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In this edition focused on hip arthroscopy and conditions that typically affect the athlete, the included papers are of elegant design and precise methods. Clearly, hip and groin injuries are particularly limiting in sports and are a common cause in diminished quality of life and ability to participate in sporting activity [4]. From these studies, we learn so much about how well what we do surgically works and naturally…how much we still need to learn to understand conditions that affect the hip. Several papers address morphology associated with femoroacetabular impingement (FAI). In particular, the alpha angle is an important measure of aberrant morphology of the femoral head and neck junction [8]. The included papers suggest that this measure may be for developmental in etiology when elevated, predictive of range of motion when examining athletes and perhaps associated with intra-articular damage, particularly of chondro-labral injury [2]. At the same time, this same measure (alpha angle) may not predict outcomes following arthroscopic correction of FAI in the mid-term though in general return to sports activity is high in athletes [3]. This apparent contradiction suggests there is much to learn about the morphology of impingement and predictors of good outcomes. Furthermore, the importance of cartilage status is highlighted in this edition as well as how global FAI as a condition truly is in a study documenting this morphology in an Asian population suggesting FAI is a global phenomenon.

Much of this research is based on registries built by high-volume surgeons and centers. These registries, often using modern outcome measures such as i-HOT, HAGOS and HOS are a stable ground upon which more quality research will be generated. Future research should adhere to these principles. For example, a paper in this edition is based on a national, high-compliance hip arthroscopy registry from Denmark, where all surgical centers are included [7]. The study identified predictors of outcome after FAI surgery and included over 2000 patients. Such high-quality registries ensure valid results in FAI research. It is important that studies are designed so that the quality of FAI research steadily improves so that the bar can be continually raised. The execution and publication of a number of randomised controlled trials on FAI surgery in recent years is evidence of this.

Several papers in this edition concern the effect of groin pain and FAI in athletes where FAIS is a major problem preventing participation. Although rates of return to sport (RTS) often are reported as high in studies, many patients still experience reduced load capacity. Defining RTS is challenging since FAIS is a condition that is load dependent. Returning to participation is not the same as full participation in both practice and games. The complexity of reporting RTS needs to be acknowledged and researchers should use sound methodology in reporting RTS [1].

Finally, the importance of rehabilitation, an often neglected topic, after hip injury is featured [6]. Perhaps more attention to rehabilitation will lead us to investigate how soft tissue and bony structures around the hip interact. Many papers often conclude with the statement, “future research is needed to clarify this topic”, rather than write that we continue encourage more high-quality research to shed light on what is perceived to be known and what is yet to be fully understood. There is, for example, still much to be done in the area of diagnostics and prevention in FAI research [5].