Hello, thank you for letting us present our research. So heat micro-instability, I want to give you some background because it's a new subject that each one of us has a different perspective. You can find our disclosures. So hip microinstability is probably an established diagnosis by now, but it's poorly defined. And it has been described as the abnormal motion of the femur in relationship to the acetabulum. But we don't know how much is abnormal. So if we want to talk about the new diagnosis, it has to have some clinical consequences. And it all comes down to the cartilage overload and eventually hip osteoarthritis. So for some patients, this micro motion within the hip joint might be acceptable. And we believe that the problem starts when this micro motion causes overload to the cartilage of the acetabulum and the femoral head. Hip microinstability has been associated with various problems, and each one of them includes all the structures around the hip joints, both the soft tissues and the bones. So labral pathology, ligamentum teres lesions, capsular defects, periarticular hip muscles problems, FAI, hip dysplasia, and extensive osteoarthritis can probably cause a micro motion that we might see as problematic. However, we need to know if this causes symptoms or if the cartilage is being overloaded in order to decide whether we need to treat it or not. And here you can see the micro motion of the hip that we don't know if it's bad or good or okay. But these models can show us how the cartilage behaves. So if a patient has cartilage overload and symptoms, then we might be able to talk about a new diagnosis. Previous studies have shown various tests that can probably help us diagnose clinically hip microinstability, with the most specific being the Braun instability test. And these are based on cadaveric and clinical studies from Dr. Domb and Dr. Safran and Dr. No and various other researchers around the globe. Our purpose though was to see the diagnostic performance of the hip dial test in patients who have FAI and labral pathology but who do not have generalized tissue laxity or acetabular dysplasia. And that's because previous studies always focused on the hip capsule and whether we stretch it or not. And they're usually done in dancers or other populations that are having dysplastic hips. We looked retrospectively in our database from 2005 to 2015, and we included patients that were 18 years or older and who underwent primary hip arthroscopy for FAI with uncomplicated labral tear. We excluded patients who were younger than 18 years, who had previous hip procedures, who had Bayton score four or greater, acetabular dysplasia defined as LCA 20 or less degrees, complex labral tears, and radiographic joint space two millimeters or more on the APX ray. We divided our patients in three groups. First, there were patients who had FAI and they reported a feeling of instability when they came in. The second group was patients who had FAI and they had capsular insufficiency diagnosed intraoperatively. And the third group was patients who had FAI and reported hip instability, but they also had capsular insufficiency diagnosed during surgery. We looked into the diagnostic performance of the hip dial tests. What we found that was in the third group, so when a patient came in and reported feelings of instability and then their capsule was deficient in surgery, the hip dial test was very specific and its specificity was 96.9%. The strengths of this study is we tried to keep in a realistic patient population because most of our patients have FAI and labral tears, but not all of them are dysplastic or have dyslaxia. And the other strength was that we excluded those that were lax and those that were dysplastic as well. The limitations, we didn't do cartilage overload studies in all patients. The Baton's criteria are not validated in the adult population, but that's what we had in our database. And we did not do reliability testing because we will try to do it as a multicenter study to avoid any bias. So in conclusion, FAI alone can be associated with hip micro-instability and the hip dial test is one tool that we can probably use before the surgery to decide if we want to close the capsule or leave it open during hip arthroscopy. Thank you.

hip micro-instability

excessive motion

cartilage overload

FAI

hip dial test