Low Back Pain
With at least 80% of the population suffering from low back pain, it is vital that we take every precaution to offer advice on prevention and ensure that medical treatment is readily available to help with the pain and associated symptoms that can be present with low back pain. There are many injuries and conditions that result in low back pain and in many patients it is left untreated for a significant period of time, which often results in the condition deteriorating.
The following conditions are the most common causes of low back pain and discomfort. If left untreated these conditions may deteriorate and may lead to a more serious condition, discussed later in this chapter.
The prolapsed disc (fig 5) is rare, occurring in approximately 5% of the population, however the disc is also susceptible to other injuries, such as rotational or compressional injuries, which is one of the more common complaints of low back pain. In order to understand disc injuries, it is helpful to understand a little about the anatomy of the disc.
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The lumbar (lower back) region of your spine bears most of the weight of the body and provides the most movement. It is made up of 5 bony vertebrae and each of these are separated by an intervertebral disc (fig 6), which acts as a shock absorber and prevents the vertebrae from rubbing together.
The intervertebral disc is made up of a liquid centre called the nucleus pulposes (fig 7), which is situated in the centre of the disc and is surrounded by the annulus fibrosis (fig 7), which is made up of thin fibrous layers.
Rotational stresses usually affect the annulus fibrosis and can sometimes affect the facet joints, which is the point at which the vertebrae are joined together. The annular fibrosis is most vulnerable to rotational stress when flexion (bending) and rotational (twisting) movements are involved, usually occurring during lifting. Over time, repeated rotational stresses may cause microscopic tears to appear on the annular fibrosis. These repeated rotational stresses can place you at risk to suffering a prolapsed disc.
Compressional stresses can also occur within the disc, which is another cause of low back pain. Compressional stresses are often initiated by a stress fracture to the vertebral end plate and this is often the result of excessive weight bearing. When a stress fracture occurs to the vertebral end plate some of the contents of the intervertebral disc, specifically the nucleus pulposes, can be absorbed into the circulation of the vertebra. This causes an auto immune response to occur within the vertebra, as well as placing an additional strain on the annular fibrosis, often resulting in pain. This injury is often observed in gardeners, those who undertake in heavy lifting and those who land heavy on their feet, such as parachutists and gymnasts etc. Both of these injuries, rotational and compressional, can cause a very deep seated low back pain and may also present with referred pain into the buttock.
Spondylylosis (fig 8) is another spinal condition that can cause low back pain. Spondylylosis is a weakness or stress fracture that occurs to the pars interarticularis (fig 6) and is most commonly seen in adolescent athletes. This condition may also lead from early childhood, where the bone may not have developed properly. Those who suffer from spondylylosis are also at increased risk from developing spondylolisthesis.
The sports that predispose to this injury are those involved in hyperextension of the spine, especially when an element of rotation is involved. Hyperextension of the spine is an excessive movement, backwards, that goes beyond the range of normal movement. The individuals that are predisposed to this injury are those involved in sports, such as gymnastics, bowling in cricket, dancing, wrestling, and high jump etc. Individuals with spondylylosis usually complain of an ache, usually one side, which may or may not include pain in the buttock area and spasm of the hamstrings.
The two other most common conditions that can cause low back pain are sacroiliac joint injuries and muscle strains. The sacroiliac joint is a joint that is situated in between the sacrum and the ilium (fig 9). For many years it was thought that there was not much movement in this joint, but over the years studies have shown that there are significant movement patterns that may cause injury to this joint, with the possibility of causing damage to the surrounding soft tissue.
Injuries to the sacroiliac joint can cause pain in the lower back, buttock, groin and thigh. It can often present with asymmetry of the pelvis, which can lead to secondary damage if left untreated. These include muscle imbalance, biomechanical abnormalities and leg length imbalance.
The back muscles are the main stabilisers of the lower spine. There are many muscles of the spine that control a variety of movements, but the two main muscle groups of the back are extensors and the flexors. The extensor muscles are attached to the back of the spine and they enable us to stand upright and lift objects. The flexor muscles are attached to the front of the spine and enable us to bend forward, lift and they also control the arch of the lower spine. Therefore, if there is poor muscle tone of either or both of these muscle groups, it can place an immense amount of strain on the spine, specifically the lower spine.
Lower spine muscle strains are extremely common and can be caused by a variety of reasons, including:-
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Heavy lifting.
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Contact / heavy impact sports, e.g running.
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Rapid movement, involving twisting.
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Weakness of the spinal muscles.
Many people assume that working through the pain barrier is the best option, but in fact you could be causing yourself even more damage. The best thing to do is to stop at the first signs of pain. There are many different treatments that can be offered and the sooner you undergo treatment, the sooner you will return to fully functional fitness, painfree. It is important at this stage to be assessed and not just to assume that the pain is due to a muscle strain, as there may be damage to other structures, such as discs or joints. You will then be advised of the most appropriate course of action. Once the injury has been successfully treated and the pain has eased, it is advised that you participate in a daily stretching programme, including specific stretches for the lumber spine, strengthening exercises and regular heat treatment to prevent reoccurrence. See muscle strains section for more information.
The following are some of the less common injuries that can cause low back pain. These conditions can cause an extreme amount of pain and discomfort, however they only contribute to approximately 10% of the population who suffer with low back pain.
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Vertebral fractures (fig 10) - often caused by an accident.
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Spinal canal stenosis (fig 11) - a narrowing or constriction of the spinal and nerve-root canal. This is often a result of arthritis, injury, previous surgery or the bodys natural aging process.
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Spondylolisthesis (fig 8) - referring to one or all of the vertebra slipping forward on another. This is due to a weakness or a fracture to the pars interarticularis (fig 6) and is most often caused by spondylylosis.
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Lumbar disc prolapse (fig 5) - referring to the intervertebral disc prolapsing (rupturing) and often compressing on the surrounding neural sensitive structures, caused by a gradual weakening of the disc, from both rotational and compressional forces, over a significant period of time.