Muscles of the Larynx Flashcards
Intrinsic Muscles of the Larynx: Adductors: 1. 2. 3.
- LCA (lateral Cricoarytenoid
- Transverse Arytenoid
- Oblique Arytenoid
Intrinsic Laryngeal Muscle Functions: 1. 2. 3 . 4.
- Adductors
- Abductors
- Tensors
- Relaxers
Intrinsic Muscles of the Larynx:
Abductors:
1.
- PCA (Posterior Cricoarytenoid)
Intrinsic Muscles of the Larynx:
Tensors:
1.
2.
- Thyrovocalis (medial thyroarytenoid)
2. Cricothyroid
Intrinsic Muscles of the Larynx:
Relaxers:
1.
- Thyromuscularis (lateral thyroarytenoid)
Lateral Cricoarytenoid (LCA): Group: Origin: Insertion: Course: Function:
Group: Intrinsic Adductors
Origin: superior and lateral surface of cricoid
Insertion: muscular process of arytenoid
Course: superior and posterior
Function: Adduct vocal folds rotates arytenoids
Transverse Arytenoid: Group: Origin: Insertion: Course: Function:
Group: Intrinsic Adductors
Origin: lateral margin of posterior surface of one arytenoid
Insertion: lateral margin of posterior surface of opposite arytenoid
Course: Transverse
Function: Adduct; Brings arytenoids closer together glides arytenoids
Oblique Arytenoid: Group: Origin: Insertion: Course: Function:
Group: Intrinsic Adductors Origin: muscular process of arytenoid Insertion: apex of opposite arytenoid Course: oblique Function: adduct vocal folds; *glides* arytenoids
Posterior Cricoarytenoid: Group: Origin: Insertion: Course: Function:
Group: Intrinsic Abductors
Origin: cricoid lamina
Insertion: muscular process of each arytenoid
Course: oblique, fan-like
Function: Abduct vocal folds (open to breathe) rocking movement of Cricoarytenoid joint
Thyrovocalis (medial thyroarytenoid): Group: Origin: Insertion: Course: Function:
Group: Intrinsic Tensors Origin: inner surface of thyroid cartilage near angle at notch Insertion: vocal process of arytenoid Course: posterior Function: Tense (lengthen) vocal folds
Cricothyroid: Pars Recta Group: Origin: Insertion: Course: Function:
Group: Intrinsic Tensors Origin: cricoid arch Insertion: thyroid lamina Course: oblique and Superior Function: Tense (lengthen) vocal folds
Cricothyroid: Pars Oblique Group: Origin: Insertion: Course: Function:
Group: Intrinsic Tensors Origin: Lateral surface of cricoid Insertion: Juncture of thyroid lamina and inferior horn Course: oblique and superior Function: Tense (lengthen) vocal folds
Thyromuscularis (lateral thyroarytenoid): Group: Origin: Insertion: Course: Function:
Group: Intrinsic Relaxers
Origin: inner surface of thyroid cartilage at notch
Insertion: muscular process and base of arytenoid
Course: posterior
Function: Relax (shorten) vocal folds
Auxilliary Intrinsic Laryngeal Muscles:
Function:
1.
- Auxiliary (supplementary) function for voicing
Auxilliary Intrinsic Laryngeal Muscles:
1.
2.
3.
- Thyroepiglottis
- Superior Thyroarytenoid
- Aryepiglotticus
Styloid Process vs Mastoid Process
Styloid Process: close to ear canal, pointed projection
Mastoid Process: posterior to styloid process, rounded projection
Extrinsic Laryngeal Muscles:
Functions:
1.
2.
- Elevators
2. Depressors
Extrinsic Laryngeal Muscles, Elevators: 1. 2. 3. 4. 5. 6. 7. 8.
- Stylohyoid
- Mylohyoid
- Geniohyoid
- Hyoglossus
- Genioglossus
- Thyropharyngeus
- Digastricus Anterior
- Digastricus Posterior
* 2 of each, 16 total*
Stylohyoid: Group: Origin: Insertion: Course: Function:
Group: Extrinsic Elevators Origin: styloid process of temporal bone Insertion: corpus of hyoid Course: medial and inferior Function: elevate and retract hyoid
Mylohyoid: Group: Origin: Insertion: Course: Function:
Group: Extrinsic Elevators Origin: underside of mandible Insertion: corpus of hyoid Course: medial and inferior "fan-like" Function: elevate hyoid
Geniohyoid: Group: Origin: Insertion: Course: Function:
Group: Extrinsic Elevators Origin: inner surface of mandible near midline Insertion: corpus of hyoid Course: posterior Function: elevate hyoid
Hyoglossus: Group: Origin: Insertion: Course: Function:
Group: Extrinsic Elevators Origin: corpus and greater horns of hyoid Insertion: posterior and lateral tongue Course: superior Function: elevate hyoid
Genioglossus: Group: Origin: Insertion: Course: Function:
Group: Extrinsic Elevators Origin: inner surface of mandible at midline Insertion: corpus of hyoid and tongue Course: posterior Function: elevate hyoid
Thyropharyngeus: Group: Origin: Insertion: Course: Function:
Group: Extrinsic Elevators Origin: thyroid cartilage Insertion: posterior pharynx Course: lateral Function: elevate hyoid
Digastricus Anterior (Anterior Belly): Group: Origin: Insertion: Course: Function:
Group: Extrinsic Elevators
Origin: inner surface of mandible at midline
Insertion: intermediate tendon attached to hyoid
Course: posterior, inferior
Function: elevate hyoid (pull up and forward)
Digastricus Posterior (Posterior Belly): Group: Origin: Insertion: Course: Function:
Group: Extrinsic Elevators Origin: mastoid process of temporal bone Insertion: intermediate tendon Course: anterior and inferior Function: elevate hyoid (pull up and back)
Extrinsic Laryngeal Muscles, Depressors: 1. 2. 3. 4.
