The shoulder joint is a very complex joint with over 25 possible conditions affecting just the soft tissues surrounding the joint. That doesn’t count fractures of the bone or tumors of the soft tissues and/or bone. Despite many studies trying to identify ways to accurately diagnose shoulder problems, we still don’t have it nailed down as to which one test is best for each condition. That would certainly save on the poking and prodding that’s required to figure out what’s wrong.
Many times, the examiner must rely on the history (what happened and how it happened) along with a combination of many tests. Some of the more commonly used tests check for impingement (soft tissue structure gets pinched against the bone or between two surfaces), instability (unstable joint likely to partially or fully dislocate), torn rotator cuff (partial or full-thickness tear), or adhesive capsulitis (frozen shoulder).
You may have heard your doctor mention some of these names: drop-arm sign, shoulder shrug sign, Neer Impingement sign, Hawkins-Kennedy sign, Speed test, Apprehension tests (anterior and posterior), compression test, lift-off test, painful arc sign, cross-body adduction test, resisted extension test, external rotation lag sign, and Whipple Test. So, you can see it was a very thorough collection of tests used in this field.
Research is ongoing trying to find out which test (or small cluster of tests) work best for each individual problem. An accurate diagnosis is important in order to apply the best, right treatment. This is something orthopedic specialists have been working on since the early 1930s! But in the end, sometimes the diagnosis and the treatment occur at the same time through arthroscopic exam and surgery.