Kinematic alteration in three-dimensional reaching movement in C3-4 level cervical myelopathy

PLoS One. 2023 Nov 30;18(11):e0295156. doi: 10.1371/journal.pone.0295156. eCollection 2023.

Abstract

Object: This study aimed to compare the reaching movement between two different spinal cord compression level groups in cervical myelopathy (CM) patients.

Methods: Nine CM patients with maximal cord compression at the C3-4 level (C3-4 group) and 15 CM patients with maximal cord compression at the C4-7 level (C4-7 group) participated in the study. We monitored three-dimensional (3D) reaching movement using an electronic-mechanical whack-a-mole-type task pre-and post-operatively. Movement time (MT) and 3D movement distance (MD) during the task were recorded. An analysis of variance for split-plot factorial design was performed to investigate the effects of compression level or surgery on MT and MD. Moreover, we investigated the relationship between these kinematic reaching parameters and conventional clinical tests.

Results: The 3D reaching trajectories of the C3-4 group was unstable with higher variability. The C3-4 group showed longer MT (p < 0.05) and MD (p < 0.01) compared with the C4-7 group both before and after surgery. Moreover, MT was negatively correlated with the Japanese Orthopedic Association score only in the C3-4 group (r = - 0.48).

Conclusion: We found that spinal cord compression at the C3-4 level had a negative effect on 3D reaching movement and the kinematic alteration influenced the upper extremity performance. This new knowledge may increase our understanding of kinematic alteration in patients with CM.

MeSH terms

  • Biomechanical Phenomena
  • Cervical Vertebrae / diagnostic imaging
  • Cervical Vertebrae / surgery
  • Humans
  • Magnetic Resonance Imaging / methods
  • Spinal Cord Compression* / diagnostic imaging
  • Spinal Cord Compression* / surgery
  • Spinal Cord Diseases* / diagnostic imaging
  • Spinal Cord Diseases* / surgery

Grants and funding

Our study was supported by JSPS KAKENHI under Grant number 21K17507. Moreover, the funders had no role in our study design, data collection and analysis, decision to publish, or preparation of the manuscript.