There are many different signs and symptoms of various hip conditions. Your description of the limited motion (called internal rotation) on one side is a potential sign of a condition known as femoroacetabular impingement or FAI.
Impingement refers to some portion of the soft tissue around the hip socket getting pinched or compressed. Femoroacetabular tells us the impingement is occurring where the femur (thigh bone) meets the acetabulum (hip socket). There are several different types of impingement. They differ slightly depending on what gets pinched and where the impingement occurs.
But FAI does not have one symptom or one clinical test that tells the physician, “Yes, this person has femoroacetabular impingement FAI)”. Instead, the diagnosis is one of exclusion based on patient history, clinical symptoms, physical examination, and the results of imaging studies (X-rays, MRIs).
We say the diagnosis is one of exclusion because there are other hip problems with similar presentation. The examining physician formulates the diagnosis by excluding other potential causes in order to make the final determination just what is the condition responsible for your patient symptoms.
If this is an ongoing problem that has not resolved in a few weeks, then you should seek a medical evaluation. They physician usually begins with your history (as it relates to this problem) and conducts a step-by-step physical examination. X-rays or other imaging studies may be needed. Only with the combination of these three factors can the final diagnosis be made with certainty.
With some hip problems, there isn’t one test, one symptom, or one clinical finding that confirms the diagnosis. A thorough evaluation is required. Sometimes it becomes very clear what the problem is. In other cases, with patience and persistence, the physician can sort through important points in the patient history. Combining that information with findings from the physical examination and imaging studies will be necessary to make the final diagnosis. The differential diagnosis is often one of exclusion through a process or “ruling out” other hip conditions, one at a time.