Home | Ortho Kinematics University | Glossary of Terms
Glossary of Terms
- Biomarker
- End-range x-rays
- Fluoroscopy
- Hypermobility
- Hypomobility
- Immobility
- Instability
- Intervertebral angle (IVA)
- KineGraph VMA
- KineGraph plot
- Laxity
- Maximum Voluntary Bending Angle (MVBA)
- Motion Normalizer
- Normal
- Normative dataset
- Paradoxical motion
Biomarker
Used as an indicator of biologic state. Typically, a substance that can be objectively measured and evaluated to diagnose normal or abnormal function. Pilot data suggest that by tracking the quality of adjacent level motion over time, the KineGraph VMA could potentially provide a pre-symptomatic mechanical biomarker of adjacent level disease progression.
End-range x-rays
Plain x-ray films taken at the patient’s maximum voluntary trunk bending angle; current standard of care for measuring spine motion clinically.
Fluoroscopy
An imaging technique used to obtain motion images of a patient’s internal structures. Enables the KineGraph VMA to capture the spine in motion, proving a rich set of in vivo biomechanical data.
Hypermobility
Type of instability in which the intervertebral angle (IVA) exceeds the normal range. This excess of motion can occur in a single segment or joint or can refer to the overall quality of a patient’s spine. Hypermobility is known to cause severe low back pain, emerging from the vertebrae sliding so much in different directions, which pulls the soft tissues and the nerves in the area creating pain.
Hypomobility
Stiffness; reduced intervertebral motion, with an intervertebral angle (IVA) below the normal range.
Immobility
A condition where a patient is unable to move the spine normally. Capable of creating pain in the back, neck, and shoulders. Occurs when vertebrae remain immobile throughout the entire trunk bend.
Instability
Refers to the disruption of spinal structure with a loss in the functional integrity of the spine. It can result from injury or degeneration of discs or vertebrae, or it can be a congenital condition. Instability suggests that the movement of both the vertebrae and the discs has become abnormal in a structurally compromising way. Possible effects of instability include nerve compression and even visual deformity.
Intervertebral angle (IVA)
The relative change in angle between two vertebrae during spine bending; a measurement used to evaluate spine function.
KineGraph VMA
Vertebral motion analyzer; a new functional diagnostic test for the spine that uses fluoroscopy to capture the spine in motion. The output is the KineGraph plot.
KineGraph plot
The quantitative output of the KineGraph VMA; a plot of the intervertebral motion as a function of degree of trunk bending; a unique kinematic autograph of a patient’s intervertebral motion.
Laxity
A type of instability where the disc’s elastic function is compromised. to the extent that the joint becomes “loose”. With laxity, there is an abnormally high amount of “slack” in the way the vertebrae move.
Maximum Voluntary Bending Angle (MVBA)
To take end-range x-rays, patients are asked to move to bend their spine own personal maximum bending angle. Differences in compliance and pain threshold among patients contribute to variability among patients.
Motion Normalizer
A key, proprietary innovation of the KineGraph VMA™; device which provides powered, passive trunk bending in either a standing or lying down configuration.
Normal
Subjects in the normative dataset who fall under the bell curve at plus or minus two standard deviations from the mean; approximately 95.5% of the population.
Normative dataset
Population of asymptomatic subjects used to define the range of normal.
Paradoxical motion
Condition where the vertebral space opens the in the direction opposite of trunk bending; results in an intervertebral angle (IVA) of less than zero. May create abnormal curvatures in the spine which may worsen over time and eventually morph into a condition such as kyphosis, meaning a forward curvature of the upper spine.
