Lumbar Spine instability Flashcards
what causes excessive motion of a segment or segments
- lacks normal restrain from
- facets and capsules
- ligaments
- disc
- muscles
What are the segmental Zones
- Neutral zone
- Elastic zone
= the total ROM at a segment
Neutral zone
- segment postition or movement in the normal laxity zone
*minimal loading of *
- passive structures
- IV disc
- facet joint capsules
- ligaments
- Active structures: musucles and tendons
The elastic zone
position and movement of a segment where:
- there is a substantial loading of passive structures
- found at end ranges
- creep: ligaments some resistance, repetitive loading or sustain posures can change the viscoelastic nature of the tissues
- Inert tissues; capusle ligaments
Segmental Control: 3 system
- Passive control
- Active Control system
- neural control system
Passive control
What are they and what occurs when there is damage?
- inert tissue resistance during static and dynmaic activities
- IV disc
- facet joint capsules
- ligaments
Damage to these structures result in:
- decreased proprioceptive feedback
- increase size of the neutral zone
Active control system
- muscles and their tendons
- dynamic function maintains spine stabilty
- when passive control structures are inadequate
- two components: local and global muscular system
Neural control system
- maintenance of segmental stability
Via input from
- passive control system: capsule and ligaments –joint/mechanoreceptors
- active control systems: muscles –spindles
- neural control system dysfunction - spine strutcture at risk
Look at segmental control summary slide
look
Active system control
types
- local system
- global system
Active system control
local system
- role is segmental stabilization
- key stabilizers in the spine are multifidi (TP-SP runs 2-4 segments)
- transverse abdominus, internal oblqiues corset/cylinders increase intra-abdominal pressure
- attachments into thoraco-lumbar fasccia
Active muscular control
Global system
- general trunk/spine stabilization
- larger torque producing muscles
- linking pelvis, spine and extremities
Include:
- rectus abdominus
- external obliques
- erector spinae
- latissimus dorsi
- gluteus maximus
*strengthen locally first then globably
LS stability: local system muscular role
What are they and when are they active
- multifidus, TrA, IO are tonically active in upright postures and motions of the trunk
- TrA recruited prior to movement
- TrA, IO make rigid corset
- local muscle system for segmental stability
- multifidus, TrA, IO - are most important muscules
LS stability: local system malfunction
- in presence of L/S injury and LBP
- inhibition of TrA, multifidus
- result = poor stabilization by this local system
What is spondylolysis
- breakdown of vertebrae without vertebral slippage
- fx of pars interarticularis (lamina)