Scapular winging occurs when the shoulder blade (scapula) visibly protrudes from the back, failing to lie flat against the rib cage. This abnormal positioning creates a “winged” appearance, which can be both noticeable and functionally debilitating. The condition is often treatable through targeted exercises and medical interventions. This article details the causes of scapular winging and the steps used to restore normal shoulder function.
Understanding Scapular Winging
The scapula is a flat, triangular bone that serves as the base for the entire shoulder complex, contributing significantly to arm movement and stability. It is not directly connected to the rib cage by a joint but rather “floats,” held in place by a dynamic balance of surrounding muscles. This unique arrangement allows for a wide range of motion, with the scapula gliding and rotating against the back of the chest wall. The collective movement of the arm bone and the shoulder blade is known as the scapulohumeral rhythm.
Winging occurs when the muscular anchors fail, causing the medial or inner border of the scapula to lift away from the thoracic wall. This mechanical failure disrupts the shoulder’s natural rhythm, leading to difficulty with everyday tasks. Patients frequently experience a reduced ability to lift the arm overhead, perform pushing motions, and sometimes report chronic pain or a sensation of instability in the shoulder. A common diagnostic observation is the clear protrusion of the bone when the patient pushes against a wall.
Primary Causes of Winging
The root cause of scapular winging typically involves weakness or paralysis in one of the primary stabilizing muscles due to nerve damage. The most common form is medial winging, which results from a dysfunction of the serratus anterior muscle. This muscle is innervated by the long thoracic nerve, and when the nerve is damaged, the muscle cannot hold the shoulder blade flat against the chest wall. Injury to this nerve can occur from blunt trauma, repetitive strain, or during certain surgical procedures in the chest area.
Another significant cause is lateral winging, which is associated with paralysis of the trapezius muscle. The trapezius is controlled by the spinal accessory nerve, and damage to this nerve often results in the shoulder drooping downward and the scapula rotating abnormally. Less frequently, the rhomboid muscles, supplied by the dorsal scapular nerve, can be involved, contributing to the winging pattern. Traumatic injuries like dislocated shoulders, direct blows to the shoulder or neck, and even viral infections that cause nerve inflammation can all precede the onset of this condition.
Non-Surgical Treatment Approaches
The primary treatment for scapular winging, especially in non-traumatic cases, is a dedicated program of physical therapy and rehabilitation. A physical therapist will first identify which specific muscle is impaired and then develop a tailored regimen focused on restoring strength and coordination. This conservative approach is often successful, particularly when the underlying nerve may recover spontaneously, which can take anywhere from six to twenty-four months.
Therapy begins with exercises aimed at improving scapular stabilization, teaching the patient to consciously control the shoulder blade’s movement. Initial exercises may include gentle isometric contractions or simple movements like the “push-up plus,” which specifically targets the protracting action of the serratus anterior muscle. Strengthening the weakened muscles is progressed through resistance exercises, such as performing a “banded bear hug” to challenge the serratus anterior in its natural function.
The plan also incorporates stretching for opposing, often tight, muscle groups, such as the chest muscles, to ensure proper posture and muscle balance. Wall slides and scapular retractions with light resistance bands are common exercises used to improve the coordinated movement of the shoulder blade. Consistency is paramount, and a successful recovery depends on the patient’s adherence to the prescribed exercises over many months to rebuild the necessary neuromuscular control.
When Professional Intervention is Required
If conservative treatment fails to produce significant improvement in function and pain after a period of 6 to 12 months, or if the initial cause was a severe traumatic injury, professional intervention may be considered. Diagnosis confirmation often involves specialized testing like electromyography (EMG) and nerve conduction studies (NCS). These tests assess the electrical activity of the muscles and the speed of nerve signals, helping to pinpoint the exact location and severity of any underlying nerve damage.
Medical Management
Non-exercise medical treatments may include pain management with anti-inflammatory medications. Temporary bracing can be used to support the shoulder blade during the recovery process.
Surgical Options
In cases where the nerve compression is clearly identified and does not resolve, surgical options become necessary. Procedures can involve nerve decompression to relieve pressure on the damaged nerve or a nerve transfer, where a healthy nerve is redirected to re-innervate the paralyzed muscle.
For chronic cases with permanent nerve damage, a muscle transfer may be performed, such as moving a portion of the pectoralis major muscle to substitute for the lost function of the serratus anterior. Scapulothoracic fusion, which involves surgically attaching the scapula to the ribs, is typically reserved as a last resort for severe, debilitating winging when all other options have failed. An orthopedic surgeon specializing in the shoulder or a peripheral nerve surgeon will determine the most appropriate course of action.