Robotic-assisted total knee arthroplasty in post-traumatic and previously operated knees with retained hardware:...

Total knee arthroplasty (TKA) after periarticular fracture fixation, malunion, high tibial osteotomy, or other previous knee surgery differs substantially from routine primary TKA. Retained implants, extra-articular deformity, distorted landmarks, bone defects, scarred soft tissues, and infection risk may all compromise standard instrumentation and implant positioning. Robotic-assisted TKA (RA-TKA) is increasingly used in selected non-standard primary cases because computed tomography -based or imageless planning can define deformity, anticipate implant-hardware conflicts, guide bone resection, and quantify gap balance. However, the available evidence remains limited and heterogeneous, consisting mainly of case reports, small case series, and early retrospective comparative cohorts. This scoping review synthesizes clinical evidence on RA-TKA in post-traumatic and previously operated knees with retained or recently removed hardware. It also integrates relevant navigation and hardware-removal literature to propose a practical workflow for patient selection, imaging, hardware strategy, robotic execution, implant escalation, intraoperative safety checks, and implementation. Current literature supports technical feasibility and suggests potential workflow advantages in carefully selected cases, particularly when landmarks are unreliable, intramedullary instrumentation is blocked, or three-dimensional planning may clarify implant-hardware conflict. These findings should not be interpreted as evidence of proven superiority. Comparative evidence remains sparse, and follow-up is short. Current data do not establish improved survivorship, lower infection risk, better patient-reported outcomes, or cost-effectiveness. RA-TKA should therefore be framed as a planning and execution adjunct, not as a stand-alone solution for complex conversion-style primary TKA.