- Sternohyoid
- Omohyoid, superior and inferior bellies
- Sternothyroid
- Thyrohyoid
2 of each, 8 total
Sternohyoid: Group: Origin: Insertion: Course: Function:
Group: Extrinsic Depressors Origin: manubrium of sternum, medial end of clavicle Insertion: hyoid Course: superior Function: depress (lower) hyoid
Omohyoid Superior Belly: Group: Origin: Insertion: Course: Function:
Group: extrinsic depressors Origin: hyoid Insertion: intermediate tendon Course: down, inferior Function: depress hyoid
Sternothyroid: Group: Origin: Insertion: Course: Function:
Group: extrinsic depressors Origin: manubrium and rib 1 Insertion: thyroid lamina Course: superior Function: depress hyoid
Omohyoid Inferior Belly: Group: Origin: Insertion: Course: Function:
Group: extrinsic depressors Origin: scapula Insertion: intermediate tendon Course: anterior and superior Function: depress hyoid
Thyrohyoid: Group: Origin: Insertion: Course: Function:
Group: extrinsic depressors Origin: oblique line of thyroid cartilage Insertion: greater cornua of hyoid Course: superior Function: depress hyoid
Biologic Functions of Larynx:
1.
2.
3.
- Coughing
- Throat Clearing
- Abdominal Fixation
Biologic Functions of Larynx:
Coughing:
deep inhalation
followed by tensing and tight adduction of vocal folds and laryngeal elevation
in response to an irritant or foreign object
Biologic Functions of Larynx:
Throat Clearing:
less severe than cough, clears airway
Biologic Functions of Larynx:
Abdominal Fixation:
capture air in thorax, transfers force to muscles
ex: lifting
Non-Biologic Function of the Larynx:
1.
- Sound and voice production
Myoelastic Aerodynamic Theory of Vocal Fold Vibration:
For vocal folds to vibrate, there must be sufficient:
1.
2.
3.
- subglottal air pressure
- tissue elasticity
- air flow at constriction
Bernoulli’s Principle/Effect:
Given a constant flow of air at a point of constriction, there will be a decrease in air pressure perpendicular to the flow and an increase in the speed of the flow
Pressure at the vocal folds drops, resulting in air flow speed increasing which leads to vocal fold vibration when adducted.
Phases of Phonation
1.
2.
3.
- Vocal Attack (initiate)
- Sustained Phonation (continue)
- Terminate Phonation (terminate)
Vocal Attack Types:
1.
2.
3.
- Simultaneous Vocal Attack
- Breathy Vocal Attack
- Glottal Attack
Simultaneous Vocal Attack:
subglottal air pressure and vocal fold adduction occur at the same time
Gives good, clear quality
Breathy Vocal Attack:
exhaling through glottis before vocal fold adduction
Glottal Attack:
Exhalation after vocal fold adduction
vocal folds adducted and are forced open
Vertical Phase Difference:
Vocal folds open inferior to superior
Vocal folds close inferior to superior
A-P Phase Difference:
Vocal folds open posterior to anterior OPA
Vocal folds close anterior to posterior CAP
Medial Compression:
Force with which the vocal folds come together
Pitch/Fundamental Frequency:
Optimal:
Habitual:
Pitch changes:
Optimal: vocal folds vibrate at optimal frequency, no strain no tenstion
Ideally, habitual pitch = optimal pitch, but doesn’t always occur
Pitch changes: voice cracking, not consistent
Pitch/Fundamental Frequency:
Range:
how high and how low voice will go, determined by the length and weight of vocal folds
Fundamental Frequency for Adults
Males:
Females:
Males: 130 Hz
Females: 220 Hz (females have shorter, thinner vocal folds)
Frequency
Perceptual vs Objective
Perceptual: pitch (we measure pitch loudness and quality to determine if voice is working properly)
Objective: frequency
Intensty and Loudness
Perceptual vs Objective
Perceptual: loudness
Objective: Intensity, measured in dB
Intensity and loudness affected by:
1.
2.
- subglottal air pressure: must have atleast 3-5mm subglottal air pressure , higher = louder sound
- Medial Compression: greater = more subglottal air pressure require to speak
(vocal folds come together more tightly, more pressure needed to vibrate them)
Quality
Objective vs Perceptual
Only perceptual, too many factors to give one objective measurement
Can be breathy, rough, harsh, strained, etc.
What can the quality of the voice tell you about how it is functioning?
Age, gender, health status
Quality based on:
- longitudinal tension : how tense are vocal folds
- Mass per Unit Length (MLU): weight of vocal folds
- Medial Compression
- Subglottal Air Pressure
- Symmetry of vocal folds: will vibrate at different rates if not symmetrical, leading to voice disorder
Vocal Registers:
- Highest:
- Mid-High:
- Mid-Low:
- Lowest:
- Highest: Whistle( air flowing with high resistance)
Whisper (air flowing with low resistance) - Mid-High: Falsetto (most often used when laughing)
- Mid-Low: Modal (everyday register)
- Lowest: Glottal Fry : low subglottal air pressure, low tension, low frequency
What are the two unvoiced vocal registers?
Whistel and whisper, the highest registers
What is a vocal register?
The mode of vocal fold vibration