Scapular winging occurs when the shoulder blade protrudes abnormally from the back. This visible prominence is common and can frequently be a source of concern. Understanding its causes helps in addressing the condition effectively.
What is Scapular Winging?
The scapula is a flat, triangular bone resting against the back of the rib cage, forming a crucial part of the shoulder girdle. Normally, it lies flush against the chest wall, allowing smooth, coordinated arm movement. Several muscles hold the scapula in place and control its motion.
Primary muscles include the serratus anterior, trapezius, and rhomboids. The serratus anterior originates from the ribs and attaches to the underside of the scapula, firmly pressing it against the rib cage for arm elevation and protraction. The trapezius and rhomboids help retract, elevate, and rotate the scapula. When these muscles lose stability due to weakness or paralysis, the bone can protrude, creating the “winged” appearance. This instability disrupts shoulder movement, potentially causing discomfort.
Everyday Causes
Scapular winging often stems from common factors related to daily habits and muscle function. Poor posture, like prolonged slouching or sitting with rounded shoulders, contributes to this condition. Over time, these postures can lead to muscle imbalances, with some becoming weak and others overly tight.
Muscles stabilizing the scapula against the rib cage, such as the serratus anterior and lower trapezius, may weaken from disuse or improper engagement. Chest muscles like the pectoralis minor can tighten, pulling shoulder blades forward and worsening the issue. Repetitive movements in sports or occupational tasks can also strain or fatigue these stabilizing muscles. Minor muscle strains from unaccustomed activity or improper exercise form can disrupt the balance needed for proper scapular positioning.
Medical Conditions and Injuries
While everyday factors contribute, scapular winging can also result from medical conditions or injuries. Nerve damage is a primary cause for pronounced and persistent winging. Injury to the long thoracic nerve, which controls the serratus anterior, typically leads to medial winging, where the inner border of the shoulder blade protrudes. This nerve injury can occur from blunt trauma, falls, repetitive strain, or viral illnesses.
Another involved nerve is the spinal accessory nerve, which innervates the trapezius. Damage to this nerve often results in lateral winging, characterized by the shoulder blade moving outward and its lower angle rotating away from the spine. Such injuries arise from neck surgeries or direct trauma. Less commonly, dorsal scapular nerve damage can affect the rhomboid muscles, contributing to scapular instability. Direct trauma to the shoulder or upper back, including clavicle fractures or shoulder dislocations, can also disrupt scapular stability.
Path to Recovery
Addressing scapular winging typically involves restoring muscle balance and proper shoulder mechanics. Physical therapy is a central component, emphasizing exercises to strengthen weakened muscles around the shoulder blade. These exercises often target the serratus anterior, rhomboids, and trapezius, improving scapular stabilization. Therapists also incorporate stretches for tight muscles, like the pectoralis minor, to allow a more natural scapular resting position.
Alongside exercises, ergonomic adjustments to daily environments, like workspaces, can help maintain better posture and reduce shoulder muscle strain. Lifestyle modifications promoting active movement and discouraging prolonged static positions are also beneficial. For nerve injuries, recovery can sometimes be spontaneous, though it may take months or up to two years. For severe or persistent cases, medical interventions like bracing may provide support, and in rare instances, surgery might be considered if nerve function does not recover or if there is significant functional limitation. Consulting a healthcare professional is important for an accurate diagnosis and a personalized treatment plan.