Ryan Tauzell, MA, PT, Cert. MDT
Disclosures
 None
History
Knuttson: Method of diagnosing segmental
instability by measuring sagittal plane translation
and rotation with lateral flexion/extension
radiographs, then compared to normal ranges
History
Knuttson: Method of diagnosing segmental
instability by measuring sagittal plane translation
and rotation with lateral flexion/extension
radiographs, then compared to normal ranges
History
White and Panjabi: Defined criteria for diagnosing instability
-Sagittal translation > 4.5mm, or > 15% vertebral body width
-Sagittal rotation > 15o at L1-2, L2-3, or L3-4,
> 20o at L4-5 or 25o at L5-S1
History
White and Panjabi: Defined criteria for diagnosing instability
-Sagittal translation > 4.5mm, or > 15% vertebral body width
-Sagittal rotation > 15o at L1-2, L2-3, or L3-4,
> 20o at L4-5 or 25o at L5-S1
History
Panjabi: presents a conceptual model of the spinal
stabilization system, the neutral zone and clinical instability
History
Panjabi: presents a conceptual model of the spinal
stabilization system, the neutral zone and clinical instability
History
Multiple studies on lumbar clinical instability and its role in LBP
How far have we come in nearly 70 years?
Definitions
 Clinical Instability (Panjabi, 1992)
“A significant decrease in the capacity of the stabilizing
system of the spine to maintain the intervertebral neutral
zones within the physiological limits so that there is no
neurological dysfunction, no major deformity, and no
incapacitating pain”
Stabilization System
(3 Subsystems)
Vertebrae
Facets
Discs
Ligaments
Muscles
Tendons
Passive
Active
Neural
Control
CNS
Nerves
Feedback System
Subsystem Dysfunction?
Passive
Active
Compensatory
response from
other
subsystems
Passive
Active
Response to Subsystem Dysfunction
Conceptual Response
1. Immediate successful
compensation from
other subsystems
Conceptual Outcome
2. Long-term
compensation from
one or more
subsystems
Normal function with
altered stabilization
system
3. Injury to one or more
subsystems
Normal Function
Overall system dysfunction,
LBP
Definitions
 Clinical Instability (Panjabi, 1992)
“A significant decrease in the capacity of the stabilizing
system of the spine to maintain the intervertebral neutral
zones within the physiological limits so that there is no
neurological dysfunction, no major deformity, and no
incapacitating pain”
Neutral Zone
 “That part of the range of the intervertebral motion,
measured from the neutral position, within which the
spinal motion is produced with a minimal internal
resistance.” (Panjabi)
 Zone of high flexibility or laxity
Elastic Zone
 “That part of the physiological intervertebral motion,
measured from the end of the neutral zone up to the
physiological limit.”
 Zone of high stiffness/resistance
Diagram of IV movement(Biely et al.)
High Laxity
Zone ROM
Weakness or
Injury
Zone ROM
Strengthening,
Osteophytes, Fusion
High Resistance
Neutral Zone + Elastic Zone = Physiological ROM
Theoretical Construct
Definitions
 Radiographic Instability: No standardized definition
Radiographic
Limitations
 Lateral Flexion/Extension:
 No standardized procedure
 False positives
 Variation in asymptomatic subjects
 Variable limits for cutoff values to diagnose instability
 Slight variation in patient position of direction of beam can produce 10%15% variation in displacement measure
 Provides no information about the active and neural components
 Provides no information on what is occurring within range
 Can not reliably correlate abnormal image to pain/disability
 Clinical instability can exist without radiographic evidence of instability
Validity of Clinical Instability
A
D
T
O
Are assessment protocols/tools available
to accurately/reliably diagnose clinical
instability?
Once clinical instability is diagnosed, is
there agreement on an established
treatment?
What is the best treatment for lumbar
instability?
Spratt KF, Weinstein JN. Chapter 25: Measuring clinical outcomes. In: Weisel S, ed. The Lumbar Spine.
