The medially spherical GMK Sphere (Medacta International AG, Castel San Pietro, Switzerland) total knee arthroplasty (TKA) was previously shown to accommodate lateral rollback while pivoting around a stable medial compartment, aiming to replicate native knee kinematics in which some coronal laxity, especially laterally, is also present. We assess coronal plane kinematics of the GMK Sphere and explore the occurrence and pattern of articular separation during static and dynamic activities. Using pulsed fluoroscopy and image matching, the coronal kinematics and articular surface separation of 16 well-functioning TKAs were studied during weight-bearing and non-weight-bearing, static, and dynamic activities. The closest distances between the modelled articular surfaces were examined with respect to knee position, and proportions of joint poses exhibiting separation were computed.Objectives
Methods
Our study aimed to examine if a mobile-bearing total knee replacement
(TKR) offered an advantage over fixed-bearing designs with respect
to rates of secondary resurfacing of the patella in knees in which
it was initially left unresurfaced. We examined the 11-year report of the New Zealand Joint Registry
and identified all primary TKR designs that had been implanted in
>
500 knees without primary resurfacing of the patella. We examined
how many of these were mobile-bearing, fixed-bearing cruciate-retaining
and fixed-bearing posterior-stabilised designs. We assessed the rates
of secondary resurfacing of the patella for each group and constructed
Kaplan-Meier survival curves.Objectives
Methods
