A winged scapula (scapula alata) is a skeletal

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

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 The upper Limb (anatomy), limbs or upper extremities are the forelimbs of an upright posture, upright-postured tetrapod vertebrate, extending from the scapulae and clavicles down to and including the digit (anatomy), digits, including all the musc ...

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 Activities of daily living (ADLs) is a term used in healthcare to refer to an individual's daily self-care activities. Health professionals often use a person's ability or inability to perform ADLs as a measure of their Performance status, functi ...

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 (: 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 either side ...

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 terminology, anatomical terms. Motion includes movement of Organ (anatomy), organs, joints, Limb (anatomy), limbs, and specific sections of the body. The terminology used de ...

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 (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 muscle causes the deformation of the back. The serratus anterior 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

rib In vertebrate anatomy, ribs () are the long curved bones which form the rib cage, part of the axial skeleton. In most tetrapods, ribs surround the thoracic cavity, enabling the lungs to expand and thus facilitate breathing by expanding the ...

cage) and normally anchors the scapula against the

rib cage The rib cage or thoracic cage is an endoskeletal enclosure in the thorax of most vertebrates that comprises the ribs, vertebral column and sternum, which protect the vital organs of the thoracic cavity, such as the heart, lungs and great ve ...

. 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 Paralysis (: paralyses; also known as plegia) is a loss of Motor skill, motor function in one or more Skeletal muscle, muscles. Paralysis can also be accompanied by a loss of feeling (sensory loss) in the affected area if there is sensory d ...

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 serratus anterior

. 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 injury or diseases. The term ''Lesion'' is derived from the Latin meaning "injury". Lesions may occur in both plants and animals. Types There is no de ...

s) of 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 An idiopathic disease is any disease with an unknown cause or mechanism of apparent spontaneous origin. For some medical conditions, one or more causes are somewhat understood, but in a certain percentage of people with the condition, the cause ...

injury to the long thoracic nerve. The second category is the lateral winging which is caused by injury of the

spinal 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 nerves ...

. Severe atrophy of the

trapezius The trapezius is a large paired trapezoid-shaped surface muscle that extends longitudinally from the occipital bone to the lower thoracic vertebrae of the human spine, spine and laterally to the spine of the scapula. It moves the scapula and ...

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 Bursa () is a city in northwestern Turkey and the administrative center of Bursa Province. The fourth-most populous city in Turkey and second-most populous in the Marmara Region, Bursa is one of the industrial centers of the country. Most of ...

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 27 ...

from forceful manipulation, mastectomies with

axilla The axilla (: axillae or axillas; also known as the 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 a ...

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 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 dyspnea, shortness of breath. In a minority of cases, a one-way valve is ...

, 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, commonly known as the flu, is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These sympto ...

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 75% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe ...

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

herbicides Herbicides (, ), also commonly known as weed killers, are substances used to control undesired plants, also known as weeds.EPA. February 201Pesticides Industry. Sales and Usage 2006 and 2007: Market Estimates. Summary in press releasMain page f ...

tetanus Tetanus (), also known as lockjaw, is a bacterial infection caused by ''Clostridium tetani'' and 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 l ...

), 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 se ...

, and

coarctation of the aorta Coarctation of the aorta (CoA) 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'' means "pressing or drawing toget ...

. Secondary to serratus anterior palsy, a winged scapula is also caused by trapezius and rhomboid muscle 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, usually derived from the ventral ramus of cervical nerve C5. It provides motor innervation to the rhomboid major muscle, rhomboid minor muscle, and levator scapulae muscle. Dorsal ...

, 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 (SITS muscles) 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 a ...

pathology, shoulder instability, etc.).

Diagnosis

In addition to

history History is the systematic study of the past, focusing primarily on the Human history, human past. As an academic discipline, it analyses and interprets evidence to construct narratives about what happened and explain why it happened. Some t ...

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 fractures.

Computed tomography A computed tomography scan (CT scan), formerly called computed axial tomography scan (CAT scan), is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers or ...

(CT) or

magnetic resonance imaging Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to generate pictures of the anatomy and the physiological processes inside the body. MRI scanners use strong magnetic fields, magnetic field gradients, and ...

(MRI) are rarely indicated, but may be useful to rule out certain diagnoses if suspected, such as

neurofibromatosis Neurofibromatosis (NF) refers to a group of three distinct genetic conditions in which tumors grow in the nervous system. The tumors are non-cancerous (benign) and often involve the skin or surrounding bone. Although symptoms are often mild, e ...

-related injury,

intervertebral disc disorder An intervertebral disc (British English), also spelled intervertebral disk (American English), lies between adjacent vertebrae in the vertebral column. Each disc forms a fibrocartilaginous joint (a symphysis), to allow slight movement of the vert ...

, 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 serratus anterior, 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 Physical therapy (PT), also known as physiotherapy, is a healthcare profession, as well as the care provided by physical therapists who promote, maintain, or restore health through patient education, physical intervention, disease preventio ...

constitutes treatment options if there is weakness of the glenohumeral 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) 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 (anatomy), insertion of a tendon is moved, but the origin (anatomy), origin remains in the same location. Tendon transfer involves redistribution of muscle power, not recreation. Tend ...

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 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 Mayo Clinic () is a Nonprofit organization, private American Academic health science centre, academic Medical centers in the United States, medical center focused on integrated health care, healthcare, Mayo Clinic College of Medicine and Science ...

. 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