The Muscular System. Part A

Transcription

1 The Muscular System Part A 10

2 The Muscular System Part A 10

3 Hold onto your glutes, this is a big one. 10

4 Interactions of Skeletal Muscles Skeletal muscles work together or in opposition Muscles only pull (never push) As muscles shorten, the insertion generally moves toward the origin Whatever a muscle (or group of muscles) does, another muscle (or group) undoes

5 Muscle Classification: Functional Groups Prime movers provide the major force for producing a specific movement Antagonists oppose or reverse a particular movement Synergists Add force to a movement Reduce undesirable or unnecessary movement Fixators synergists that immobilize a bone or muscle s origin

6 Naming Skeletal Muscles I call this one Betty

7 Naming Skeletal Muscles Location of muscle bone or body region associated with the muscle Rectus Abdominus

8 Naming Skeletal Muscles Shape of muscle e.g., the deltoid muscle (deltoid = triangle)

9 Naming Skeletal Muscles Relative size e.g., maximus (largest), minimus (smallest), longus (long) Gluteus Maximus

10 Naming Skeletal Muscles Direction of fibers e.g., rectus (fibers run straight), transversus, and oblique (fibers run at angles to an imaginary defined axis)

11 Naming Skeletal Muscles Number of origins e.g., biceps (two origins) and triceps (three origins) Triceps Brachii = A long, a lateral and A medial origin

12 Naming Skeletal Muscles Cause this is the occiput Location of attachments named according to point of origin or insertion

13 Naming Skeletal Muscles Action e.g., flexor or extensor, as in the names of muscles that flex or extend, respectively

14 Major Skeletal Muscles: Anterior View The 48 superficial muscles and the diaphragm here are divided into 11 regional areas of the body (definitely know all of these + thenar, hypothenar and extrinsic eye) Head Temporalis Masseter Shoulder Trapezius Deltoid Arm Triceps brachii Biceps brachii Brachialis Forearm Pronator teres Brachioradialis Flexor carpi radialis Palmaris longus Flexor digit superficialis Pelvis/thigh Iliopsoas Pectineus Thigh Rectus femoris Vastus lateralis Vastus medialis Leg Fibularis longus Extensor digitorum longus Tibialis anterior Extensor halluces longus Facial Levator labii sup/inf Levator/depressor anguli oris Epicranius, frontal belly Orbicularis oculi Zygomaticus major/minor Orbicularis oris Neck Platysma Sternocleidomastoid Thorax Coracobrachialis Subscapularis Pectoralis minor Serratus anterior Pectoralis major Intercostals and diaphragm Abdomen Rectus abdominis Internal oblique Transversus abdominis External oblique Thigh Tensor fasciae latae Sartorius Adductor longus Gracilis Leg Gastrocnemius Soleus

15 Major Skeletal Muscles: Posterior View The 28 superficial muscles here are divided into 7 regional areas of the body (definitely know all of these +, again, thenar, hypothenar and extrinsic eye) Opponens digiti minimi Flexor digiti minimi brevis Abductor digiti minimi Arm Flexor pollicis brevis Triceps brachii Brachialis Forearm Brachioradialis Extensor carpi radialis longus/brevis Flexor carpi ulnaris Extensor carpi ulnaris Abductor pollicis brevis Extensor digitorum Opponens pollicis Iliotibial tract Leg Gastrocnemius Soleus Fibularis longus Calcaneal (Achilles) tendon Neck Epicranius, occipital belly Sternocleidomastoid Trapezius Shoulder Deltoid Infra/supraspinatus Teres major/minor Rhomboid major Latissimus dorsi Hip Thigh Gluteus medius Gluteus maximus Adductor magnus Hamstrings: Biceps femoris Semitendinosus Semimembranosus 89 total

16 Only 165 slides to go in this chapter covering almost every muscle in the body from the smallest eye muscle to the largest thigh muscle. If you haven t started studying yet, tonight would be a very good time.

