[1] Univ Groningen, Univ Med Ctr Groningen, Dept Plast Surg, Groningen, Netherlands
[2] Univ Groningen, Univ Med Ctr Groningen, Dept Gen Practice & Elderly Care Med, Acad Gen Practitioner Dev Network, Groningen, Netherlands
[3] Univ Oxford, Nuffield Dept Orthopaed Rheumatol & Musculoskelet, Botnar Res Ctr, Oxford, England
[4] Univ Oxford, Oxford Univ Hosp NHS Fdn Trust, John Radcliffe Hosp, Dept Plast & Reconstruct Surg, Oxford, England
[5] Eindhoven Univ Technol, Dept Math & Comp Sci, Eindhoven, Netherlands
[6] Univ Med Ctr Groningen, Dept Plast Surg, HPC BB81,POB 30-001, NL-9700RB Groningen, Netherlands