1. Division of Surgery & Interventional ScienceInstitute of Orthopaedic & Musculoskeletal ScienceUniversity College LondonRoyal National Orthopaedic HospitalStanmoreHA7 4LPUK
2. Department of OrthopaedicsSecond Affiliated Hospital of Fujian Medical UniversityQuanzhou362000People's Republic of China
3. State Key Laboratory of Solid LubricationLanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000People's Republic of China