supraspinatus muscle

Information about supraspinatus muscle

Muscles on the dorsum of the scapula, and the Triceps brachii muscle: #3 is Latissimus dorsi muscle
#5 is Teres major muscle
#6 is Teres minor muscle
#7 is Supraspinatus muscle
#8 is Infraspinatus muscle
#13 is long head of Triceps brachii muscle
Posterior view of muscles connecting the upper extremity to the vertebral column. Supraspinatus muscle is labeled in red at right, while it is covered by other muscles at left. Origin = supraspinous fossa of scapula
Latinmusculus supraspinatus
subject #123 440
Origin:
Insertion:superior facet of greater tubercle of humerus
Artery:suprascapular artery
Nerve:suprascapular nerve
Action:abduction of arm and stabilizes humerus
Dorlands/Elsevier m_22/12551039
The supraspinatus is a relatively small muscle of the upper limb that takes its name from its origin from the supraspinous fossa superior to the spine of the scapula. It is one of the four rotator cuff muscles and also abducts the arm at the shoulder. The spine of the scapula separates the supraspinatus muscle from the infraspinatus muscle, which originates below the spine.

Origin

The supraspinatus muscle arises from the supraspinous fossa, a shallow depression in the body of the scapula above its spine. The supraspinatus muscle tendon passes laterally beneath the cover of the acromion.

Insertion

The supraspinatus tendon is inserted into the most superior facet of the greater tubercle of the humerus.

The distal attachments of the three rotator cuff muscles that insert into the greater tubercle of the humerus can be abbreviated as SIT when viewed from superior to inferior (Supraspinatus, Infraspinatus, and Teres minor).

The much fabled mnemonic SITS regarding the rotator cuff muscles is completed by including the Subscapularis muscle, which unlike the other rotator cuff muscles attaches to the lesser tubercle of the humerus.[1]

Innervation

The supraspinatus muscle is supplied by the suprascapular nerve (C5 and C6), which arises from the superior trunk of the brachial plexus and passes laterally through the posterior triangle of the neck and through the scapular notch on the superior border of the scapula. After supplying fibers to the supraspinatus muscle, it supplies articular branches to the capsule of the shoulder joint.

This nerve can be damaged along its course in fractures of the overlying clavicle, which can reduce the person’s ability to initiate the abduction.

Action

Contraction of the supraspinatus muscle leads to abduction of the arm at the shoulder joint. It is the main agonist muscle for this movement during the first 15 degrees of its arc. Beyond 15 degrees the deltoid muscle becomes increasingly more effective at abducting the arm and becomes the main propagator of this action.

The supraspinatus muscle is one of the musculotendinous support structures called the rotator cuff that surround and enclose the shoulder. It helps to resist the inferior gravitational forces placed across the shoulder joint due to the downward pull from the weight of the upper limb.

The supraspinatus also helps to stabilize the shoulder joint by keeping the head of the humerus firmly pressed medially against the glenoid fossa of the scapula.

Clinicial significance

The supraspinatus muscle tendon is often ruptured in sports involving sudden forceful movements of the upper limb and is the most commonly ruptured rotator cuff muscle. The muscle can also degenerate in the elderly leading to increased instability and loss of function at the shoulder joint.

The supraspinatus tendon can also become inflamed, in persons of any age, leading to a condition called Supraspinatus tendinitis. In this condition initiation of abduction of the shoulder is difficult or impossible, but all other movements are full and pain free. If the therapist support the initial abduction [that is about 15 degree] the further movment is done by the patient himself. The definitive cause of this condition is not clear, although it suspected, without definite evidence, to be an after-effect of minor trauma to the shoulder joint. Treatment may be by anti-inflammatory medication or by simple analgesics, but steroid injection directly into the tendon provides the best chance of early resolution.

Additional images


Diagram of the human shoulder joint

Left scapula. Dorsal surface.

Left humerus. Anterior view.

The scapular and circumflex arteries.

