Instability (Clinical/Radiographic)

Lumbar Instability (Clinical/Radiographic)Ryan Tauzell, MA, PT, Cert. MDT1DisclosuresNoneHistory1944Knuttson: Method of diagnosing segmental instability by measuring sagittal plane translation and rotation with lateral flexion/extension radiographs, then compared to normal rangesHistory1944Knuttson: Method of diagnosing segmental instability by measuring sagittal plane translation and rotation with lateral flexion/extension radiographs, then compared to normal rangesHistory1990White 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

1944History1990White 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

1944History1990Panjabi: presents a conceptual model of the spinal stabilization system, the neutral zone and clinical instability

19441992History1990Panjabi: presents a conceptual model of the spinal stabilization system, the neutral zone and clinical instability

19441992History1990Multiple studies on lumbar clinical instability and its role in LBP

How far have we come in nearly 70 years?

19441992TodayDefinitionsClinical 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 painStabilization System (3 Subsystems)VertebraeFacetsDiscsLigamentsMusclesTendonsCNSNervesFeedback System

The Stabilization System is divided into 3 subsystems that are in constant interaction. 11Subsystem Dysfunction?Compensatory response from other subsystems Response to Subsystem DysfunctionConceptual ResponseImmediate successful compensation from other subsystems

Long-term compensation from one or more subsystems

Injury to one or more subsystems

Conceptual Outcome

Normal Function

Normal function with altered stabilization system

Overall system dysfunction, LBP

DefinitionsClinical 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 painNeutral ZoneThat 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 laxityPortion of the range of motion that is highly flexible15Elastic ZoneThat part of the physiological intervertebral motion, measured from the end of the neutral zone up to the physiological limit.Zone of high stiffness/resistancePortion of the ROM that is highly stiff16Diagram of IV movement(Biely et al.)

High LaxityHigh ResistanceNeutral Zone + Elastic Zone = Physiological ROMZone ROM Weakness or InjuryZone ROM Strengthening, Osteophytes, FusionNeutral Zone may increase with injury or weakness and may decrease by strengthening, osteophyte formation and surgical fusion.17

Theoretical ConstructDefinitionsRadiographic Instability: No standardized definition

Radiographic Limitations

Lateral Flexion/Extension:No standardized procedure False positivesVariation in asymptomatic subjectsVariable limits for cutoff values to diagnose instabilitySlight variation in patient position of direction of beam can produce 10%-15% variation in displacement measureProvides no information about the active and neural componentsProvides no information on what is occurring within rangeCan not reliably correlate abnormal image to pain/disabilityClinical instability can exist without radiographic evidence of instability

