Scapular Winging is a clinical syndrome that is caused by a loss of the normal scapular stability that make the inferior border of scapula moves medially or laterally.
Medial Scapular Winging is seen in:
Serratus anterior muscle weakness.
Long thoracic nerve dysfunction.
While Lateral Scapular Winging is seen in:
Trapezius muscle weakness.
Spinal accessory nerve (CN XI) dysfunction.
The Long thoracic nerve can get directly injured during thoracic surgery (first rib resection, introduction of chest drain etc.) or in case of direct trauma of the chest wall. Indirect injury can happen when the arm is overstretched in elevation. When there is no injury in the history, virus infection may be the reason of the nerve lesion
How would you test for winging of scapula?
While standing, have the patient forward flex their arm to 90 degrees and push against a wall (or other stationary object).
What does a positive Scapular Winging Test mean?
It’s Positive if the inferior border of the scapula migrates medially which is called Medial Scapular Winging .
If the inferior boarder of the scapula migrates laterally then it’s called Lateral Scapular Winging.
Scapula is a flat bone that spans from the second rib to the seventh rib and serves as an attachment for 17 muscles. It is anteverted on chest wall approximately 30 degrees relative to the body.
Long thoracic Nerve:
It’s the first branch of the C5-C6-C7 roots of the Brachial Plexus, it’s the motor nerve to the serratus anterior muscle.
It’s 24 cm in length from origin to the serratus anterior muscle, which makes it susceptible to mechanical injury.
Serratus anterior Muscle:
It’s a broad and flat sheet of muscle that originates from the 1-9 ribs and insert into the costal surface of the medial border of the scapula.
Its function is preventing winging of the scapula.
Serratus anterior Muscle is innervated by the Long thoracic Nerve.
The trapezius muscle is the most superficial back muscle. It is a flat triangular muscle that runs from the superior nuchal line and external occipital protuberance of the occipital bone to the spinous process of T12 and is the largest muscle attachment in the body.
Its insertion can be traced from the entire superior aspect of the spine of the scapula, the medial aspect of the acromion, and the posterior aspect of the lateral third of the clavicle.
This muscle traditionally is divided into middle, upper, and lower parts, according to anatomy and function:
The middle part originates from C7 and forms the cervicothoracic part of the muscle.
The lower part, attaching to the apex of the scapular spine, is relatively thin.
The upper part is very thin, and yet it has the most mechanical and clinical importance to the cervical spine.
The innervation for the trapezius comes from the accessory nerve (CN XI) and fibers from the anterior (ventral) rami of the third and fourth cervical spinal nerves.
The different parts of this muscle provide a variety of actions on the shoulder girdle, including elevation and retraction of the scapula.
When the shoulder girdle is fixed, the trapezius can produce ipsilateral side bending and contralateral rotation of the head and neck.
Working together, the trapezius muscles can produce symmetric extension of the neck and head.
In addition, the trapezius muscle can produce scapular adduction (all three parts), and upward rotation of the scapula (primarily the superior and inferior parts).
Scapular Winging Syndrome
This syndrome is characterized by an inability to elevate and/ or lower the arm without the scapula winging or its inferior angle tilting. This syndrome results from a weakness and adaptive shortness of the serratus anterior, with accompanying shortness of the pectoralis minor and scapulohumeral muscles.
Intervention should focus on stretching the pectoralis minor to correct the tilting and serratus anterior for strengthening and retraining.
Campbel’s Operative Orthopaedics 13th Book
Department of Orthopaedics, Physical Medicine and Rehabilitation, David Geffen School of Medicine at UCLA, 1250, 16th St, 7th Floor, Tower Bld, Rm 745, Santa Monica, CA 90404 USA 1