2nd ed. v. 2. Philadelphia: W.B. Saunders Co., 1996:1313-1338
Prevalence
 Depending on the cutoff limits and the study
 12% of patients manually assessed for lumbar
segmental instability (Abbott JH, McCane B, Herbison P, Moginie G, Chapple C and Hogarty
T. Lumbar segmental instability: a criterion-related validity study of manual therapy assessment. BMC Musculoskeletal
Disorders. 2005;6:56. http://dx.doi.org/ doi:10.1186/1471-2474-6-56)
 57% patients referred for flex/ext radiographs
based on suspicion of instability (Fritz JM, Piva SR, Childs JD. Accuracy of the
clinical examination to predict radiographic instability of the lumbar spine. Eur Spine J. 2005;14:743-750.
http://dx.doi.org/10.1007/s00586-004-0803-4)
Is Lumbar Instability a Valid Subgroup?
 Abbott et al. (2006) concluded lumbar segmental mobility disorders are a






valid means of defining sub-groups within NSLBP in a conservative care
population of patients with recurrent CLBP
Prospective cohort of 138 consecutive patients with RCLBP, Roland Morris
and VAS scores obtained
Sagittal angular rotation and translation of each lumbar segment was
measured on radiograph then compared to reference range derived from a
study of 30 asymptomatic volunteers
Lumbar Segmental Mobility Disorder (LSMD) defined as 2sd from reference
mean
Normal reference intervals developed using 2 models (Gaussian, novel
normalized within-subjects)
Rotational Instability: 23%
Translational Instability: 32%
Is Lumbar Instability Associated with pain/disability?
 LSMDs are a valid means of defining sub-groups within NSLBP
 Abbott et al.(2006): Among patients with RCLBP, presence of
any LSMD, regardless of how defined, does not appear to be
strongly associated with greater levels of pain or disability
compared to patients with other forms of NSLBP without
LSMDs
Assessment to Diagnosis
 Abdullah et al. Clinical Test to Diagnose Lumbar Segmental Instability: A Systematic








Review
Hicks et al. Interrater Reliability of Clinical Examination Measures for Identification
of Lumbar Segmental Instability
Hicks et al. Preliminary Development of a Clinical Prediction Rule for Determining
Which Patients With LBP Will Repsond to a Stabilization Exercise Program
Abbott et al. Lumbar Segemental Mobility Disorders: Comparison of Two Methods
of Defining Abnormal Displacement Kinematics in a Cohort of Patients with NSLBP
Demoulin et al. Lumbar Functional Instability: A Critical Appraisal of the Literature
Fritz et al. Accuracy of the Clinical Examination to Predict Radiographic Instability of
the Lumbar Spine
Abbott et al. Lumbar Segmental Instability: A Criterion-Related Validity Study of
Manual Therapy Assessment
Cook et al. Subjective and Objective Descriptors of Clinical Lumbar Spine Instability:
A Delphi Study
Kasai et al. A New Evaluation Method for Lumbar Spinal Instability: Passive Lumbar
Extension Test
Study Mix
 Prospective Cohorts: 5
 Single group repeated measure interrater reliability study: 1
 Critical Appraisal of Literature: 1
 Delphi Study: 1
 Systematic Review: 1
Assessment to Diagnosis
Tests/Criteria Available
History
Passive
Active
Age less than 40
Beighton Ligamentous Laxity Scale
Prone Instability Test
“Giving way” “Giving out” “Catching”
“Locking”
Avg SLR > 91o
Aberrant Motions
