The Effects Of Jaw Sensorimotor System In The Treatment Of Neck Pain And Dysfunction

The study will be focused on non- specific chronic neck pain patients. The primary objective is to study the effects of jaw sensorimotor system in the treatment of patients with neck pain and dysfunction. It will be randomized controlled trail with the estimated sample size of 80 with both genders. The experimental group will be performed Jaw opening-closing movements with active neck flexion and extension movements and control group will be performed active neck flexion and extension movements. Both groups will be received isometric strengthening exercises, Postural Advice and Home Exercise Program with Dairy. Numeric Pain Rating scale (NPRS), Neck disability Index (NDI), Neck Proprioception tests and Neck muscles endurance test will be used as outcome measures at day 0 and week 6 for treatment effect in both groups. Tables and graphs will used for demographic descriptions and appropriate statistical tests will be applied to establish treatment effect within and between groups.

Study Design : Randomized Controlled Trial Settings: IPM&R (Institute of Physical Medicine and Rehabilitation). This institute is a part of Dow University of Health Sciences (Karachi-Pakistan). Duration of study: 18 months after IRB approval Sample population: Non-specific chronic neck pain Sample size calculation Using carried out using PASS Version 11 two sample t test with 95% confidence of interval and 80% power of test, mean of NDI (experimental 16.83± 2.3 and 19.13 ± 2.2) calculated sample size is 16 per group which we have increased up to 40 in each group (Experimental & Control) including 8 patients as a dropout rate per group (makes at least 32 patients per group). Sampling technique: Non probability, purposive sampling technique Inclusion criteria: Both genders 18 years to 50 years Participants with history neck of more than 3 months with no related conditions Non radiating pain to arms Diagnosed as Nonspecific Chronic Neck pain by consultants NPRS-Numeric Pain Rating Scale score 3 to 8 NDI- Neck Disability Index : score 5 to 34 No TMJ pain or dysfunction Exclusion NPRS-Numeric Pain Rating Scale Score 1 & 2 and score 9 & 10 (Score 1 & 2 mild pain and Score 9 & 10 worst pain) NDI- Neck Disability Index : Score 0 to 4 (no disability) and score 35 to 50(Complete disability) Specific or nonspecific Acute Neck pain (Less than 7 days) Neck pain- Specific or nonspecific Sub acute (pain history more than seven days however less than three months) Neck pain- Specific Chronic (pain history more than 3 months) TMJ Dysfunction WAD (Whiplash Associated Disorders) Cervical spondylosis Rheumatoid arthritis Instability of spine Facial injury or dental infection Any type of infection of body Neck or spinal segment fracture Spinal tumor or any type of tumor/cancer Unexplained headache Post cervical spine surgical cases Signs and symptoms of Cervical spine stenosis Signs and symptoms of disc bulge or herniation of cervical spine Radiating neck pain or Radiculopathy of cervical spine Cognitive impairment Neurological conditions (MS/PD/CVA/MND) Application of injection therapy in cervical spine Red flags ( Episode of Double vision, Dysarthria, Dysphasia, Drop Attack Dizziness, Double vision, Gait disturbance) Assessments: After consent filling form, a physiotherapy assessment form will be completed. Outcome measures (Variables): i. NPRS ii. NDI iii. Neck Proprioception test iv. Neck Muscles Endurance Test Treatment assignment (allocation): In this study, the treatment assignment will be completed using randomization technique. In this study, based on inclusion and exclusion criteria, required numbers of sample size participants will recruit first as mentioned earlier using non probability sampling technique. Estimated total 80 patients (40 patients per group including dropout rate) (makes at least 32 patients per group) will be selected. Total 80 study population will be divided further out in two groups based on gender for giving equal opportunity to participate in this study. 