Recurrent Posterior Subluxation
the most common form of posterior instability
most do not present with an initial episode of significant trauma requiring reduction; more commonly, the sensation of the joint slipping posteriorly follows overuse
pain may be the primary presenting feature
can sometimes be demonstrated by muscular contraction (voluntary) or by arm positioning (involuntary).
most provocative test is the jerk test – bringing the arm into flexion and internal rotation, then adducting the shoulder
apprehension is usually absent
most have minimal pain and functional disability, and physiotherapy remains the main focus of treatment, consisting of a rotational and scapular strengthening program.
Pain may ultimately be the primary indication for surgery
Posterior inferior capsular shift – Tibone and Bradley, Neer and Foster
Posterior inferior capsular shift with posterior bone block – Warren
Glenoid osteotomy – Rockwood
Arthroscopic capsular plication – Wolf & Eakin
– an important consideration is the recognition of inferior capsular laxity