Temp. Relief with bracing
Passive Lumber Extension Test
Total Flexion > 53o
Self manipulator
Posterior Shear Test
Total Extension > 26o
Pain with transitions
PAIVM
Sit to stand test
Pain with sudden movement
PPIVM (flexion)
Instability Catch Sign
Difficulty sitting unsupported
PPIVM (extension)
Painful Catch Sign
Difficulty with static positions
Step off
Apprehension Sign
Frequent muscle spasms
Lack of hypomobility
Gower’s Sign
Fear with movement
Segmental Hinging
Recurrent episodes
Reversal of Lumbopelvic Rhythm
Progressively worsening
Assessment to Diagnosis
Tests/Criteria with high +LR
+LR
>10
5-10
2-5
1-2
Shift in Probability
Large
Moderate
Small
Very small
(Diagnostic Accuracy)
History
Passive
Active
Age less than 40 (3.7)
Beighton Ligamentous Laxity Scale (2.5)
Prone Instability Test (1.7)
“Giving way” “Giving out” “Catching”
“Locking”
Avg SLR > 91o (3.3)
Aberrant Motions (1.6)
Temp. Relief with bracing
Passive Lumber Extension Test (8.8)
Total Flexion > 53o (1.3)
Self manipulator
Posterior Shear Test (1.1)
Total Extension > 26o
Pain with transitions
PAIVM (2.4)
Sit to stand test (infinite, selection bias)
Pain with sudden movement
PPIVM (flexion) (8.7, 95% CI: 0.6, 134.7)
Instability Catch Sign (1.8)
Difficulty sitting unsupported
PPIVM (extension) (7.1, 95% CI: 1.7, 29.2)
Painful Catch Sign (1.4)
Difficulty with static positions
Step off
Apprehension Sign (1.6)
Frequent muscle spasms
Lack of hypomobility with PA (5.0)
Gower’s Sign
Fear with movement (1.4)
Segmental Hinging
Recurrent episodes
Reversal of Lumbopelvic Rhythm
Progressively worsening
Assessment to Diagnosis
Tests/Criteria with high reliability
History
Passive
Active
Age less than 40
Beighton Ligamentous Laxity Scale
Prone Instability Test (k=0.69-0.87)
“Giving way” “Giving out” “Catching” “Locking”
Avg SLR > 91o
Aberrant Motion with Trunk Motion (k=0.07,0.60)
Temp. Relief with bracing
Passive Lumber Extension Test (high testretest reliability, however no k value)
Total Flexion > 53o
Self manipulator
Posterior Shear Test (k=0.27)
Total Extension > 26o
Pain with transitions
PAIVM hypermobile (k=0.48) hypo (k=0.38)
Sit to stand test
Pain with sudden movement
PPIVM (flexion) (-0.02, 0.26)
Instability Catch Sign
Difficulty sitting unsupported
PPIVM (extension) (-0.02, 0.26)
Painful Catch Sign
Difficulty with static positions
Step off
Apprehension Sign
Frequent muscle spasms
Lack of hypomobility with PA (k=0.30)
Gower’s Sign
Fear with movement
Segmental Hinging
Recurrent episodes
Reversal of Lumbopelvic Rhythm
Progressively worsening
Assessment to Diagnosis
Tests/Criteria Available (Multivariate)
 Hicks GE, Fritz JM, Delitto A, McGill SM. Preliminary development of a clinical prediction rule
for determining which patients with low back pain will respond to a stabilization exercise
program. Arch Phys Med Rehabil 2005;86:1753-1762.
Variables in the Clinical Prediction Rule
(CPR) for success with stabilization treatment
1. Age less than 40 y/o
2. (+) Prone Instability Test(k=0.69, 0.87)
3. (+) Aberrant Movements (k=0.07,0.60)
4. Avg SLR > 91o (ICC 0.87-0.96)
No. of Variables
Present
+LR
1 or more
1.3 (1.0-1.6)
2 or more
1.9 (1.2-2.9)
3 or more
4.0 (1.6-10.0)
•No reliability score available for 3 or more tests, however Kappa for PIT, SLR and
Aberrant Motions listed above.
