Development and Evaluation of a New Assessment Tool for Myelopathy Hand

Abstract

Background: Impairment of hand function in myelopathy patients is commonly observed. However, no objective and effective evaluation method has been widely accepted in clinical practice. The study aimed to evaluate the validity, reliability and effectiveness of a new assessment tool, Myelopathy-hand Functional Evaluation System (MFES), in evaluating the hand dysfunction of myelopathy-hand in the 10-s hand grip-and-release test (10s G-R test).Methods: MFES mainly consists of a pair of wise-gloves and a computer with software. All included patients received optimal surgery treatment. The Japanese Orthopedic Association (JOA) scores of each patient were marked and the hand function was evaluated using MFES before, and 6 months after surgery. All patients were asked to perform the 10s G-R test and the hand movements were simulated and converted into waveforms by MFES. The waveform parameters were measured and analyzed. The validity and test-retest reliability were assessed.Results: The Bland-Altman showed significant agreement with a low bias and narrow limits of agreement. The test-retest reliability was high with a significant value (r=0.911). The JOA scores and the number of G-R cycles significantly increased after surgery. Correspondingly, the waveforms of ulnar three fingers were significantly higher and narrower, along with the significantly declined average time per cycle in postoperative. The number of the first five-second segment (N1) was significantly higher than the second-five segment (N2) in postoperative, indicating the recovery of spinal cord function after surgery. The preoperative number of cycles was positively correlated with the improvement rates of JOA scores. And the increased number of cycles was significantly correlated with the improvement rates of JOA scores.Conclusion: MFES is a reliable and valid assessment tool for myelopathy hand, which can detect small changes of neurological function after decompression surgery.