How many degrees of fredom are available in the spine?
Describe Fryette's laws of spinal biomechanics?
C-spine: side bend and rot occur to the same side; Lumbar and thoracic in neutral SB and Rot occur to the opposite side; Lumbar and thoracic in flex SB and rot same side; in reality spinal movement is highly variable in the thoracolumbar
Normal ranges for C0-C1
10-15 flex/ext, 8 degrees lateral flexion
Normal ranges: C1-2
10 flex/ext, 45 rot
Normal ranges: C3-7
64 flexion, 24 ext, 40 lateral flexion, 40 rot
Normal ranges: T1-S1
80 flex, 25 ext, 45 rot, 35 lat flexion
Angle of the facets for cerv, thoracic, lumbar:
Cerv: 45; thoracic: 60; lumbar vertical
Loads on the back when seated, standing forward bend, and seated forward bend?
145%, 150%, 180%
What level does the conus medullaris end?
How are facets innervated?
from one segment below and above
What happens during the straight leg raise test?
Neural movement: 0-30degrees slack is taken up, 35-70 the nerve root moves, 70-90 all structures are stretched
How effective are lumbosacral corsets for relief of spinal disk pressure?
Approximately 20-30% reduction in max disk load
What is the problem with supine situps in relation to the back:
high disk pressure therefore should be limited ~210% pressure
Chronic low back pain recruitment of erector spinae vs normal subjects shows what:
earlier and longer recruitment
What effect can a >3cm leg length discrepancy have on the lumbar spine?
Asymmetry in lateral bending during gait leading to accelerated degeneration
What is the role of bed rest in acute back pain
It should be limited, rest from activity but not from function except severe neurlogic involvement
Function of the intervertebral disk:
provides space and position; permits, guides, and restrains motion in all directions
What position facilitates disk nutrition?
sidelying or supine with knees bent
What is the source of diskogenic pain?
Healing response with vascularization and nerve growth causes pain
Describe stiffness in the low back
may occur after an acute injury with lack of movement resulting in collagen cross binging or fibrous adhesions
Describe mechanical block in the low back:
at L4/5 after stooping to pick up an object the joint may become locked in SB'ing; potentially related to a torn or seperated meniscoid or free fragment of articular cartilage
Describe painful capsule entrapment:
This is what is thought to happen in the C-spine after an awkward movement with one sided pain
Difference between protrusion and herniation?
Annular fibers are intact vs being disrupted
How quickly does disk disease resolve:
90-95% resolve in 3-4 months
Is intensive or mild exercise better after disk surgery?
Intensive 4-6 wks post surgery
Manual therapy and disk herniation, is it warranted?
yes, it can help increase movement and get the muscles to relax
What is spinal instability:
Osseoligamentous and neuromuscular components of the spine are unable to hold the spine against aberrant motions and slippage, leading to stress on soft tissues
What is the order of soft tissue disruption with forward flexion injury?
supraspinous lig, interspinous lig, facet capsule, and disk
What is spondylolisthesis?
anterior slippage of one vertebral body on an adj
What is sacral angle?
The angle of displacement of the scarum from the verticle, the scarum becomes more verticle with progressive listhsis