Lower back conditions

The following glossary provides a brief description of a variety of causes of lower back pain. In reading these descriptions try not to focus on the condition itself, but rather understanding how this may relate to your injury mechanism, symptoms and positive management of your individual case of lower back pain.

Intervertebral Disc Injury: Injury to the intervertebral disc usually occurs with flexion and rotation of the lumbar spine - such as occurs when lifting from a bent and twisted position. This leads to tears in the outer fibres of the disc (annulus), which may or may not lead to bulging or herniation of the intervertebral disc. Intervertebral disc injuries are usually acute, and symptoms include stiffness and generalised deep ache in the lower back, sometimes with aches and pain referring into the buttocks(s) and leg(s). Back pain is usually felt in a band. Symptoms are usually worse with bending and sitting, and may be aggravated by coughing or straining. Pain is usually eased by laying down and is often reduced after a nights rest. Where a disc has herniated or bulged, there may be symptoms of nerve root compression/irritation (see - Nerve Root Compression/Irritation).

When an intervertebral disc bulges/herniates, it can place pressure onto a spinal nerve root where it exits between adjacent vertebrae. This can cause symptoms of nerve root compression and irritation.

Facet Joint Injury: The facet joints in our back are like the other joints in our body -having a joint capsule, cartilage lined surfaces, joint fluid and supporting ligaments. Just like any other joint they can be sprained or strained. Although injury mechanism can vary, facet joints are usually injured with movements involving extension and rotation of the lower back. Symptoms include stiffness and generalised ache in the lower back -usually felt more on one side - sometimes with defined catches or positions of discomfort. There may be aches and pains referred into the buttock(s) and leg(s). Symptoms are usually worse with standing, laying down (especially on your stomach), and negotiating stairs and slopes, as these positions and movements increase pressure through the facet joints. Sitting and rest tend to ease symptoms.

Arthritis: With lots of physical work and ageing the joints and connections in the lumbar spine can display arthritic changes like other joints of the body. Typically, discs lose height as we get older, ligaments thicken and the facet joints become stiffer or arthritic. Thickened bony growths or spurs (osteophytes ) may develop on vertebrae and facet joints as part of this process, leading to further stiffness and/or pain. With significant arthritis there may also be nerve root compression/irritation or stenosis (see - lumbar spinal canal stenosis). Arthritic lower backs are typically very stiff and achy, especially first thing in the morning. They feel better with gentle exercise and movement.

The growth of bony spurs and loss of disc height with arthritis and ageing can contribute to symptoms of nerve root compression and spinal stenosis (narrowing of the spinal canal). Image Credit: Pain Physicians NYC, 2017 (1).

Nerve Root Compression/Irritation: Nerve roots in the lumbar spine can become physically compressed or irritated where they exit the spine in small holes between adjacent vertebrae (openings known as the 'intervertebral foramen'). This usually happens when an intervertebral disc bulges or herniates. It can also happen where a facet joint has significant arthritis or bony growths (see - arthritis). Both these conditions lead to there being less space available for the nerve root in the intervertebral foramen, causing some degree of rubbing or 'squishing' of the nerve. Symptoms are characterised by sharp, shooting pains into a leg felt in localised bands. Abnormal sensory symptoms such as pins and needles or numbness may exist, as well as localised muscle weakness or change reflexes. There may or may not be any lower back pain.

Vertebral End Plate Fracture: An end plate fracture is a unique disc related injury caused by excessive compression of the spine. This may occur with a fall from height to land on feet or tail bone, heavy weight lifting or in an accident. The excessive compression fractures the bone underneath the intervertebral disc, allowing the disc to protrude into the top of the vertebrae. Symptoms are usually worse with impact, weight bearing and coughing/straining. The back is usually very tense and sore.

Spondylolysis (Pars Fracture): Spondylolysis refers to a stress fracture of the vertebral arch (pars interarticularis) in the lumbar spine. This is usually an overuse or repetitive strain type injury that is seen in sports that require repeated extension and rotation of the spine - such as gymnastics, cricket fast bowling, tennis serving or throwing sports. Repetitive extension and rotation eventually leads to small fractures forming in the vertebral arch, with subsequent pain and irritation. Symptoms involve a one sided lower back ache, sometimes extending to the buttocks. This is aggravated by sporting factors, and more noticeable when laying down on your stomach or with prolonged standing.

spondy pic .jpg

A fracture of the vertebral arch (pars interarticularis) can progress to a full fracture where the vertebrae slips forward. Image Credit: American Academy of Orthopaedic Surgeons, 2017 (2)

Spondylolisthesis: This condition occurs when one vertebrae slips forward on another. It occurs when there is pars fractures on both sides of the vertebral arch, and may occur if stress fractures are left untreated. When there is pars fracture on both sides of the vertebral arch, there is a loss of bony connection between adjacent vertebrae, allowing the slippage to occur. This condition can occur in both young athletes and in older individuals due to age related changes. Some people can have a genetic predisposition. Symptoms include localised aches in the lower back (usually felt centrally and down low near the tail bone), sometimes accompanied by sensations of clicking/catching with movement. When there is significant spondylolisthesis, spinal canal narrowing and stenosis results, with subsequent neurological symptoms.

