricted in its ability to bend backward.
Back pain is usually not a problem in this area of the back. Most problems are located in the lower back. Kyphosis is a condition that causes the midback to curve in certain people. Bad posture is a common cause. Think of teenagers who slouch. It can also be caused by disease. The excessive curve can make a person look hunched-back, regardless of the cause.
Postural kyphosis can cause some discomfort due to disease. However, it is not usually a major problem. Excessively rounding your thoracic spine can cause your head to be positioned forward. This, as we have already mentioned, can lead to problems in your neck.
Forward slumping can also reduce the length of the muscles in your front and back, as well as overstretch some back muscles. This can cause discomfort when you sit straight up. This can be corrected with proper posture and exercise.
Lumbar spine: This is the most painful region. Before you curse that you were born with it (L1-L5), you should know that the five lumbar vertebrae (L1-L5) have a very important job: they support the majority of your body’s weight.
The largest vertebrae are the most qualified. These bones can be used for running, walking, sitting, lifting, and other activities. You can decrease the risk of injury by strengthening your abdominal muscles and ensuring your spine is flexible.
Muscle conditioning can support your lower back and other areas of the spine. Proper stretching can also help to keep this area flexible.
Lordosis is also known as “swayback,” and it’s a severe curve in your lower back. This curve places too much pressure on the lumbar vertebrae. Lordosis can result from disease, movement of the spine, bad posture, or bending the back. When gymnasts dismount from the parallel bars, they think about their final position.
The chest is pushed forward, the shoulders are back, and your lower back arches. This is how extreme lordosis of the lower back might look. Gymnasts are trained to do this. While it isn’t a cause of disease, gymnasts can develop back problems from performing these contortions.
For most of us mortals, just sitting incorrectly can put too much pressure on our lumbar spines. Identifying how your vertebrae should align and taking the appropriate steps can help get relief for back pain.
Sacrum and the coccyx (or backbone): While you might believe that only surgeons can do spinal fusion, this is actually something nature does. If you are over 30 years of age, you have already experienced it.
The flat triangular bone between your hips is called the sacrum. It’s actually five fused vertebrae. The fusion doesn’t occur until you are around 25–30 years old. This is the last and lowest curve in your spine. This curve is called the lumbosacral curvature, and it helps to support your body weight.
The tail end of your spine is located below the sacrum, also known as the coccyx. The coccyx is made up of several fused vertebrae, usually 3-5. Coccydynia can be caused by injury to this area.
Facet joints are the contact points between vertebrae. There are three types of joints in each vertebra: top, bottom, and sides. These joints connect to each level of the spine, as well as the levels below. They function in the same way as your finger or knee joint. These bone-to-bone joints are connected by cartilage, which is soft tissue.
The joint capsules are located between the joints. The capsule contains a fluid called synovial fluid. The lubricating liquid is vital to prevent grinding because of the high amount of sliding at these joints.
The lubricating fluid also works well with cartilage. Facet joints, like other joints in your body, are susceptible to repetitive stress injuries as well as degenerative diseases like osteoarthritis. The joint capsule may burst and cause cysts that pinch nerves. However, most often, they flare up.
Joints
Your sacrum and pelvis are connected by the sacroiliac joints (SI). They connect to your iliac bones. Your iliac bones can be felt easily; they are the bones at the tops of your hips. Strong ligaments attach your sacrum to the hip bones and stabilize it.
Although some motion can be achieved through these joints, it is very limited. These joints can become looser during pregnancy, which can lead to instability later on in life.
The SI joint is often overlooked as a source of back pain. It can also be subject to the same conditions that can occur in other joints, like osteoarthritis. Keep in mind how much weight the lowest portion of your spine carries.
These joints can be affected by excess body weight or lifting injuries. Muscular weakness and imbalances can lead to joint pain due to the many muscles that attach to the sacrum and can cause misalignment of joints, or even back pain sources.
Shock-absorbing Discs
Between each vertebra are discs. They are tough on the outside and soft on the inside with a gel-like fluid. They are like car tires with thick gel on the sides. The rubber tire absorbs bumps by “giving” slightly when your car is driven over them.
Similar to this, discs change shape with the movement of the spine. As with many other structures, discs can serve multiple functions. They act as shock absorbers and connect and protect the vertebral bones. Without discs, bone would contact bone with every movement and eventually grind away.