40 male patients (20 for experimental and 20 for control group) and 40 female patients (20 for experimental and 20 for control group) via simple randomization technique using computer generated Microsoft Excel sheet. The above mentioned process will be run for male and female parallel or separately depending on the frequency of the patients. Patients will not be selected in this study based on inclusion criteria, refer to the physiotherapy OPD for assessment and treatment. Blinding: Physiotherapist with minimum two years job experience will be selected and physiotherapist will receive training on how to perform the assessment. Treatment blinding will be achieved by asking physiotherapist to complete initial assessment forms with all outcome measures (pre- intervention) to all subjects (referred patients) with non specific chronic neck pain and dysfunction. The physiotherapists will remain unaware about who will be selected as research sample participants including unaware about experimental and control groups. At the time of getting consent, patients will be made aware of the relevant details about the research study, however they will remain unaware of their own group allocation. The principal investigator alone will administer the treatment. The outcome measurements will be taken at day 0 (pre-intervention) and then week 6 outcome measurements (post intervention) will be recorded by physiotherapist. INTERVENTION: TREATMENT REGIMES FOR EXPERIMENTAL AND CONTROL Experimental group A: Jaw opening-closing movements Active jaw movements Active neck exercises B: Isometric strengthening exercises (Same as control group) C: Postural Advice and Home Exercise Program with Dairy (Same as control group) Control group: A: Active neck exercises. B: Isometric strengthening exercises C: Postural Advice and Home Exercise Program with Dairy Postural advice and home exercise program Postural Advise. Maintain upright posture while sitting. Avoid prolonged neck bending. Avoid twisting movement of the neck. Use a suitable pillow to maintain cervical spine. Adjust computer screen at eye level. Avoid constant use of mobile or similar device to prevent excessive strain over neck joints and muscles. Carry light and even weight in both hands while shopping and other chores. Stay hydrated. Home Exercise Program (unsupervised) The following home exercise program will be instructed to all subjects with request to repeat the program 3 times a day. Forward flexion (Self Resisted), 6 sec hold, number of repetitions 15 Right side flexion (Self Resisted ), 6 sec hold, number of repetitions 15 Left side flexion (Self Resisted) x 6 sec hold,number of repetitions 15 Backward flexion (Self Resisted) x 6 sec hold, number of repetitions 15 Home Dairy A home dairy will be provided to maintain home exercise program record. Frequency and Duration of Treatment: Non-specific Chronic Neck Pain (more than 3 months history of pain) Initial Assessment (week 1) 60 minutes, First treatment session (week1) 40 minutes, 3 treatment sessions per week (week- 2-6 ) 40 minutes, Final Assessment (week 6) 60 minutes. ETHICAL CONSIDERATIONS It will be gained from the Ethical Committee of the University before study Written informed consent will be taken from all the patients All information and collected data will be kept confidential. Participants will remain anonymous throughout the study. The Participants will be informed that there are no disadvantages or risks on the procedure of the study. Participants will also be informed that they will be free to withdraw at any time during the process of the study. DATA COLLECTION Data Collection Procedure After IRB approval, Data will be collected November 2018 (Subject to approval). Collection of data will be initiated once approval of synopsis will be taken. Patients will be recruited from IPM&R and consultants will assess and screen patients as indicated and will pass on to physiotherapy department with diagnosed of non specific chronic pain. Initial screening proforma will be completed by a physiotherapist based on inclusion and exclusion criteria. Non probability sampling technique will be used for recruitment of patients A written consent form will be taken from all participants Participants will be divided into two groups (Experimental and control groups) as mentioned above. Assessment form including outcome measures will be completed on first visit by a trained physiotherapist with experience in the area field of physiotherapy practice at least 2 years. The selected outcome measures will be taken on day 0 (pre intervention), and week 6 (post intervention) will be completed by physiotherapist. Treatment will be performed for 6 weeks with postural advice and home exercise program with dairy record by principal investigator.

