Winged scapula
Encyclopedia
A winged scapula is a condition in which the shoulder blade, or shoulder bone, protrudes from a person’s back in an abnormal position. It is a rare condition with the potential to lead to limited functional activity in the upper extremity with which it is adjacent
. It can affect a person’s ability to lift, pull, and push weighty objects. In some serious cases, the ability to perform activities of daily living
such as changing one’s clothes and washing one’s hair may be hindered. The name of this condition comes from its appearance, a wing-like resemblance, due to the medial border of the scapula sticking straight out from the back. Scapular winging has been observed to disrupt scapulohumeral rhythm, contributing to decreased flexion
and abduction
of the upper extremity, as well as a loss in power and the source of considerable pain. A winged scapula is considered normal posture in young children, but not older children and adults.
In most cases of winged scapula, damage to the serratus anterior causes the deformation of the back. The serratus anterior muscle attaches to the medial anterior aspect of the scapula
(i.e. it attaches on the side closest to the spine and runs along the side of the scapula that faces the rib
cage) and normally anchor the scapula against the rib cage
. When the serratus anterior contracts, upward rotation, abduction, and weak elevation of the scapula occurs, allowing the arm to be raised above the head. The long thoracic nerve
innervates the serratus anterior; therefore, damage to or impingement of this nerve can result in weakening or paralysis
of the muscle. If this occurs, the scapula may slip away from the rib cage, giving it the wing-like appearance on the upper back. This characteristic may particularly be seen when the affected person pushes against resistance.
The person may also have limited ability to lift their arm above their head.
In facioscapulohumeral muscular dystrophy (FSH), the winged scapula is detected during contraction of the glenohumeral joint. In this movement, the glenohumeral joint atypically and concurrently abducts and the scapula internally rotates.
paralysis
. This is typically caused by damage (i.e. lesion
s) to the long thoracic nerve
. This nerve supplies the serratus anterior, which is located on the side of the thorax and acts to pull the scapula forward. Serratus anterior palsy is a dysfunction that is characteristic of traumatic
, non-traumatic, and idiopathic
injury to the long thoracic nerve.
There are numerous ways in which the long thoracic nerve can sustain trauma-induced injury. These include, but are not limited to, blunt trauma (e.g. blow to the neck or shoulder, sudden depression of the shoulder girdle, unusual twisting of the neck and shoulder), repetitive movements (as observed in athletic activities such as weight lifting or sports that involve throwing), and household activities (e.g. gardening, digging, car washing, prolonged abduction of the arms when sleeping, propping up the head to read, etc.). Sometimes, other structures in the body such as inflamed and enlarged subcorocoid or subscapular
bursa
press on the nerve. Clinical treatments may also cause injury to the long thoracic nerve (iatrogenesis
from forceful manipulation, mastectomies with axillary node dissection, surgical treatment of spontaneous pneumothorax
, post-general anesthesia for various clinical reasons, and electrical shock, amongst others).
Non-traumatic induced injury to the long thoracic nerve includes, but is not limited to, causes such as viral illness (e.g. influenza
, tonsillitis
-bronchitis
, polio
), allergic-drug reactions, drug overdose, toxic exposure (e.g. herbicides, tetanus
), C7 radiculopathy
, and coarctation of the aorta
.
Secondary to serratus anterior palsy, a winged scapula is also caused by trapezius and rhomboid
palsy involving the accessory nerve
and the dorsal scapular nerve
, respectively.
Though the most common causes of a winged scapula is due to serratus anterior palsy, and less commonly trapezius and rhomboid palsy, there are still other circumstances that present the ailment. These incidences include direct injuries to the scapulothoracic muscles (i.e. trapezius and rhomboid muscles), and structural abnormalities (e.g. rotator cuff
pathology, shoulder instability, etc.).
muscles but if the muscles do not contract clinically and symptoms continue to be severe for more than 3–6 months, surgery may be the next choice. Surgery by fixation of the scapula
to the rib cage
can be done for those with isolated scapular winging. Some options are neurolysis (chordotomy), intercostal nerve transfer, scapulothoracic fusion, arthrodesis
(scapulodesis), or scapulothoracis fixation without arthrodesis (scapulopexy).
