McKenzie neck exercise versus cranio-cervical flexion exercise on strength and endurance of deep neck flexor muscles, pain, disability, and craniovertebral angle in individuals with chronic neck pain: a randomized clinical trial

ABSTRACT

Purpose

To compare the effectiveness of McKenzie neck exercise and cranio-cervical flexion (CCF) exercise on strength and endurance of deep neck flexor (DNF) muscles, pain, disability, and craniovertebral angle (CVA) in individuals with chronic neck pain.

Methods

Forty individuals with chronic neck pain were randomly allocated to the McKenzie neck or CCF exercise group. Each group performed exercises at home daily. The strength and endurance of DNF muscles were measured at baseline, immediately after the first exercise session, and each week follow-up for six weeks. Average pain over the past week was measured at baseline and each week follow-up for six weeks. Disability and CVA were measured at baseline and the end of six weeks.

Results

At six weeks, both groups exhibited significant improvements across all outcome variables (p < 0.001) but there were no differences between groups (p > 0.05). The significant difference from baseline in the strength of DNF muscles was observed as early as the second week of each intervention (p ≤ 0.001). The significant difference from baseline in the endurance of DNF muscles was observed as early as the first week in the CCF exercise group (p < 0.05) and the second week in the McKenzie neck exercise group (p < 0.05). A significant decrease in pain intensity from baseline was observed after the first week in the McKenzie neck exercise group (p < 0.001) while it was after the second week in the CCF exercise group (p < 0.05).

Conclusion

Both the McKenzie neck exercise and CCF exercise produced similar effects in enhancing the strength and endurance of the DNF muscles, decreasing pain, alleviating neck disability, and improving the CVA.

KEYWORDS:

• Chronic neck pain
• deep neck flexors
• exercise
• McKenzie
• craniocervical flexion
• cervical spine

Abbreviations

DNF	=	deep neck flexor
CVA	=	craniovertebral angle
CCF	=	craniocervical flexion
NDI	=	Neck Disability Index
CPI	=	Cumulative Performance Index

Acknowledgements

The authors would like to thank all the research assistants for collecting data, and the patients for giving their permission for their anonymous data use. We thank Dr. James M. Brimson (Research Unit for Innovation and International Affairs, Faculty of Allied Health Sciences, Chulalongkorn University) for proofreading this manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/10669817.2024.2337979

Additional information

Funding

This research was supported by the 90^th Anniversary of Chulalongkorn University Fund (Ratchadaphiseksomphot Endowment Fund).

Notes on contributors

Sawita Chaiyawijit

Sawita Chaiyawijit is a MSc Candidate in physical therapy, majoring in Musculoskeletal System at Chulalongkorn University, Thailand.

Rotsalai Kanlayanaphotporn

Rotsalai Kanlayanaphotporn is an associate professor in the Physical Therapy Department at Chulalongkorn University, Thailand. Her research interests are focused on patient outcomes, exercise therapy, and manual therapy for treating musculoskeletal pathologies.