Winged Scapula review

A winged scapula involves disruption of the spinal accessory nerve or the long thoracic nerve. The spinal accessory nerve, also known as cranial nerve 11, provides nerve innervation to the trapezius muscle and the sternocleidomastoid (SCM) (1). The trapezius aids in lateral scapula rotation and assists the glenoid in motion during abduction (4). Most common causes of injury to the nerve include trauma, nerve compression, or nerve traction injury (1).

Medial scapula winging (4)

Injury to the long thoracic nerve, which originates from C5-7, will also lead to scapular winging (3). The long thoracic nerve innervates the serratus anterior, which is a muscle that primarily acts to stabilize the scapula during abduction (3). Similar mechanisms of injury can affect the long thoracic nerve including nerve traction, nerve compression, and infection (3). The long thoracic nerve is at especially high risk of compression/traction injury due to its superficial route at the lateral chest wall (4).

Long thoracic nerve innervation of the serratus anterior (6)

Patients with neuropraxia to the accessory or long thoracic nerve typically complain of shoulder heaviness (1). They may also complain of difficulty playing overhead sports and pain around the scapula (4). In patients with spinal accessory nerve dysfunction due to trapezius muscle dysfunction, patients will strain their levator scapula and rhomboids to compensate, causing pain and muscle spasm (5).

On physical exam, those who have experienced chronic denervation may have a winged scapula present (1). There may also be limitations in the shoulder range of motion primarily with abduction (2). Providers will also need to evaluate for trapezius atrophy and a depressed shoulder girdle (2). A patient who has difficulty shrugging their shoulders is thought to have an accessory nerve injury verse difficulty with shoulder flexion, which is more suggestive of long thoracic nerve injury (4). Providers should also assess whether the inferior angle of the scapula is rotated medially or laterally (4). Lateral rotation suggests accessory nerve injury and medial rotation suggests long thoracic nerve injury (4).

Lateral scapula winging (4)

 One special test to assess for accessory nerve injury is the scapula flip sign (2). The patient is placed with their arm at their side and elbow flexed to 90 degrees and holding a straight rod (2). Then, the provider will have the patient preform resisted glenohumeral external rotation (2). A positive test is when the medial scapular border lifts off the thoracic wall (2).

Positive scapula flip sign (2)

An electromyography can also be performed to assess nerve innervation of the trapezius and rhomboid muscle (2,4).  

Typical first line treatment for a winged scapula is conservative (1). Patients should avoid any sports activity that involves use of the shoulder girdle (1). A referral to physical therapy is also appropriate so that electrical stimulation of the muscle and muscle strengthening can be started (1). Physical therapy will also help prevent the development of secondary adhesive capsulitis (5).

There is not a clear consensus on the use of a thoracic brace during physical therapy (3). Most patients find the brace intrusive, so compliance is lacking (3). Most patients will have a full recovery within one year (1). However, recovery on average only takes 6-9 months (4). There are surgical options for difficult to treat cases, including nerve reconstruction and neurolysis (1). For patients who have symptoms that last beyond 1-2 years, a dynamic muscle transfer can be considered (4).

Early diagnosis of a winged scapula is difficult. Patients will present with symptoms similar to adhesive capsulitis and a frozen shoulder. Diagnosis becomes clearer when chronic denervation leads to a winged scapula. The most common cause is a nerve traction or compression injury, and they will commonly resolve within one year with physical therapy.

By Gregory Ruin, DO
rubinsportsmed.com

References

1)      Anass, Adnine, et al. “Weightlifting Induced Spinal Accessory Nerve Palsy and Winged Scapula: A Case Report.” Sports Health, Jan. 2024, p. 19417381231219218. PubMed, https://doi.org/10.1177/19417381231219218.

2)      Kelley, Martin J., et al. “Spinal Accessory Nerve Palsy: Associated Signs and Symptoms.” Journal of Orthopaedic & Sports Physical Therapy, vol. 38, no. 2, Feb. 2008, pp. 78–86. DOI.org (Crossref), https://doi.org/10.2519/jospt.2008.2454.

3)      Tibaek, Sigrid, and Janne Gadsboell. “Scapula Alata: Description of a Physical Therapy Program and Its Effectiveness Measured by a Shoulder-Specific Quality-of-Life Measurement.” Journal of Shoulder and Elbow Surgery, vol. 24, no. 3, Mar. 2015, pp. 482–90. PubMed, https://doi.org/10.1016/j.jse.2014.07.006.

4)      Meininger, Alexander K., et al. “Scapular Winging: An Update.” The Journal of the American Academy of Orthopaedic Surgeons, vol. 19, no. 8, Aug. 2011, pp. 453–62. PubMed, https://doi.org/10.5435/00124635-201108000-00001.

5)      Kuhn, J. E., et al. “Scapular Winging.” The Journal of the American Academy of Orthopaedic Surgeons, vol. 3, no. 6, Nov. 1995, pp. 319–25. PubMed, https://doi.org/10.5435/00124635-199511000-00002.

 

6)      Safran, Marc R. “Nerve Injury about the Shoulder in Athletes, Part 2: Long Thoracic Nerve, Spinal Accessory Nerve, Burners/Stingers, Thoracic Outlet Syndrome.” The American Journal of Sports Medicine, vol. 32, no. 4, June 2004, pp. 1063–76. PubMed, https://doi.org/10.1177/0363546504265193.