What are the muscles of the scapulothoracic joint?
The scapulothoracic “joint” is made up of the scapula (shoulder blade) and its articulation with the ribcage. In between these structures are 2 muscles, namely the subscapularis (aka one of the rotator cuff muscles) and the serratus anterior.
What are the 6 muscles used in scapular stabilization?
Scapulothoracic joint stability Such muscles to consider are the serratus anterior, serratus posterior, the trapezius (upper / middle / lower), the rhomboids, teres major, the levator scapulae, the latissimus dorsi and the flexibility and mobility of the thoracolumbar fascia.
What is the Scapulothoracic?
The scapulothoracic motion interface is the site of movement between the scapula (shoulder blade) and the thorax (chest wall). The scapula moves around the chest in many daily and athletic activities. This motion does not take place between layers of muscles which separate the scapula from the ribs.
What are the 4 main RoM's that can occur at the scapular joint?
Elevation (range of motion 40°) - depression (RoM 10°) Protraction (20°) - retraction (15°) External rotation (60°) - Internal rotation (30°)
How many muscles connect to the scapula?
It connects with the humerus at the glenohumeral joint as well as the clavicle at the acromioclavicular joint to form the shoulder joint. In total, 17 different muscles attach to the scapula, which makes it difficult to fracture.
What muscle pulls scapula down?
The rhomboids are rhombus-shaped and are used to pull the shoulder blades together. They also rotate the scapula in a downward direction and provide stability for your shoulders.
Why is the Scapulothoracic a false joint?
The Scapulothoracic (ST) “joint” is not a true anatomic joint as it has none of the usual joint characteristics (union by fibrous, cartilaginous, or synovial tissues).
What muscles do scapular upward rotation?
Upward rotation is accomplished by the trapezius and serratus anterior muscles.
What muscle is trap?
The trapezius is a muscle that starts at the base of your neck, goes across your shoulders and extends to the middle of your back. The trapezius (traps muscle) helps you move your head, neck, arms, shoulders and torso. It also stabilizes your spine and helps with posture.
How many muscles anchor themselves to the scapulothoracic joint?
There are 17 muscles that attach to or originate on the scapula (see Table 1 below), and they perform two major roles: (1) to maintain a stable base of support for the humerus and (2) to allow for dynamic positioning of the glenoid fossa during glenohumeral elevation.
What muscles protract the scapula?
Serratus anterior muscle – its insertion is along the medial border, from the superior angle to the inferior angle. This muscle protracts and rotates the scapula. It is innervated by the long thoracic nerve.
Which muscle will depress the scapula or elevate the ribs?
Pectoralis minor draws the scapula forward and downward, and raises the ribs in forced inspiration. The subclavius muscle is a small muscle that lies deep to pectoralis major muscle.
What muscles stabilize the shoulder?
The primary muscle group that supports the shoulder joint is the rotator cuff muscles. The four rotator cuff muscles are the supraspinatus, infraspinatus, teres minor, and subscapularis.
Which muscles move and stabilize the shoulder blades?
The third group of muscles includes the levator scapulae, trapezius, rhomboids, and serratus anterior. These muscles are responsible for rotational movements and stabilization of the scapula.
What stabilizer muscles are strengthened during cervical scapular stabilization exercises?
The serratus anterior, rhomboid major and minor, levator scapulae, and trapezius muscles are the main muscles that stabilize the scapula [24].
What is SCAP stability?
What are the Scapula Stabilisers? Your shoulder blades (scapula) are attached to your ribcage by several muscles. These muscles all pull in different directions to help keep your shoulder blades stable while your arms move and take load, these are known as your scapula stabilisers.
What is the primary motion of the scapula during active elevation of the arm?
Retraction of the scapula is often performed in the context of pulling an object towards the body. Upward rotation of the scapula on the thorax is the primary motion of the scapula observed during active elevation of the arm and plays a significant role in increasing the range of elevation of the arm overhead.
What is the magnitude of upward rotation at rest?
If the vertebral or medial border of the scapula is used as the reference axis, the magnitude of upward rotation at rest is usually described as 2° to 3° from vertical. Although these “normal” values for the resting scapula are cited, substantial individual variability exists in scapular rest position, even among healthy subjects.
How many rotations of the scapula are there?
The motions of the scapula from the resting or reference position includes three rotations that occur at the AC joint. These are:
What is SC protraction?
SC protraction increases the extent of forward reach. As SC protraction occurs as a summation of both SC and AC joint, a decrease in motion at one joint can be atleast partially compensated by an increase at the other.
Where is the scapula located?
Normally, the scapula rests at a position on the posterior thorax approximately 2 inches from the midline, between the second through seventh ribs (scapula extends from the level of T2 spinous process to T7 orT9 spinous process, depending on the size of the scapula) and the medial border is about 6 cms lateral to the spine.
What is the movement of the scapulothoracic joint?
Movements of scapulothoracic joint are a very important element of shoulder kinesiology. The wide range of motion available to the shoulder joint is due to the large movement available at ST joint.
Does the scapula have translatory motions?
The scapula also has available translatory motions of scapular elevation/depression and protraction/retraction. The linkage of the scapula to the AC and SC joints prevents scapular motions both from occurring in isolation and from occurring as true translatory motions. Instead, scapular motions on the thorax must occur in combinations, such as the simultaneous upward rotation, external rotation, and posterior tipping that occur when the arm is abducted.
What muscles connect the scapula to the arm?
