The anatomy of lower back pain


In Germany where I come from, more than half the time people take a sick day from work, it is because of debilitating back pain. And most other Western countries are no different. That is a crazy statistic to me, especially since back pain is something that can be fixed rather easily in most cases. It’s not a broken bone that has to be put back in place, it’s not an illness you have no control over. With diligence and patience, anyone can handle their back pain. When I say this, I mean the kind of back pain that results from muscle imbalances due to too much sitting, one sided movements (think of the shoulder you always sling your handbag over) or isolated muscle training. Of course there are "structural" problems with the spine such as scoliosis that cause back pain due to other forces at play.

When I work with new clients, lower back pain is usually on the top of their list. They think I am a magician for “curing” it, when I simply understand these anatomy principles I will outline here. Bear with me, this article may be a bit technically, but I really want you to understand the anatomy behind your own lower back pain. This is the best way for you to cure your lower back pain yourself. I have tried to keep technical terms to a minimum, grouping together muscles that you may have heard of and that are easier to remember, rather than mentioning something like “biceps femoris” instead of hamstrings :-).

So let’s dive right into the anatomy of your lower back pain.

Anatomy of lower back pain.jpg

When you look at the body, there are 4 specific landmarks in your hips that stand out:

1. Anterior Superior Iliac Spine (ASIS)

This sounds super fancy but basically means the bony part of your hip bones, that stand out (more or less) just underneath your waist in the front of your body on either side. These hip bones can be felt with your fingertips even if you can’t see them protruding when you are looking in the mirror. They are an attachment site for your abdominal muscles. Your abdominal muscles don’t need an introduction. Everyone has an idea where they are and what they give you - think bikini six pack.

2. Anterior Inferior Iliac Spine (AIIS)

The AIIS is much harder to pinpoint but if you take your hip bones and walk half way down towards the groin on that sexy line that men always want to train for, that is where the AIIS sits. This is the starting point of your quadriceps muscles, the front thigh muscles. They are often also referred to as hip flexors which tend to get extremely tight in people who do reversed sit ups wrong, they feel it in their hips rather than in their abs. Most people will have felt their quadriceps when they have sat on a leg extension machine at the gym.

3. Sacrum

The sacrum is a triangular bone which sits at the bottom of your spine. It is made up of 5 vertebras fused together, which makes this area hard and not very bendable. The end of the sacrum is the tailbone, the bottom tip of your spine, which I often refer to in my Pilates classes. If you fall on your sacrum, it is extremely painful as it doesn’t give way. The sacrum is a fancy way of saying just above your butt crack.

The sacrum is the attachment point for a group of muscles, which I will just refer to as your lower back muscles. What is important to know about your back muscles is that there are long ones, which run the entire length of the spine from the head to the sacrum, and there are smaller muscles connecting each of the vertebras. All of them are important to keep your spine upright and make it able to bend into all directions (forwards, sidewards, backwards), as well rotate around itself.

4. Ischiol Tuberosity

A funny name for what is basically your two sitting bones. You may be able to feel them if you grab your buttocks cheeks from behind. The sitting bones are attachment sites for your hamstrings, the muscles at the back of the thighs. Most people will know them from the hamstring curl machine at the gym.

How does lower back pain happen?

In an ideal world, these 4 points are always perfectly aligned with all 4 muscle groups equally strong to keep everything in check. When you are standing tall you have a light curve in your lower back and your tailbone will be pointing just slightly behind you to the floor.

Now let’s see what happens when you throw this system out of balance. Imagine connecting the 4 spots in the graph above into a rectangular box. Here are some scenarios that are extremely common and cause lower back pain to happen:

  • My clients love to train their abdominals. In fact, if I would let them, we would be doing sit ups for an entire hour because they believe this will give them flat abs. The lower back is not so “sexy” to train, because you don’t see it when you look in the mirror, but those abs are always staring at you. If these are overtrained and too tight, they will start to pull the ASIS point up towards your nose. What happens to your box? The top right corner gets pulled up, with the top left corner (sacrum) dropping down, stretching into your lower back and lengthening the back muscles. In that lengthened state, the lower back muscles are no longer able to support your spine in a strong way, thus lower back pain is created.

  • The quadriceps, also sitting in the front of your body, is another muscle group that is often overtrained and too strong compared to other muscles around the hips. If the quadriceps start to pull down the bottom right corner of your box, the box starts to tilt. Your belly basically starts to pop out like a pot bellied big, and your lower back is extremely arched. Bang! Another reason for lower back pain right here. Your spine is supposed to be in a natural S-shape curve. Straightening it out too much like in the first scenario with the abdominals or curving it too much like in the case of the quadriceps will result in an unnatural position for the muscles of the lower back, thus creating lower back pain.

  • The worst is when we have muscles that are weak and tight. This happens from our modern lifestyle of sitting too much at work, in front of a computer or watching TV. When we are sitting, all 4 muscle groups have a potential of becoming weak and tight:

  • The top of the quadriceps constantly gets shortened when we are sitting on a chair with our legs bend at 90º at the hips and knees. Even though the rest of the quadriceps (towards the knee) may be quite strong, this top part at the hip is often weak and tight. Most people will feel this when I ask them to move into some form of split or runner’s lunge.

  • While you are sitting on your butt at work, the hamstrings are constantly lengthened in this state, never being able to contract. They are weak in this position and tired from all the sitting = tight. Most people will feel these just lying on the back, bringing the leg up to the ceiling for a simple hamstring stretch. It’s tight and painful.

  • Your lower back starts to give away after hours of sitting as it is not normal to stay in this seated position for too long. Over time you will feel your spine collapse forward into a rounded back. This will also lengthen the lower back muscles, tugging on them all the time. They try to react by tightening, trying to make you sit upright again but you are still slouched over. They are in this constant battle of being overstretched but tightening at the same time = tight and lengthened. When sitting in a child’s pose on the heels, most people will start to feel a stretching and tugging at the lower back.

  • Lastly, as you are collapsing forward over your keyboard, you are squashing your abdominal muscles. They will no longer be strong and hold you up, but they will start to get shorter, weaker, and tighter. Your natural spine position will start to become a slouched over one over time. Anytime we arch the back into a back bend like a small cobra move, most people struggle with this in the beginning when the abs are too tight.

When we have tight and weak muscles, we have created a recipe for pain - not just lower back pain starts this way, but common knee and shoulder pain have the exact same principles behind them. This is why it is important to train from a holistic approach and not just with isolated exercises. Yes, abs look sexy and you may be able to do 1000 sit ups, but you are brining the rest of your equilibrium out of balance, causing more problems down the road.

To work yourself out of lower back pain, you want exercises that strengthen and stretch all 4 of these muscle groups, for example:

  • plank: the best exercise to target both abdominals (especially the lower lying ones that are really there for support and not just for a beautiful six pack) and your lower back muscles, without crunching uncomfortably into these muscles. 1 minute a day will start to help.

  • squats and lunges: done the right way, squats and lunges fire up your hamstrings, quadriceps, as well as use your lower back and abdominal muscles for stabilizing. They are the best way to strengthen and lengthen these muscles at the same time.

Here is why I personally love Pilates and yoga: when taught with an eye on the details of your anatomy, they are a great way to strengthen and lengthen these muscles, so you never have to suffer from lower back pain again. When you find yourself stuck with lower back pain and don't know how to get yourself out of it, I highly suggest you find a class with an instructor you trust. The instructor should pay plenty of personal attention to your pain and needs in order to help you back on track.

Here is to a healthier lower back!


#injuries #fitnesstips #anatomy #alignment #healthtips #Pilates #yoga