Lower back pain is a very common ailment affecting far too many of us. In fact, the World Health Organisation puts the incidence of lower back pain at 80%.
Lower back pain has many causes for its occurrence. These causes include disease processes (like rheumatoid arthritis ), infections (sometimes TB can cause lower back pain), injuries (like a fall down the stairs or a car accident), genetic predispositions (like spondylolysis) and then you get mechanical factors (like poor lifting technique and poor exercise habits amongst a whole host of others).
One common mechanical aggravating factor for lower back pain is when a person suffers from tight hamstrings. To understand more about how your tight hamstrings will contribute to your lower back pain, we need to first understand more about the hamstrings.
Let’s start with where the hamstrings are found in our body. Where do the hamstrings start and end in the body? The hamstrings attach to the bottom of your pelvis and end just below your knee. Because the hamstrings attach to the pelvis and to the tibia (the shin bone), when the hamstring contracts, it will affect both the hip joint and the knee joint. We call it a 2 joint muscle. 2 joint muscles typically are important in controlling movement in the body.
Thus, the hamstring muscle is responsible for helping to pull the hip backwards and to bend the knee, and we use these hip and knee movements throughout the day, for example when we walk. The hamstring also helps to control and stabilise the knee during sport, although this has little to do with your lower back pain and more to do with knee function. I will discuss this more in a future post.
We now know how the hamstring muscle moves the body when it contracts, but how does your hamstring move the body when it is stretched? What happens when your hamstrings are tight?
Because the hamstring attaches to the bottom of the pelvis, when the hamstring is stretched, or your hamstring is tight, it will result in your pelvis being rotated backwards which has the knock on affect of flattening the important lumbar curve in your lower back (Read more about the important curves in your spine here). This lumbar curve helps prevent and control lower back pain.
Hamstrings that are on stretch and when they are tight, will negatively affect your lower back and predispose you towards lower back pain, particularly when you are in a sitting posture, for example when you are driving (read my post on driving posture and lower back pain) or during any activity that places your hamstring on stretch (for example during sport like running, kicking etc).
How does one end up with tight hamstrings? Some people are born with them, it’s a genetic predisposition. Other people have tight hamstrings because of an injury to their muscle and the subsequent scarring that results due to the injury in the hamstring muscle. Other people have tight hamstrings as a result of pain in their sciatic nerve (which causes the muscle to go into spasm around the nerve to protect the sciatic nerve from being stretched and further irritated). Tight hamstrings can even be as a result of a mild form of spinae bifidae (a birth defect). However, a lot of people have tight hamstrings because when they use their hamstrings a lot during their daily life (such as in hiking, cycling, exercises in the gym or even lifting at home/work), they fail to adequately stretch them after their activity, slowly causing their hamstrings to tighten. And tight hamstrings, thus predispose you to develop lower back pain.