PMID- 29223778
OWN - NLM
STAT- MEDLINE
DCOM- 20190917
LR  - 20190917
IS  - 1877-0568 (Electronic)
IS  - 1877-0568 (Linking)
VI  - 104
IP  - 2
DP  - 2018 Apr
TI  - Differences in trochlear parameters between native and prosthetic kinematically 
      or mechanically aligned knees.
PG  - 165-170
LID - S1877-0568(17)30342-0 [pii]
LID - 10.1016/j.otsr.2017.10.009 [doi]
AB  - INTRODUCTION: Kinematic (KA) and mechanical (MA) alignment techniques are two 
      different philosophies of implant positioning that use the same TKA implants. 
      This might generate differences in the resulting prosthetic trochleae parameters 
      between the two techniques of alignment. Our study aim was to test the following 
      hypotheses : (1) mechanically or kinematically aligned femoral implant 
      understuffs the native trochlear articular surface and poorly restores the native 
      groove orientation, and (2) the orientation of the prosthetic trochlear groove 
      and trochlear fill are different between MA and KA. METHODS: Three-dimensional 
      models of the femur were made from segmentation of preoperative Magnetic 
      Resonance Imaging scans (MRIs) of ten subjects with isolated medial tibiofemoral 
      osteoarthritis. In-house planning and analysis software kinematically and 
      mechanically aligned a modern cruciate retaining femoral component and determined 
      differences in parameters of the trochlear fit between native and prosthetic 
      trochleae, and between KA and MA prosthetic trochleae. RESULTS: The MA prosthetic 
      trochleae did not fill (understuffed) the entire length of the native medial 
      facet and the proximal 70% of the native groove and lateral facet, and oriented 
      the trochleae groove 8 degrees  more valgus than native. The KA prosthetic trochleae 
      understuffed the proximal 70% of the native trochleae, and had a groove 6 degrees  more 
      valgus than native. The KA trochleae understuffed the medial facet distally and 
      oriented the groove 2 degrees  less valgus and 3 degrees  more internally rotated than the MA 
      trochleae. CONCLUSION: MA and KA prosthetic trochleae substantially understuff 
      and create a prosthetic groove more valgus compared to native trochlear anatomy, 
      and they also differed between each other regarding trochleae stuffing and groove 
      alignment. Although randomized trials have not shown differences in 
      patellofemoral complications between KA and MA, a femoral component designed 
      specifically for KA that more closely restores the native trochlear anatomy might 
      improve patient reported satisfaction and function. LEVEL OF EVIDENCE: Level 2 
      controlled laboratory study.
CI  - Copyright (c) 2017 Elsevier Masson SAS. All rights reserved.
FAU - Riviere, C
AU  - Riviere C
AD  - MSK Lab, Charing Cross Hospital, Imperial College London, W6 8RP London, UK. 
      Electronic address: rivierech@gmail.com.
FAU - Iranpour, F
AU  - Iranpour F
AD  - MSK Lab, Charing Cross Hospital, Imperial College London, W6 8RP London, UK.
FAU - Harris, S
AU  - Harris S
AD  - MSK Lab, Charing Cross Hospital, Imperial College London, W6 8RP London, UK.
FAU - Auvinet, E
AU  - Auvinet E
AD  - MSK Lab, Charing Cross Hospital, Imperial College London, W6 8RP London, UK.
FAU - Aframian, A
AU  - Aframian A
AD  - MSK Lab, Charing Cross Hospital, Imperial College London, W6 8RP London, UK.
FAU - Parratte, S
AU  - Parratte S
AD  - Service de chirurgie orthopedique, hopital Sainte-Marguerite, universite 
      Aix-Marseille, 13009 Marseille, France.
FAU - Cobb, J
AU  - Cobb J
AD  - MSK Lab, Charing Cross Hospital, Imperial College London, W6 8RP London, UK.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20171206
PL  - France
TA  - Orthop Traumatol Surg Res
JT  - Orthopaedics & traumatology, surgery & research : OTSR
JID - 101494830
SB  - IM
MH  - *Arthroplasty, Replacement, Knee/methods
MH  - Biomechanical Phenomena
MH  - Female
MH  - Femur
MH  - Humans
MH  - Imaging, Three-Dimensional
MH  - Knee Joint/*physiopathology/surgery
MH  - *Knee Prosthesis
MH  - Magnetic Resonance Imaging
MH  - Middle Aged
MH  - Osteoarthritis, Knee/*diagnostic imaging/*surgery
OTO - NOTNLM
OT  - Kinematic alignment
OT  - Stuffing
OT  - Total knee arthroplasty
OT  - Trochleae
EDAT- 2017/12/11 06:00
MHDA- 2019/09/19 06:00
CRDT- 2017/12/11 06:00
PHST- 2017/06/13 00:00 [received]
PHST- 2017/10/17 00:00 [revised]
PHST- 2017/10/27 00:00 [accepted]
PHST- 2017/12/11 06:00 [pubmed]
PHST- 2019/09/19 06:00 [medline]
PHST- 2017/12/11 06:00 [entrez]
AID - S1877-0568(17)30342-0 [pii]
AID - 10.1016/j.otsr.2017.10.009 [doi]
PST - ppublish
SO  - Orthop Traumatol Surg Res. 2018 Apr;104(2):165-170. doi: 
      10.1016/j.otsr.2017.10.009. Epub 2017 Dec 6.