The purpose of this study is to investigate whether patients undergoing surgical treatment (hip arthroscopy) of FAI syndrome will positively benefit from capsular closure, in terms of higher scores in validated patient reported outcome measurements, compared to a Group of patients with FAI syndrome where the capsule is left open at the end of the surgical procedure.

Inclusion Criteria:

• Radiological and symptomatic Femoroacetabular Impingement, where surgery is indicated. Preoperatively a minimum of 3 months of relevant physiotherapeutic treatment should have been performed.

Exclusion Criteria:

• Previous hip surgery in either hip
• Malignant disease
• Recent hip or pelvic fractures
• Arthritic disease
• Hip joint dysplasia
• Legg-Calvé-Perthes
• Slipped Capital Femoris Epiphysis
• Recent (within 6 weeks) medical treatment with corticosteroids
• Language problems of any kind