A winged scapula (scapula alata) is a skeletal

medical condition A disease is a particular abnormal condition that negatively affects the structure or function of all or part of an organism, and that is not immediately due to any external injury. Diseases are often known to be medical conditions that a ...

in which the shoulder blade protrudes from a person's back in an abnormal position. In rare conditions it has the potential to lead to limited functional activity in the upper extremity to 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 Activity may refer to: * Action (philosophy), in general * Human activity: human behavior, in sociology behavior may refer to all basic human actions, economics may study human economic activities and along with cybernetics and psychology may s ...

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 The scapula (plural scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on eith ...

sticking straight out from the back. Scapular winging has been observed to disrupt scapulohumeral rhythm, contributing to decreased

flexion Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relativ ...

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.

Signs and symptoms

Scapula Winging in Long Thoracic Nerve Palsy

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 Facioscapulohumeral muscular dystrophy (FSHD) is a type of muscular dystrophy, a group of heritable diseases that cause degeneration of muscle and progressive weakness. Per the name, FSHD tends to sequentially weaken the muscles of the face, ...

(FSHD), 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 The serratus anterior is a muscle that originates on the surface of the 1st to 8th ribs at the side of the chest and inserts along the entire anterior length of the medial border of the scapula. The serratus anterior acts to pull the scapula fo ...

muscle causes the deformation of the back. The

muscle attaches to the medial anterior aspect of the

(i.e. it attaches on the side closest to the spine and runs along the side of the scapula that faces the ribcage) and normally anchors the scapula against the

rib cage The rib cage, as an enclosure that comprises the ribs, vertebral column and sternum in the thorax of most vertebrates, protects vital organs such as the heart, lungs and great vessels. The sternum, together known as the thoracic cage, is a sem ...

. 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 The long thoracic nerve (external respiratory nerve of Bell; posterior thoracic nerve) innervates the serratus anterior muscle. Structure The long thoracic nerve arises from the anterior rami of the C5, C6, and C7 cervical spinal nerve. T ...

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 FSHD, 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

Winging of the scapula is divided into two categories, medial and lateral, according to the direction of winging. Medial winging is more common, being caused by

paralysis. This is typically due to damage (i.e.

lesion A lesion is any damage or abnormal change in the tissue of an organism, usually caused by disease or trauma. ''Lesion'' is derived from the Latin "injury". Lesions may occur in plants as well as animals. Types There is no designated classif ...

s) of the

. 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 An idiopathic disease is any disease with an unknown cause or mechanism of apparent spontaneous origin. From Greek ἴδιος ''idios'' "one's own" and πάθος ''pathos'' "suffering", ''idiopathy'' means approximately "a disease of its own kin ...

injury to the long thoracic nerve. The second category is the lateral winging which is caused by injury of the spinal accessory nerve. Severe atrophy of the trapezius is seen with accidental damage to the spinal accessory nerve during lymph node biopsy of the neck. 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), excessive compression of the shoulder area by straps (see backpack palsy), and various 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 subcoracoid or subscapular bursa press on the nerve. Clinical treatments may also cause injury to the long thoracic nerve (

iatrogenesis Iatrogenesis is the causation of a disease, a harmful complication, or other ill effect by any medical activity, including diagnosis, intervention, error, or negligence. "Iatrogenic", ''Merriam-Webster.com'', Merriam-Webster, Inc., accessed 2 ...

from forceful manipulation,

mastectomies Mastectomy is the medical term for the surgical removal of one or both breasts, partially or completely. A mastectomy is usually carried out to treat breast cancer. In some cases, women believed to be at high risk of breast cancer have the operat ...

with

axilla The axilla (also, armpit, underarm or oxter) is the area on the human body directly under the shoulder joint. It includes the axillary space, an anatomical space within the shoulder girdle between the arm and the thoracic cage, bounded superior ...

node In general, a node is a localized swelling (a "knot") or a point of intersection (a vertex). Node may refer to: In mathematics * Vertex (graph theory), a vertex in a mathematical graph *Vertex (geometry), a point where two or more curves, lines ...

dissection, surgical treatment of spontaneous

pneumothorax A pneumothorax is an abnormal collection of air in the pleural space between the lung and the chest wall. Symptoms typically include sudden onset of sharp, one-sided chest pain and shortness of breath. In a minority of cases, a one-way valve i ...

, 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 Tonsillitis is inflammation of the tonsils in the upper part of the throat. It can be acute or chronic. Acute tonsillitis typically has a rapid onset. Symptoms may include sore throat, fever, enlargement of the tonsils, trouble swallowing, and en ...

bronchitis Bronchitis is inflammation of the bronchi (large and medium-sized airways) in the lungs that causes coughing. Bronchitis usually begins as an infection in the nose, ears, throat, or sinuses. The infection then makes its way down to the bronchi. ...

polio Poliomyelitis, commonly shortened to polio, is an infectious disease caused by the poliovirus. Approximately 70% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe s ...

), allergic-drug reactions, drug overdose, toxic exposure (e.g. herbicides,

tetanus Tetanus, also known as lockjaw, is a bacterial infection caused by ''Clostridium tetani'', and is characterized by muscle spasms. In the most common type, the spasms begin in the jaw and then progress to the rest of the body. Each spasm usually ...

), C7

radiculopathy Radiculopathy, also commonly referred to as pinched nerve, refers to a set of conditions in which one or more nerves are affected and do not work properly (a neuropathy). Radiculopathy can result in pain (radicular pain), weakness, altered sens ...