•If Aberrant Movements are among the 3 tests, reliability would decrease significantly,
along with validity
Assessment to Diagnosis
Tests/Criteria Available (Multivariate)
 Hebert JJ, Koppenhaver SL, Magel JS, Fritz JM. The relationship of transversus abdominis and
lumbar multifidus activation and prognostic factors for clinical success with a stabilization
exercise program: a cross-sectional study. Arch Phys Med Rehabil 2010;91:78-85.
Predictors of clinical success with a
spinal stabilization exercise program
1. (+) Prone Instability Test (k=0.69, 0.87)
2. (+) Aberrant Movement (k=0.07,0.60)
3. Avg. SLR > 90o (ICC 0.87-0.96)
4. (+) Hypermobility with PA (k=0.30)
LM Activation
25.00%
20.00%
15.00%
10.00%
5.00%
0.00%
Mean LM
Activation
0
 # of prognostic factors = LM activation
 No relation between prognostic factors and TrA
 No Sn/Sp calculated, No LRs
1
2
3
No. + Prognostic Factors
4
The role of LM in spinal
stabilization is
controversial
Assessment to Diagnosis Summary
 The Passive Lumber Ext Test is not validated, however




comes the closest
General consensus of nearly all studies is that diagnosis
should not occur with one clinical test, but rather a
cluster of signs/tests
Does using multiple unreliable, inaccurate tests add
clarity?
Lack of correlation between radiographic findings and
clinical symptoms increases uncertainty
If a diagnosis can not reliably and accurately be
established, can there be agreement on treatment?
Validity of Clinical Instability
A
D
T
O
Are assessment protocols/tools available
to accurately/reliably diagnose clinical
instability?
Once clinical instability is diagnosed, is
there agreement on an established
treatment?
What is the best treatment for lumbar
instability?
Diagnosis to Treatment
Agreement on established treatment?
 Several studies agree
 “Stabilization exercise”
 “Stabilizing Exercise”
 “Trunk Muscle Stabilization Training”
 How this is carried out varies considerably
 Concentric, Eccentric, Isometric
 Muscle Firing, Sequencing, Patterning
 Position, Resistance, Reps
 Progression
 Feedback: US, EMG, Tactile, Visual
Diagnosis to Treatment
Agreement on established treatment?
 The most frequently cited study for exercise protocol:
Richardson CA, Jull GA. Muscle control – pain control. What exercises
would you prescribe? Manual Therapy 1995;1:2-10.
•Isometric co-contraction of the TrA and Multifidus with a static neutral spine
•Focus on precise muscle action with re-education of this contraction in:
•Quadriped
•Prone
•Upright positions
•Eventual functional training
Diagnosis to Treatment
Is Stabilization Exercise doing what we think it is?
 McGill et al. proposed that no single muscle is the best
stabilizer of the spine. Multiple muscles are required
dependent on the task.
 This muscle activation produces stability:


Muscles acting as ‘guywires’
Compression/Loading through antagonistic activity
• Stokes et al. : Analytical study of a biomechanical model
• Spinal Stability increased with increased intra-abdominal pressure (IAP)
• Forced component activation of abdominals decreased lumbar stability
• IAP generates an extension moment
• Can this extension moment inadvertently have an effect?
Diagnosis to Treatment Summary
Spinal Stabilization
Specific Muscle
Activation/Recruitment/Firing
Gross core activation
Intra-Abdominal Pressure
Other / All
A general
framework of
treatment
Validity of Clinical Instability
A
D
T
O
Are assessment protocols/tools available
to reliably diagnose clinical instability?
Once clinical instability is diagnosed, is
there agreement on an established
treatment?
What is the best treatment for lumbar
instability?
Treatment to Outcome
Diagnosed Radiographic Instability
 O’Sullivan (1997): …patients with CLBP and radiologic diagnosis of
spondylolysis or spondylolisthesis.
 Results: A “specific exercise” approach decreased pain/disability/pain medication
use significantly more than other commonly prescribed conservative treatment
programs in patients with chronically symptomatic
spondylolysis/spondylolisthesis.
 Kumar (2011):…patients with lumbar segmental instability.
 Results: Segmental stabilization exercise was more effective than placebo
intervention in symptomatic lumbar segmental instability.
 O’Sullivan (2011) Editorial:…’instability’ should be reserved solely for
‘unstable fractures’ and ‘unstable spondylolisthesis’.
Treatment to Outcome
Absence of Instability
 Koumantakis (2005): …patients with RCLBP and no clinical signs suggesting spinal
instability
 Conclusion: Stabilization exercises do not appear to provide additional benefit to patients
with subacute or CLBP who have no clinical signs suggesting the presence of spinal
instability
 Rachwitz (2006):…patients with acute, subacute and CLBP
 Conclusion: For LBP, segmental stabilizing exercises are more effective than treatment by
GP (walking, stretching, swimming, education, active rest, out of work, traction, STM), but
they are not more effective than other physiotherapy interventions.
 Macedo (2012):…patients with CLBP
 Conclusion: The results of this study suggest that motor control exercises and graded
activity have similar effects for patients with chronic nonspecific low back pain.
Recurrence
Hides JA, Jull GA, Richardson CA. Long-term effects of specific stabilizing
exercises for first-episode low back pain. Spine 2001;26:243-248
•1 and 3 year follow-up of exercise group (Richardson,Jull) vs. control
group after acute, first-episode LBP.
•1 year after treatment:
•specific exercise recurrence was 30%, control was 84%
•2-3 years after treatment:
•specific exercise recurrence was 35%, control was 75%
•Patients of both groups most commonly reported precipitating incidents of
recurrence related to lifting
•Lifting is a flexion-based movement
•DP was not ruled out initially
•Prevalence data shows that up to 90% of patient’s with acute LBP have a DP
Validity of Clinical Instability
A
D
T
O
Are assessment protocols/tools available
to accurately/reliably diagnose clinical
instability?
Once clinical instability is diagnosed, is
there agreement on an established
treatment?
What is the best treatment for lumbar
instability?
Cloudy ADTO
Linkage
Instability may be a
valid subgroup
Stabilization
Exercise may be
effective
 Where do I start?
 With the suspicion of instability (history)
Cook C, Brismee JM, Sizer PS. Subjective and objective descriptors of
clinical lumbar spine instability: a delphi study. Manual Therapy
2006;11:11-21
 122 PTs with OCS and/or FAAOMPT training responded fully to create a
consensus on the subjective and objective symptoms associated with
clinical instability of the spine.
 Ranked lists of subjective and object reports were created
Fritz (2005):…patients with LBP referred for flexion-extension radiographs
due to suspicion of lumbar instability
•Conclusion: Prevalence is much higher in this study (57%) compared to
other studies.
Top 10 subjective reports associated with clinical instability
1. Reports feeling of “giving way” or back “giving out”
2. Self manipulator who feels the need to frequently crack or pop the back
3. Frequent bouts or episodes of symptoms
4. History of painful catching or locking during twisting or bending of the
spine
5. Pain during transitional activities (e.g. sit to stand)
6. Greater pain returning to erect position from flexion
7. Pain increased with sudden, trivial, or mild movements
8. Difficulty with unsupported sitting and better with supported backrest
9. Worse with sustained postures and a decreased likelihood of reported
static position that is not painful
10. Condition is progressively worsening (e.g. shorter intervals between
bouts)
What Can I Do Monday?
 History that suggests instability, +/- radiographic diagnosis
 Catching / Locking / Giving out / Pain with sudden movements
 Rule out Directional Preference
 If DP can be ruled out, history suspicious of instability becomes more
relevant
 Perform tests, use criteria with the best available evidence (diagnostic
accuracy/reliability)
 Passive Lumbar Extension Test
 Age < 40 y/o
 Avg SLR > 91o
 Perform Lumbar Stabilization Exercise per Richardson and Jull
 Progress to patient specific functional limitations
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Thank You