The effect of the native kinematics of the knee on the outcome following total knee arthroplasty.
OBJECTIVE
The aim of this study was to investigate differences in pain, range of movement function and satisfaction at three months and one year after total knee arthroplasty (TKA) in patients with an oblique pattern of kinematic graph of the knee and those with a varus pattern.


METHODS
A total of 91 patients who underwent TKA were included in this retrospective study. Patients (59 women and 32 men with mean age of 68.7 years; 38.6 to 88.4) were grouped according to kinematic graphs which were generated during navigated TKA and the outcomes between the groups were compared.


RESULTS
The graphs were varus in 50 patients (55%), oblique in 19 (21%), neutral in 17 (18.5%) and valgus in five (5.5%). After adjustment for pre-operative scores and gender, compared with patients with varus knee kinematics, patients with an oblique kinematic graph had a poorer outcome with lower Knee Society scores at three months (9.2 points, p = 0.038).


CONCLUSIONS
We found four distinct kinematic graphs in knees and that patients with an oblique graph have a poorer outcome in the short-term after TKA. Cite this article: Bone Joint J 2016;98-B:1471-8.
Royal Perth Hospital, Wellington St, Perth, WA, 6000, Australia.
L T
LT
Mooney
Curtin University, GPO Box 1987, Perth, WA 6845, Australia.
A
A
Smith
Royal Perth Hospital, Wellington St, Perth, WA, 6000, Australia.
K
K
Sloan
Saint John of God Hospital, Subiaco, Australia.
G W
GW
Clark
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods / Q000534:rehabilitation*; D001696:Biomechanical Phenomena; D017760:Bone Malalignment / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000534:rehabilitation*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007430:Intraoperative Care / Q000379:methods; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010149:Postoperative Pain / Q000209:etiology; D017060:Patient Satisfaction; D011379:Prognosis; D016059:Range of Motion, Articular; D020127:Recovery of Function; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted / Q000379:methods / Q000534:rehabilitation; D016896:Treatment Outcome
Alignment; Arthroplasty; Kinematics; Knee; Replacement