Multidirectional Instability (MDI)
Atraumatic shoulder instability in multiple directions
Understanding MDI
MDI is characterized by the AMBRII mnemonic: Atraumatic, Multidirectional, often Bilateral, Rehabilitation is primary treatment, Inferior capsular shift if surgery needed, Interval closure.
Key Features: Positive sulcus sign, generalized ligament laxity, bilateral symptoms, gradual onset without specific trauma.
Treatment Protocol
• Rotator cuff strengthening (especially external rotators)
• Scapular stabilization (critical component)
• Proprioceptive training
• Avoid positions of instability
• Core strengthening
Success rate: 80-90% with dedicated program lasting 6+ months
• Arthroscopic capsular plication (tightening)
• Open inferior capsular shift (Neer procedure)
• Rotator interval closure
• Address all directions of instability
