Key facts about the subscapularis muscleTable quiz
| Origin | Subscapular fossa of scapula |
| Insertion | Lesser tubercle of humerus |
| Action | Shoulder joint: Arm internal rotation St ... |
| Innervation | Upper and lower subscapular nerves (C5 - ... |
| Blood supply | Suprascapular artery, axillary artery, s ... |
What muscles does the hypoglossal nerve innervate?
- Muscles of mastication which include Mandibular elevators masseter muscle temporalis muscle medial pterygoid muscle Mandibular depressors lateral pterygoid muscle anterior belly of the diagstric muscle mylohyoid muscle
- Tensor palati
- Tesnor tympani
What muscle is innervated by the trochlear nerve?
The trochlear nerve (/ˈtrɒklɪər/), also called the fourth cranial nerve or CN IV, is a motor nerve (a somatic efferent nerve) that innervates just one muscle: the superior oblique muscle of the eye, which operates through the pulley-like trochlea.
What innervates the vagus nerve?
Vagus nerve
- Cranial nerves. The cranial nerves are 12 pairs of nerves that emerge from the brain, with a majority of the nerves originating in the brainstem.
- Origin. Synonyms: Nucleus of the solitary tract, Nucleus solitarius , show more ...
- Branches of the vagus nerve. ...
- Development. ...
Which nerve innervates the supinator?
Supinator muscle
- Origin and insertion. The wide supinator muscle consists of superficial and deep layers. ...
- Relations. Supinator is found deep in the forearm, superficial only to the parts of the radius and ulna over which the muscle lies.
- Innervation. Supinator is innervated by the posterior interosseous nerve (C7, C8), a branch of the radial nerve. ...
- Blood supply
- Function. ...
What muscles are innervate by the lower subscapular nerve?
The lower subscapular nerve innervates the subscapularis muscle and the teres major muscle. These muscles medially rotate and adduct the humerus.
What does the upper and lower subscapular nerve innervate?
The upper and lower subscapular nerves come from the posterior cord. The lower subscapular nerve (C5-C6) innervates teres major; and both the upper and lower subscapular nerves innervate the subscapularis, the third muscle of the rotator cuff apparatus.
Is the lower subscapular nerve motor or sensory?
It receives nerve fibers that originate in the nerve roots C5 and C6 (and sometimes C4). The suprascapular nerve is a mixed nerve, meaning that it provides both sensory and motor supply for the suprascapular region....Suprascapular nerve.OriginSuperior trunk of brachial plexusBranchesMotor muscular branches, sensory articular branches1 more row•Nov 24, 2021
What does upper Subscapular innervate?
The upper subscapular nerve contains axons from the ventral rami of the C5 and C6 cervical spinal nerves. It innervates the superior portion of the subscapularis muscle. The inferior portion of the subscapularis is innervated by the lower subscapular nerve.
What muscles do suprascapular nerve innervate?
The suprascapular nerve has a motor and sensory innervation. Its motor innervation is to the supraspinatus and infraspinatus muscles. The supraspinatus and infraspinatus muscles are two of the four muscles that make up the glenohumeral (shoulder) joint.
What function does the subscapularis?
Primary function is internal rotation of the humerus. It helps in shoulder adduction and extension in certain positions.
What does dorsal scapular nerve innervate?
The DSN is a motor nerve that innervates the levator scapulae, rhomboid major, and rhomboid minor muscles. These muscles work dynamically and collectively are considered periscapular stabilizing muscles.
What is suprascapular nerve entrapment?
Suprascapular nerve entrapment syndrome (SNES) is an often-overlooked etiology of shoulder pain and weakness. Treatment varies depending on the location and etiology of entrapment, which can be described as compressive or traction lesions. In some cases, treating the primary cause of impingement (ie.
What does the supraclavicular nerve innervate?
The supraclavicular nerves are three cutaneous nerves that emerge as a common trunk from the cervical plexus before branching to innervate the skin over the upper chest and shoulders.
What does the dorsal scapular nerve innervate?
The DSN is a motor nerve that innervates the levator scapulae, rhomboid major, and rhomboid minor muscles. These muscles work dynamically and collectively are considered periscapular stabilizing muscles.
What does medial brachial cutaneous nerve innervate?
[1] Specifically, the medial antebrachial cutaneous nerve provides sensory innervation of the medial forearm as well as the skin overlying the olecranon.
What does the subclavian nerve supply?
The subclavian nerve, also known as the nerve to subclavius, is an anterior branch from the C5 and C6 roots of the brachial plexus, and supplies the subclavius muscle.
What does the axillary nerve Innervates?
The axillary nerve has both a motor and a sensory distribution of innervation. It has motor fibres that innervate the deltoid muscle, acting as an abductor, flexor and extensor at the shoulder joint, as well as the teres minor muscle, allowing lateral rotation of the glenohumeral joint.
What nerve innervates the subscapularis muscle?
Lower subscapular nerve. The lower subscapular nerve, also known as the inferior subscapular nerve, is the third branch of the posterior cord of the brachial plexus. It innervates the inferior portion of the subscapularis muscle and the teres major muscle .
What is the inferior subscapular nerve?
Latin. Nervus subscapularis inferior. TA2. 6429. FMA. 65307. Anatomical terms of neuroanatomy. The lower subscapular nerve, also known as the inferior subscapular nerve, is the third branch of the posterior cord of the brachial plexus. It innervates the inferior portion of the subscapularis muscle and the teres major muscle .
