“More accurate correction using “patient-specific” cutting guides in opening wedge distal femur varization osteotomies
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The distal femoral varization osteotomy (DFVO) by a lateral opening wedge osteotomy is an established intervention for patients suffering from lateral femoro-tibial osteoarthritis on a genu valgum deformity. In order to improve the accuracy of this correction, the use of a customized cutting guide (PSI) has been proposed as an alternative to conventional technique. The objective of our study was to compare the accuracy of post-operative alignment following DFVO in the coronal and sagittal plane using either a conventional abacus technique or PSI guide.
Twenty-one patients that underwent lateral opening wedge osteotomy from a technique using PSI based on 3D CT-scans were matched 1:1 to 21 patients operated on using a conventional technique (pre-operative planning performed on standard radiographs). The accuracy of the correction was analyzed, comparing coronal and sagittal mechanical post-operative angles with pre-operative planning.
With regard to alignment in the coronal plane (HKA correction), our study demonstrated a significant improvement in the accuracy of the correction obtained in the PSI group compared to the conventional group (0.43 ± 0.50 vs 3.95 ± 1.64 p < 0.001). In the sagittal plane (PDFA correction), we also found a significant improvement in correction accuracy in the PSI group (0.52 ± 0.60 vs 3.10 ± 1.83 p < 0.001).
There was a significant decrease in operating time (delta 7.7 ± 3.07 (1.5–13.9) (p = 0.0.161) and fluoroscopic images taken (6.9 ± 0.54 (5.8–8) p < 0.001).
Our results suggest that the use of PSI in DFVO improves the accuracy of correction in both the coronal and sagittal planes compared to conventional techniques.
KeywordsFemoral Osteotomy External-opening Accuracy Customized Cutting-guide
Distal femoral varization osteotomy
High tibial osteotomy
Hip knee angle (coronal alignment of the limb)
Posterior distal femoral angle (sagittal alignment of the femur)
International Knee Society Score with a Global evaluation (IKSG) and Function evaluation (IKSF)
Author contributions statement
MO and SP designed the protocol.
MO and CJ performed database analysis.
CJ, MO, and AS wrote the initial draft.
MO, SP, and JNA edited the different version of the draft.
CJ, MO, SP, AS, and JNA approved of the submitted and final versions.
Compliance with ethical standards
Conflict of interest
MO is educational consultant for New-Clip, Stryker and Arthrex.
SP is educational consultant for New-Clip, Zimmer and Arthrex.
JNA receives royalties from Zimmer.
CJ and AS have nothing to disclose.
- 6.Paley D, Herzenberg JE, Tetsworth K et al (1994) Deformity planning for frontal and sagittal plane corrective osteotomies. Orthop Clin N Am 25:425–465Google Scholar