A definition for radiographic instability in uncertain as is the measure of lateral flexion/extension radiograph due to several confounding factors. Therefore, the diagnosis of clinical instability can not solely be produced from imaging20Validity of Clinical InstabilityADTOSpratt KF, Weinstein JN. Chapter 25: Measuring clinical outcomes. In: Weisel S, ed. The Lumbar Spine. 2nd ed. v. 2. Philadelphia: W.B. Saunders Co., 1996:1313-1338PrevalenceDepending on the cutoff limits and the study12% 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)There is a wide range of prevalence dependent on assessment methods22Is 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 CLBPProspective cohort of 138 consecutive patients with RCLBP, Roland Morris and VAS scores obtainedSagittal angular rotation and translation of each lumbar segment was measured on radiograph then compared to reference range derived from a study of 30 asymptomatic volunteersLumbar Segmental Mobility Disorder (LSMD) defined as 2sd from reference meanNormal reference intervals developed using 2 models (Gaussian, novel normalized within-subjects)Rotational Instability: 23%Translational Instability: 32%Radiographic metholody was identical for symptomatic and asymptomatic groups with high reliability23Is 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 LSMDsShort answer: NO. +/- LSMDs, pain/disability is the same within the black box of NSLBP24Assessment to DiagnosisAbdullah et al. Clinical Test to Diagnose Lumbar Segmental Instability: A Systematic ReviewHicks et al. Interrater Reliability of Clinical Examination Measures for Identification of Lumbar Segmental InstabilityHicks et al. Preliminary Development of a Clinical Prediction Rule for Determining Which Patients With LBP Will Repsond to a Stabilization Exercise ProgramAbbott et al. Lumbar Segemental Mobility Disorders: Comparison of Two Methods of Defining Abnormal Displacement Kinematics in a Cohort of Patients with NSLBPDemoulin et al. Lumbar Functional Instability: A Critical Appraisal of the LiteratureFritz et al. Accuracy of the Clinical Examination to Predict Radiographic Instability of the Lumbar SpineAbbott et al. Lumbar Segmental Instability: A Criterion-Related Validity Study of Manual Therapy AssessmentCook et al. Subjective and Objective Descriptors of Clinical Lumbar Spine Instability: A Delphi StudyKasai et al. A New Evaluation Method for Lumbar Spinal Instability: Passive Lumbar Extension TestIn an attempt to answer the question of consistently accurate diagnostics, I reviewed several studies25Study MixProspective Cohorts: 5Single group repeated measure interrater reliability study: 1Critical Appraisal of Literature: 1Delphi Study: 1Systematic Review: 1Assessment to DiagnosisTests/Criteria AvailableHistoryPassiveActiveAge less than 40Beighton Ligamentous Laxity Scale Prone Instability Test Giving way Giving out Catching LockingAvg SLR > 91oAberrant Motions Temp. Relief with bracingPassive Lumber Extension TestTotal Flexion > 53oSelf manipulatorPosterior Shear Test Total Extension > 26oPain with transitionsPAIVM Sit to stand testPain with sudden movementPPIVM (flexion) Instability Catch SignDifficulty sitting unsupportedPPIVM (extension) Painful Catch Sign Difficulty with static positionsStep off Apprehension Sign Frequent muscle spasmsLack of hypomobilityGowers SignFear with movementSegmental HingingRecurrent episodesReversal of Lumbopelvic RhythmProgressively worseningAssessment to DiagnosisTests/Criteria with high +LR(Diagnostic Accuracy)HistoryPassiveActiveAge less than 40 (3.7)Beighton Ligamentous Laxity Scale (2.5)Prone Instability Test (1.7)Giving way Giving out Catching LockingAvg SLR > 91o (3.3)Aberrant Motions (1.6)Temp. Relief with bracingPassive Lumber Extension Test (8.8)Total Flexion > 53o (1.3)Self manipulatorPosterior Shear Test (1.1)Total Extension > 26oPain with transitionsPAIVM (2.4)Sit to stand test (infinite, selection bias)Pain with sudden movementPPIVM (flexion) (8.7, 95% CI: 0.6, 134.7)Instability Catch Sign (1.8)Difficulty sitting unsupportedPPIVM (extension) (7.1, 95% CI: 1.7, 29.2)Painful Catch Sign (1.4)Difficulty with static positionsStep off Apprehension Sign (1.6)Frequent muscle spasmsLack of hypomobility with PA (5.0)Gowers SignFear with movement (1.4)Segmental HingingRecurrent episodesReversal of Lumbopelvic RhythmProgressively worsening+LRShift in Probability>10Large5-10Moderate2-5Small1-2Very smallWide CI indicates imprecision in the estimate 28Assessment to DiagnosisTests/Criteria with high reliabilityHistoryPassiveActiveAge less than 40Beighton Ligamentous Laxity ScaleProne Instability Test (k=0.69-0.87)Giving way Giving out Catching LockingAvg SLR > 91oAberrant Motion with Trunk Motion (k=-0.07,0.60)Temp. Relief with bracingPassive Lumber Extension Test (high test-retest reliability, however no k value)Total Flexion > 53oSelf manipulatorPosterior Shear Test (k=0.27)Total Extension > 26oPain with transitionsPAIVM hypermobile (k=0.48) hypo (k=0.38)Sit to stand testPain with sudden movementPPIVM (flexion) (-0.02, 0.26)Instability Catch SignDifficulty sitting unsupportedPPIVM (extension) (-0.02, 0.26)Painful Catch SignDifficulty with static positionsStep off Apprehension SignFrequent muscle spasmsLack of hypomobility with PA (k=0.30)Gowers SignFear with movementSegmental HingingRecurrent episodesReversal of Lumbopelvic RhythmProgressively worsening29Assessment to DiagnosisTests/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 treatmentAge less than 40 y/o(+) Prone Instability Test(k=0.69, 0.87)(+) Aberrant Movements (k=0.07,0.60)Avg SLR > 91o (ICC 0.87-0.96)

