A literature review of robotic systems showed that these systems can , similarly to computer navigation , reliably improve lower leg alignment , component positioning and soft tissues balancing .
Findings in this study suggest that computer navigation or robotic assistance may help managing these multiple variables and could improve outcomes .
Recently , there is a growing interest in surgical variables that are intraoperatively controlled by orthopaedic surgeons , including lower leg alignment , component positioning and soft tissues balancing .
Since more tight control over these factors is associated with improved outcomes of unicompartmental knee arthroplasty and total knee arthroplasty ( TKA ) , several computer navigation and robotic-assisted systems have been developed .
Although mechanical axis accuracy and component positioning have been shown to improve with computer navigation , no superiority in functional outcomes has yet been shown .
This could be explained by the fact that many differences exist between the number and type of surgical variables these systems control .
Most systems control lower leg alignment and component positioning , while some in addition control soft tissue balancing .
Finally , robotic-assisted systems have the additional advantage of improving surgical precision .
Manually controlling all these surgical variables can be difficult for the orthopaedic surgeon .
Comparison of Outcome and Survival After Unicompartmental Knee Arthroplasty Between Navigation and Conventional Techniques With an Average 9-Year Follow-Up.
BACKGROUND Unicompartmental knee arthroplasty(UKA ) has become a treatment of choice for many patients with isolated unicomparmental arthritis due to its specific advantages over total knee arthroplasty , but few studies have compared conventional and navigational UKA with similar instrumentation on mid- to long-term results . We investigated whether the use of imageless navigation can improve implant positioning and clinical outcomes of UKA at a long-term follow-up compared to the conventional technique . METHODS We prospect ively studied clinical and radiological results in 68 patients with an average age of 64.0 years ( range , 50 to 81 years ) who received UKA between January 2003 and December 2005 using the conventional or navigational technique .  Clinical evaluations were performed preoperatively and the last follow-up included knee range of motion , Hospital for Special Surgery ( HSS ) scores , Western Ontario and McMaster Universities Osteoarthritis Index ( WOMAC ) scores and Visual Analogue Scale ( VAS ) pain score . For radiologic evaluation , the mechanical alignment of the lower limb was measured using mechanical femoro-tibial angle ( mFTA ) and Kennedy protocol . RESULTS After an average 9-year follow-up ( range , 7.4 to 10.8 years ) , the navigation group showed better coronal alignments of the components , fewer radiological outliers and better clinical scores , but similar estimated 10-year prosthesis survival rates . CONCLUSION This study indicates that the use of navigation significantly contributes to the desired mechanical axis and improved component placement as compared to the conventional technique . LEVEL OF EVIDENCE Prospect i ve comparative study , Level III
A literature review of robotic systems showed that these systems can , similarly to computer navigation , reliably improve lower leg alignment , component positioning and soft tissues balancing .
Findings in this study suggest that computer navigation or robotic assistance may help managing these multiple variables and could improve outcomes .
Recently , there is a growing interest in surgical variables that are intraoperatively controlled by orthopaedic surgeons , including lower leg alignment , component positioning and soft tissues balancing .
Since more tight control over these factors is associated with improved outcomes of unicompartmental knee arthroplasty and total knee arthroplasty ( TKA ) , several computer navigation and robotic-assisted systems have been developed .
Although mechanical axis accuracy and component positioning have been shown to improve with computer navigation , no superiority in functional outcomes has yet been shown .
This could be explained by the fact that many differences exist between the number and type of surgical variables these systems control .
Most systems control lower leg alignment and component positioning , while some in addition control soft tissue balancing .
Finally , robotic-assisted systems have the additional advantage of improving surgical precision .
Manually controlling all these surgical variables can be difficult for the orthopaedic surgeon .