Snapping scapula syndrome (SSS), or scapulothoracic bursitis, is a rare cause of shoulder pain and dysfunction. The scapula plays an important role in the function of the shoulder girdle and upper extremity by providing a stable base for glenohumeral motion.
Unlike most other joints in the body, however, the scapulothoracic joint is inherently incongruent and lacks features such as a synovial lining or cartilaginous inter- face at its articulation. Instead, the anterior scapula glides over the convex thoracic wall with several bursal and soft-tissue planes interposed between the bony surfaces.1 Because the only scapular attachments to the axial skeleton are through the acromioclavicular and sternoclavicular joints, the scapula is stabilized through dynamic control of the periscapular musculature. Any alterations in the normal anatomy or kinematics of the scapula, chest wall, or surrounding tissues can therefore result in pathologic irritation of the subscapular bursa or fibrosis of the bursa, leading to crepitus or snapping of the scapulothoracic joint. Recent literature has suggested that patients with anterior angulation of the medial scapula in the axial plane are at greater risk of having SSS.2 However, it remains unclear if the bony morphology of the scapula affects the patients’ functional outcome. As with other musculoskeletal disorders, it has been postulated that there is also a psychological profile or tendency that is associated with this disorder.
Initial nonoperative treatment is successful in most patients and should include physical therapy, anti-inflammatory medications, and activity modification. Corticosteroid injections can also be used as both a diagnostic and therapeutic modality. For patients who do not respond well to extensive conservative management, surgical intervention may be considered. Since the first description of arthroscopic bursectomy with partial scapulectomy for SSS in 1999 by Harper there have been limited outcome studies. These have reported good to excellent clinical outcomes, although prior data are limited to case reports or small case series.8 More recently, arthroscopic approaches have been developed, allowing for symptomatic bursal debridement and bony resection through a minimally invasive approach. Although technically challenging, arthroscopy offers additional ad- vantages of preservation of muscular attachments, improved cosmetic appearance, and faster recovery times.
Although our knowledge of SSS and associated surgical techniques continues to evolve, there is limited information in the current literature regarding patient- reported outcomes after arthroscopic treatment. The purpose of this study was to investigate clinical outcomes after primary and revision arthroscopic treatment for SSS and identify predictive factors associated with outcomes.