Background: As advanced technology continues to evolve, incorporating robotics into surgical procedures has become imperative for precision and accuracy in preoperative planning. Nevertheless, the integration of three-dimensional (3D) imaging into these processes presents both financial considerations and potential patient safety concerns. This study aims to assess the accuracy of a novel 2D-to-3D knee reconstruction solution, RSIP XPlan.ai™ (RSIP Vision, Jerusalem, Israel), on preoperative total knee arthroplasty (TKA) patient anatomies. Methods: Accuracy was calculated by measuring the Root Mean Square Error (RMSE) between X-ray-based 3D bone models generated by the algorithm and corresponding CT bone segmentations (distances of each mesh vertex to the closest vertex in the second mesh). The RMSE was computed globally for each bone, locally for eight clinically relevant bony landmark regions, and along simulated bone cut contours. In addition, the accuracies of three anatomical axes were assessed by comparing angular deviations to inter- and intra-observer baseline values. Results: The global RMSE was 0.93 ± 0.25 mm for the femur and 0.88 ± 0.14 mm for the tibia. Local RMSE values for bony landmark regions were 0.51 ± 0.33 mm for the five femoral landmarks and 0.47 ± 0.17 mm for the three tibial landmarks. The RMSE along simulated cut contours was 0.75 ± 0.35 mm for the distal femur cut and 0.63 ± 0.27 mm for the proximal tibial cut. Anatomical axial average angular deviations were 1.89° for the trans epicondylar axis (with an inter- and intra-observer baseline of 1.43°), 1.78° for the posterior condylar axis (with a baseline of 1.71°), and 2.82° (with a baseline of 2.56°) for the medial–lateral transverse axis. Conclusions: The study findings demonstrate promising results regarding the accuracy of XPlan.ai™ in reconstructing 3D bone models from plain-film X-rays. The observed accuracy on real-world TKA patient anatomies in anatomically relevant regions, including bony landmarks, cut contours, and axes, suggests the potential utility of this method in various clinical scenarios. Further validation studies on larger cohorts are warranted to fully assess the reliability and generalizability of our results. Nonetheless, our findings lay the groundwork for potential advancements in future robotic arthroplasty technologies, with XPlan.ai™ offering a promising alternative to conventional CT scans in certain clinical contexts.

Background: The management of bone defects remains one of the major challenges surgeons are faced with in revision total knee arthroplasty (RTKA). Large and uncontained bone defects are traditionally managed with metaphyseal sleeves that facilitate osseointegration and have reported construct stability. While many studies have presented excellent short-term outcomes using metaphyseal sleeves, less is known on their performance in the longer term. The purpose of this study was to present our mid-term results of the metaphyseal sleeves used in patients undergoing RTKA.Materials and methods: Between January 2007 and January 2015, 30 patients underwent RTKA with the use of a CCKMB prosthesis combined with an osteointegrative sleeve. The main indications for RTKA were instability in 40% of the cases (n = 12), aseptic loosening in 30% (n = 9), infection in 26.7% (n = 8), and “other” in 3.3% (n = 1). The minimal follow-up time was 5 years and the mean follow-up time was 82.4 months (SD = 22.6). Clinical outcomes were assessed by Knee Society scores (KSS), range of motion and rate of re-operation.Results: The mean Knee Society score increased significantly from 72.1 preoperatively to 90.0 postoperatively (p < 0.001). The cumulative incidence of re-operation in our study was 13.3% (n = 4). Our study reported no cases of aseptic loosening or mobile-bearing spin-out. Knee flexion to 90° and more was impossible in seven cases (23.3%) preoperatively and in one case (3.3%) postoperatively.Conclusion: Porous-coated metaphyseal sleeves demonstrated excellent rates of survivorship and radiographic ingrowth in the mid-term setting. However, further studies are required to assess their outcomes in the long-term.

Background: Magnetically controlled growing rod (MCGR) treatment for early-onset scoliosis (EOS) has become a widely utilized method of deformity control, but long-term follow-up reports are sparse. We evaluated the outcomes of a large group of consecutive pediatric patients diagnosed with EOS who were treated by MCGR to the endpoint of definitive spinal fusion in a single center. We hypothesized that lessons learned from treating a large volume of MCGR patients would lower the complication rate in comparison to what was previously reported by other studies. Methods: The records of 48 EOS patients with varied etiologies who were treated by MCGR between 2012 and 2022 and reached the end of treatment were analyzed retrospectively for baseline and final radiographic measurements and surgery-related complications. Results: The mean percent of improvement in the major coronal deformity was 51.7±25.0% and the mean T1 to T12 total growth was 52.9±21.9 mm. The total complication rate was 22.9% of which 12.5% required a single unplanned surgery, 6.3% required multiple unplanned surgeries, and 4% did not require any unplanned surgery. Conclusion: MCGR treatment provides adequate control of EOS, enabling satisfactory growth of the thoracic spine. The complication rate in a single large volume center is moderate. Level of Evidence: IV.