Scapula-to-arm muscles include the four muscles of the rotator cuff, the biceps, the triceps, the coracobrachialis, the deltoid and part of the latissimus dorsi. Scapula-to-torso muscles include the rhomboids, the serratus anterior, and the trapezius. The serratus anterior muscle originates from the ribs and inserts on the medial scapular border; the trapezius originates from the vertebrae and inserts along the scapular spine. Dysfunction of the scapula-to-torso muscles can produce abnormal scapulothoracic motion and thereby disrupt normal glenohumeral joint mechanics. This scapular abnormality can thus be the cause of shoulder pain.
Why does my scapular flip?
Lateral scapular winging is caused by dysfunction of the trapezius or the spinal accessory nerve that supplies it . In that setting, the serratus anterior works unopposed. This is usually an iatrogenic injury during neck surgery. The scapular flip sign can detect a spinal accessory nerve palsy.
What is the treatment for scapulothoracic dyskinesis?
The mainstay of scapulothoracic dyskinesis is physical therapy , though if this condition is caused by a primary abnormality elsewhere, such as a clavicular or AC joint abnormality, physical therapy is unlikely to produce more than frustration. The underlying abnormality must be addressed.
What is the SICK scapula?
Scapulothoracic dyskinesis can be thought of as “SICK” scapula, which can remind the examiner of three associated findings: S capular malposition, I nferior medial border prominence, C oracoid pain and malposition, leading to dys K inesis of scapular movement.
Which bursae facilitate the gliding of the scapula on the chest wall?
The scapulothoracic bursae (plural) facilitate the gliding of the scapula on the chest wall.
What is scapular physical therapy?
For scapular conditions in general, physical therapy is focused on relative rest, increasing core muscle strength and balance, and improving posture.
Does scapulothoracic dyskinesis respond to rest?
Scapulothoracic dyskinesis due to overuse also responds well to rest and rehabilitation . The outcomes in patients with scapulothoracic dyskinesis due to underlying abnormalities are governed by the response to treatment of those conditions.
Which joint is directly involved with the postural distortion pattern known as rounded shoulders?
The scapulocostal joint is directly involved with the postural distortion pattern known as rounded shoulders, which is part of a larger postural distortion pattern known as upper crossed syndrome.
Is the scapulocostal joint osseous?
The scapulocostal joint is not a typical osseous anatomic joint. It is NOT two bones connected directly to each other by fibrous or cartilaginous tissue, or by a bilayer synovial capsule. In other words, it is NOT a fibrous joint, nor a cartilaginous joint, nor a synovial joint. Rather, the scapula and thoracic rib cage wall are united via multiple muscle attachments.
Is a joint a functional interface?
For this reason, anatomists often state that it is NOT a joint, rather it is a functional interface . However, a physiologist would say that the primary function of a joint is to have movement of one bone or body part relative to another, therefore it IS a joint.
What is the scapula?
The scapula, commonly referred to as the “shoulder blade,” is a large, flat bone that sits on top of the rib cage and is held in place by the many muscles of the shoulder girdle. Unlike most other joints in the body, the scapulothoracic joint does not connect to the body by fibrous (eg: the skull), cartilaginous (eg: intervertebral discs), or synovial (eg: the hip) tissues. The scapulothoracic joint relies on the coordinated dance of 17 muscles (*see bottom of post for the complete list of muscles that attach to the scapula), as well as its mobility at three other joints — the acromioclavicular, sternoclavicular, and glenohumeral joints — to provide stability for the rest of the arm and shoulder.
How to get rid of a swollen chest?
Stand tall, bringing shoulders down and back and engage abdominal muscles (do not hunch shoulders or push out ribs). Draw elbows back while squeezing shoulder blades together behind you. You should feel the muscles between your shoulder blades activate and your chest opens up.
What muscle is used to prevent injury?
Whether you play a racquet sport or you are just trying to put your suitcase in an overhead compartment on an airplane, scapular muscle strength and mobility are key to preventing injury. Weakness in the shoulder “core” and not using the larger, stronger muscles closer to the body can lead to overuse of the smaller muscles in our extremities. Common overuse injuries include tennis elbow (lateral epicondylitis), golfer’s elbow (medial epicondylitis), tendinitis, DeQuervain’s tenosynovitis, and skier’s thumb.
How to do the T and I?
Dynamic T and I: Lay face down with arms out to sides like the letter “T.” While drawing the belly in and maintaining a neutral spine, lift arms up to sides while maintaining a “T” position by engaging muscles between shoulder blades. Gently lower arms until they are down by your side, creating the letter “ I.” Return to “T” and repeat this movement. Do not arch lower back or lift head up. (Perform 2 sets of 10.)
Which muscles are involved in the movement of the scapula?
Weakness in any one of the muscles attaching to the shoulder blade, particularly in the larger scapular muscles such as the serratus anterior, latissimus dorsi, rhomboids, and trapezius muscles, can affect the way the scapula moves and how the shoulder joint functions.
How to strengthen scapular stabilization?
Here are 5 exercises to improve scapular stabilization: Standing Rows: Stand facing the anchor with resistance band at elbow height. Step back until your arms are straight and the band has mild tension. Stand tall, bringing shoulders down and back and engage abdominal muscles (do not hunch shoulders or push out ribs).
How to do modified plank with protraction?
Modified Plank With Protraction: Begin in a modified plank position resting on forearms. While maintaining a neutral spine (draw the belly up towards spine for transverse abdominus muscle engagement), activate serratus anterior by pushing through forearms, allowing shoulder blades to separate farther apart.
