Original Articles
The effect of surgeon experience on component positioning in 673 press fit condylar posterior cruciate-sacrificing total knee arthroplasties*,**

https://doi.org/10.1054/arth.2001.23569Get rights and content

Abstract

Abstract: Component angles of 673 Press Fit Condylar (PFC) total knee arthroplasties were measured from standard short-leg radiographs. The femoral and tibial resections were performed with intramedullary and extramedullary instrumentation. The mean coronal tibial component angle was 88.59° (SD, 2.28°; range, 78-98°), with 17.1% having values <87° and 1.9% having values >93°. The mean coronal femoral component angle was 97.43° (SD, 3.44°; range, 84-115°), with 9.1% having values <94° and 13.1% having values >100°. An ideal tibiofemoral angle of 4° to 10° of valgus was achieved in 75.3% of patients, being <4° in 18.6% and >10° in 6.1%. Alignment was not significantly different between consultant and trainee surgeons. Although varus positioning of the tibial component was the commonest error, the wide range of femoral component angles signifies problems with standard intramedullary femoral guides.

Section snippets

Materials and methods

Data are collected prospectively on all patients undergoing TKA at Princess Alexandra Hospital (PAH) for an ongoing research project. As part of this project, the component alignment of 673 posterior cruciate-sacrificing TKAs performed between January 1994 and December 1999 was measured. Radiographs were taken in a standard manner. The weight-bearing anteroposterior view was acquired using an 18 × 43 cm film and the knee in full extension, whereas the supine lateral view was taken using an 18 ×

Results

Radiographs of 673 implants were measured from 516 patients, of whom 157 had undergone simultaneous or staged bilateral TKAs. Surgery was performed by a consultant in 203 knees and by a trainee in 409 knees; the grade of surgeon was unknown in the remaining 61 knees, and these were excluded from the comparative analysis. Component alignment data are summarized in Table 1 and Fig. 3.

. Component Alignment of 673 Posterior Cruciate-Sacrificing Total Knee Arthroplasties

Empty CellMeanSDModeMedianRange
Coronal

Discussion

Component position plays a fundamental role in the function of a TKA by determining the alignment of the knee and patellofemoral tracking. It has been shown previously that malpositioned TKAs have higher rates of failure 1, 2, 7 and are associated with radiolucent lines around the patellar component [8]. This study has shown that the combination of intramedullary femoral and extramedullary tibial cutting guides produced satisfactory component positioning in most knees. It is a concern, however,

References (36)

  • MH Oswald et al.

    Radiological analysis of normal axial alignment of femur and tibia in view of total knee arthroplasty

    J Arthroplasty

    (1993)
  • MA Ritter et al.

    Postoperative alignment of total knee replacement: its effect on survival

    Clin Orthop

    (1994)
  • JH Bargren et al.

    Alignment in total knee arthroplasty: correlated biomechanical and clinical observations

    Clin Orthop

    (1983)
  • M Tew et al.

    Tibiofemoral alignment and the results of knee replacement

    J Bone Joint Surg Br

    (1985)
  • JN Insall et al.

    Total knee arthroplasty

    Clin Orthop

    (1985)
  • GR Scuderi et al.

    The posterior stabilized knee prosthesis

    Orthop Clin North Am

    (1989)
  • F: Ewald

    The Knee Society total knee arthroplasty roentgenographic evaluation and scoring system

    Clin Orthop

    (1989)
  • RS Jeffery et al.

    Coronal alignment after total knee replacement

    J Bone Joint Surg Br

    (1991)
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    *

    Funds were received in support of the research described in this article from Johnson & Johnson.

    **

    Reprint requests: M. J. K. Bankes, 18 Howard Walk, London N2 OHB, U.K. E-mail: [email protected]

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