Lumbar 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.
Lumbar hyperlordosis Lumbar hyperlordosis is a condition that occurs when the
lumbar region (lower back) experiences stress or extra weight and becomes arched more than normal, sometimes leading to muscle pain or spasms. It is a common postural position in which the natural curve of the lumbar region of the back is slightly or dramatically accentuated. Commonly known as swayback, it is common in dancers. Imbalances in muscle strength and length are one cause of this excessive stress to the lower back, such as weak
hamstrings and tight
hip flexors (psoai). 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),
discitis (inflammation of the intervertebral disc space caused by infection), and benign juvenile lordosis. Other factors may also include rare diseases, including
Ehlers–Danlos syndrome (EDS), where some joints throughout the body are so hyper-extensible that they can become unstable (i.e. problematically much more flexible than normal, frequently to the point of partial or full dislocation). With such hyper-extensibility, it is also quite common (if not the norm) for some of the muscles surrounding an unstable joint to compensate for that instability by contracting. 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. 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.
Lumbar hypolordosis 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. ==Signs and symptoms==