Which nerve innervates the subscapularis muscle and the teres major muscle?
The lower subscapular nerve innervates the subscapularis muscle and the teres major muscle. These muscles medially rotate and adduct the humerus.
Which nerve is the third branch of the posterior cord of the brachial plexus?
Structure. The lower subscapular nerve contains axons from the ventral rami of the C5 and C6 cervical spinal nerves. It is the third branch of the posterior cord of the brachial plexus. It gives branches to 2 muscles: subscapularis muscle.
Which nerves innervate the subscapular nerve?
Subscapularis is innervated by the upper and lower subscapular nerves (C5-C6), that stem from the superior and posterior cords of the brachial plexus, respectively.
Where is the subscapularis muscle located?
Reading time: 6 minutes. Subscapularis muscle (Musculus subscapularis) Subscapularis is a triangular shoulder muscle located in the subscapular fossa of scapula. Attaching between the scapula and the proximal humerus, it is one of the four muscles of the rotator cuff, along with supraspinatus, ...
What is the role of subscapularis in shoulder joint?
Subscapularis is an important stabilizer of the shoulder joint when the deltoid, pectoralis major, biceps and triceps brachii muscles are active. These muscles are responsible for several over-head movements of the arm (e.g. throwing, pulling downwards), during which the force of subscapularis prevents upward shoulder dislocation. However during these particular movements, subscapularis is also the most prone to impingement.
What is the lower triangular space?
Lower triangular space (triangular interval), here the subscapularis makes up the anterior border . Teres major, long head of triceps brachii and the humerus comprise the posterior, medial and lateral borders of this space, respectively. This space serves as a passageway for the radial nerve and deep brachial artery.
What is the posterior surface of the muscle?
The posterior surface of the muscle’s tendon is blended with the fibrous capsule of the glenohumeral joint, and is continuous with the tendons of supraspinatus, infraspinatus, teres minor and long head of triceps brachii. These tendons together comprise the rotator capsule around the shoulder joint.
Which muscle is the only medial rotator cuff?
Function. The subscapularis muscle is the only medial (internal) rotator of all the rotator cuff muscles. Due to its unique axis of pull, from the proximal humerus to the costal scapular surface, subscapularis medially rotates ( internal rotation) the humeral head within the glenoid fossa.
Where does the subscapular bursa connect to the shoulder?
The large subscapular bursa that communicates with the shoulder joint separates the subscapularis tendon from the neck of the scapula. The tendon then inserts to the lesser tubercle of humerus and anterior part of the articular capsule of the glenohumeral joint.
What is the function of the suprascapular nerve?
The main function of this nerve is to provide motor innervation for two muscles, which are the supraspinatus and infraspinatus muscles . These muscles are part of the muscle group called the rotator cuff muscles . In addition, the suprascapular nerve provides a sensory supply for the joints of the scapula ( glenohumeral and acromioclavicular joints ).
Where does the suprascapular nerve originate?
The suprascapular nerve (root value C5, C6) originates from the superior trunk of the brachial plexus. It is considered to be one of the preterminal branches or supraclavicular branches of the brachial plexus together with the dorsal scapular nerve , long thoracic nerve , subclavian nerve and accessory phrenic nerve. Note that the cords of the brachial plexus are called the infraclavicular branches of the brachial plexus, while the nerves that branch off from the cords are the terminal branches of the brachial plexus.
What nerve is the lateral branch of the superior trunk of the brachial plexus?
The suprascapular nerve is the lateral branch of the superior trunk of the brachial plexus . It receives nerve fibers that originate in the nerve roots C5 and C6 (and sometimes C4). The suprascapular nerve is a mixed nerve, meaning that it provides both sensory and motor supply for the suprascapular region.
What is the cause of a weakened shoulder?
It is usually caused by a traumatic injury to the suprascapular nerve which causes the damage of its nerve fibers and consequential weakness of the supraspinatus and infraspinatus muscles. The other frequent cause is traumatic or non-traumatic compression of the nerve on its path through the suprascapular notch.
Where is the suprascapular nerve located?
The suprascapular nerve is a peripheral nerve of the shoulder and arm. It arises from the upper portion of the brachial plexus, which is a network of nerves that stretches across your check from your neck down to your armpit. The suprascapular nerve’s roots emerge from the fifth and sixth cervical vertebrae (C5 and C6) in your neck.
What causes the suprascapular nerve to lose sensation?
Nerve damage can be caused by trauma, disease, or physical abnormalities.
How many branches does the suprascapular nerve have?
The suprascapular nerve has four main branches, two motor and two sensory.
Where does the nerve pass through the scapula?
After it reaches the top of the scapula, the nerve passes under the transverse scapular ligament and through the suprascapular notch. It then enters the supraspinous fossa, which is a concave area on the scapula. There, the nerve sends branches inward (toward the spine) to the supraspinatus muscle, which sits high on the scapula.
What nerve root is C4?
Nerve fibers from C4 (the fourth cervical nerve root) in addition to the usual C5 and C6
Why is it important to know the anatomical variations of a nerve?
It’s important for doctors to know what anatomical variations are possible so they can diagnose and treat nerve problems in people who have these variations . Knowing any alternate nerve routes is especially crucial during surgery, so the surgeon can avoid accidentally damaging the nerve.
Which nerve supplies sensation to the skin?
Most sensory nerve supply sensation to skin. The suprascapular nerve is different in that its sensory fibers, except in rare cases, only innervate joints.