Lumbar Spinal Canal Stenosis: Spinal stenosis refers to a narrowing of the vertebral canal inside the vertebral arch, where the spinal cord and lower spinal nerve roots lie. Stenosis can occur for a number of reasons. In the younger individual, this can be due to a large disc bulge/herniation or due to a significant spondylolisthesis. In older individuals stenosis may occur due to age related changes such as arthritic facet joints or loss of height of the intervertebral discs or thickened spinal ligaments. Symptoms include strong aching pain in the lower back, with pain, heaviness and weakness in the legs. There may be associated pins and needles and numbness in the legs. Symptoms are usually worse with walking and standing, and relieved by rest and bending. When stenosis is severe there may be profound neurological changes warranting immediate medical review.

Lumbar Spine Instability: A condition where one or more segments of the lumbar spine is considered 'unstable' when moving. This may be to a combination of factors, including a loss of passive stability from (e.g. ligament injury or pars fracture) or from a loss of active stability due to poor muscular control of the spine. Where the muscles that help to stabilise and hold together adjacent vertebrae are weakened or not working well, the spine is more likely to buckle, 'twinge', or 'strain' when under load. This leads to symptoms of recurrent injury, feelings of focal tightness and pain. Sometimes sensations of clicking or catching may be experienced.

'Soft tissue Injury' - Muscle and Ligament Injury: Any muscle or ligaments that support or control the spine can be strained or sprained. Muscular strains usually occur when the spine is being loaded, for example when lifting or during sport/exercise. Pain is usually sharp and well localised, reproduced by contraction of the affected muscle. Trigger points (focal areas of tension) in the muscles around the spine (especially the erector spinae, quadratus lumborum and gluteal muscles) can also cause lower back pain, and this may be related to an underlying injury to another spinal structure. Ligament sprains can occur under similar circumstances to muscle strains, or as part of larger injuries such as intervertebral disc injury and fractures of the spine. Where a specific or localised ligament has been injured there is usually focal tenderness and pain when the ligament is stretched in certain directions.

Spinal Fractures: Any vertebrae of the lumbar spine can be fractured where the injury mechanism involves strong enough forces, such as in a car accident, fall or sporting incident. If a persons bone density is poor (such as osteoporosis) a more minor incident could lead to a fracture. Fractures can occur in variety of locations, including the body of the vertebrae, the vertebral arch or the points of bone on the back of the vertebrae (spinous and transverse processes). Fractures are usually intensely painful and there is a clear injury mechanism. Immediate review with scans is needed, often requiring medical review and sometimes surgery to ensure healing. At the time of fracture there is also significant soft tissue damage (related to the forces involved at the time of injury), and there is potential for damage to the spinal cord and nerve structures.

Referred pain from the Hip and Pelvis: In some cases pain in the lower back may be produced by musculoskeletal structures in the hip joint (femero-acetabular joint) or the pelvic joints that connect to the base of the spine (sacroiliac joints). Typically these body areas cause referred pain around the lower most part of the lumbar spine around the tail bone. Symptoms are usually aggravated by factors relating to the movement of loading of the hip and pelvis (such as running, jumping, squatting and stairs), rather than postures and loading of the lower back. Assessment of your hip and pelvis will help to identify if this is causing your lower back pain and if ti requires treatment.  

Unusual/Atypical Causes: As a final note it is important to remember that lower back pain can be related to a variety of non-musculoskeletal (non-mechanical) causes. Of particular note are osteoporosis, malignancy, fibromyalgia, rheumatoid conditions and pain referred from internal organs (such as the kidneys) or internal vascular structures (such as aortic aneurysm). Typically, pain from these conditions does not have a clear mechanical pattern and there is an absence of clear aggravating or relieving factors. Associated factors in an individuals medical history may mean that non-mechanical causes of lower back pain need to be ruled out and reviewed with further medical investigation.


1. Pain Physicians NYC (2017). Lumbar Spinal Stenosis. Retrieved from

2. American Academy of Orthopaedic Surgeons (2017). Spondylolysis and Spondylolisthesis. Retrieved from