17 Muscles: Name, O/I, Action, and Innervation Name and description of the muscle be alert to information given in the name (ie, temporalis) Origin and insertion there is always a joint between the origin and insertion Action best learned by acting out a muscle s movement on one s own body (OK, everyone test the fibularis longus right now) Nerve supply name of major nerve that innervates the muscle

18 Muscles of the Scalp Here s the first one. Let s see if you can wrap your head around this one.

19 Muscles of the Scalp Epicranius (occipitofrontalis) bipartite muscle consisting of the: Frontalis & Occipitalis & Galea aponeurotica cranial aponeurosis connecting above muscles These two muscles have alternate actions of pulling the scalp forward and backward

20 Muscles of the Scalp Facial nerve

21 Muscles of the Scalp Epicranius Galea aponeurotica Frontal belly Occipital belly Facial nerve

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23 Muscles of the Face 11 muscles are involved in lifting the eyebrows, flaring the nostrils, opening and closing the eyes and mouth, and smiling All are innervated by cranial nerve VII (facial nerve) Pretty Face Japanese author Yasuhiro Kano Usually insert in skin (rather than bone), and adjacent muscles often fuse

24 Muscles of the Face Corrugator supercilii Orbicularis oculi Levator labii superioris Zygomaticus minor and major Buccinator Risorius Orbicularis oris Mentalis Depressor labii inferioris Depressor anguli oris Platysma

25 Yes, sorry, you just have to commit them to memory. Here s a sample question from the test The muscles of facial expression are innervated by a) cranial nerve III b) cranial nerve XII c) cranial nerve VII d) cranial nerve V

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28 Muscles of Mastication There are four pairs of muscles involved in mastication (chewing your food) Prime movers temporalis and masseter Grinding movements 2 pterygoids All are innervated by cranial nerve V (trigeminal nerve)

29 Muscles of Mastication All four are Trigeminal nerve, CN V Temporalis Masseter Under masseter

30 Muscles of Mastication Lateral pterygoid Medial pterygoid Masseter pulled away These are Trigeminal nerve, CN V

31 Extrinsic Tongue Muscles Three major muscles that anchor and move the tongue All are innervated by cranial nerve XII (hypoglossal nerve)

32 Extrinsic Tongue Muscles Cranial nerve XII (hypo-glossal nerve) For all the glossus muscles Tongue Genioglossus Mandibular symphysis Geniohyoid Thyroid cartilage Styloid process Styloglossus Hyoglossus Stylohyoid Hyoid bone Thyrohyoid

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34 But, that s it for the easy innervations: The next bunch have 7 different innervations

35 Muscles of the Anterior Neck and Throat: Suprahyoid Four deep throat muscles Form the floor of the oral cavity Anchor the tongue Elevate the hyoid (suprahyoid, they only pull, so, these must elevate) Move the larynx superiorly during swallowing

36 Muscles of the Anterior Neck and Throat: Suprahyoid Digastric Anterior belly Posterior belly Mylohyoid Stylohyoid Hyoid bone And, a geniohyoid which is deep to the mylohyoid

37 Muscles of the Anterior Neck and Throat: Suprahyoid Hyoid bone Mylohyoid (cut) Geniohyoid

38 But,,,,,,,,

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40 Muscles of the Anterior Neck and Throat: Infrahyoid Straplike muscles that depress the hyoid and larynx during swallowing and speaking

41 Muscles of the Anterior Neck and Throat: Infrahyoid Thyrohyoid Omohyoid (superior belly) Sternohyoid Sternothyroid Omohyoid (inferior belly) But, again

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43 Muscles of the Neck: Head Movements

44 Muscles of the Neck: Head Movements Major head flexor is the sternocleidomastoid Lateral head movements are accomplished by the sternocleidomastoid and scalene muscles Head extension is accomplished by the deep splenius muscles and aided by the superficial trapezius

45 Muscles of the Neck: Head Movements 1st cervical vertebra Sternocleidomastoid Base of occipital bone Mastoid process Middle scalene Anterior scalene Posterior scalene (a) Anterior

46 Muscles of the Neck: Head Movements Mastoid process Splenius capitis Spinous processes of the vertebrae Splenius cervicis (b) Posterior

