questions
0

Scapulothoracic Crepitus

Author:
Topic updated on 02/16/16 4:37pm
Introduction
  • Scapulothoracic crepitus, or snapping scapula syndrome, manifests as pain at the scapulothoracic junction with overhead activity. 
  • Pathophysiology
    • predisposing abnormal anatomy 
      • 6% of scapulae have some superomedial hooking
      • malunion of scapula or rib fractures
      • history of resection of 1st rib for thoracic outlet syndrome
    • overuse with normal anatomy
    • inflammation from overuse results in chronic inflammation, causing bursal fibrosis, bursitis, snapping
    • bony or soft tissue masses
      • osteochondroma 
      • elastofibroma dorsi 
        • a benign soft tissue tumor
      • scapular chondrosarcoma
  • Associated conditions
    • Scoliosis, kyphosis
    • scapulothoracic dyskinesis
Anatomy
  • Osteology - Scapula
    • spans ribs 2 to 7
    • three borders (superior, lateral, medial)
    • three angles (superomedial, inferomedial, lateral)
    • no direct bony articulation
    • no true synovial articulation
  • Muscles
    • trapezius
    • serratus anterior
    • subscapularis 
    • levator scapulae
    • rhomboids
    • supraspinatus
    • infraspinatus
    • teres minor
    • teres major
    • triceps brachii (long head)
    • biceps brachii 
    • coracobracialis
    • deltoid
    • pectoralis minor
    • latissimus dorsi (small slip of origin)
    • omohyoid
  • Ligaments
    • transverse scapular ligament - separates suprascapular artery (above) from suprascapular nerve (below, in suprascapular notch)
  • Blood Supply 
    • dorsal scapular artery runs deep to rhomboids and levator 1 to 2 cm medial to scapula
  • Bursae  
    • Anatomic
      • infraserratus
      • supraserratus
    • Adventitial (pathologic)
      • near superior or inferior angles
      • inconsistently identified
Presentation
  • History
    • presentation ranges from mild discomfort to significant disability
    • trauma and overuse have both been reported
  • Symptoms 
    • patient complains of "popping" of scapula
    • painful crepitus with elevation of arm
    • pain relieved with stabilization of scapula
  • Physical exam
    • fixed or postural kyphosis may be present
    • tenderness or fullness of symptomatic bursa
    • ask patient to demonstrate symptomatic motions
    • passive scapulothoracic motion by examiner may also reproduce crepitus
    • scapulothoracic dyskinesis may be present  
      • evaluate for winging
      • test muscle strength 
        • trapezius
        • serratus
        • rhomboids
        • levator
        • latissimus
Imaging
  • Radiographs
    • recommended
      • AP, lateral and axillary 
    • findings
      • look for osseous abnormalities
  • CT scan
    • indications
      •  osseous lesion on plain radiographs
  • MRI
    • indications
      • soft tissue masses
      • inflamed bursae
Studies
  • Diagnostic injections
    • selective injection of local anesthetic and/or corticosteroid to point of maximal tenderness can be diagnostic and therapeutic
Differential
  • Cervical pathology
    • can be referred to shoulder girdle
Treatment
  • Nonoperative 
    • indications
      • first line of treatment
      • no mass or aggressive lesion
    • modalities
      • NSAIDs
      • scapular strengthening exercises, postural training, activity modification
      • local corticosteroid injections 
  • Operative  
    • bursectomy (open or arthroscopic), resection of osseous lesion, resection of scapular border
      • indications
        • cases refractory to nonoperative treatment
      • outcomes
        • improvement in symptoms reported with both open and arthroscopic
        • better results in patients who responded well to injection
        • incomplete resolution of symptoms common despite improvement
        • better results with addition of partial scapulectomy (vs bursectomy alone)
Techniques
  • Open
    • position
      • prone, extremity draped free
    • approach
      • vertical incision over medial border of scapula, centered on symptomatic bursa
      • trapezius split in line with fibers
      • rhomboids and levator elevated subperiosteally
    • technique
      • bursa excised
      • angle of scapula can be excised
      • detached muscles repaired through drill holes
    • postoperative care
      • sling immediate post op
      • must protect repaired muscle attachments
        • immobilize x 4 weeks
        • active motion at 8 weeks
        • strengthening at 12 weeks
    • pros and cons
      • pros: wide exposure
      • cons: morbid
  • Arthroscopic
    • position
      • prone, extremity draped free, arm in maximum internal rotation with hand over lumbar spine
    • approach
      • portals: 3 cm medial to medial border of scapula (avoids dorsal scapular nerve and vessels) and below scapular spine (avoids spinal accessory nerve)
        • superior (Bell's) portal: junction of medial one third and lateral two thirds of superior border of scapula
      • trochar as parallel to chest wall as possible
    • technique
      • skeletonize superomedial angle with cautery
      • resect superomedial angle if desired using burr
      • can place spinal needle at superior scapular border to mark lateral limit of resection
    • postoperative care
      • sling immediate post op used for comfort x 1 week
      • active motion and strengthening based on tolerance
    • pros and cons
      • pros: no muscle detachment
      • cons: technically demanding
Complications
  • Neurovascular injury
    • suprascapular nerve and vessels
    • dorsal scapular nerve and vessels
    • spinal accessory nerve
  • Chest wall penetration
    • pneumothorax
 


 

Please Rate Educational Value!
3.0
Average 3.0 of 9 Ratings

Qbank (0 Questions)




Videos

video
Educational video describing the condition known as snapping scapula syndrome an...
8/21/2013
1001 views
4
See More Videos

Groups


Evidence



Topic Comments