. In yet another report (Remak), there were three diagnoses of serratus anterior paralysis throughout a series of 12,000 neurological examinations.
Adjacent
Adjacent is an adjective meaning contiguous, adjoining or abuttingIn geometry, adjacent is when sides meet to make an angle.In graph theory adjacent nodes in a graph are linked by an edge....
. It can affect a person’s ability to lift, pull, and push weighty objects. In some serious cases, the ability to perform activities of daily living
Activities of daily living
Activities of Daily Living is a term used in healthcare to refer to daily self-care activities within an individual's place of residence, in outdoor environments, or both...
such as changing one’s clothes and washing one’s hair may be hindered. The name of this condition comes from its appearance, a wing-like resemblance, due to the medial border of the scapula sticking straight out from the back. Scapular winging has been observed to disrupt scapulohumeral rhythm, contributing to decreased flexion
Flexion
In anatomy, flexion is a position that is made possible by the joint angle decreasing. The skeletal and muscular systems work together to move the joint into a "flexed" position. For example the elbow is flexed when the hand is brought closer to the shoulder...
and abduction
Abduction (kinesiology)
Abduction, in functional anatomy, is a movement which draws a limb away from the median plane of the body. It is thus opposed to adduction.-Upper limb:* of arm at shoulder ** Supraspinatus** Deltoid* of hand at wrist...
of the upper extremity, as well as a loss in power and the source of considerable pain. A winged scapula is considered normal posture in young children, but not older children and adults.
Signs and symptoms
The severity and appearance of the winged scapula varies by individuals as well as the muscles and/or nerves that were affected. Pain is not seen in every case. In a study of 13 individuals with facioscapulohumeral muscular dystrophy (FSH), none of the individuals complained of pain. Fatigue, however, was a common characteristic and all had noted that there were limitations in their activities of daily life.In most cases of winged scapula, damage to the serratus anterior causes the deformation of the back. The serratus anterior muscle attaches to the medial anterior aspect of the scapula
Scapula
In anatomy, the scapula , omo, or shoulder blade, is the bone that connects the humerus with the clavicle ....
(i.e. it attaches on the side closest to the spine and runs along the side of the scapula that faces the rib
Rib
In vertebrate anatomy, ribs are the long curved bones which form the rib cage. In most vertebrates, ribs surround the chest, enabling the lungs to expand and thus facilitate breathing by expanding the chest cavity. They serve to protect the lungs, heart, and other internal organs of the thorax...
cage) and normally anchor the scapula against the rib cage
Rib cage
The rib cage is an arrangement of bones in the thorax of animals. It is formed by the vertebral column, ribs and sternum and encloses the heart and lungs....
. When the serratus anterior contracts, upward rotation, abduction, and weak elevation of the scapula occurs, allowing the arm to be raised above the head. The long thoracic nerve
Long thoracic nerve
The long thoracic nerve supplies the Serratus anterior. This nerve characteristically arises by three roots from the fifth, sixth, and seventh cervical nerves but the root from C7 may be absent...
innervates the serratus anterior; therefore, damage to or impingement of this nerve can result in weakening or paralysis
Paralysis
Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed...
of the muscle. If this occurs, the scapula may slip away from the rib cage, giving it the wing-like appearance on the upper back. This characteristic may particularly be seen when the affected person pushes against resistance.
The person may also have limited ability to lift their arm above their head.
In facioscapulohumeral muscular dystrophy (FSH), the winged scapula is detected during contraction of the glenohumeral joint. In this movement, the glenohumeral joint atypically and concurrently abducts and the scapula internally rotates.
Causes
The most common cause of scapular winging is serratus anteriorSerratus anterior muscle
The serratus anterior is a muscle that originates on the surface of the upper eight or nine ribs at the side of the chest and inserts along the entire anterior length of the medial border of the scapula.-Origin:...
paralysis
Paralysis
Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed...