No. of Variables Present+LR1 or more1.3 (1.0-1.6)2 or more1.9 (1.2-2.9)3 or more4.0 (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 validityAssessment to DiagnosisTests/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(+) Prone Instability Test (k=0.69, 0.87)(+) Aberrant Movement (k=0.07,0.60)Avg. SLR > 90o (ICC 0.87-0.96)(+) Hypermobility with PA (k=0.30)

# of prognostic factors = LM activationNo relation between prognostic factors and TrANo Sn/Sp calculated, No LRs

No. + Prognostic FactorsThe role of LM in spinal stabilization is controversial31Assessment to Diagnosis SummaryThe Passive Lumber Ext Test is not validated, however comes the closestGeneral consensus of nearly all studies is that diagnosis should not occur with one clinical test, but rather a cluster of signs/testsDoes using multiple unreliable, inaccurate tests add clarity?Lack of correlation between radiographic findings and clinical symptoms increases uncertaintyIf a diagnosis can not reliably and accurately be established, can there be agreement on treatment?

Validity of Clinical InstabilityADTODiagnosis to TreatmentAgreement on established treatment?Several studies agree Stabilization exerciseStabilizing ExerciseTrunk Muscle Stabilization Training

How this is carried out varies considerably Concentric, Eccentric, IsometricMuscle Firing, Sequencing, PatterningPosition, Resistance, RepsProgressionFeedback: US, EMG, Tactile, Visual

Diagnosis to TreatmentAgreement 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 spineFocus on precise muscle action with re-education of this contraction in:QuadripedProneUpright positionsEventual functional trainingDiagnosis to TreatmentIs 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 modelSpinal Stability increased with increased intra-abdominal pressure (IAP)Forced component activation of abdominals decreased lumbar stability IAP generates an extension momentCan this extension moment inadvertently have an effect?

Diagnosis to Treatment SummarySpinal StabilizationSpecific Muscle Activation/Recruitment/FiringGross core activation Intra-Abdominal PressureOther / AllA general framework of treatmentValidity of Clinical InstabilityADTOTreatment to OutcomeDiagnosed Radiographic InstabilityOSullivan (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.

OSullivan (2011) Editorial:instability should be reserved solely for unstable fractures and unstable spondylolisthesis.

Lets look at the outcome of a matching treatment to diagnosed instability or suspicion of instability. Subgrouping the subject population improved the outcome of the matched treatment39Koumantakis (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 CLBPConclusion: 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 CLBPConclusion: The results of this study suggest that motor control exercises and graded activity have similar effects for patients with chronic nonspecific low back pain.

Treatment to OutcomeAbsence of Instability40RecurrenceHides JA, Jull GA, Richardson CA. Long-term effects of specific stabilizing exercises for first-episode low back pain. Spine 2001;26:243-2481 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 liftingLifting is a flexion-based movementDP was not ruled out initiallyPrevalence data shows that up to 90% of patients with acute LBP have a DPHides and others did a follow-up study to the original 1996 study to document the the natural course of LM recovery and the effectiveness of specific exercise on muscle recovery41Validity of Clinical InstabilityADTO

Stabilization Exercise may be effectiveCloudy ADTO LinkageInstability may be a valid subgroupWhere 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 instabilityConclusion: Prevalence is much higher in this study (57%) compared to other studies.Reports feeling of giving way or back giving outSelf manipulator who feels the need to frequently crack or pop the backFrequent bouts or episodes of symptomsHistory of painful catching or locking during twisting or bending of the spinePain during transitional activities (e.g. sit to stand)Greater pain returning to erect position from flexionPain increased with sudden, trivial, or mild movementsDifficulty with unsupported sitting and better with supported backrestWorse with sustained postures and a decreased likelihood of reported static position that is not painfulCondition is progressively worsening (e.g. shorter intervals between bouts)Top 10 subjective reports associated with clinical instabilityWhat Can I Do Monday?History that suggests instability, +/- radiographic diagnosisCatching / Locking / Giving out / Pain with sudden movementsRule out Directional Preference If DP can be ruled out, history suspicious of instability becomes more relevantPerform tests, use criteria with the best available evidence (diagnostic accuracy/reliability)Passive Lumbar Extension TestAge < 40 y/oAvg SLR > 91o

