Final Flashcards
What is a plane?
• A flat surface determined by the position of three points in space: sagittal; frontal (coronal); transverse (axial)
What is plane motion?
• Motion in which all points of a rigid body move parallel to a fixed plane (2-D)
What motion occurs in the sagittal, frontal, and transverse planes?
- Sagittal: flexion, extensions
- Frontal: right lateral flexion, left lateral flexion
- Transverse: rotation
What is out of plane motion?
• All points of a rigid body do not move in a single plane (3-D)
What is an axis?
• A line; rotation or translation occur around /along it
What is the x-axis?
• Line passes horizontally from side to side; frontal or coronal axis; mov’t around it is in sagittal plane
What is the y-axis?
• Longitudinal or vertical axis; perpendicular to ground; axis of the transverse plane
What is the z-axis?
• Sagittal axis; lie from back to front; axis of the frontal plane
What are degrees of freedom?
• Number of ways a body can move; one degree is translation or rotation about one axis; spinal segments have 6 degrees (3 translations and 3 rotations)
What is the instantaneous axis of rotation (IAR)?
• An axis perpendicular to the plane of motion that passes through a point that is instantaneously not moving; used to describe any vertebral motion in a 2-D plane; can shift with different force vectors applied to a vertebra; differs under changing loads, and is different for cervical, thoracic, and lumbar spinal segments
What is a motion segment?
• The functional unit of the spine; smallest spinal segment with biomechanical characteristics similar to those of entire spine; 2 adjacent vertebrae and their interconnecting disc, joints, capsule, and ligaments; 6 degrees of freedom
What is coupled motion?
• Consistent association of one motion (translation or rotation) about one axis with another motion about a second axis; one motion cannot be produced without the other; two motions occurring at the same time along two different axes
What is an example of coupled motion?
• Bending neck to left or right, to the left involves right coupled axial rotation of the upper cervical spine, and left coupled AR of the subaxial cervical spine; and vice versa
What is loose-packed joint position?
• Joint capsule and ligaments are most relaxed; maximum joint play is possible; articulating surfaces are maximally separated; position used for traction or joint mobilization; Ex: when facet joints are half-way between flexion and extension
What is closed-packed joint position?
Capsule and ligaments are maximally tightened; there is no joint play; there is maximal contact b/w the articular surfaces; Ex: when facet joints are in full flexion or extension
• What is the breakdown of the vertebrae, including numbers in regions and curvature?
o 33 vertebrae- 7 cervical, 12 thoracic, 5 lumbar, sacrum (5 fused), coccyx (4 fused)
o Kyphosis in thoracic and sacral; lordosis in cervical and lumbar
• What are the regional spinal coupling patterns seen in left lateral flexion?
LLF outweighs RLF, which is seen to some degree in C2-T1(slight) and T1-L1 (moderate)
• What is the flexion-extension regional range of motion of vertebrae?
o Cervical: great, peaks at C4
o Thoracic: low
o Lumbar: greater, peaking at S1
• What is the lateral bending regional range of motion of vertebrae?
o Cervical: high, peaks at C3-C4
o Thoracic: lower/moderate, no peaks
o Lumbar: moderate, peaks at T12, L4
• What is the axial rotation regional range of motion of vertebrae?
o Cervical: great peak at C1
o Thoracic: higher than most C, and L, peak at T1
o Lumbar: very little
• What is the breakdown of flexion and extension regional range of motion of vertebrae?
o Flexion: lumbar most, then cervical, then thoracic (all roughly similar)
o Extension: cervical most, then lumbar, then thoracic (T and L ~same)
-~ 135d total both flex and ext
• What is the breakdown of lateral flexion regional range of motion of vertebrae?
o Equal to right and left; cervical -> lumbar -> thoracic (roughly equal); <90d total to one side
• What is the breakdown of regional axial rotation range of motion of vertebrae?
o Equal to right and left; cervical -> thoracic -> lumbar; ~170 total to one side
• What is the articular anatomy of the occiput (CO)?
o Has 2 condyles, face laterally and inferiorly, form convex rockers, sit in concave surface of superior articular facet of C1