Evaluation of patellofemoral joint in ADVANCE Medial-pivot total knee arthroplasty.
OBJECTIVE
ADVANCE Medial Pivot (MP) (Wright Medical) total knee arthroplasty (TKA) was established to replicate normal tibio-femoral knee joint kinematics, however, its influence on the patello-femoral (PF) joint is unclear. The purpose in this study was to assess the PF joint conditions in Advance MP TKA, via radiography and three-dimensional image-matching software.


METHODS
Ten subjects with osteoarthritis were treated with the ADVANCE MP TKA. Pre-operatively and one month after surgery, skyline views at 30, 60, and 90° of flexion were taken, and patella shift and tilt were measured. With 2D-3D registration techniques using software, implant orientations were matched with the pre-operative CT and changes in the anterior part of the femoral prosthesis, condylar twist angle (CTA) for femoral rotation, and tibial rotation were evaluated. The relationships between morphological and rotational changes were evaluated.


RESULTS
There were significant differences in patella tilt at 60° and patella shift at all angles between pre- and post-operation (p < 0.05). No correlation was found between morphological changes in the anterior femur with patella tilt and shift. A positive correlation between postoperative CTA and patella shift at 90° was found (p < 0.05); however, no correlation was found between rotational alignment of the tibial component and patella tilt and shift.


CONCLUSIONS
ADVANCE MP TKA changed patello-femoral joint kinematics, compared to that found before surgery. The kinematic features were mainly due to the design concepts for tibio-femoral joint motion, indicating the difficulty to reproduce normal patello-femoral joint kinematics after TKA.
Department of Orthopaedic Surgery, Hyogo Rehabilitation Center Hospital, 1070 Akebono-cho, Nishi-ku, Kobe, 651-2181, Japan.
Nobuaki
N
Chinzei
Kazunari
K
Ishida
Tomoyuki
T
Matsumoto
Yuichi
Y
Kuroda
Atsushi
A
Kitagawa
Ryosuke
R
Kuroda
Toshihiro
T
Akisue
Kotaro
K
Nishida
Masahiro
M
Kurosaka
Nobuhiro
N
Tsumura
D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation / Q000379:methods*; D001696:Biomechanical Phenomena; D005260:Female; D005269:Femur / Q000601:surgery; D006801:Humans; D021621:Imaging, Three-Dimensional; D007719:Knee Joint / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D020370:Osteoarthritis, Knee / Q000601:surgery*; D010329:Patella / Q000601:surgery; D057071:Patellofemoral Joint / Q000000981:diagnostic imaging* / Q000502:physiology* / Q000601:surgery; D011474:Prosthesis Design; D016059:Range of Motion, Articular / Q000502:physiology*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome