Lordosis

Normal lordotic curvatures, also known as secondary curvatures, result in a difference in the thickness between the front and back parts of the intervertebral disc. Lordosis may also increase at puberty, sometimes not becoming evident until the early or mid-20s.

In radiology, a lordotic view is an X-ray taken of a patient leaning backward.[7]

Lumbar hyperlordosis

Lumbar hyperlordosis is a condition that occurs when the lumbar region (lower back) experiences stress or extra weight and is arched to point of muscle pain or spasms. Lumbar hyperlordosis is a common postural position where the natural curve of the lumbar region of the back is slightly or dramatically accentuated. Commonly known as swayback, it is common in dancers.[8] Imbalances in muscle strength and length are also a cause, such as weak hamstrings, or tight hip flexors (psoas). A major feature of lumbar hyperlordosis is a forward pelvic tilt, resulting in the pelvis resting on top of the thighs.

Other health conditions and disorders can cause hyperlordosis. Achondroplasia (a disorder where bones grow abnormally which can result in short stature as in dwarfism), Spondylolisthesis (a condition in which vertebrae slip forward) and osteoporosis (the most common bone disease in which bone density is lost resulting in bone weakness and increased likelihood of fracture) are some of the most common causes of hyperlordosis. Other causes include obesity, hyperkyphosis (spine curvature disorder in which the thoracic curvature is abnormally rounded), discitits (an inflammation of the intervertebral disc space caused by infection) and benign juvenile lordosis.[9] Other factors may also include those with rare diseases, as is the case with Ehlers Danlos Syndrome (EDS), where hyper-extensive and usually unstable joints (e.g. joints that are problematically much more flexible, frequently to the point of partial or full dislocation) are quite common throughout the body. With such hyper-extensibility, it is also quite common (if not the norm) to find the muscles surrounding the joints to be a major source of compensation when such instability exists.

Excessive lordotic curvature – lumbar hyperlordosis, is also called "hollow back", and "saddle back" (after a similar condition that affects some horses); swayback usually refers to a nearly opposite postural misalignment that can initially look quite similar.[10][11] Common causes of lumbar hyperlordosis include tight low back muscles, excessive visceral fat, and pregnancy. Rickets, a vitamin D deficiency in children, can cause lumbar hyperlordosis.

Being less common than lumbar hyperlordosis, hypolordosis (also known as flatback) occurs when there's less of a curve in the lower back or a flattening of the lower back. This occurs because the vertebrae are oriented toward the back of the spine, stretching the disc towards the back and compressing it in the front. This can cause a narrowing of the opening for the nerves, potentially pinching them.

Precise diagnosis is done by looking at a complete medical history, physical examination and other tests of the patient. X-rays are used to measure the lumbar curvature. On a lateral X-ray, a normal range of the lordotic curvature of between 20° and 60° has been proposed by Stagnara et al., as measured from the inferior endplate of T12 to the inferior endplate of L5.[17] The Scoliosis Research Society has proposed a range of 40° and 60° as measured between the upper endplate of Th12 and the upper endplate of S1.[17] Individual studies, although using other reference points, have found normal ranges up to approximately 85°.[17] It is generally more pronounced in females.[17] It is relatively constant through adolescence and young adulthood, but decreases in the elderly.[17]

Bone scans are conducted in order to rule out possible fractures and infections, magnetic resonance imaging (MRI) is used to eliminate the possibility of spinal cord or nerve abnormalities, and computed tomography scans (CT scans) are used to get a more detailed image of the bones, muscles and organs of the lumbar region.[18]

Some corrective exercises can be done to alleviate this issue, it may take several months to fix (provided that the person sits less, stands with a neutral pelvis and sleeps on their back).

Since lumbar hyperlordosis is usually caused by habitual poor posture, rather than by an inherent physical defect like scoliosis or hyperkyphosis, it can be reversed.[19] This can be accomplished by stretching the lower back, hip-flexors, quads and strengthening the abdominal muscles, hamstrings and glutes. Strengthening the gluteal complex is a commonly accepted practice to reverse excessive lumbar lordosis, as an increase in gluteals muscle tone assist in the reduction excessive anterior pelvic tilt and lumbar hyperlordosis.[20] Local intra-articular hip pain has been shown to inhibit gluteal contraction potential,[21] meaning that hip pain could be a main contributing factor to gluteal inhibition. Dancers should ensure that they don't strain themselves during dance rehearsals and performances. To help with lifts, the concept of isometric contraction, during which the length of muscle remains the same during contraction, is important for stability and posture.[22]

Lumbar hyperlordosis may be treated by strengthening the hip extensors on the back of the thighs, and by stretching the hip flexors on the front of the thighs.

Only the muscles on the front and on the back of the thighs can rotate the pelvis forward or backward while in a standing position because they can discharge the force on the ground through the legs and feet. Abdominal muscles and erector spinae can't discharge force on an anchor point while standing, unless one is holding his hands somewhere, hence their function will be to flex or extend the torso, not the hip. Back hyper-extensions on a Roman chair or inflatable ball will strengthen all the posterior chain and will treat hyperlordosis. So too will stiff legged deadlifts and supine hip lifts and any other similar movement strengthening the posterior chain without involving the hip flexors in the front of the thighs. Abdominal exercises could be avoided altogether if they stimulate too much the psoas and the other hip flexors.

Controversy regarding the degree to which manipulative therapy can help a patient still exists. If therapeutic measures reduce symptoms, but not the measurable degree of lordotic curvature, this could be viewed as a successful outcome of treatment, though based solely on subjective data. The presence of measurable abnormality does not automatically equate with a level of reported symptoms.[23]

The Boston brace is a plastic exterior that can be made with a small amount of lordosis to minimize stresses on discs that have experienced herniated discs. In the case where Ehlers Danlos syndrome (EDS) is responsible, being properly fitted with a customized brace may be a solution to avoid strain and limit the frequency of instability.

While not really a 'treatment', the art of tai chi chuan calls for adjusting the lower back curvature (as well as the rest of the spinal curvatures) through specific re-alignments of the pelvis to the thighs, it's referred to in shorthand as 'dropping the tailbone'. The specifics of the structural change are school specific, and are part of the jibengong (essential technique) of these schools. The adjustment is referred to in tai chi chuan literature as 'when the lowest vertebrae are plumb erect...'[24]