What is Shoulder Instability?• Wide variation in diagnosticand treatment criteria evenamong shoulder surgeons.– Chahal, J., Clin. J. Sports Med• With the advances in modernarthroscopic diagnosis andtreatment this may reflect agradual transition from anetiology based diagnosis andtreatment methodology to onethat is based on the anatomicsites of pathology.
What is posterior instability?• Spectrum of disorders and pathology– Acute only 5% of all dislocations• Trauma, Seizure, ElectricalShock• Nearly 50% missed initially– Voluntary• Psychogenic• Learned Behavior– Acquired• Largest group includesmultiple etiologies• Circle Concept of Instability• Multiple sites of concurrentpathology– Glenoid Dysplasia
Diagnosis• Difficult– Pain often the only complaint• Primarily with activity or positional• Flexion, adduction, internal rotation– Instability and Neurological Complaints• More common with underlying laxity/MDI– Spectrum of anatomic lesions• Historically articles have focused on a small subsetof this spectrum.
Diagnosis• No single test reliable– Jerk– Load and Shift– Sulcus– Biceps/SLAP relatedTests– Rotator Cuff– Anterior InstabilityTests