Abstract
Objectives:
Patient specific instrumentation (PSI) represents a promising tool to improve the accuracy and predictability of osteotomy around the knee, and is also of value when combining with associated procedures to avoid convergence. There are a growing number of PSI options available for osteotomy. The present study aims to assess the accuracy of correction of alignment in patients undergoing osteotomy procedures using “Personalised Surgery (PS)” PSI instrumentation by non-designer surgeons across Western Australia.
Methods:
18 patients operated by 6 different surgeons in 6 different institutions in Western Australia were included. Patients completed EOS scanning preoperatively at median 1-month preoperatively, underwent planning using the PS CT based software and underwent surgery using the PS instrumentation. All patients underwent post operative EOS scanning at the same institution using the same protocol at median 2.5 months post operatively.
Results:
12 Patients had isolated osteotomies, and 6 had combined procedures (with Revision ACL +/- Mosaicplasty). 11 patients underwent medial opening wedge (MOW) high tibial osteotomy (HTO), of which 4 of these had combined revision anterior cruciate ligament (ACL) reconstruction as part of the same procedure. 6 patients underwent medial closing wedge (MCW) distal femoral osteotomy (DFO), of which 2 underwent LFC Mosaicplasty. One patient underwent lateral opening wedge (LOW) DFO. One patient in the MOW HTO group had collapse of their osteotomy with delayed union at 6 months follow-up and was excluded. Accurate tunnel placement was achieved in combined ACL cases. The median planned change in Hip-knee-angle (HKA) was 5.45 degrees (n=18, range 2.63 to 13.64, SD 3.74). The median deviance from the planned HKA correction measured on post operative EOS was 0.79 degrees (n=17, range 0.1 to 4.4 degrees, SD 3.6). The median planned change in PTS was 0.5 degrees (n=11, range 0 to 7.15, SD 4.0). The median deviance from planned PTS was 0.5 degrees (n=11, range 0-4.34, SD 1.5).
Conclusion:
Real world use of Personalised Surgery PSI instrumentation in this non-designer series showed predictable and accurate correction of coronal alignment for both isolated and combined knee osteotomy.