Whiplash Associated Disorders J. Scott Bainbridge, MD Denver Back Pain Specialists www.denverbackpainspecialists.com Definition Quebec Task Force on WhiplashAssociated-Disorders redefined the term in 1995 as “an acceleration-deceleration mechanism of energy transfer to the neck which may result from rear-end or side impact, predominately in MVAs, and from other mishaps. Definition The energy transfer may result in bony or soft tissue injuries (whiplash injury), which may in turn lead to a wide variety of clinical manifestations (whiplash Associated Disorders)”. WAD – Scope of Problem Yearly Incidence 4/1,000 (.8-8) $3.9 billion/yr in USA, $29 b w litigation 4-42% of pts w MVA related neck injuries with sx several yrs later Quebec Classification Grade 0: No neck c/o or PE signs Grade I: Neck c/o pain, stiffness or tenderness but no PE signs Grade II: Neck c/o AND mskl signs Grade III: Neck c/o AND neuro signs Grade IV: Neck c/o AND fracture or dislocation MVA – Spectrum Beyond WAD Cervicothoracic Other Musculoskeletal Brain Injury, Post Concussive Syndrome Other Neurological Vestibular Dysfunction Psychological Social/Economic/Litigation Motion Analysis of C-Spine During Whiplash Loading Kaneoka, et al; Spine 24:8 pp 763-770 10 males – sled glided back into damper at 4 km/hr Cineradiography of C-spine Each vertebra’s rotational angle and C5-6 instantaneous axes of rotation quantified SEMG of SCM and C-paraspinals Pathological Forces 8 km/hr 5 mph 135 N Pathology Facet: synovial fold (meniscoid) impingement, facet capsular subcatastrophic failure, capsular failure w/wo fracture or subluxation, microfracture – cart/bone Disc rim lesions/herniation, anterior vs. posterior Neural Muscular Start or speed degenerative cascade Degenerative Cascade Three Joint Complex – Two Zygapophyseal joints (facets joints) – Intervertebral disk pathologic changes in one part results in changes in other segments Kirkaldy-Willis Degenerative Cascade – Segmental Dysfunction reactive z-joint synovitis – Inflammation & joint pain Degenerative Cascade – Segmental Dysfunction articular cartilage zjoint degeneration Subchondral Sclerosis Cartilage Degeneration Degenerative Cascade – Instability Phase Annular fibers less competent Disc protrusions Uncovertebral Joints - Joints of Luschka Uncinate processes hook posterolaterally between one vertebra & the base of the next With shearing stresses to anular tissue, degenerative spurs begin to develop in teenage years Spurring can cause foraminal stenosis Degenerative Cascade – Instability Phase Normal Foraminal narrowing Degenerative Cascade – Stabilization Phase foraminal stenosis radiculopathy central spinal stenosis Degenerative Cascade – Stabilization Phase ankylosis of motion segment multilevel degenerative changes & spondylosis Degenerative Cascade – Stabilization Phase ankylosis of motion segment Cervical Z Joint Pain Prevalence of chronic cervical z-joint pain after whiplash injuries: 60% (Lord, Spine, 1996) Z Joint pain referral patterns characterized with provocative injections (Dwyer) Imaging is unremarkable Confirm suspicions with dx intraarticular z-jt injections or medial branch blockade Dwyer Z-joint Referral Patterns Spine 1990 Fukui Thoracic Z-joint Referral Patterns Regional Anesthesia 1997 HNP dura Spinal cord Lig. flavum “Annular fibers restrict axial rotation more than the facet joints.” (Krismer 1996) Posterior Tear with epidural leak Normal disc C2-3 C3-4 C4-5 C5-6 C6-7 Grubb, Kelly. Spine 25:13821389, 2000 Cervical Discography Pain Referral Patterns 173 discograms, 404 positive discs >50% with >3 positive discs C2-3 C3-4 C4-5 Provocative Cervical Discography Slipman NASS 2002 C5-6 C6-7 C7-T1 Provocative Cervical Discography Slipman NASS 2002 Treatment - Acute Oral Steroids? NSAIDs? Immobilize? Early Therapy? Treatment Facet Joints Treatment of Facet Injury Manual Therapy Postural Education Neuromuscular Reeducation/Stability Cervical Traction Spinal Injections Surgical Stabilization Manual Therapy Grade 1: Small amplitude, beginning range Grade 2: Large amp, resistance free Grade 3: Large amp into resistance (MET) Grade 4: Small amp well into resis (HVLA) Grade 5: Past end-range Spinal Injection/Nerve Ablation Intraarticular Corticosteroid Facet Denervation (Lord,et al; NEJM 1996; 335:1721-6) Treatment of Disk Disorders Posture/ Spine Stability Training Cervical Traction Treat Assoc Muscle/Facet Disorders Spinal Injections