You should also know that the shocks absorbed are typically small and not a problem in general, especially since these discs can be quite hard. However, they do have limits, just like tires. If the shock is too severe, then something must give. A tire will blow.
Our intervertebral disks can have their gel on the outside burst (causing a herniated or bulging disc) or the other side can protrude (a bulging or bulging disc). The discs can also dry up and become thinner due to age or disease.
Problems can arise in the outer or inner gel layer. It’s important to understand the differences and talk with your doctor about them.
The annulus fibrosus is the outer layer of the disc. The annulus fibrosus is the outer layer of the disc. It attaches to the vertebra above and beneath, but it also provides cushioning. Because the fibers are interwoven, they make strong connections. This outer layer can bulge if it is subjected to repeated stress. The result can be pain if the bulge presses on a nerve.
The nucleus pulposus, a gel-like center of the disc that absorbs shock, is known as the nucleus pulposus.
It provides lubrication. It is mostly water. It can become thinner and less shock-absorbing as we age. Although there is evidence to suggest that inversion therapy and lumbar traction may help discs rehydrate more quickly, the long-term effects have not been proven.
Stabilizers And Movers
The bones of the skull are the foundation of our bodies. In the previous section, we discussed the discs and joints that connect the bones.
All these pieces need to be secured together. These include ligaments, muscles, tendons, and all types of connective tissues. Each of these provides stability and mobility to a greater or lesser extent.
Ligaments
Ligaments act as the chief of security. Their job is to keep out suspicious activity and allow normal activity. The spinal ligaments also allow for some forward, backward, and side motion, but put on brakes to limit excessive movement that could cause injury.
Ligaments are fibrous, strong bands with some elasticity. The spinal column is secured from the front and the back by long ligaments. Smaller ligaments attach to the vertebrae and hold them together.
The anterior longitudinal ligament attaches to the front of the vertebrae, restricting our ability to bend backwards. The posterior longitudinal ligament runs along both the front and back of the vertebrae. The supraspinous ligament attaches at the tips of the spinous processes. These two things limit our ability to bend forward. It is possible to strain ligaments, which can lead to back pain.
Muscles
There are two types of muscles: involuntary and voluntary. These muscles allow us to move, but they can also be controlled by our brains. Exercise can make both types stronger and more resilient. We will be focusing on the voluntary muscles that support and move the spine. Back pain is often caused by a lack of flexibility and muscle strength.
The body has layers of muscles. Some muscles are deeper than others, while others are more superficial or just below the surface. Deeper muscles can be more stable, which helps to protect bones. Back problems can also be caused by the muscles of the hips, legs, and pelvis. However, we will discuss their role in the exercise section.
You may already have been told by your doctor that strong abdominal muscles are essential for a healthy back. They also help stabilize your entire torso. There are four types of abdominal muscles.
The transversus abdominis is the deepest. It wraps around your body like an elastic corset. If you hold your stomach and cough, these muscles will contract. You have two sets of “oblique” muscles on the sides of your body. The internal obliques are deeper than the external obliques, which are closer to the surface. Obliques allow you to turn and side bend.
The rectus abdominis is the final option. They are primarily designed to push you forward, such as crunches and sit-ups. While they can help to compress your deeper abdominal muscles, stabilizing your spine requires that you strengthen the transversus, internal obliques, and deepest ab muscles. Pilates exercises are a great way to strengthen your back and ab muscles.
Two muscles are deep within the body. One on each side is called the iliopsoas muscles or the psoas. These muscles are called hip and leg flexors. They lift the legs, such as when you walk upstairs or go upstairs.
The psoas allows you to bend forward and flex your hips when your legs are stationary. The psoas are helpful in stabilizing you when sitting. The psoas is one of the most powerful and largest muscles in your body. They attach to the inside-top and bottom of your thigh bones and extend from your lumbar vertebrae. Sitting for prolonged periods of time can shorten or constrict the psoas and can lead to back pain when standing.
The layers of spinal muscles are similar to your abs. The deepest connections between vertebrae to each other are the smallest. The interspinales muscles attach to your spinous processes at the deepest point.
