The sacrum, in human anatomy, is a large, triangular bone at the base of the spine that forms by the fusing of the sacral vertebrae (S1–S5) between ages 18 and 30.
The lumbar vertebrae are located between the thoracic vertebrae and pelvis. They form the lower part of the human back in humans, and the tail end of the back in quadrupeds. In humans, there are five lumbar vertebrae. The term is used to describe the anatomy of humans and quadrupeds, such as horses, pigs, or cattle. These bones are found in particular cuts of meat, including tenderloin or sirloin steak.
Kyphosis is an abnormally excessive convex curvature of the spine as it occurs in the thoracic and sacral regions. Abnormal inward concave lordotic curving of the cervical and lumbar regions of the spine is called lordosis.
A laminectomy is a surgical procedure that removes a portion of a vertebra called the lamina, which is the roof of the spinal canal. It is a major spine operation with residual scar tissue and may result in postlaminectomy syndrome. Depending on the problem, more conservative treatments may be viable.
Spondylosis is the degeneration of the vertebral column from any cause. In the more narrow sense it refers to spinal osteoarthritis, the age-related degeneration of the spinal column, which is the most common cause of spondylosis. The degenerative process in osteoarthritis chiefly affects the vertebral bodies, the neural foramina and the facet joints. If severe, it may cause pressure on the spinal cord or nerve roots with subsequent sensory or motor disturbances, such as pain, paresthesia, imbalance, and muscle weakness in the limbs.
In tetrapods, cervical vertebrae are the vertebrae of the neck, immediately below the skull. Truncal vertebrae lie caudal of cervical vertebrae. In sauropsid species, the cervical vertebrae bear cervical ribs. In lizards and saurischian dinosaurs, the cervical ribs are large; in birds, they are small and completely fused to the vertebrae. The vertebral transverse processes of mammals are homologous to the cervical ribs of other amniotes. Most mammals have seven cervical vertebrae, with the only three known exceptions being the manatee with six, the two-toed sloth with five or six, and the three-toed sloth with nine.
In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebrae of intermediate size between the cervical and lumbar vertebrae; they increase in size going towards the lumbar vertebrae. They are distinguished by the presence of facets on the sides of the bodies for articulation with the heads of the ribs, as well as facets on the transverse processes of all, except the eleventh and twelfth, for articulation with the tubercles of the ribs. By convention, the human thoracic vertebrae are numbered T1–T12, with the first one (T1) located closest to the skull and the others going down the spine toward the lumbar region.
A cervical fracture, commonly called a broken neck, is a fracture of any of the seven cervical vertebrae in the neck. Examples of common causes in humans are traffic collisions and diving into shallow water. Abnormal movement of neck bones or pieces of bone can cause a spinal cord injury, resulting in loss of sensation, paralysis, or usually death soon thereafter, primarily via compromising neurological supply to the respiratory muscles and innervation to the heart.
Degenerative disc disease (DDD) is a medical condition typically brought on by the aging process in which there are anatomic changes and possibly a loss of function of one or more intervertebral discs of the spine. DDD can take place with or without symptoms, but is typically identified once symptoms arise. The root cause is thought to be loss of soluble proteins within the fluid contained in the disc with resultant reduction of the oncotic pressure, which in turn causes loss of fluid volume. Normal downward forces cause the affected disc to lose height, and the distance between vertebrae is reduced. The anulus fibrosus, the tough outer layers of a disc, also weakens. This loss of height causes laxity of the longitudinal ligaments, which may allow anterior, posterior, or lateral shifting of the vertebral bodies, causing facet joint malalignment and arthritis; scoliosis; cervical hyperlordosis; thoracic hyperkyphosis; lumbar hyperlordosis; narrowing of the space available for the spinal tract within the vertebra ; or narrowing of the space through which a spinal nerve exits with resultant inflammation and impingement of a spinal nerve, causing a radiculopathy.
Spinal fusion, also called spondylodesis or spondylosyndesis, is a surgery performed by orthopaedic surgeons or neurosurgeons that joins two or more vertebrae. This procedure can be performed at any level in the spine and prevents any movement between the fused vertebrae. There are many types of spinal fusion and each technique involves using bone grafting—either from the patient (autograft), donor (allograft), or artificial bone substitutes—to help the bones heal together. Additional hardware is often used to hold the bones in place while the graft fuses the two vertebrae together. The placement of hardware can be guided by fluoroscopy, navigation systems, or robotics.
