The primary indication for scapulothoracic endoscopy is performance of a bursectomy for a condition called “snapping scapula syndrome.” Snapping scapula is classified according to its etiology: intrinsic or extrinsic (Table 36–1). Extrinsic causes of snapping scapula are those secondary to other primary shoulder pathologies such as acromioclavicular or glenohumeral arthritis and rotator cuffdisease. The intrinsic category comprises anatomical abnormalities and primary idiopathic causes associated with bursitis or trauma. The patients with the less common primary idiopathic type, a diagnosis of exclusion, are the patients who may require scapulothoracic endoscopy after failed conservative treatment. In the lead author’s experience, such procedures have been performed only very rarely. Other than its use in performing a bursectomy, scapulothoracic endoscopy may have a role in treatment of selected anatomical abnormalities, such as an isolated osteochondroma in the scapulothoracic region, although we have not used it for this purpose. Most anatomical lesions have historically been addressed with open techniques.
Primary idiopathic inflammatory or posttraumatic snapping scapula syndrome.
1. Other forms of untreated primary shoulder girdle pathology
2. Most anatomic abnormalities in and around the scapulothoracic articulation
3. Subscapular pain without associated crepitus (relative contraindication)
Retroscapular pain without associated crepitus may result from a variety of causes distinct from the scapulothoracic joint. Etiologies include primary cardiac, intraabdominal, or intrathoracic pathology, thoracic disk herniation, and primary or metastatic neoplasm. Subscapular pain without crepitus is rarely an indication for endoscopy.
1. Posterior and retroscapular shoulder pain.
2. Complaint of scapular snapping or popping—palpable, audible, or both.
3. Patient may note a history of trauma as the inciting event.
4. Repetitive motion may be determined as a cause of an overuse injury.
Secondary to Other Forms of First-Degree Shoulder Girdle Pathology
Rib or scapula fracture malunion
Muscle insertion avulsion or calcification
Primary bone or soft tissue neoplasm
Luschkas tubercle exostosis
Acromioclavicular or glenohumeral arthritis
Rotator cuff disease
Data from Matthews et al (1996).