47 Muscles of the Neck: Head Movements Trapezius

48 Muscles of the Neck: Head Movements Flexion and lateral flexion

49 Trunk Movements: Deep Back Muscles

50 Trunk Movements: Deep Back Muscles The prime mover of back extension is the erector spinae Erector spinae, or sacrospinalis, muscles consist of three columns on each side of the vertebrae iliocostalis, longissimus, and spinalis Lateral bending of the back is accomplished by unilateral contraction of these muscles Other deep back extensors include the semispinalis muscles and the quadratus lumborum

51 Trunk Movements: Deep Back Muscles Mastoid process of temporal bone Longissimus capitis Iliocostalis cervicis Longissimus cervicis Iliocostalis thoracis Longissimus thoracis Spinalis thoracis Erector spinae Iliocostalis lumborum External oblique Iliocostalis Longissimus Spinalis Semispinalis capitis Semispinalis cervicis Semispinalis thoracis Multifidus Quadratus lumborum (d)

52 Trunk Movements: Deep Back Muscles

53 Trunk Movements: Deep Back Muscles

54 Trunk Movements: Short Muscles Four short muscles extend from one vertebra to another These muscles are synergists in extension and rotation of the spine Not in the table Nor this O = origin I = insertion Intertransversarius Rotatores Multifidus Interspinales (e)

55 Muscles of Respiration - Ribs The only thing I could think of was the BBQ ribs and I already did that.

56 Muscles of Respiration The primary function of deep thoracic muscles is to promote movement for breathing External intercostal External intercostals more superficial layer that lifts the rib cage and increases thoracic volume to allow inspiration (a)

57 Muscles of Respiration - Intercostals Internal intercostals deeper layer that aids in forced expiration Internal intercostal

58 Muscles of Respiration - Intercostals Diaphragm most important muscle in inspiration

59 Muscles of Respiration: The Diaphragm Foramen for inferior vena cava Central tendon of diaphragm Xiphoid process of sternum Foramen for esophagus Costal cartilage Diaphragm Foramen for aorta 12th rib Lumbar vertebra Quadratus lumborum Psoas major

60 Muscles of Respiration: The Diaphragm Central tendon of diaphragm Body of thoracic vertebra Aorta Diaphragm (muscular part) Inferior vena cava Esophagus Pericardial sac Pericardium (cut)

61 Muscles of Respiration: Table

62 Muscles of the Abdominal Wall

63 Muscles of the Abdominal Wall

64 Muscles of the Abdominal Wall The abdominal wall is composed of four paired muscles (internal and external obliques, transversus abdominis, and rectus abdominis), their fasciae, and their aponeuroses Fascicles of these muscles run at right and oblique angles to one another, giving the abdominal wall added strength

65 Muscles of the Abdominal Wall - continue In addition to forming the abdominal wall, these muscles: Are involved with lateral flexion and rotation of the trunk Help promote urination, defecation, childbirth, vomiting, coughing, and screaming(sneezing, spitting, tackling, hitting a baseball, throwing, running, driving, getting out of bed, getting into bed )

66 Muscles of the Abdominal Wall Transversus abdominis Internal oblique External oblique Tendinous intersection Rectus abdominis Aponeurosis of the external oblique (a) Inguinal ligament (formed by free inferior border of the external oblique aponeurosis)

67 Muscles of the Abdominal Wall Linea alba Linea alba Not to be confused with. Figure 10.11a

68 Muscles of the Abdominal Wall Jessica Alba

69 Muscles of the Abdominal Wall - continue External oblique IIiac crest Rectus abdominis Internal oblique Pubic tubercle Lumbar fascia Transversus abdominis Lumbar fascia Inguinal ligament (b)

70 Muscles of the Abdominal Wall - continue Transversus abdominis External oblique Aponeuroses (c) Peritoneum Linea alba Again, not. Rectus abdominis Internal oblique Skin