The right brachial plexus with its short branches, viewed from in front.

Suprascapular and axillary nerves of right side, seen from behind.

The suprascapular, axillary, and radial nerves.


References

External links

 •  • [ e]
Muscles of upper limbs
VERTEBRAL COLUMNtrapezius - latissimus dorsi - rhomboid major - rhomboid minor - levator scapulae
THORACIC WALLSpectoralis major - pectoralis minor - subclavius - serratus anterior
SHOULDERdeltoid - rotator cuff (supraspinatus, infraspinatus, teres minor, subscapularis) - teres major
ARManterior compartment: coracobrachialis - biceps brachii - brachialis
posterior compartment: triceps brachii - anconeus
FOREARManterior compartment: super. - pronator teres - palmaris longus - flexor carpi radialis - flexor carpi ulnaris - flexor digitorum superficialis - deep - pronator quadratus - flexor digitorum profundus - flexor pollicis longus
posterior compartment: super. - mobile wad (brachioradialis, extensor carpi radialis longus and brevis) - extensor digitorum, - extensor digiti minimi - extensor carpi ulnaris - deep - supinator - anatomical snuff box (abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus) - extensor indicis
HANDlateral volar - thenar (opponens pollicis, flexor pollicis brevis, abductor pollicis brevis, adductor pollicis)
medial volar - palmaris brevis - hypothenar (abductor minimi digiti, flexor digiti minimi brevis, opponens digiti minimi)
intermediate - lumbrical - dorsal interossei - palmar interossei
scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone).

The scapula forms the posterior part of the shoulder girdle. In humans, it is a flat bone, roughly triangular in shape.
..... Click the link for more information.
The triceps brachii muscle is often simply called the triceps (both singular and plural). However, the term triceps (Latin for "three-headed") can mean any skeletal muscle having three origins.
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The latissimus dorsi (plural: latissimi dorsi) is the large, flat, dorso-lateral muscle on the trunk, posterior to the arm, and partly covered by the spinotrapezius on its median dorsal region.
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Teres major is a muscle of the upper limb and one of six scapulohumeral muscles. It is a thick but somewhat flattened muscle.

Origin and insertion

It arises from the oval area on the dorsal surface of the inferior angle of the scapula, and from the fibrous septa
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The Teres minor is a narrow, elongated muscle of the rotator cuff.

Origin and insertion

It arises from the dorsal surface of the axillary border of the scapula for the upper two-thirds of its extent, and from two aponeurotic laminæ, one of which separates it from the
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The Infraspinatus muscle is a thick triangular muscle, which occupies the chief part of the infraspinatous fossa.

Origin and insertion

It attaches medially to the infraspinous fossa of the scapula and laterally to the greater tubercle of the humerus.
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The triceps brachii muscle is often simply called the triceps (both singular and plural). However, the term triceps (Latin for "three-headed") can mean any skeletal muscle having three origins.
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The supraspinatous fossa (supraspinatus fossa, supraspinous fossa) of the scapula, smaller than the infraspinatous fossa, is concave, smooth, and broader at its vertebral than at its humeral end; its medial two-thirds give origin to the Supraspinatus.
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scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone).

The scapula forms the posterior part of the shoulder girdle. In humans, it is a flat bone, roughly triangular in shape.
..... Click the link for more information.
Latin}}} 
Official status
Official language of: Vatican City
Used for official purposes, but not spoken in everyday speech
Regulated by: Opus Fundatum Latinitas
Roman Catholic Church
Language codes
ISO 639-1: la
ISO 639-2: lat
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bold refer to the diagram at right.)

In the skull (8):
  • 1-9. cranium
  • 7. mandible
''In the middle ears (6):
  • malleus
  • incus
  • stapes
In the throat (1):
  • hyoid
In the shoulder girdle (4):
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bold refer to the diagram at right.)

