Design and testing of an orthopedic robot for deformity correction

Abstract

Deformity correction has positive significance for limb function reconstruction. To reduce the workload of the physicians and enhance the intelligence level of deformity correction, a wearable orthopedic robot based on traditional deformity correction devices is proposed, and the methodology for deformity correction is studied. By utilizing the homogeneous coordinate transformation method, the inverse kinematics of the robot is derived. Based on the approach of PointNet++, the small-batch gradient descent optimization method is used to train the model, achieving effective segmentation of the point cloud of the robotic system. The mirrored registration strategy based on the healthy contralateral bone is adopted, with the SAC-IA (Sample Consensus Initial Alignment) method for coarse registration and the ICP (Iterative Closest Point) method for fine registration, to measure the deformity parameters of the bone accurately. A physical prototype of the orthopedic robot is constructed, relevant experimental parameters are obtained through the optical measurement equipment, and the robot is driven to perform the deformity correction task based on the inverse kinematics solution. Experimental results confirm the clinical viability of the proposed orthopedic robot.

Keywords

Limb deformity / Orthopedic robot / Parameter measurement / Deformity correction

CRediT authorship contribution statement

Xiaoyong Wu: Writing – original draft, Funding acquisition. Cao Yang: Formal analysis, Data curation. Jie Wang: Software, Investigation. Jie Zhou: Visualization, Validation. Kanglai Tang: Supervision, Conceptualization. Lin Guo: Supervision, Methodology.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

This research is supported the National Natural Science Foundation of China (52305248), the China Postdoctoral Science Foundation, China (2023M734262), the Chongqing Science and Technology Commission of China (CSTB2024NSCQ-MSX0405), the Chongqing Postdoctoral Research Project, China (2023CQBSHTB3070), the Science and Technology Research Program of Chongqing Municipal Education Commission, China (HZ2021011). The first author acknowledges the scholarship from the Chinese Scholarship Council to support his research at the National University of Singapore, Singapore.

Appendix A. Supplementary data

Supplementary material related to this article can be found online at https://doi.org/10.1016/j.birob.2026.100279.

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