Anterior hip pain in young adult (20 to 50) has two main causes: secondary osteo-arthritis on development dysplasia of the hip, and femoro-acetabular impigement (FAI). This symposium had two parts: the first one analyses long-term results of non-prosthetic surgery (283 osteotomies and shelfs at 15 years FU). The second part concerned the different syndromes with acute anterior hip pain, especially due to FAI and to labral tears.In hip dysplasia, 56 shelf operations, 100 proximal femoral varus osteotomies associated or not with a shelf arthroplasty,and 127 Chiari osteotomies were examined with 10 years minimum follow-up. Only 15% of patients were lost at follow-up before 10 years and average follow-up was 15 years. Results were considered as satisfactory when the Merle d'Aubigne rating was 15/18 or more. The 3 main factors of good prognosis were: a complete correction of both femoral and acetabular dysplasia; age at operation under 40; a moderate arthritis (grade I or II according to De Mourgues and Patte). In single acetabular dysplasia with 3 favorable prognosis factors(no coxa valga, age under 40, arthritis 1 or 2), 85% good results were achieved at 15 years. When patients were over 40 at operation, or in arthritis grade over 2, only 55% of good results were observed. Varus osteotomies, associated or not with shelf arthroplasties, achieved also 85% goods results at 15 years when the 3 favorable prognosis factors were present. Similar good results were also obtained by Chiari osteotomy, but this operation was associated with 12% complications, and more that 25% of lasting limping. Therefore, with 85% good results at 15 years (and often over 20 years), non prosthetic surgery performed at 30-35 years, achieved better functional results than total hip arthroplasty, longer lasting, and not jeopardizing any further possibility of prosthetic surgery.As concerns acute anterior pain of the hip, the clinical and imaging patterns of the different syndromes have been precised: femoro-acetabular impigement by cam (or by pincer), labral tears in hip dysplasia. There were distinguished from the other secondary impigements, for example by acetabular malposition due to pelvis anteflexion or by other hip diseases: overuse arthritis, coxa retrorsa, etc. Several examples of typical syndromes were presented to support the recommended imaging techniques. The results of the speakers with different surgical treatments were reported as well as concerns open surgery than arthroscopic treatment (60 cases).