Perform Lumbar Stabilization Exercise per Richardson and Jull Progress to patient specific functional limitations

ReferencesNizard RS, Wybler M, Laredo JD. Radiologic assessment of lumbar intervertebral instability and degenerative spondylolisthesis. Radiol Clin North Am 2001;39:55-71Cook C, Brismee JM, Sizer PS, Jr. Subjective and objective descriptors of clinical lumbar spine instability: a Delphi study. Manual Therapy 2006;11:11-21Hides JA, Richardson CA, Jull G. Multifidus muscle recovery is not automatic after resolution of acute, first-episode low back pain. Spine 1996;21:2763-2769Hides JA, Jull GA, Richardson CA. Long-term effects of specific stabilizing exercises for first-episode low back pain. Spine 2001;26:E243-E248Fritz 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. DOI:10.1007/s00586-004=0803-4OSullivan PB, Twomey LT, Allison GT. Evaluation of specific stabilizing exercise in the treatment of chronic low back pain with radiologic diagnosis of spondylolysis or spondylolisthesis. Spine 1997;22:2959-2967Kumar SP. Efficacy of segmental stabilization exercises for lumbar segmental instability in patients with mechanical low back pain: a randomized placebo controlled crossover study. N Am J Med Sci 2011;3:456-461. doi: 10.4297/najms.2011.3456Koumantakis GA, Watson PJ, Oldham JA. Trunk muscle stabilization training plus general exercise versus general exercise only: randomized controlled trial of patients with recurrent low back pain. Physical Therapy 2005;85:209-225.OSullivan P. (Editorial) Its time for change wit h the management of non-specific chronic low back pain. Br J Sports Med 2011. doi:10.1136/bjsm.2010.081638Hicks 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;86:1753-1762McGill SM, Grenier S, Kavcic N, Cholewicki J. Coordination of muscle activity to assure stability of the lumbar spine. Journal of Electromyography and Kinesiology 2003;13:353-359Wallwork TL, Stanton WR, Freke M, Hides JA. The effect of chronic low back pain on size and contraction of the lumbar multifidus muscle. Manual Therapy 2009;14:496-500Biely S, Smith SS, Silfies SP. Clincial instability of the lumbar spine: diagnosis and intervention. Orthopaedic Practice 2006;18:11-18Cook C, Brismee JM, Sizer PS. Subjective and objective descriptors of clinical lumbar spine instability: a delphi study. Manual Therapy 2006;11:11-21Richardson CA, Jull GA. Muscle control-pain control. What exercises would you prescribe? Manual Therapy 1995;1:2-10Stokes IAF, Gardner-Morse MG, Henry SM. Abdominal muscle activation increases lumbar spinal stability: analysis of contributions of different muscle groups. Clin Biomech 2011;26:797-803Alqarni AM, Schneiders AG, Hendrick PA. Clinical tests to diagnose lumbar segmental instability: a systematic review. JOSPT 2011;41:130-140Demoulin C, Destree V, Tomasella M, Crielaard JM, Vanderthommen M. Lumbar functional instability: a critical appraisal of the literature. Annales de Readaptation et de Medecine Physique 2007;50:677-684Abbott JH, Fritz JM, McCane B, Shultz B, Herbison P, Lyons B, Stenfanko, Walsh RM. Lumbar segmental mobility disorders:comparison of two methods of defining abnormal displacement kinematics in a cohort of patients with non-specific mechanical low back pain. BMC Musculoskeletal Disorders 2006;7:1-11. doi:10.1186/1471-2474-7-45Kasai Y, Morishita K, Kawakita E, Kondo T, Uchida A. A new evaluation method for lumbar spinal instability: passive lumbar extension test. Physical Therapy 2006;86:1661-1667

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Thank You49