Objective: In spinal surgery, precise identification of high-speed bur milling states is crucial for patient safety. This study investigates whether integrating tactile and auditory perception can enhance the accuracy of milling state detection in robot-assisted cervical laminectomy.
Methods: Based on the mathematical and physical model of vibration and sound in high-speed bur milling bone, the feasibility of employing vibration and sound characteristics to identify the milling states of high-speed bur is studied systematically. Cervical laminectomy was performed on the cervical spine of the sheep. During the signal acquisition process, acceleration sensors and microphones were installed to collect vibration and sound signals, respectively. Seven milling states were set up in the experiment: (1) Milling depths of cortical bone (CTB): 0.5, 1.0, and 1.5 mm; (2) Milling depths of milling of cancellous bone (CCB): 0.5, 1.0, and 1.5 mm; (3) Boundary conditions: high-speed bur idling or complete penetration of bone (PT). The milling speed was set at 0.5 mm/s, the milling angle was 45°, and the bur diameter was 4 mm. The vibration or sound was extracted by Fast Fourier Transform (FFT) in the frequency domain of the first nine harmonics to generate the feature vector in 9 dimensions (9-D) space. These vibration and sound features were combined to form an 18-D multi-perception spatial vector for subsequent analysis, including five machine learning algorithms: Support Vector Machine (SVM), K Nearest Neighbors (KNN), Naive Bayes (NB), Linear Discriminant Analysis (LDA), and Decision Tree (DT), and deep learning models: Long Short-Term Memory networks (LSTM).
Results: Based on the 18-D features of tactile and auditory multisensory fusion, the LSTM model is trained using 6600 sets of high-speed bur milling data. In order to achieve the best performance, a layer-by-layer parameter optimization strategy was used to determine the optimal parameter configuration, and finally, a single-layer LSTM with 12 memory units was constructed. In terms of accuracy and stability, the model is significantly superior to the machine learning algorithms (SVM, KNN, NB, LDA, and DT), and the accuracy of LSTM is 99.32% in the milling states identification of cervical lamina milling with high-speed bur.
Conclusion: Through theoretical analysis and experimental verification, the study built a multi-perception fusion framework based on tactile and auditory perception and accurately identified the cervical vertebra milling states through the LSTM model, which can provide perception means for operational spinal surgery robots in the future.
| [1] |
N. Theodore, “Degenerative Cervical Spondylosis,” New England Journal of Medicine 383 (2020): 159–168.
|
| [2] |
X. Z. Wang, H. Liu, J. Q. Li, et al., “Comparison of Anterior Cervical Discectomy and Fusion With Cervical Laminectomy and Fusion in the Treatment of 4-Level Cervical Spondylotic Myelopathy,” Orthopaedic Surgery 14 (2022): 229–237.
|
| [3] |
M. Teraguchi, N. Yoshimura, H. Hashizume, et al., “Prevalence and Distribution of Intervertebral Disc Degeneration Over the Entire Spine in a Population-Based Cohort: The Wakayama Spine Study,” Osteoarthritis and Cartilage 22 (2014): 104–110.
|
| [4] |
W. Brinjikji, P. H. Luetmer, B. Comstock, et al., “Systematic Literature Review of Imaging Features of Spinal Degeneration in Asymptomatic Populations,” AJNR. American Journal of Neuroradiology 36 (2015): 811–816.
|
| [5] |
K. Daimon, H. Fujiwara, Y. Nishiwaki, et al., “A 20-Year Prospective Longitudinal Study of Degeneration of the Cervical Spine in a Volunteer Cohort Assessed Using MRI: Follow-Up of a Cross-Sectional Study,” Journal of Bone and Joint Surgery. American Volume 100 (2018): 843–849.
|
| [6] |
Y. Tao, F. Galbusera, F. Niemeyer, D. Samartzis, D. Vogele, and H.-J. Wilke, “Radiographic Cervical Spine Degenerative Findings: A Study on a Large Population From Age 18 to 97 Years,” European Spine Journal 30 (2021): 431–443.
|
| [7] |
J. L. Dieleman, J. Cao, A. Chapin, et al., “US Health Care Spending by Payer and Health Condition, 1996–2016,” JAMA 323 (2020): 863–884.
