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 .
Mediolateral oversizing influences pain, function, and flexion after TKA
Purpose Manufacturers of total knee arthroplasty ( TKA )  have introduced narrower femurs to improve bone-implant fit . However , few studies have reported the clinical consequences of mediolateral oversizing . Our hypothesis was that component oversizing negatively influences the results after TKA . Methods One hundred and twelve prospect ively followed patients with 114 consecutive TKA ( 64 females and 50 males ) were retrospectively assessed . The mean age of the patients was 72 years ( range , 56 to 85 years ) . The dimensions of the femur and tibia were measured on a preoperative CT-scan and were compared with those of the implanted TKA . The influence of size variation on the clinical outcomes 1 year after surgery was assessed . Results Mediolateral overhang was observed in at least one area in 66 % of the femurs ( 84 % in females and 54 % in males ) and 61 % of the tibia ( 81 % in females and 40 % in males ) . Twenty-two patients presented no overhang in any area and 16 had overhang in all studied zones . The increase in the Pain and KOOS scores were 43 ± 21 and 36 ± 18 in the patients without overhang and 31 ± 19 and 25 ± 13 in patients with overhang ( p = 0.033 ; p = 0.032 ) . Knee flexion was 127 ° ± 7 and 121 ° ± 11 , respectively . Regression and latent class analysis showed a significant negative correlation between overall oversizing and overall outcome . Conclusions This study confirms that oversizing may lead to worse clinical results in TKA . The clinical consequences are that surgeons should pay attention not to oversize implants during implantation nd that oversizing should be ruled out in case of so called unexplained pain . Level of evidence IV
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 .