Contents

SynopsisCodesLook ForDiagnostic PearlsDifferential Diagnosis & PitfallsBest TestsManagement PearlsTherapyReferences

View all Images (3)

Winged scapula
Other Resources UpToDate PubMed

Winged scapula

Contributors: Abby Ventura, Stephanie E. Siegrist MD
Other Resources UpToDate PubMed

Synopsis

Causes / typical injury mechanism: Scapular winging (SW) arises from weakness of one or more muscles that stabilize the scapula against the posterior thorax. This could result from dysfunction of the muscle itself or the nerve that innervates it.

Classic history and presentation: Patients with SW present with periscapular aching and fatigue and difficulty lifting objects and raising their arm above the head, due to limited ability to abduct and flex the upper extremity. They may have had recent neck or chest wall surgery or trauma, or history of heavy repetitive arm use in sports or occupations. Classically, the patient will present with a visibly protruding scapula, as the weak affected muscle is overpowered by the normal tone of its opponent.

Prevalence: Rare; there is no independent association with age or sex / gender.

Risk factors:

  • Surgery involving the chest wall (eg, lymph node dissection, mastectomy)
  • Occipital lymph node biopsy (spinal accessory nerve crosses the posterior cervical triangle superficially)
  • Penetrating trauma to the neck or thorax
  • Sports, hobbies, or occupations involving collisions or repetitive throwing and heavy overhead use
  • Changes in the bone of the scapula
  • Periscapular soft tissue abnormalities
Pathophysiology: There is no bony attachment between the scapula and thorax; this articulation is comprised of soft tissues that allow rotation and translation of the scapula across the posterior chest wall. The scapula serves as the attachment site for muscles that provide stability and movement to the upper extremity.
  • Gradual / atraumatic onset:
  • Acute onset:
    • Traumatic muscle avulsion
    • Displaced fractures
    • Direct nerve injury from traction, compression, penetrating injury, or surgical dissection involving the neck or chest wall
Grade / classification system: The most common classification used is medial versus lateral.
  • Medial SW is most often due to lesions of the long thoracic nerve (roots C4-C7) and/or dysfunction of the muscle it innervates, the serratus anterior.
    • Lesions to the long thoracic nerve can occur during surgical procedures involving the chest, such as axillary lymph node dissections, mastectomies, or stab wounds.
    • Serratus anterior muscle paralysis can also occur with sports and occupations that involve heavy repetitive arm movements.
  • Lateral SW is typically caused by dysfunction of the trapezius muscle (innervated by the spinal accessory nerve CN XI) or rhomboid muscles (innervated by the dorsal scapular nerve).
    • Lesions to the spinal accessory nerve (CN XI) can occur during neck dissections.

Codes

ICD10CM:
M21.80 – Other specified acquired deformities of unspecified limb

SNOMEDCT:
17211005 – Winged scapula

Look For

Subscription Required

Diagnostic Pearls

Subscription Required

Differential Diagnosis & Pitfalls

To perform a comparison, select diagnoses from the classic differential

Subscription Required

Best Tests

Subscription Required

Management Pearls

Subscription Required

Therapy

Subscription Required

References

Subscription Required

Last Reviewed:04/24/2023
Last Updated:05/17/2023
Copyright © 2024 VisualDx®. All rights reserved.
Winged scapula
Copyright © 2024 VisualDx®. All rights reserved.