|
| [8] |
S. Z. George, C. Goertz, S. N. Hastings, and J. M. Fritz, “Transforming Low Back Pain Care Delivery in the United States,” Pain 161 (2020): 2667–2673.
|
| [9] |
F. Mg, T. La, and W. , “A Clinical Practice Guideline for the Management of Degenerative Cervical Myelopathy,” Global Spine Journal 7 (2017): 70S–83S.
|
| [10] |
B. Zhu, Y. Xu, X. Liu, Z. Liu, and G. Dang, “Anterior Approach Versus Posterior Approach for the Treatment of Multilevel Cervical Spondylotic Myelopathy: A Systemic Review and Meta-Analysis,” European Spine Journal: Official Publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society 22 (2013): 1583–1593.
|
| [11] |
J. M. Liu, H. W. Peng, Z. L. Liu, X. H. Long, Y. Q. Yu, and S. H. Huang, “Hybrid Decompression Technique Versus Anterior Cervical Corpectomy and Fusion for Treating Multilevel Cervical Spondylotic Myelopathy: Which One Is Better?,” World Neurosurgery 84 (2015): 2022–2029.
|
| [12] |
K. B. Mueller, K. P. Mullinix, and H. F. Bermudez, “How I Do It: En-Bloc Subaxial Cervical Laminectomy Using a High-Speed Drill With a Footplate Attachment,” Acta Neurochirurgica 162 (2020): 311–315.
|
| [13] |
R. Wang, H. Bai, G. Xia, J. Zhou, Y. Dai, and Y. Xue, “Identification of Milling Status Based on Vibration Signals Using Artificial Intelligence in Robot-Assisted Cervical Laminectomy,” European Journal of Medical Research 28 (2023): 203.
|
| [14] |
W. Mualem, C. Onyedimma, A. K. Ghaith, et al., “R2 Advances in Robotic-Assisted Spine Surgery: Comparative Analysis of Options, Future Directions, and Bibliometric Analysis of the Literature,” Neurosurgical Review 46 (2022): 18.
|
| [15] |
Y. Ren, S. Cao, J. Wu, X. Weng, and B. Feng, “Efficacy and Reliability of Active Robotic-Assisted Total Knee Arthroplasty Compared With Conventional Total Knee Arthroplasty: A Systematic Review and Meta-Analysis,” Postgraduate Medical Journal 95 (2019): 125–133.
|
| [16] |
A. Khan, J. E. Meyers, I. Siasios, and J. Pollina, “Next-Generation Robotic Spine Surgery: First Report on Feasibility, Safety, and Learning Curve,” Operative Neurosurgery (Hagerstown, Md.) 17 (2019): 61–69.
|
| [17] |
N. V. Haik, A. E. Burgess, N. C. Talbot, et al., “Robotic Systems in Spinal Surgery: A Review of Accuracy, Radiation Exposure, Hospital Readmission Rate, Cost, and Adverse Events,” World Neurosurgery 195 (2025): 123721.
|
| [18] |
Z. Gao, X. Zhang, Z. Xu, et al., “Mazor X Robot-Assisted Upper and Lower Cervical Pedicle Screw Fixation: A Case Report and Literature Review,” BMC Geriatrics 24 (2024): 916.
|
| [19] |
E. L. Huey, J. Turecek, M. M. Delisle, et al., “The Auditory Midbrain Mediates Tactile Vibration Sensing,” Cell 188 (2025): 104–120.
|
| [20] |
D. Daentzer, B. Welke, C. Hurschler, et al., “In Vitro-Analysis of Kinematics and Intradiscal Pressures in Cervical Arthroplasty Versus Fusion: A Biomechanical Study in a Sheep Model With Two Semi-Constrained Prosthesis,” Biomedical Engineering Online 14 (2015): 27.
|
| [21] |
F. Kandziora, R. Pflugmacher, M. Scholz, et al., “Comparison Between Sheep and Human Cervical Spines: An Anatomic, Radiographic, Bone Mineral Density, and Biomechanical Study,” Spine 26 (2001): 1028–1037.
