Head and neck musculoskeletal disorders Notes

NOTES NOTES HEAD & NECK MUSCULOSKELETAL DISORDERS GENERALLY, WHAT ARE THEY? PATHOLOGY & CAUSES ▪ Disorders of ligaments, muscles, tendons, bones inherent to head, neck SIGNS & SYMPTOMS ▪ Most commonly pain TREATMENT MEDICATIONS ▪ Anti-inflammatory/muscle relaxant SURGERY ▪ In refractory cases OTHER INTERVENTIONS DIAGNOSIS ▪ Physical therapy DIAGNOSTIC IMAGING ▪ For confirmation OTHER DIAGNOSTICS ▪ History, physical examination TEMPOROMANDIBULAR JOINT DYSFUNCTION osms.it/TMJ-dysfunction PATHOLOGY & CAUSES ▪ Category of conditions affecting jaw, producing pain and/or dysfunction centred around temporomandibular joint (TMJ) CAUSES ▪ Jaw clenching ▪ Teeth grinding (bruxism) 620 OSMOSIS.ORG ▪ ▪ ▪ ▪ ▫ Nocturnal/diurnal ▫ Commonly occurs with MDMA use Trauma ▫ Reactive oxygen species produced by inflammation → synovial fluid inflammation → cytokine production → TMJ destruction Arthritis Malocclusion/missing teeth Yawning → joint dislocation

Chapter 110 Head & Neck Disorders ▪ Associated diseases ▫ Rheumatoid arthritis (RA) ▫ Psychiatric disorders → major depressive disorder SIGNS & SYMPTOMS ▪ Pain: dull, constant ache; waxing, waning intensity (e.g. headaches, toothaches, earaches) ▫ Jaw movement exacerbates (e.g eating, talking) ▫ Manifests anywhere trigeminal nerve (cranial nerve V) innervates ▪ Jaw dysfunction → poor eating/talking ability ▪ Tinnitus ▪ Audible popping/clicking of joint DIAGNOSIS DIAGNOSTIC IMAGING Panoramic X-ray ▪ May reveal frank dislocation of mandible from TMJ TREATMENT MEDICATIONS ▪ Short-term NSAIDs ▪ Muscle relaxants second line (e.g. cyclobenzaprine) ▪ Benzodiazepines: nocturnal dosing → ↓ nocturnal bruxism SURGERY ▪ For refractory disorders ▫ Arthroscopy ▫ Individuals with underlying arthritis → synovial space bone fragment removal OTHER INTERVENTIONS ▪ Pain control ▫ Moist heat, cold compresses, massage, soft diet, avoid strain ▪ Habit adjustment ▫ ↓ pen chewing, change sleeping position, oral appliance use ▪ Physical therapy ▪ Dislocation → mandible reduction ▪ Bruxism causative → splinting OTHER DIAGNOSTICS History ▪ Bruxism ▪ Trauma Physical examination ▪ ↓ Range of motion ▪ Palpation ▫ Tenderness to examiner’s finger against TMJ when mouth open ▫ Clicking/popping heard/felt when jaw opened/closed ▪ Abnormal cranial nerve examination ▫ Likely trigeminal (CN V) symptom distribution → muscle weakness and/or sensory disturbance Figure 110.1 An MRI scan of the head in the parasagittal plane demonstrating an anteriorly dislocated disc in an individual reporting symptoms of temporomandibular joint dysfunction. OSMOSIS.ORG 621

TORTICOLLIS osms.it/torticollis PATHOLOGY & CAUSES ▪ Abnormal posturing of head, neck; various etiologies ▪ AKA cervical dystonia ▪ Sternocleidomastoid (SCM) muscle connect sternums, clavicle (muscle heads) to mastoid process ▪ One/both SCM head shortened/ hypertrophied → contralateral neck flexion, lateral rotation → torticollis TYPES Congenital ▪ Birthing difficulty → injury → fibroma/ hematoma formation of SCM muscle → abnormal posturing at/soon after birth ▪ Spinal abnormalities ▪ Klippel–Feil syndrome → cervical vertebrae fusion → torticollis ▪ Atlanto-occipital fusion → abnormal articulation/ankylosis of C1, occipital bone → torticollis Iatrogenic ▪ Side effect of dopamine agonist medication (e.g. first-generation antidepressants) Spasmodic ▪ AKA adult-onset/idiopathic ▪ Characterized by tonic/intermittent spasms of cervical muscles in adults COMPLICATIONS ▪ Permanent musculoskeletal defects ▪ Neurologic defects → spinal cord impingement 622 OSMOSIS.ORG SIGNS & SYMPTOMS ▪ Abnormal posturing of the head and neck ▫ Lateral rotation (laterocollis) ▫ Forward rotation (anterocollis) ▫ Backward rotation (retrocollis) ▪ SCM muscle ▫ Hypertrophied ▫ Nontender DIAGNOSIS OTHER DIAGNOSTICS ▪ Congenital ▫ Birth trauma/condition ▪ Iatrogenic ▫ Coincide with medication schedule/ change in dosing ▪ Spasmodic ▫ 5% have ⊕ family history ▫ ⅓ have other dystonias TREATMENT MEDICATIONS Congenital ▪ Muscular etiology → botulinum toxin injections ▫ Botulinum toxin → inhibits zinc endopeptidase → inhibition of neurotransmitter vesicle release → decreased muscle contraction → decreased muscle tone

Chapter 110 Head & Neck Disorders Iatrogenic ▪ Withdrawal/limitation of offending agent ▪ Prescription of a muscle relaxant/ antihistamine Spasmodic ▪ Muscle relaxant ▪ Benzodiazepines ▪ Anticholinergics ▫ Side effects → limited use (dry mouth, blurry vision, urinary retention, tachycardia, nausea, vomiting, anxiety) ▪ Botulinum toxin injections OTHER INTERVENTIONS Congenital ▪ Muscular etiology → passive neck stretching Spasmodic ▪ Massage ▪ Physical therapy ▪ Behavioral modification ▪ “Sensory trick” ▫ Sensory stimulus (e.g. lightly laying hand on cheek) may relieve muscle contraction SURGERY Congenital ▪ Vertebral etiology → surgical intervention if severe Spasmodic ▪ Refractory cases → surgical denervation of affected cervical musculature OSMOSIS.ORG 623