Although there was a significant reduction of the duration of surgery in both patient-specific instrumentation groups in comparison to conventional instrumentation ( MRI versus conventional , @ minutes -LSB- range , @-@ minutes -RSB- versus @ minutes -LSB- range , @-@ minutes -RSB- , p < @ ; CT versus conventional , @ minutes -LSB- range , @-@ minutes -RSB- versus @ minutes -LSB- range , @-@ minutes -RSB- , p < @ ) , there were no differences in the postoperative Knee Society pain and function and WOMAC scores among the groups .