|
| [22] |
H. J. Wilke, A. Kettler, and L. E. Claes, “Are Sheep Spines a Valid Biomechanical Model for Human Spines?,” Spine 22 (1997): 2365–2374.
|
| [23] |
T. Oberlin, S. Meignen, and V. Perrier, “Second-Order Synchrosqueezing Transform or Invertible Reassignment? Towards Ideal Time-Frequency Representations,” IEEE Transactions on Signal Processing 63 (2015): 1335–1344.
|
| [24] |
M. Tohyama, “Fourier Transform and Superposition of Sinusoidal Functions,” in Sound in the Time Domain (Springer Singapore, 2018), 51–89.
|
| [25] |
S. Hochreiter and J. Schmidhuber, “Long Short-Term Memory,” Neural Computation 9 (1997): 1735–1780.
|
| [26] |
K. Greff, R. K. Srivastava, J. Koutnik, B. R. Steunebrink, and J. Schmidhuber, “LSTM: A Search Space Odyssey,” IEEE Transactions on Neural Networks and Learning Systems 28 (2017): 2222–2232.
|
| [27] |
N. Lonjon, E. Chan-Seng, V. Costalat, B. Bonnafoux, M. Vassal, and J. Boetto, “Robot-Assisted Spine Surgery: Feasibility Study Through a Prospective Case-Matched Analysis,” European Spine Journal: Official Publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society 25 (2016): 947–955.
|
| [28] |
K. I. Al-Abdullah, C. P. Lim, Z. Najdovski, and W. Yassin, “A Model-Based Bone Milling State Identification Method via Force Sensing for a Robotic Surgical System,” International Journal of Medical Robotics + Computer Assisted Surgery: MRCAS 15 (2019): e1989.
|
| [29] |
J. Zhang, Y. Zhang, S. Liu, et al., “Safety Control Strategy of Spinal Lamina Cutting Based on Force and Cutting Depth Signals,” CAAI Transactions on Intelligence Technology 9 (2024): 894–902.
|
| [30] |
C. Shi, M. Li, C. Lv, J. Li, and S. Wang, “A High-Sensitivity Fiber Bragg Grating-Based Distal Force Sensor for Laparoscopic Surgery,” IEEE Sensors Journal 20 (2020): 2467–2475.
|
| [31] |
C.-S. Liu, B.-J. Tsai, and Y.-H. Chang, “Design and Applications of Novel Enhanced-Performance Force Sensor,” IEEE Sensors Journal 16 (2016): 4665–4666.
|
| [32] |
Y. Dai, Y. Xue, and J. Zhang, “Bioinspired Integration of Auditory and Haptic Perception in Bone Milling Surgery,” IEEE/ASME Transactions on Mechatronics 23 (2018): 614–623.
|
| [33] |
Y. Dai, Y. Xue, J. Zhang, and J. Li, “Vibration Feedback Control for Robotic Bone Milling,” IEEE Transactions on Industrial Electronics 70 (2023): 10312–10322.
|
| [34] |
H. Bai, R. Wang, Q. Wang, et al., “Motor Bur Milling State Identification via Fast Fourier Transform Analyzing Sound Signal in Cervical Spine Posterior Decompression Surgery,” Orthopaedic Surgery 13 (2021): 2382–2395.
|
| [35] |
V. Zakeri and A. J. Hodgson, “Automatic Identification of Hard and Soft Bone Tissues by Analyzing Drilling Sounds,” IEEE/ACM Transactions on Audio, Speech and Language Processing 27 (2019): 404–414.
|
| [36] |
G. Xia, Z. Jiang, J. Zhang, R. Wang, and Y. Dai, “Sound Pressure Signal-Based Bone Cutting Depth Control in Robotic Vertebral Lamina Milling,” IEEE Sensors Journal 22 (2022): 10708–10718.
|
| [37] |
E. Yanik, S. Schwaitzberg, G. Yang, et al., “One-Shot Skill Assessment in High-Stakes Domains With Limited Data via Meta Learning,” Computers in Biology and Medicine 174 (2024): 108470.
|
RIGHTS & PERMISSIONS
2025 The Author(s). Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd.