MEASURES OF NECK MUSCLE STRENGTH AND THEIR MEASUREMENT PROPERTIES IN ADULTS WITH CHRONIC NECK PAIN — A SYSTEMATIC REVIEW

D. Abichandani¹, J. Tong Yuk Ting², E.E. Cancino², S. Althobaiti², D. Falla²

¹London South Bank University, Physiotherapy, London, United Kingdom, ²University of Birmingham, Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, Birmingham, United Kingdom

Background: Measurement of neck muscle strength is common during the assessment of people with chronic neck pain (CNP). This systematic review evaluates the measurement properties (reliability, validity, and responsiveness) of neck muscle strength measures in people with CNP.

Purpose: People with neck pain commonly present with altered physical function including neck muscle weakness. Neck muscle strength training is known to be an effective intervention for patients with neck pain, and an association exists between the extent of the reduction in neck pain and disability and an increase in neck strength following neck strengthening in people with chronic neck pain (CNP). The measurement of neck strength is therefore relevant to determine the presence of neck muscle weakness and to monitor strength changes over time as it serves as an important objective marker throughout the course of rehabilitation as are other objective markers.

Methods: This systematic review followed a PROSPERO registered protocol (CRD42021233290). Electronic databases MEDLINE (OVID interface), CINAHL, SPORTDiscuss via (EBSCO interface), EMBASE (OVID interface), and Web of Science were searched from inception to 21 June 2021. Screening, data extraction, and quality assessment (Consensus-based Standards for the selection of Health Measurement Instruments (COSMIN) checklist) were conducted independently by two reviewers. The overall strength of evidence was evaluated using the modified Grading of Recommendations Assessment, Development and Evaluation.

Results: From 794 records, nine articles were included in this review which concerned six different neck strength outcome measures. All studies evaluated reliability and one evaluated construct validity. The reliability of neck strength measures ranged from good to excellent. However, the risk of bias was rated as doubtful/inadequate for all except one study and the overall certainty of evidence was rated low/very low for all measures except for the measurement error of a handheld dynamometer.

Conclusions: A multitude of measures are used to evaluate neck muscle strength in people with CNP, but their measurement properties have not been fully established. Further methodologically rigorous research is required to increase the overall quality of evidence.

Implications: Future implications for research and clinical practice:
1. A range of outcome measures are used to examine neck muscle strength and as such, there remains a lack of consensus and standardized approach in performing neck strength measurements.
2. This review unveiled methodological flaws in existing studies evaluating measurement properties of neck strength measures. Future research should carefully consider study design and reporting of results (e.g., better description of examiners, adequate time between measurements, reporting of blinding of examination, outlining statistical model for data analysis, etc.) in order to ensure future results with higher overall quality of evidence.

Funding acknowledgements: Not applicable

Keywords:
Neck pain
Muscle strength
Measurement

Topics:
Musculoskeletal: spine
Education: clinical
Pain & pain management

Did this work require ethics approval? No

Reason: As original data collection was not involved in this systematic review, ethical approval was not required.