The anterior longitudinal ligament is a ligament that extends across the anterior/ventral aspect of the vertebral bodies and intervertebral discs the spine.
A polyaxial screw is used for connecting vertebrae to rods in spinal surgery, particularly spinal fusion procedures. It is a type of screw whose spherical head is enclosed in a housing, which allows the screw a range of motion along several different axes relative to the housing. The ball joint allows the surgeon some flexibility in placing the screws. The screws are typically placed into the pedicle of the vertebra.
Spondylolysis is a defect or stress fracture in the pars interarticularis of the vertebral arch. The vast majority of cases occur in the lower lumbar vertebrae (L5), but spondylolysis may also occur in the cervical vertebrae.
A laminotomy is an orthopaedic neurosurgical procedure that removes part of the lamina of a vertebral arch in order to relieve pressure in the vertebral canal. A laminotomy is less invasive than conventional vertebral column surgery techniques, such as laminectomy because it leaves more ligaments and muscles attached to the spinous process intact and it requires removing less bone from the vertebra. As a result, laminotomies typically have a faster recovery time and result in fewer postoperative complications. Nevertheless, possible risks can occur during or after the procedure like infection, hematomas, and dural tears. Laminotomies are commonly performed as treatment for lumbar spinal stenosis and herniated disks. MRI and CT scans are often used pre- and post surgery to determine if the procedure was successful.
Laminoplasty is an orthopaedic/neurosurgical surgical procedure for treating spinal stenosis by relieving pressure on the spinal cord. The main purpose of this procedure is to provide relief to patients who may have symptoms of numbness, pain, or weakness in arm movement. The procedure involves cutting the lamina on both sides of the affected vertebrae and then "swinging" the freed flap of bone open thus relieving the pressure on the spinal cord. The spinous process may be removed to allow the lamina bone flap to be swung open. The bone flap is then propped open using small wedges or pieces of bone such that the enlarged spinal canal will remain in place.
An interbody fusion cage is a prosthesis used in spinal fusion procedures to maintain foraminal height and decompression. They are cylindrical or square-shaped devices, and usually threaded. There are several varieties: the Harms cage, Ray cage, Pyramesh cage, InterFix cage, and lordotic LT cage, all of which are made from titanium; the Brantigan cage, made from carbon fibre; and the Cortical Bone Dowel, which is cut from allograft femur. The cages can be packed with autologous bone material in order to promote arthrodesis. Such implants are inserted when the space between the spinal discs is distracted, such that the implant, when threaded, is compressed like a screw. Unthreaded implants, such as the Harms and Pyramesh cages have teeth along both surfaces that bite into the end plates.
The vertebral column, also known as the spinal column, spine or backbone, is the core part of the axial skeleton in vertebrate animals. The vertebral column is the defining and eponymous characteristic of the vertebrate endoskeleton, where the notochord found in all chordates has been replaced by a segmented series of mineralized irregular bones called vertebrae, separated by fibrocartilaginous intervertebral discs. The dorsal portion of the vertebral column houses the spinal canal, an elongated cavity formed by alignment of the vertebral neural arches that encloses and protects the spinal cord, with spinal nerves exiting via the intervertebral foramina to innervate each body segments.
Each vertebra is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spinal segment and the particular species.
SpineGuard, S.A. is a French company that develops and markets probes for the enhancement of spine surgery. The probes, termed PediGuard devices, assist spine surgeons in more accurately drilling a pilot hole in preparation for pedicle screw insertion.
The management of scoliosis is complex and is determined primarily by the type of scoliosis encountered: syndromic, congenital, neuromuscular, or idiopathic. Treatment options for idiopathic scoliosis are determined in part by the severity of the curvature and skeletal maturity, which together help predict the likelihood of progression. Non-surgical treatment should be pro-active with intervention performed early as "Best results were obtained in 10-25 degrees scoliosis which is a good indication to start therapy before more structural changes within the spine establish." Treatment options have historically been categorized under the following types:
- Observation
- Bracing
- Specialized physical therapy
- Surgery