. This is typically caused by damage (i.e. lesion
Lesion
A lesion is any abnormality in the tissue of an organism , usually caused by disease or trauma. Lesion is derived from the Latin word laesio which means injury.- Types :...
s) to the long thoracic nerve
Long thoracic nerve
The long thoracic nerve supplies the Serratus anterior. This nerve characteristically arises by three roots from the fifth, sixth, and seventh cervical nerves but the root from C7 may be absent...
. This nerve supplies the serratus anterior, which is located on the side of the thorax and acts to pull the scapula forward. Serratus anterior palsy is a dysfunction that is characteristic of traumatic
Trauma (medicine)
Trauma refers to "a body wound or shock produced by sudden physical injury, as from violence or accident." It can also be described as "a physical wound or injury, such as a fracture or blow." Major trauma can result in secondary complications such as circulatory shock, respiratory failure and death...
, non-traumatic, and idiopathic
Idiopathic
Idiopathic is an adjective used primarily in medicine meaning arising spontaneously or from an obscure or unknown cause. From Greek ἴδιος, idios + πάθος, pathos , it means approximately "a disease of its own kind". It is technically a term from nosology, the classification of disease...
injury to the long thoracic nerve.
There are numerous ways in which the long thoracic nerve can sustain trauma-induced injury. These include, but are not limited to, blunt trauma (e.g. blow to the neck or shoulder, sudden depression of the shoulder girdle, unusual twisting of the neck and shoulder), repetitive movements (as observed in athletic activities such as weight lifting or sports that involve throwing), and household activities (e.g. gardening, digging, car washing, prolonged abduction of the arms when sleeping, propping up the head to read, etc.). Sometimes, other structures in the body such as inflamed and enlarged subcorocoid or subscapular
Subscapularis muscle
The subscapularis is a large triangular muscle which fills the subscapular fossa and inserts into the lesser tubercle of the humerus and the front of the capsule of the shoulder-joint.-Origin and insertion:...
bursa
Bursa (anatomy)
A bursa is a small fluid-filled sac lined by synovial membrane with an inner capillary layer of slimy fluid . It provides a cushion between bones and tendons and/or muscles around a joint. This helps to reduce friction between the bones and allows free movement...
press on the nerve. Clinical treatments may also cause injury to the long thoracic nerve (iatrogenesis
Iatrogenesis
Iatrogenesis, or an iatrogenic artifact is an inadvertent adverse effect or complication resulting from medical treatment or advice, including that of psychologists, therapists, pharmacists, nurses, physicians and dentists...
from forceful manipulation, mastectomies with axillary node dissection, surgical treatment of spontaneous pneumothorax
Pneumothorax
Pneumothorax is a collection of air or gas in the pleural cavity of the chest between the lung and the chest wall. It may occur spontaneously in people without chronic lung conditions as well as in those with lung disease , and many pneumothoraces occur after physical trauma to the chest, blast...
, post-general anesthesia for various clinical reasons, and electrical shock, amongst others).
Non-traumatic induced injury to the long thoracic nerve includes, but is not limited to, causes such as viral illness (e.g. influenza
Influenza
Influenza, commonly referred to as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae , that affects birds and mammals...
, tonsillitis
Tonsillitis
Tonsillitis is an inflammation of the tonsils most commonly caused by viral or bacterial infection. Symptoms of tonsillitis include sore throat and fever. While no treatment has been found to shorten the duration of viral tonsillitis, bacterial causes are treatable with antibiotics...
-bronchitis
Bronchitis
Acute bronchitis is an inflammation of the large bronchi in the lungs that is usually caused by viruses or bacteria and may last several days or weeks. Characteristic symptoms include cough, sputum production, and shortness of breath and wheezing related to the obstruction of the inflamed airways...
, polio
Poliomyelitis
Poliomyelitis, often called polio or infantile paralysis, is an acute viral infectious disease spread from person to person, primarily via the fecal-oral route...
), allergic-drug reactions, drug overdose, toxic exposure (e.g. herbicides, tetanus
Tetanus
Tetanus is a medical condition characterized by a prolonged contraction of skeletal muscle fibers. The primary symptoms are caused by tetanospasmin, a neurotoxin produced by the Gram-positive, rod-shaped, obligate anaerobic bacterium Clostridium tetani...
