title: Lateral versus medial tibial plateau: morphometric analysis and adaptability with current tibial component design.
abstract: The purpose of this study was to analyze the in vivo dimensions of each tibial plateau for planning of unicompartmental knee arthroplasty (UKA), and to compare the morphometric data to the dimensions of nine current designs of UKA tibial components. Thirty-seven knees (31 females and 6 males) operated on with UKA were studied. All patients were examined postoperatively using computed tomography (CT). There were 18 lateral and 19 medial UKAs. On the CT scan, each operated tibial plateau was measured in the transverse plane at the resection level, just below the full polyethylene tibial component. We measured the length of the anteroposterior (AP) cut as well as the maximal mediolateral dimension of the resected plateau (perpendicular to the AP cut). We compared the measurements with nine current UKA systems: Accuris (Smith and Nephew), Advance (Wright Medical), HLS Uni Evolution (Tornier), Miller-Galante and "ZUK" (Zimmer), Oxford and Oxford alpha (Biomet), Preservation (DePuy) and Unix (Stryker). There was good correlation between patient height and mediolateral dimension (r=0.6), and between patient height and area of total tibial plateau (r=0.7). The anteroposterior dimension was greater for the medial plateau (mean 50.8 mm, SD 3.3) than for the lateral plateau (mean 47.2 mm, SD 3.3). This difference was statistically significant (P=0.0016). Some UKA implants are designed with an asymmetric femoral component, but none have an asymmetric tibial component. The present study suggests, however, that the shape of the medial tibial plateau differs from that of the lateral plateau. This difference can lead to mediolateral overhang for medial UKA, if the surgeon aims for optimal anteroposterior coverage.
authors.affiliation: Department of Orthopaedic Surgery, Centre Albert-Trillat, Hopital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, France. elvire.servien@chu-lyon.fr
authors.forename: E
authors.initials: E
authors.lastname: Servien
authors.forename: M
authors.initials: M
authors.lastname: Saffarini
authors.forename: S
authors.initials: S
authors.lastname: Lustig
authors.forename: S
authors.initials: S
authors.lastname: Chomel
authors.forename: Ph
authors.initials: P
authors.lastname: Neyret
mesh_terms: D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation* / Q000379:methods*; D004867:Equipment Design; D005260:Female; D006801:Humans; D007720:Knee Prosthesis / Q000009:adverse effects*; D008297:Male; D013977:Tibia / Q000033:anatomy & histology* / Q000601:surgery
references.citation: J Arthroplasty. 2000 Dec;15(8):982-9
references.pmid: 11112191
references.citation: Knee. 2006 Mar;13(2):122-6
references.pmid: 16403637
references.citation: Arthroscopy. 2007 May;23(5):503-8
references.pmid: 17478281
references.citation: J Orthop Res. 1989;7(1):132-7
references.pmid: 2908904
references.citation: J Arthroplasty. 2003 Sep;18(6):780-3
references.pmid: 14513454
references.citation: Knee. 2007 Mar;14(2):138-44
references.pmid: 17188876
references.citation: J Bone Joint Surg Br. 2001 Mar;83(2):191-4
references.pmid: 11284563
references.citation: Clin Orthop Relat Res. 1994 Feb;(299):81-5
references.pmid: 8119041
references.citation: Knee Surg Sports Traumatol Arthrosc. 1997;5(4):251-7
references.pmid: 9430576
references.citation: Knee. 2007 Aug;14(4):295-300
references.pmid: 17600719
references.citation: J Arthroplasty. 2002 Dec;17(8):1028-32
references.pmid: 12478514
references.citation: Knee Surg Sports Traumatol Arthrosc. 2007 Apr;15(4):436-42
references.pmid: 16964513
references.citation: J Bone Joint Surg Am. 2003;85-A Suppl 4:115-22
references.pmid: 14652402
references.citation: Clin Orthop Relat Res. 2001 Nov;(392):272-8
references.pmid: 11716395
references.citation: J Arthroplasty. 1995 Feb;10(1):47-51
references.pmid: 7730830
references.citation: Knee Surg Sports Traumatol Arthrosc. 2004 Mar;12(2):130-5
references.pmid: 12756521
references.citation: Clin Orthop Relat Res. 2001 Nov;(392):279-82
references.pmid: 11716396
references.citation: J Bone Joint Surg Br. 2002 Jul;84(5):653-7
references.pmid: 12188479
references.citation: J Bone Joint Surg Br. 1998 Nov;80(6):983-9
references.pmid: 9853489