, and

coarctation of the aorta Coarctation of the aorta (CoA or CoAo), also called aortic narrowing, is a congenital condition whereby the aorta is narrow, usually in the area where the ductus arteriosus (ligamentum arteriosum after regression) inserts. The word ''coarctation' ...

. Secondary to

palsy, a winged scapula is also caused by trapezius and

rhomboid muscle The rhomboid muscles (), often simply called the rhomboids, are rhombus-shaped muscles associated with the scapula. There are two rhomboid muscles on each side of the upper back: * Rhomboid major muscle * Rhomboid minor muscle The large rhom ...

palsy involving the

accessory nerve The accessory nerve, also known as the eleventh cranial nerve, cranial nerve XI, or simply CN XI, is a cranial nerve that supplies the sternocleidomastoid and trapezius muscles. It is classified as the eleventh of twelve pairs of cranial nerv ...

and the

dorsal scapular nerve The dorsal scapular nerve is a branch of the brachial plexus. It supplies rhomboid major muscle, rhomboid minor muscle, and levator scapulae muscle. It causes the scapula to be moved medially towards the vertebral column. Dorsal scapular ne ...

, 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 The rotator cuff is a group of muscles and their tendons that act to stabilize the human shoulder and allow for its extensive range of motion. Of the seven scapulohumeral muscles, four make up the rotator cuff. The four muscles are the supraspi ...

pathology, shoulder instability, etc.).

Diagnosis

In addition to

history History (derived ) is the systematic study and the documentation of the human activity. The time period of event before the invention of writing systems is considered prehistory. "History" is an umbrella term comprising past events as well ...

and

exam An examination (exam or evaluation) or test is an educational assessment intended to measure a test-taker's knowledge, skill, aptitude, physical fitness, or classification in many other topics (e.g., beliefs). A test may be administered verba ...

, it has been recommended to perform

projectional radiography Projectional radiography, also known as conventional radiography, is a form of radiography and medical imaging that produces two-dimensional images by x-ray radiation. The image acquisition is generally performed by radiographers, and the images a ...

of the neck, chest, shoulder, and thoracic inlet to rule out structural abnormalities such as malunited or

greenstick fracture A greenstick fracture is a fracture in a young, soft bone in which the bone bends and breaks. Greenstick fractures occur most often during infancy and childhood when bones are soft. The name is by analogy with green (i.e., fresh) wood which simil ...

s. Computed tomography (CT) or magnetic resonance imaging (MRI) are rarely indicated, but may be useful to rule out certain diagnoses if suspected, such as

neurofibromatosis Neurofibromatosis (NF) is a group of three conditions in which tumors grow in the nervous system. The three types are neurofibromatosis type I (NF1), neurofibromatosis type II (NF2), and schwannomatosis. In NF1 symptoms include light brown sp ...

-related injury, intervertebral disc disorder,

, and

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

Treatment

There are a variety of classifications for winged scapula, and likewise several treatment options. Strength training, particularly of the

, may be recommended as this muscle is responsible for holding the medial scapula close to the rib cage. In more severe cases, physical therapy can help by strengthening related muscles. Physical therapy constitutes treatment options if there is weakness of the

glenohumeral joint The shoulder joint (or glenohumeral joint from Greek ''glene'', eyeball, + -''oid'', 'form of', + Latin ''humerus'', shoulder) is structurally classified as a synovial ball-and-socket joint and functionally as a diarthrosis and multiaxial joint ...

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. Physical therapy for a winged scapula will usually incorporate exercises aimed at strengthening the serratus anterior. The push-up plus (PUP) exercise is one of the most commonly prescribed for strengthening the serratus anterior. The push-up plus is usually done in either a push-up position either against a wall or progressed to the floor. Full scapular protraction (the plus) is added after full elbow extension at the end of the usual push-up exercise. The plus phase during the PUP exercise has been shown to elicit the highest average serratus anterior electromyographic (EMG) activity when compared with other SA-activating and closed kinetic chain exercises. Before and after Scapula-to-scapula scapulopexy FSHD

Before and after Scapula-to-scapula scapulopexy FSHD

Surgical options include neurolysis (

chordotomy Cordotomy (or chordotomy) is a surgical procedure that disables selected pain-conducting tracts in the spinal cord, in order to achieve loss of pain and temperature perception. This procedure is commonly performed on patients experiencing severe ...

) and intercostal nerve transfer if a nerve lesion is the cause of winging. For scapular winging not amenable to nerve repair,

tendon transfer A tendon transfer is a surgical process in which the insertion of a tendon is moved, but the origin remains in the same location. Tendon transfer involves redistribution of muscle power, not recreation. Tendons are transferred at the distal attac ...

is an option. Pectoralis major transfer can be done for isolated serratus anterior palsy, and an Eden-Lange procedure can be done for isolated trapezius palsy. When tendon transfer is not an feasible, such as in the case of muscular dystrophy or multiple muscular deficits, remaining options include scapulothoracic fusion (also known as scapulodesis), which induces bony fusion between the scapula and the rib cage, and scapulothoracic fixation without arthrodesis (scapulopexy). Even though scapulothoracic fusion has been shown to have successful outcomes, complications were present in over 40% of the 130 patients observed by Kord et al.

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 Clinic. In yet another report (Remak), there were three diagnoses of serratus anterior paralysis throughout a series of 12,000 neurological examinations.

References

External links

{{Acquired musculoskeletal deformities Musculoskeletal disorders Peripheral nervous system disorders