Shoulder arthroplasty

Stability

• Static
  • Bony anatomy
  • Labrum
  • GH ligament
• Dynamic
  • Concavity compression by cuff and deltoid

Anatomic shoulder

• Replicate normal anatomy
• restore COR
• Restore offset
• Regain ROM

Cuff deficiency

• Superior migration, rocking house phenomenon
• Addressed by Reverse shoulder
  • Glenoid hemisphere
  • Humeral cup
  • Transfer COR medially and inf

Medialisation

• Improved deltoid tension
• Improved ROM
• decreased shear
• Scapular notching
• Decreased ER

Glenoid wear and version

• Walsh classification
• Exentric reaming
• BG/Metal augment
• Interposition and hemiarthroplasty

Approach

• DP
  • D and pectoral
• Anterosuperior approach: anterior and middle deltoid
  • better glenoid exposure
  • preserve subscap

Compli

• Instability 5%
  • Anterior due to subsacp def (pect maj transfer + allograft augment
  • Posterior: convert to RSA
• infection <.5
  • RSA 3.8%
• Fractures

Scapular notching

• RSA
• Decrease by
  • Glenosphere lateralisation
  • Decrease N-S angle
  • eccentric glenosphere
  • inferior tilt of glenosphere

OA

• TSA vs Hemi
• Mitchel et al systematic review
• Better function and reduced revision but increased compli with TSA

PROFER 2

• non surgical vs hemi vs RSA in 3/4 part # proximal humerus