Surgical (ACDF, other); Treatment for axial neck pain? Surgical Intervention Neurological Compromise Axial Pain? Treatment of Muscle Disorders Massage: CMT, self, theracane Postural Educ Neuromuscular Reeducation/Stability Biofeedback Trigger Point Injections/Acupuncture Botulinum Toxin: Botox/Myoblock Movement Dysfunction Dynamic Stability and Muscle Balance of the Cervical Spine Segmental Dysfunction Movement Dysfunction loss of local or global control uncontrolled movement abnormal stress or strain dysfunction pain pathology Local stability segmental control The segmental stability of the spine is dependent on recruitment of the deep local stability muscles The spine will fail if local activity is insufficient even if the global muscles work strongly 1 –3 % MVC muscle stiffness significantly increases stability 25% MVC = optimal stiffness & stability (Cholewicki & McGill 1996, Crisco & Panjabi 1991, Hoffer & Andreasson 1981) Inhibition Inhibition: failure of normal recruitment – poor recruitment under low threshold stimulus – delayed recruitment timing – altered recruitment sequencing Inhibition ‘off’ Afferent Input & Recruitment Recruitment is partially due to the influence of proprioceptive activity Proprioceptive afferent (γ loop) input is essential for tonic (low threshold) recruitment Sensation of effort is linked to recruitment • (Eccles et al. 1957, Grimby & Hannerz 1976) Proprioception and Pathology Whiplash patients have significant in ability to reposition head after movement – worse with mid range movement than end range – worse in direction of injury mechanism (flex/ext) Kinesthetic accuracy improves with specific proprioceptive exercise (Loudow et al 1997, Revel et al 1991 1994, Heikkla & Astrom 1996) Evidence of Local Dysfunction Uncontrolled segmental translation Segmental change within cross-sectional area Altered pattern of low threshold recruitment Motor recruitment timing deficit • (review: Comerford & Mottram 2001) I. Control of Neutral low load recruitment in neutral Test for ability of anterior local stability muscles to control neutral (longus & RCAnt) Deep cervical flexor dysfunction Control WAD Can control greater range of 2mm Hg increments (up to 28 from baseline of 20) than WAD Less superficial muscle activity Can only control low increments (from baseline of 20 up to 23) Less consistent duration of hold More superficial muscle activity Jull 2000 Deep cervical flexor dysfunction identified in different pathological situations – Whiplash Associated Disorder (Jull 2000) – Post-concussional headache (Treleaven et al 1994) – Cervical headache (Watson & Trott 1993,Jull et al 1999) – Mechanical neck pain (Silverman et al 1991, White & Sahrmann 1994, Jull 1998) Dysfunction in Global Mobility System Myofascial shortening which limits physiological and / or accessory motion Overactive low load or low threshold recruitment Reacts to pain and pathology with spasm Dysfunction related to pathology Normal Able to hold head flexed and maintain position against light resistance Cervical pain cervical lordosis Inability to hold head flexed in supine – Lose position into chin poke & lordosis due to long weak longus cervicus that is compensated for by excessive scalenae and sterno-mastoid • (White & Sahrmann 1994) Relative Stiffness/Relative Flexibility (Sahrmann 2002) If 1 joint muscles lack ability to adequately shorten or are “weak” - they allow excessive motion If 2 joint muscles lack extensibility or are overactive- they limit normal motion which must be compensated for elsewhere in the movement system Dysfunction related to pathology Cervical discogenic pathology Normal Flex / ext ROM (18o) C5-6 C4-5 (17o) Translation C5-6 (3.2mm) C4-5 (3.2mm) (Dvorak 1988, White et al 1975) Abnormal Flex / ext ROM C5-6 (8o) C4-5 (23o) Translation C5-6 (1mm) C4-5 (6mm) (Singer et al 1983) Treatment Summary Dual approach: Treat the pathology Identify and correct the dynamic stability dysfunction which may precipitate pathology Control of neutral by integration of local stabilisers into global function Retrain dynamic control of the direction of stability dysfunction (especially rotation) Retrain tonic, through range control of the global stabilisers Actively regain extensibility of the global mobilisers ‘Alternative’ Approaches Tai Chi Alexander technique Yoga Pilates Physio ball (Swiss ball) Feldenkrais Treat Whole Person Psychology Work Family Secondary Gain Dynamics