Introduction: Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction in adults. Diminished hand strength and dexterity in CSM is a major contribution to disability. The goal of this study was to establish the functional impact of CSM severity on hand function using quantitative testing and evaluate the response to intervention.

Methods: Consecutive adult patients from a single institution with plans for surgical treatment of CSM were prospectively enrolled. Demographics, clinical history, physical exam, modified JOA score were collected. Patients underwent preoperative and posteroperative functional hand testing at 6 weeks: 1) grip strength (Jamar dynamometer), 2) pinch strength (palmar pinch gauge), 3) dexterity (9-hole peg test). Preoperative and postoperative test results were compared to evaluate the impact of surgery; changes were expressed as continuous variables and as proportion achieving minimum clinically important differences (MCID). For analysis, patients were stratified into mild, moderate, and severe myelopathy based on mJOA score (=15, 12-14, =11). Significance was defined as p<.05).

Results: 33 patients were enrolled (Age: 58.1±13.1, Gender: 51.5% Male). Primary presenting symptoms were neck pain (11/33), numbness (7/33), and upper extremity weakness (4/33). 10/33 patients had severe myelopathy, 12/33 had moderate myelopathy, and 11/33 had mild myelopathy. Preoperative pinch and grip strength were lower in severe CSM (p=.014). 20/60 patients underwent anterior approach decompression, with mean of 3 levels treated. Significant improvement was observed in dominant grip strength (p=.004), non-dominant grip strength (p=.008), and dominant hand dexterity (p=.001); no significant improvement was observed in pinch strength (p=.054). 11/33 patients achieved MCID in dominant grip strength at 6 weeks; greatest proportion of patients improved in the moderate (58.3%) compared to low (30%) and high (9%) mJOA groups.

Conclusions: Patients with myelopathy demonstrate improvement in hand function following surgery, particularly in the moderate group.

Patient Care: Cervical spondylotic myelopathy is a common and highly disabling disease entity. Understanding the functional consequences of CSM and the trajectory of expected improvement will facilitate better patient counseling and prognostication.

Learning Objectives: By the conclusion of this session, participants should be able to (1) describe the functional impact of cervical myelopathy on hand function, (2) discuss the association of quantitative objective measures with known metrics, (3) identify the quantitative gains in hand strength and function following surgical intervention for CSM.

References: 1. J. C. Kelly, P. J. Groarke, J. S. Butler, A. R. Poynton, J. M. O'Byrne, The natural history and clinical syndromes of degenerative cervical spondylosis. Advances in orthopedics 2012, 393642 (2012). 2. A. Singh, H. A. Crockard, Quantitative assessment of cervical spondylotic myelopathy by a simple walking test. Lancet 354, 370 (Jul 31, 1999). 3. A. Singh et al., A summary of assessment tools for patients suffering from cervical spondylotic myelopathy: a systematic review on validity, reliability and responsiveness. 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 24 Suppl 2, 209 (Apr, 2015).