Shoulder: Tight Posterior Capsule

Hi Guys,

Hope your placements are all going well.

During my first placement (Musculoskeletal), I assessed and treated a number of patients who presented with shoulder impingement. To help identify the likely culprit as to why my patient's were experiencing shoulder pain and loss of ROM (in particular ER) detailed investigations were conducted. Some of these included PAM's, GHJ Stability Tests, Muscle Dynamic Stability Tests,
GHJ Impingement Tests, Muscle Length Tests, Muscle Strength Test, Motor Control Examination etc.

Apart form the usual impingement suspects (eg bursa, sup joint capsule, supraspinatus and LH biceps tendon), palpation further revealed a number of clues. In particular many of my patients had anteriorly translated HOH's (normally should be 1/3 of HOH). I know from my studies that if the HOH is excessively anteriorly translated this may contribute to shoulder instability and impingement. My supervisor advised me to check for posterior joint capsule tightness as this often a major cause. I accepted this and researched this topic myself and found that the literature supports this view. However on reflection I don't completely understand how a tight posterior capsule can anteriorly translate the humeral head, visualizing this structure if anything I thought it may posteriorly translate the humeral head.

If anyone can clearly the explain the correlation between a tight post capsule and an anteriorly translated HOH I would like to hear.

Christian.