71 Table

72 Extrinsic Shoulder Muscles

73 Extrinsic Shoulder Muscles

74 Extrinsic Shoulder Muscles Muscles of the thorax Anterior: pectoralis major, pectoralis minor, serratus anterior, and subclavius Posterior: latissimus dorsi, trapezius muscles, levator scapulae, and rhomboids These muscles are involved with the movements of the scapula including elevation, depression, rotation, and lateral and medial movements Prime movers of shoulder elevation are the trapezius and levator scapulae

75 Extrinsic Shoulder Muscles Subclavius Clavicle Deltoid Pectoralis major Sternum Subscapularis Pectoralis minor Coracobrachialis Serratus anterior Humerus

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77 Extrinsic Shoulder Muscles Muscles of the thorax Posterior: latissimus dorsi, trapezius muscles, levator scapulae, and rhomboids These muscles are involved with the movements of the scapula including elevation, depression, rotation, and lateral and medial movements Prime movers of shoulder elevation are the trapezius and levator scapulae

78 Extrinsic Shoulder Muscles Levator scapulae Trapezius Deltoid Rhomboid minor Rhomboid major Supraspinatus Clavicle Spine of scapula Infraspinatus Teres minor Teres major Humerus Latissimus dorsi (c)

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80 Muscles Crossing the Shoulder Nine muscles cross the shoulder joint and insert into the humerus Prime movers include: Pectoralis major arm flexion Latissimus dorsi and posterior fibers of the deltoid arm extension Middle fibers of the deltoid arm abduction

81 Muscles Crossing the Shoulder Clavicle Deltoid Sternum Pectoralis major Latissimus dorsi (a) Anterior view (b) Posterior view

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84 Muscles Crossing the Shoulder Rotator cuff muscles supraspinatus, infraspinatus, teres minor, and subscapularis SITS Function mainly to reinforce the capsule of the shoulder Secondarily act as synergists and fixators

85 Muscles Crossing the Shoulder Supraspinatus Infraspinatus Teres minor Subscapularis

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87 Muscles Crossing the Shoulder The teres major: Act as a synergist Does not contribute to reinforcement of the shoulder joint, not a rotator cuff SITS muscle

88 Muscles Crossing the Shoulder Teres major

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90 Muscles Crossing the Elbow

91 Muscles Crossing the Elbow Forearm extension The triceps brachii is the prime mover of forearm extension

92 Muscles Crossing the Elbow Triceps brachii: Lateral head Long head

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94 Muscles Crossing the Elbow Forearm flexion Brachialis and biceps brachii are the chief forearm flexors

95 Muscles Crossing the Shoulder Biceps brachii Long head Short head Biceps brachii Brachialis Brachialis

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97 Muscles of the Forearm There are a lot of them. Yes, you have to know them.

98 Muscles of the Forearm The two functional forearm muscle groups are: those that cause wrist movement, and those that move the fingers and the thumb These muscles insert via strong ligaments which pass under the flexor and extensor retinacula Most anterior muscles are flexors, and posterior muscles are extensors The pronator teres and pronator quadratus are not flexors, but pronate the forearm The supinator muscle is a synergist with the biceps brachii in supinating the forearm

99 Muscles of the Forearm: Anterior Compartment These muscles are primarily flexors of the wrist and fingers Palmar aponeurosis Flexor retinaculum Flexor digitorum superficialis Flexor carpi ulnaris Palmaris longus Flexor carpi radialis Medial epicondyle of humerus Brachioradialis Pronator teres

100 Table

101 There are some unspecified, as yet unidentified muscles

102 Flexible Politicus Longus

103 Flexible Politicus Longus

104 Mudwater Quadratus

105 Mudwater Quadratus

106 Muscles of the Forearm: Posterior Compartment These muscles are primarily extensors of the wrist and fingers Extensor digitorum Extensor carpi radialis brevis Extensor indicis Extensor digiti minimi Extensor carpi ulnaris Flexor carpi ulnaris Extensor carpi radialis longus (a)

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108 More undiscovered muscles Extensor Carp Radials Longus and Brevis

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110 Not this one, but the Extensor digitorum unos

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112 Not the supinator but the.