In the skull (8):
  • 1-9. cranium
  • 7. mandible
''In the middle ears (6):
  • malleus
  • incus
  • stapes
In the throat (1):
  • hyoid
In the shoulder girdle (4):
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The greater tubercle of the humerus is situated lateral to the head and lesser tubercle.

Its upper surface is rounded and marked by three flat impressions.
  • the highest of these gives ("superior facet") insertion to the Supraspinatus

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The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. On a skeleton, it fits between the scapula and the ulna. It consists of the following three sections:
  • Upper extremity of humerus
  • Body of humerus

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Arteries are muscular blood vessels that carry blood away from the heart.[1] All arteries, with the exception of the pulmonary and umbilical arteries, carry oxygenated blood.

The circulatory system is extremely important for sustaining life.
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The suprascapular artery (or transverse scapular artery) is a branch of the thyrocervical trunk. At first, it passes downward and laterally across the scalenus anterior and phrenic nerve, being covered by the sternocleidomastoid muscle; it then crosses the subclavian artery
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  • Accessory nerve
  • Accessory obturator nerve
  • Alderman's nerve
  • Anococcygeal nerve
  • Ansa cervicalis
  • Anterior interosseous nerve
  • Anterior superior alveolar nerve
  • Aortic plexus
  • Auerbach's plexus
  • Auriculotemporal nerve
  • Axillary nerve

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The suprascapular nerve arises from the trunk formed by the union of the fifth and sixth cervical nerves. It innervates the supraspinatus muscles and infraspinatus muscles.
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Kinesiology is the scientific study of the anatomy, physiology, and mechanics of body movement, especially in humans. [1] The word kinesiology is derived the Greek "kinesis" (motion) + the suffix -ology or -logy from the greek "logos" or "logia"(meaning a field of study).
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Abduction, in functional anatomy, is a movement which draws a limb away from the median (Sagittal) plane of the body. It is thus opposed to adduction.

Muscles of abduction

Upper limb

the coming together of two bones attached by a joint laterally

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The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. On a skeleton, it fits between the scapula and the ulna. It consists of the following three sections:
  • Upper extremity of humerus
  • Body of humerus

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Elsevier, the world's largest publisher of medical and scientific literature, forms part of the Reed Elsevier group. Based in Amsterdam, the company has substantial operations in the UK, USA and elsewhere.
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The supraspinatous fossa (supraspinatus fossa, supraspinous fossa) of the scapula, smaller than the infraspinatous fossa, is concave, smooth, and broader at its vertebral than at its humeral end; its medial two-thirds give origin to the Supraspinatus.
..... Click the link for more information.
scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone).

The scapula forms the posterior part of the shoulder girdle. In humans, it is a flat bone, roughly triangular in shape.
..... Click the link for more information.
The rotator cuff (rotor cuff) is an anatomical term given to the group of muscles and their tendons that act to stabilize the shoulder. Along with the teres major and the deltoid the four muscles of the rotator cuff make up the six scapulohumeral
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The Infraspinatus muscle is a thick triangular muscle, which occupies the chief part of the infraspinatous fossa.

Origin and insertion

It attaches medially to the infraspinous fossa of the scapula and laterally to the greater tubercle of the humerus.
..... Click the link for more information.
The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. On a skeleton, it fits between the scapula and the ulna. It consists of the following three sections:
  • Upper extremity of humerus
  • Body of humerus

..... Click the link for more information.
The lesser tubercle of the humerus, although smaller, is more prominent than the greater tubercle: it is situated in front, and is directed medialward and forward.

Above and in front it presents an impression for the insertion of the tendon of the Subscapularis.
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The suprascapular nerve arises from the trunk formed by the union of the fifth and sixth cervical nerves. It innervates the supraspinatus muscles and infraspinatus muscles.
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In human anatomy, the deltoid muscle is the muscle forming the rounded contour of the shoulder.

It was previously called the Deltoideus and the name is still used by some anatomists. It is called so because it is in the shape of the Greek letter Delta (triangle).
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