Causes of Static versus Dynamic Winging Static Winging ◗ May be the result of the architecture of the subject, e.g. flat thoracic spine, shortened clavicle, scoliosis ◗ May be muscular, e.g. serratus anterior, or gripping Dynamic Winging – flexion, abduction or both ◗ Serratus anterior weakness (winging occurs before 90° of abduction but very little with flexion) ◗ Lesion to long thoracic nerve (C 5, 6, 7) due to direct blow, compression , backpack, radiation, heavy effort above shoulder, repetitive strain ◗ Trapezius dysfunction (winging begins before 90° abduction; little winging with flexion) ◗ Spinal accessory nerve lesion (cranial nerve XI, C3, 4) due to direct blow, traction injury, brachial plexus lesion ◗ Scapula elevates, adducts, and downwardly rotates ◗ Splinting / bracing of glenohumeral joint ◗ Due to pain, gripping with teres major, pec minor, pec major etc. ◗ Causes reversal of scapulohumeral rhythm: reverses action of rotator cuff to pull the scapula / glenoid toward the humerus and cause winging and tipping ◗ Rhomboid weakness ◗ If unable to adequately use the rhomboid for leverage, then the scapula is moved to position the glenoid under the head of humerus (HOH) and then lever the arm up ◗ Multidirectional instability ◗ Inadequate compression of the HOH in the joint requires another approach to find some stability, so scapula is tucked under the HOH as per above scenarios – Magee, Sahrmann, Watson
Cervical & Thoracic Spines ◗ Neurological and positional cause and effect relationship with upper extremity ◗ Thoracic spine kyphosis causes scapular abduction and downward rotation, restricts end-of-range elevation ◗ Excessive thoracic spine extension causes winging and decreased support ◗ Decreased mobility causes increased strain on glenohumeral joint ◗ Cervical spine neural connection with upper extremity ◗ Breathing is of quintessential importance to proper positioning and functioning of the upper quadrant and especially scalene, pectoralis minor and diaphragm
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