Shoulder Instability Explained: From Diagnosis to Treatment with Dr. Sterett
Shoulder instability is a common condition, particularly among active individuals, and understanding the difference between true instability and simple looseness of the joint is key to proper diagnosis and treatment. Instability is typically what a patient feels such as the shoulder “popping out” or giving way while laxity refers to increased joint motion found on exam that may or may not cause symptoms. Importantly, patients can have instability without measurable laxity, and vice versa, which is why listening closely to a patient’s experience remains one of the most valuable diagnostic tools.
There are several recognized patterns of shoulder instability. Traumatic instability, often referred to as TUBS, usually occurs after an injury and is typically unidirectional with structural damage such as a labral tear. These cases frequently require surgical stabilization, especially in younger or more active patients. In contrast, atraumatic instability, known as AMBRI, is often multidirectional, may affect both shoulders, and is commonly associated with generalized ligamentous laxity. These patients are usually best treated with rehabilitation rather than surgery. A third category, multidirectional instability, involves symptomatic looseness in multiple directions and is often seen in patients who may even be able to voluntarily dislocate their shoulder.
Diagnosis starts with a detailed history and physical exam. Patients may present with pain, a sense of instability, weakness, or loss of function, and sometimes they may not even realize the shoulder has dislocated at the time of injury. A thorough exam evaluates range of motion, strength, and specific instability tests such as the apprehension test, load and shift, and sulcus sign. Comparing the injured shoulder to the opposite side is critical, as is assessing overall joint laxity using tools like the Beighton score. When combined, these findings often provide a clear diagnosis and can even help predict what imaging studies like an MRI will show.
Treatment ultimately depends on the type of instability and the individual patient. Many cases can be successfully managed with targeted physical therapy focused on strengthening and stabilizing the shoulder. However, in traumatic cases or when instability persists despite conservative care, surgical intervention may be recommended. As emphasized in the presentation, the goal is always to choose the right treatment for the right patient, ensuring the best possible outcome and a safe return to activity.
Check out the full presentation here: Shoulder Instability Definitions, Diagnosis and Treatment
