Fryettes Flashcards
Simple physiologic motion of the spine is comprised of three cardinal motions:
I.Rotation
II.Side-bending
III.Flexion/Extension/Neutral
Rotation:
Transverse (Horizontal) Plane; Vertical Axis
Side-bending:
Coronal (Frontal) Plane; Anterior-Posterior Axis
Flexion/Extension:
Sagittal Plane; Transverse Axis
Neutral
- Neutral:The point of balance of an articular surface from which all the motions physiologic to that articulation may take place2.
- NOTE:Neutral is not a single point, but rather a RANGE in which the weight of the trunk is borne on the vertebral bodies and discs3.
Non-Neutral
Flexion(Forward Bending) or Extension(Backward Bending) beyond the neutral range, engaging the facet (zygapophysial) joints.
Motion of What Exactly?
General spinal motion occurs at the level of the vertebral unit.
•Vertebral Unit: Two adjacent vertebrae (vertebral segments) and their associated arthrodial, ligamentous, muscular, vascular, neural and lymphatic elements2.
Anterior Segment
Structure:
•Vertebral Bodies
•Vertebral Discs
•Longitudinal Ligaments*
Function:
•Load Bearing
Posterior Segment
Structure: •Vertebral Arches •Facet (Zygapophysial) Joints •Transverse Processes •Spinous Processes •Ligaments*
Function:
•Guide and Limit Motion
Conventions
- Vertebral Units are named for the superior member (vertebrae) of the unit.
- All spinal and vertebral movements are described in relation to the motions of their anterior and superior surfaces.
Fryette’s Principles:Complex Physiologic Motion
I.
In the NEUTRALrange, side-bending and rotation are coupled in OPPOSITEdirections = Type I Mechanics
Fryette’s Principles:Complex Physiologic Motion
II.
In sufficient flexion or extension (NON-NEUTRAL), side-bending and rotation are coupled in the SAMEdirection = Type II Mechanics
Fryette’s Principles:Complex Physiologic Motion
III.
Initiating movement of a vertebral segment in any plane of motion will modify the movement of that segment in other planes of motion.
Fryette’s Principles (I and II) apply only to
thoracic and lumbar vertebrae.
Fryette’s 1stPrinciple
Principal I
In neutral position:
Side-bending and rotation occur in opposite directions.
Neutral(Type I) Mechanics
When the spine is in a neutral position and side-bending is introduced, the bodies of the vertebrae will rotate toward the convexity2.
Fryette’s 2ndPrinciple
Principle II
In Non-Neutral Position (flexed or extended):
Rotation and side-bending are to the same side.
Non-Neutral (Type II) Mechanics
When the spine is either forward or backward bent and side-bending is introduced, the vertebrae will rotate toward the concavity2.
Flexion
Forward or anterior bending in the sagittal plane around a transverse axis (past the neutral range).
Extension
Backward or posterior bending in the sagittal plane around a transverse axis (past the neutral range).
Fryette’s 3rdPrinciple
Principle III
When motion occurs in any one plane within a joint, the motion in all other planes of that joint will be influenced.
Note: Fryette’s third principle applies to cervical, thoracic and lumbar vertebrae.
From Physiologic Motion to Somatic Dysfunction
•When complex physiologic Type I or Type II mechanics of a vertebral unit are restricted in any plane of motion, we have somatic dysfunction. (Remember Principle III?)
–A dysfunction exists when the spine is placed in a neutral position and a spinal segment or group is not in neutral (i.e. its motionor landmarksare asymmetric).
Arthrodial (Joint) Restriction
–Thin Layer Adherence at Facet Joints
•Maintained by muscle hypertonicity
Muscular Restriction
–Longer paraspinal musclesmaintain Type I dysfunctions
•Often postural compensation/chronic process
–Short paraspinal musclesmaintain Type II dysfunctions
•Often acute process
Fascial and Ligamentous Restriction
–Fibrosis/scarring/inflammation can shorten fascia and ligaments associated with paraspinal muscles
Edema
–Interstitial fluid distends, stretches, and restricts tissues, causing motion restriction
A GROUP of vertebrae stuck in
Type I Mechanics.
–Example: L1-4 sidebent right and rotated left and not improving with flexion or extension.
–Often a postural compensation/chronic process maintained by long paraspinal muscles
Long Paraspinals:Type I Dysfunctions
Intermediate:
Serratus posterior superior & inferior
Deep:
Splenius
Erector Spinae:
Spinalis
Longissimus
Iliocostalis
A SINGLE vertebrae stuck in
Type II Mechanics
–Example T7 is flexed and sidebent and rotated to the left
–Often an acute process maintained by short paraspinal muscles
Short Paraspinals:Type II dysfunctions
Deep Muscles of the Back:
Transversospinal group
Semispinalis
Multifidus
Rotatores
Intersegmental Muscles
Interspinalis
Intertransversarii
LevatorcostarumThe rule of threes
Distance Spinous process is below transverse processes
1-3 are the same level 4-6 are 1/2" inferior 7-9 are 1" inferior 10 is 1" inferior 11 is 1/2" inferior 12 is the same level
Superior Scapular Border =
T2 SP
Scapular spine =
T3 SP
Scapular Angle =
T7 SP
Iliac Crests
L4 SP
Somatic dysfunctions are named for the direction of
ease (freer motion), NOT for the direction of restriction
Whichever direction motion is restricted, the somatic dysfunction is in the
opposite direction.
–Example: If a vertebra is “restricted in right rotation,” we know that it is rotated left.
–This will hold true for any direction tacked on to the end of this phrase.