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114 Intrinsic Muscles of the Hand

115 Intrinsic Muscles of the Hand These small muscles: Lie in the palm of the hand (none on the dorsal side) Move the metacarpals and fingers Control precise movements (e.g., threading a needle) Are the main abductors and adductors of the fingers Produce opposition move the thumb toward the little finger

116 Intrinsic Muscles of the Hand Tendons of: Flexor digitorum profundus Flexor digitorum superficialis Third lumbrical Fourth lumbrical Opponens digiti minimi Flexor digiti minimi brevis Abductor digiti minimi Fibrous sheath Second lumbrical Dorsal interossei First lumbrical Adductor pollicis Flexor pollicis brevis Abductor pollicis brevis Opponens pollicis Flexor retinaculum Pisiform bone Flexor carpi ulnaris tendon Flexor digitorum superficialis tendons (a) First superficial layer Abductor pollicis longus Tendons of: Palmaris longus Flexor carpi radialis Flexor pollicis longus

117 Intrinsic Muscles of the Hand Flexor digitorum profundus tendon Flexor digitorum superficialis tendon Palmar interossei Opponens digiti minimi Flexor digiti minimi brevis (cut) Abductor digiti minimi (cut) (b) Second layer Flexor pollicis brevis Opponens pollicis Dorsal interossei Adductor pollicis Abductor pollicis brevis Flexor pollicis longus tendon

118 But. Tendons of: Flexor digitorum profundus Flexor digitorum superficialis Third lumbrical Fourth lumbrical Opponens digiti minimi Flexor digiti minimi brevis Abductor digiti minimi Pisiform bone Flexor carpi ulnaris tendon Flexor digitorum superficialis tendons (a) First superficial layer Fibrous sheath Second lumbrical Dorsal interossei First lumbrical Adductor pollicis Flexor pollicis brevis Abductor pollicis brevis Opponens pollicis Flexor retinaculum Abductor pollicis longus Tendons of: Palmaris longus Flexor carpi radialis Flexor pollicis longus

119 And Flexor digitorum profundus tendon Flexor digitorum superficialis tendon Palmar interossei Opponens digiti minimi Flexor digiti minimi brevis (cut) Abductor digiti minimi (cut) (b) Second layer Flexor pollicis brevis Opponens pollicis Dorsal interossei Adductor pollicis Abductor pollicis brevis Flexor pollicis longus tendon

120 Except for these.know these, for this class, can t guarantee you won t need to know the others later in life Opponens digiti minimi Flexor digiti minimi brevis Abductor digiti minimi Flexor pollicis brevis Abductor pollicis brevis Opponens pollicis

121 Intrinsic Muscles of the Hand: Groups There are three groups of intrinsic hand muscles Thenar eminence (ball of the thumb) and Hypothenar eminence (ball of the little finger) each have a flexor, an abductor, and an opponens muscle Midpalm muscles, the lumbricals and interossei, extend the fingers The interossei also abduct and adduct the fingers

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124 Lower Extremity

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127 Eadweard Muybridge Born Died Resting place Occupation Edward James Muggeridge April 9, 1830( ) Kingston upon Thames, England May 8, 1904 (aged 74) Kingston upon Thames Woking Photographer

128 Muscles Crossing Hip and Knee Joints Most anterior compartment muscles of the hip and thigh flex the femur at the hip and extend the leg at the knee Posterior compartment muscles of the hip and thigh extend the thigh and flex the leg The medial compartment muscles all adduct the thigh These three groups are enclosed by the fascia lata

129 Fascia Lata (latae) not fascia latte

130 Movements of the Thigh at the Hip: Flexion The most important thigh flexors are the iliopsoas (prime mover), tensor fasciae lata, and rectus femoris

131 Movements of the Thigh at the Hip: Flexion Iliac crest Psoas major Iliopsoas Iliacus Anterior superior iliac spine Tensor fasciae latae Rectus femoris

