Image-based robotic total knee arthroplasty preserves the knee joint line level even in advanced fixed flexion deformities when combined with functional alignment principles: A retrospective comparative cohort study.
Giacomo Pacchiarotti, Alessandro Todesca, George Mihai Avram, Giovanni Longo, Domenico Paolicelli, Stefano Gumina
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引用次数: 0
Abstract
Purpose: Fixed flexion deformity (FFD) is traditionally addressed in total knee arthroplasty (TKA) with extensive soft tissue release and distal femoral recut, which increases bone stock consumption and raises the knee joint line (JL). This study aimed to evaluate differences in the anatomical restoration of the JL and bone stock preservation between FFD knees and a control group during robotic-assisted (RA) TKA combined with functional alignment (FA).
Methods: A retrospective comparative cohort study examined 120 knees undergoing RA TKA. The knees were categorised into two groups: the study group, with FFD > 5°, and the control group, without FFD. Further analysis stratified the study group based on the severity of the deformity: mild (5-9°), intermediate (10-14°) and advanced (>15°). The Mann-Whitney U test was utilised to investigate the differences between the control and study groups.
Results: The study group comprised 64 knees, presenting an average flexion contracture and range of motion (ROM) of 11.3 ± 4.7° and 112.7 ± 11.6°, respectively. The control group comprised 56 knees, with an extension deficit and ROM of 1.6 ± 2.1° and 123.5 ± 8.3°, respectively. The JL was proximally displaced on average by 0.1 ± 1.2 mm in the study group and lowered by 0.7 ± 0.9 mm in the control group. Analysis of JL in the subgroups showed a lowering of 0.3 ± 1.2 mm in the mild deformity subgroup and a rise of 0.08 ± 1.3 mm and 0.8 ± 0.8 mm in the intermediate and advanced FFD subgroups, respectively, showing no statistical significance. The combined thickness of tibial proximal and femoral distal bone cuts measured 12.3 ± 1.6 mm in the study group and 11.4 ± 1.4 mm in the control group.
Conclusions: FA in RA-assisted TKA can correct FFD, minimising bone cuts while preserving anatomical JL level.
期刊介绍:
Few other areas of orthopedic surgery and traumatology have undergone such a dramatic evolution in the last 10 years as knee surgery, arthroscopy and sports traumatology. Ranked among the top 33% of journals in both Orthopedics and Sports Sciences, the goal of this European journal is to publish papers about innovative knee surgery, sports trauma surgery and arthroscopy. Each issue features a series of peer-reviewed articles that deal with diagnosis and management and with basic research. Each issue also contains at least one review article about an important clinical problem. Case presentations or short notes about technical innovations are also accepted for publication.
The articles cover all aspects of knee surgery and all types of sports trauma; in addition, epidemiology, diagnosis, treatment and prevention, and all types of arthroscopy (not only the knee but also the shoulder, elbow, wrist, hip, ankle, etc.) are addressed. Articles on new diagnostic techniques such as MRI and ultrasound and high-quality articles about the biomechanics of joints, muscles and tendons are included. Although this is largely a clinical journal, it is also open to basic research with clinical relevance.
Because the journal is supported by a distinguished European Editorial Board, assisted by an international Advisory Board, you can be assured that the journal maintains the highest standards.
Official Clinical Journal of the European Society of Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA).