Footnotes

• Twitter @GilbertMoatshe, @larsengebretsen

• Contributors All authors (GM, CK, AG and LE) have contributed substantially to this work and meet the ICMJE criteria. They have all made substantial contributions to the conception of the work; drafting the work or revising it critically for important intellectual content; final approval of the version to be published and agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

• Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

• Competing interests GM: editorial board—Journal of Arthroscopy. Committee Member—ISAKOSLE: Acta Orthopaedica: Editorial or governing board, American Orthopaedic Society for Sports Medicine: Board or committee member. Arthrex: IP royalties; paid consultant; research support. Biomet: research support. BJSM: publishing royalties, financial or material support. ESSKA: board or committee member. iBalance: stock or stock options. International Society of Arthroscopy, Knee Surgery, and Orthopaedic Sports Medicine: board or committee member. Journal of Bone and Joint Surgery—American: editorial or governing board. Knee: editorial or governing board. Knee Surgery, sports traumatology, arthroscopy: editorial or governing board. Smith and Nephew: research support.

• Provenance and peer review Commissioned; externally peer reviewed.