Transversospinalis creates a chevron-like pattern at the back of your spine. It helps you side bend, twist, and back bend. Next is the erector spinae. This group’s main task is to bend the back, but they can also help with side bending. The erector spinae muscles are often responsible for muscle spasms in our backs.
The rhomboids are located between your shoulder blades. They can be used to realign your vertebrae through physical therapy or exercise. The latissmius dorsi are the large, wing-like muscles that run along your back.
These muscles are responsible for stabilizing your back and allowing you to do pull-ups. The trapezius muscles run from your neck to your midback and up to your shoulders. These muscles allow you to move your neck and lift your shoulder blades. These muscles can become tight and sore when we get stressed.
Communications Central
All nerves eventually connect to the brain. There are two main types of nerves: Sensory nerves transmit information like touch, temperature, and pain to the brain, spinal cord, and other parts of the body. Motor nerves transmit signals from the brain into the muscles, which cause them to contract either reflexively or voluntarily.
The peripheral nervous system (PNS), which runs down the spinal canal, branches out into 31 pairs through openings called foraminae in the vertebrae. They transmit messages to and from your brain, or central nervous system, sending back pain signals and initiating motion–like “Hey, take off your hand from the stove! It’s hot! ” These nerves reflexively cause your spine to twist when you walk to maintain your balance. They keep you attached to your car seat when you turn corners at high speeds.
If you are curious, the cranial nerves in your skull supply the sense organs in your head and the muscles in your body.
The Spinal Cord
The spinal cord is a tube-shaped structure that contains a bundle of nerves and cerebrospinal liquid. It protects and nourishes the cord. The spinal cord is also protected by linings known as meninges and vertebral bone. The length of the spinal cord is approximately one inch at its widest point and 18 inches overall.
The spinal column is home to two pairs of nerves that branch out in a delicate web pattern throughout the body. Specific spinal nerves control each area of the body. It is quite logical. The cervical spine (neck area) has nerves that branch into your arms.
This is why back pain can radiate down your arms from a neck problem. The middle of your body is controlled by the nerves in your thoracic spine, while those in your lumbar spine control the outer legs. The sacral nerves control the middle and functions of the pelvis and the legs.
Nerves
As we have already mentioned, nerves that leave the spinal cord exit in pairs. One is sensory and the other is motor. It is not surprising to learn that motor nerves are responsible for bodily functions and movement. You can damage the motor nervous system.
You might be experiencing weakness or loss of function, such as loss of bladder control. However, if you don’t feel the pin in your foot, it could be a sign that you have lost sensation. This is because your sensory nerves control pressure, pain, temperature, and other sensations.
A doctor may gently poke your foot with a pin to check on your bowel movements. It could be a sign of nerve damage if you are unable to feel the pin or have trouble with your bowel movements.
Sometimes, a problem with a sensory nerve may feel like an electrical pain. Good athletic instructors will tell students to stop feeling this type of pain. This sensation can cause nerve damage, so it is best to stop doing any activity that causes it.
Cauda Equina
The spinal cord terminates in the lumbar spine. Here the nerves run in a bundle called the cauda Equina. This is so named because it looks like a horse’s tail.
These nerves provide sensory and motor function to the bladder, intestines, and legs. The immediate treatment of anyone suspecting that these nerves have been compressed is necessary.
That was easy! This concludes the anatomy article. It’s good that there isn’t a test. The back is made up of a complex network consisting of bone, muscles, and nerves. It can be difficult to determine what is wrong with your back when it hurts.
It could be something muscular, a compressed nerve or a misaligned vertebra. With a little knowledge, you will be able to appreciate the intricate nature of your back and be more prepared for visits to healthcare professionals.
Summary
- The spine is made up of a series of cylindrical bones called vertebrae. The spine is a collection of cylindrical bones called vertebrae that form a natural double S curve from your head to your hips.
- The SI joint is formed between the sacrum, tailbone, and hips. It can cause back pain and is often overlooked.
- Your spine is supported by your abdominal and back muscles.
- Your spinal column is connected to your brain via nerves that exit the body.
- Trauma or disease can cause nerve compression, which can lead to back pain or loss of limb or organ function.
- Stabilization and muscle movement are used to support the intricate vertebral bones.
- Intervertebral disks provide a cushion between the vertebrae and absorb shock from movement.
Sources:
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