), C7 radiculopathy
Radiculopathy
Radiculopathy is not a specific condition, but rather a description of a problem in which one or more nerves are affected and do not work properly . The emphasis is on the nerve root...
, and coarctation of the aorta
Aortic coarctation
Coarctation of the aorta, or aortic coarctation, is a congenital condition whereby the aorta narrows in the area where the ductus arteriosus inserts.-Types:There are three types:...
.
Secondary to serratus anterior palsy, a winged scapula is also caused by trapezius and rhomboid
Rhomboid
Traditionally, in two-dimensional geometry, a rhomboid is a parallelogram in which adjacent sides are of unequal lengths and angles are oblique.A parallelogram with sides of equal length is a rhombus but not a rhomboid....
palsy involving the accessory nerve
Accessory nerve
In anatomy, the accessory nerve is a nerve that controls specific muscles of the shoulder and neck. As part of it was formerly believed to originate in the brain, it is considered a cranial nerve...
and the dorsal scapular nerve
Dorsal scapular nerve
The dorsal scapular nerve arises from the brachial plexus, usually from the plexus root of C5.It provides motor innervation to the rhomboid muscles, which pull the scapula towards the spine and levator scapulae muscle, which elevates the scapula....
, respectively.
Though the most common causes of a winged scapula is due to serratus anterior palsy, and less commonly trapezius and rhomboid palsy, there are still other circumstances that present the ailment. These incidences include direct injuries to the scapulothoracic muscles (i.e. trapezius and rhomboid muscles), and structural abnormalities (e.g. rotator cuff
Rotator cuff
In anatomy, the rotator cuff is the group of muscles and their tendons that act to stabilize the shoulder. The four muscles of the rotator cuff, along with the teres major muscle, the coracobrachialis muscle and the deltoid, make up the seven scapulohumeral muscles of the human body.-Function:The...
pathology, shoulder instability, etc.).
Treatment
Since there are a variety of classifications of winged scapula, there is also more than one type of treatment. Time and occupational therapy or physical therapy is the best treatment if there is weakness of the glenohumeral jointGlenohumeral joint
The glenohumeral joint, or shoulder joint, is a multiaxial synovial ball and socket joint and involves articulation between the glenoid fossa of the scapula and the head of the humerus...
muscles but if the muscles do not contract clinically and symptoms continue to be severe for more than 3–6 months, surgery may be the next choice. Surgery by fixation of the scapula
Scapula
In anatomy, the scapula , omo, or shoulder blade, is the bone that connects the humerus with the clavicle ....
to the rib cage
Rib cage
The rib cage is an arrangement of bones in the thorax of animals. It is formed by the vertebral column, ribs and sternum and encloses the heart and lungs....
can be done for those with isolated scapular winging. Some options are neurolysis (chordotomy), intercostal nerve transfer, scapulothoracic fusion, arthrodesis
Arthrodesis
Arthrodesis, also known as artificial ankylosis or syndesis, is the artificial induction of joint ossification between two bones via surgery. This is done to relieve intractable pain in a joint which cannot be managed by pain medication, splints, or other normally-indicated treatments. The typical...
(scapulodesis), or scapulothoracis fixation without arthrodesis (scapulopexy).
Epidemiology
A winged scapula due to serratus anterior palsy is rare. In one report (Fardin et al.), there was an incidence of 15 cases out of 7,000 patients seen in the electromyographical laboratory. In another report (Overpeck and Ghormley), there was only one case out of 38,500 patients observed at the Mayo ClinicMayo Clinic
Mayo Clinic is a not-for-profit medical practice and medical research group specializing in treating difficult patients . Patients are referred to Mayo Clinic from across the U.S. and the world, and it is known for innovative and effective treatments. Mayo Clinic is known for being at the top of...
. In yet another report (Remak), there were three diagnoses of serratus anterior paralysis throughout a series of 12,000 neurological examinations.
External links
- Illustration at UCSD