The goal of the cross-sectional study is to explore the impact of neck pain on tongue pressure in the middle-aged and elderly population and analyze the effects of different cranio-cervical positioning on tongue pressure performance.

The main questions it aims to answer are:

1. Do middle-aged and elderly individuals with chronic cervical pain exhibit reduced maximal tongue pressure compared to those without cervical pain?
2. What are the effects of different cranio-cervical positioning on tongue pressure performance?

Participants will complete all the assessments on the day of testing.

1. For Quality assurance plan that addresses data validation and registry procedures:

(1) Relevant data will be recorded by the researchers. All assessments will be conducted in the Orthopedic Laboratory at National Yang Ming Chiao Tung University, where the equipment is regularly maintained and monitored.

2. For Standard operating procedures to address registry operations and analysis activities:

(1 ) Participants will be recruited from clinics and communities in the Taipei and New Taipei City. Collected data will include personal information such as height, age, weight, and the number of removable dentures. Data management and analysis will be conducted using laboratory-designated computers for data storage and processing. Any adverse events, such as throat or tongue soreness occurring within 1-2 days after testing, will be recorded and reported to the researchers.

3. For Sample size assessment:

(1) Total forty participants aged between 50-65 years.

4. For missing data:

(1) This study is a cross-sectional, single-session assessment, and therefore the likelihood of missing data is minimal and no specific handling procedures are needed.

5. For statistical analysis:

(1) Data analysis for this study was conducted using SPSS software version 29.0. Continuous and categorical variables were compared between the two groups using independent t-tests and chi-square tests. Other outcomes will be analyzed using two-way mixed ANOVA, independent t-tests, or Pearson's correlation coefficient to compare differences between groups or examine associations. The significance level is set at 0.05, with p-values less than 0.05 considered statistically significant.

1. Inclusion Criteria (chronic cervical pain group):

1. Aged between 50-65 year olds
2. Chronic neck pain (caused by specific neck movements or prolonged neck posture)
3. Cervical pain duration: at least 3 months within the past year
4. Cervical pain intensity: during activity or rest, as measured by the Numeric Pain Rating Scale, must have an average score of at least 3 over the past two weeks
5. No anti-inflammatory or painkillers can be used within 48 hours prior to the test

2. Inclusion Criteria (healthy group):

1. Matching gender, age, and body mass index with those in the chronic cervical pain group
2. No cervical pain has occurred within the past 6 months

3. Exclusion Criteria:

1. Neurological diseases that may affect tongue pressure readings, such as stroke or Parkinson's disease
2. Head or neck surgery in the past year
3. Severe head or neck injuries (e.g., whiplash from a car accident) in the past year
4. Diagnosed with cervical radiculopathy or myelopathy with symptoms in the form of numbness or tingling, or fail relative clinical tests (spurling's/ cervical distraction/ cervical rotation test/ upper limb tension test-1/ Hoffman sign)
5. History of head or neck deformities or cancer
6. History of head or neck radiation therapy
7. Diagnosed with dysphagia
8. Experience pain or restricted movement in the temporomandibular joint (TMJ) during chewing in the last 6 months
9. Require anticonvulsants or antidepressant medications
10. Cognitive impairments preventing understanding of the test order or communication

Community and regional clinics in Taipei or New Taipei