Tibesku 2011.

Methods	RCT stated Randomisation based on computer‐generated list Duration of study: 2 years
Participants	Inclusion: 50‐80 years, unilateral primary osteoarthritis, absence of mediolateral instability, deviation of the long leg axis of less than 10° Exclusion: any co‐morbidity that negatively influenced gait Germany: 33 participants Fixed: n = 17, 12 female, age 66 (± 10) years Mobile: n = 16, 9 female, age 65 (± 9) years
Interventions	Fixed: Genesis II (Smith and Nephew) Mobile: Genesis II, meniscal bearing (Smith and Nephew) No patellar resurfacing Cementing unclear
Outcomes	Flexion, KSS, HSS, SF‐36, Tegner, UCLA, VAS pain, gait analysis Assessments preoperative and at final follow‐up 24 months postoperative Average and standard deviation given
Notes	No funding stated No declarations of interest reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated list
Allocation concealment (selection bias)	Unclear risk	Not described
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Participant blinded
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Observer blinded
Incomplete outcome data (attrition bias) All outcomes	High risk	No description of withdrawals and dropouts; no intention‐to‐treat analysis
Selective reporting (reporting bias)	Unclear risk	No protocol available
Other bias	High risk	No homogeneity in participant groups on prognostic factors; no subgroups given that are homogeneous; co‐interventions not described in sufficient detail