Rehab med

• Common complication after stroke
• 50% of acute stroke survivors experienced dysphagia
• Incidence of dysphagia estimates range from 20% to 90%
• Complications of Dysphagia

  • Pneumonia
  • Dehydration
  • Malnutrition
• Dysphagia has traditionally been associated with brainstem and bilateral cerebral infarctions
• Left hemisphere 25% > right hemisphere lesions 15%
• Aspiration Pneumonia


  • Increased 3x in stroke survivors
  • 11-20 folds if confirmed
  • 2/3 patients of stroke survivors-silent aspiration
• Severity of Aspiration Pneumonia


  • Amount
  • Bacterial load
  • Acid content
  • Physical characteristics
• Malnutrition


  • 8% to 34% cases
  • Associated with poor outcome, prolonged hospital stay, numbers of complication
• Generally swallow function recovers after 7 days: > 1/2
• 11-13% persistent dysphagia after 6 months
• Prognosis factors


  • Medical status
  • Dysphagia
  • Rehabilitation potential
  • Severity of stroke
• Poor outcome-advanced age, impaired cognition, dependence on a wheelchair
• Intrinsic Tongue Muscles


  • Superior Longitudinal Muscle
  • Inferior Longitudinal Muscle
  • Vertical Muscle
  • Transverse Muscle

  
• • Innervates 2/3 of the tongue: Chorda tympani (branch of facial nerve)
  • Innervates 1/3 of the tongue: Glossopharyngeal nerve
• Pharyngeal Muscles


  • External circular layer (the constrictors)
  • Internal longitudinal layer
• External Circular Layer (The Constrictors)

  • Superior Constrictor
  • Middle Constrictor
  • Inferior Constrictor
• Difficulty swallowing (Dysphagia)


  Classic symptom of a surgical injury to the Vagus nerve in the neck
• Internal Longitudinal Layer


  • Palatopharyngeus
  • Salpingopharyngeus
  • Stylopharyngues
• Constrictors push food into the esophagus and constriction is under autonomic (Involuntary control)
• Palatopharyngeus, Salpingopharyngeus, Stylopharyngues raise the pharynx and larynx during swallowing and speaking
• Muscles of the Anterior Triangle

  • Suprahyoid
  • Infrahyoid
• Suprahyoid Muscles


  • Mylohyoid
  • Stylohyoid
  • Geniohyoid
  • Digastric
• Musculature of the Larynx

  • Extrinsic muscles (move the entire larynx)
  • Intrinsic muscles (move the small cartilages and vocal cords)
• Oral Preparatory Phase


  Stage I Transport: Food is propelled from the anterior to the posterior oral cavity
• Oral Propulsive Phase

  Stage II Transport: Tongue pushes upward and forward in the mouth, contacting the anterior portion of the hard palate

  
• Pharyngeal Phase


  1. Soft palate elevates and retracts with the pharyngeal wall to achieve a velopharyngeal seal

  2. Base of tongue retracts posteriorly to contact the posterior pharyngeal wall

  3. Pharyngeal wall contracts superiorly to inferiorly compressing the bolus to the esophagus
• Esophageal Phase


  1. Cricopharyngeus muscle relaxes

  2. Upper Esophageal Sphincter (UES) opening

  3. Tongue moves backward and downward

  4. Epiglottis inverts

  5. Pharyngeal constrictors contract sequentially with a peristaltic wave

  6. Passage of bolus into the esophagus

  7. Larynx opens

  8. UES closes

  9. Cricopharyngeus muscle contracts

  10. Esophageal clearance assisted by gravity and relaxation of the LES
• Tonic contraction of the lower esophageal sphincter (LES) and reflex esophageal swallowing prevents reflux of stomach contents
• Intrinsic Muscles of the Larynx

  • Transverse Arytenoid Muscle
  • Oblique Arytenoid Muscles
  • Thyroepiglottic Muscles
  • Lateral Cricoarytenoid Muscles
  • Posterior Cricoarytenoid Muscles
  • Thyroarytenoid Muscles
  • Cricothyroid Muscles
• • Lateral Cricoarytenoid Muscles are adductors of the vocal cords
  • Posterior Cricoarytenoid Muscles are abductors of the vocal cords
• Suprahyoid muscles elevate the hyoid bone and tongue during speech
• Infrahyoid Muscles


  • Thyrohyoid
  • Omohyoid
  • Sternohyoid
  • Sternothyroid
• Thyrohyoid muscle lowers the hyoid and larynx during phonation and swallowing
• Central Pattern Generator (CPG)

  • Dorsal group involved in triggering, shaping and timing of the sequential swallowing pattern
  • Ventral group distributes the swallowing drive to the various pools of motor neurons involved in swallowing
• Wallenberg Syndrome disrupts the swallowing CPG and can result in severe and long-standing dysphagia associated with aspiration
• Supramedullary Control of Swallowing

  • Right orbitofrontal cortex
  • Left mesial premotor cortex and cingulate
  • Right caudolateral sensorimotor cortex
  • Right anterior insula
  • Bilateral medial cerebellum
  • Bilateral Temporalpolar cortices
• Strongest activation has been seen in sensorimotor cortices, insula and cerebellum for voluntary initiation of swallowing

  
• Suprabulbar Palsy (SBP)


  • Dysphagia, Dysarthria, Dysphonia, Impairment of voluntary movements of tongue and facial muscles, Emotional lability
  • Most common cause is multiple bilateral lacunar infarcts
• Swallowing in the elderly: Dentition generally worsens, masticatory muscles weaken, strength of labial closure and tongue-palate pressure decreases, duration of transit from the oral cavity to the pharynx increases, decreased UES compliance and reduced hyolaryngeal elevation, increases the duration of swallow apnea