132 Movements of the Thigh at the Hip: Flexion

133 Movements of the Thigh at the Hip: Flexion The medially located adductor muscles and sartorius assist in thigh flexion If they assist that would make them?????? A) agonists B) synergists C) fixators D) protagonists E) assistorius

134 Movements of the Thigh at the Hip: Flexion Iliopsoas Psoas major Iliacus Anterior superior iliac spine Tensor fasciae latae Pectineus Sartorius Adductor longus Rectus femoris Adductor magnus

135 Movements of the Thigh at the Hip: Flexion Adductor brevis Adductor longus Adductor magnus Femur

136 Movements of the Thigh at the Hip: Flexion

137 Movements of the Thigh at the Hip: Extension Thigh extension is primarily effected by the hamstring muscles (biceps femoris, semitendinosus, and semimembranosus) Forceful extension is aided by the gluteus maximus

138 Movements of the Thigh at the Hip: Extension Gluteus maximus Long head Short head Biceps femoris Semitendinosus Semimembranosus Hamstrings

139 Movements of the Thigh at the Hip: Extension

140 Movements of the Thigh at the Hip: Extension

141 Movements of the Thigh at the Hip: Medial Rotation ABduction and medial rotation are effected by the gluteus medius and gluteus minimus, and are antagonized by the lateral rotators

142 Movements of the Thigh at the Hip: Medial Rotation Gluteus medius (cut) Gluteus minimus

143 Movements of the Thigh at the Hip: Medial Rotation

144 Movements of the Thigh at the Hip: Lateral Rotation

145 Movements of the Thigh at the Hip: Lateral Rotation Superior gemellus Obturator internus Inferior gemellus Piriformis Obturator externus Quadratus femoris

146 Movements of the Thigh at the Hip: Lateral Rotation

147 Movements of the Thigh at the Hip: Adduction Thigh adduction is the role of five adductor muscles (adductor magnus, adductor longus, adductor brevis, pectineus, and gracilis)

148 Movements of the Thigh at the Hip: Adduction Pectineus (cut) Adductor longus Adductor magnus Femur

149 Movements of the Thigh at the Hip: Flexion

150 Movements of the Knee Joint

151 Movements of the Knee Joint The sole extensor of the knee is the quadriceps femoris The hamstring muscles flex the knee, and are antagonists to the quadriceps femoris Vastus lateralis Vastus intermedius Vastus medialis Rectus femoris tendon (cut) Patella Patellar ligament

152 Movements of the Knee Joint

153 Muscles of the Leg: Movements Various leg muscles produce the following movements at the: Ankle dorsiflexion and plantar flexion Intertarsal joints inversion and eversion of the foot Toes flexion and extension

154 Muscles of the Anterior Compartment These muscles are the primary toe extensors and ankle dorsiflexors They include the tibialis anterior, extensor digitorum longus, extensor hallucis longus, and fibularis tertius Tibia Tibialis anterior Extensor digitorum longus Extensor hallucis longus Superior and inferior extensor retinacula

155 Muscles of the Anterior Compartment Tibialis anterior Extensor hallucis longus Extensor digitorum longus

156 Muscles of the Anterior Compartment

157 Muscles of the Lateral Compartment These muscles plantar flex and evert the foot They include the fibularis longus and fibularis brevis muscles Fibularis brevis Fibularis longus

158 Muscles of the Lateral Compartment Fibularis longus Fibularis brevis Tendon of fibularis longus

159 Muscles of the Lateral Compartment

160 Muscles of the Posterior Compartment These muscles primarily flex the foot and the toes They include the gastrocnemius, soleus, tibialis posterior, flexor digitorum longus, and flexor hallucis longus Gastrocnemius Medial head Lateral head Tendon of gastrocnemius Calcaneal tendon Medial malleolus

161 Muscles of the Posterior Compartment Soleus Tendon of plantaris Tibialis posterior Fibula Flexor digitorum longus Flexor hallucis longus

162 Muscles of the Posterior Compartment

163 I know that you know that there is no need to know and no time to know everything there is to know, so, no need to know the intrinsic foot muscles. Muscles, end