A: Jaw opening-closing movements Active jaw movements Active neck exercises B: Isometric strengthening exercises (Same as control group) C: Postural Advice and Home Exercise Program with Dairy (Same as control group)

A: Active neck exercises Active neck exercises Active jaw movements (Active Jaw movement will not be perform in this group) B: Isometric strengthening exercises C: Postural Advice and Home Exercise Program with Dairy i: Postural Advise ii: Home Exercise Program (unsupervised) iii: Home Dairy Frequency and Duration of Treatment Non-specific Chronic Neck Pain (more than 3 months history of pain) Initial Assessment (week 1) 60 minutes First treatment session (week1) 40 minutes 3 treatment sessions per week (week- 2) 40 minutes 3 treatment sessions per week (week- 3) 40 minutes 3 treatment sessions per week (week- 4) 40 minutes 3 treatment sessions per week (week- 5) 40 minutes Last treatment session (week 6) 40 minutes Final Assessment (week 6) 60 minutes

Jaw opening-closing movements Patient seated on a normal standard comfortable chair with proper back support and feet placed on the floor with no head support. Active jaw movements The patient will then perform maximal Jaw opening-closing movements at a pace convenient for his/her for 15 times. Three sets with two minutes rest in between will be ensured. Active neck exercises While performing the above movements of jaws, the patient will actively perform active neck exercise (head-neck movements in sagittal plane- Extension- Flexion). Head-Neck extension on jaw opening (Mandible moves vertically downward); and then from Head-Neck extension to natural flexion movement on jaw closing (Mandible moves vertically upward).

Active neck exercises: Patient seated on a normal standard comfortable chair with proper back support and feet placed on the floor with no head support. Note: For Active neck exercise (flexion and extension movements of neck), firstly the patient will perform maximal Jaw opening-closing movements at a pace convenient for his/her for 5 times in order to observe (eyeball observation) the neck extension and flexion as reference point for each individual. Using this reference points, the patient will ask perform below mentioned active neck exercise. Active neck exercises: The patient will then perform active neck exercise (flexion and extension of neck) at a pace convenient for his/her for 15 times. Three sets with two minutes rest in between will be ensured. Active jaw movement: While performing the above movements of neck, the patient will not perform any jaws movements.

Isometric strengthening exercises For flexion the starting position will be upright head and neck. The patient will be asked to hold this position. For extension the starting position will be upright head and neck. The patient will be asked to hold this position. For rotation the starting position will be upright head and neck. The patient will be asked to hold this position. • In all above movements ( flexion, extension & rotation) following method will be followed: Manual resistance will then be applied by the investigator by placing the hand on the patient's forehead, posterior part of the head and lateral part of the head with 6 second hold. 15 repetitions of this exercise will be performed. Three sets with one minute rest in between will be ensured.

Postural Advice and Home Exercise Program with Dairy Postural advice and home exercise program. Postural Advise Maintain upright posture while sitting. Avoid prolonged neck bending. Avoid twisting movement of the neck. Use a suitable pillow to maintain cervical spine. Adjust computer screen at eye level. Avoid constant use of mobile or similar device to prevent excessive strain over neck joints and muscles. Carry light and even weight in both hands while shopping and other chores.•Stay hydrated. Home Exercise Program (unsupervised) (3 times a day) Forward flexion (Self Resisted), 6 sec hold, number of repetitions 15 Right side flexion (Self Resisted ), 6 sec hold, number of repetitions 15 Left side flexion (Self Resisted) x 6 sec hold,number of repetitions 15 Backward flexion (Self Resisted) x 6 sec hold, number of repetitions 15 Home Dairy A home dairy will be provided to maintain home exercise program record.

Assessing the change in pain level: The subject will be graphically or verbally portrayed a simple depiction consisting of a horizontal bar with labels ranging from '0' to '10' (a total of 11 integers)to rate his pain intensity.'0' would be considered as 'no pain'and '10' would indicate worst pain imaginable, whereas values 1 to 3 would indicate mild pain; 4 to 6 as moderate pain and 7 to 10 would indicate severe pain. NPRS has shown to have good sensitivity and it yields data that are best suited for statistical analysis.

Assessing the change in neck disability level: The Neck Disability Scale is a reliable outcome measure to assess the treatment effectiveness for neck disability. It consists of 10 components.

Assessing the change in neck preconception error: The concept adopted from Hallgren and co workers and it will be used as research instrument on baseline and final visits to find out any proprioceptive errors. A Neutral Reference Point (NRP) will be used and asking patient to perform cervical spine range of motion (rotation, flexion and extension). Then measures any overshoot or undershoot of movement with regard to NRP/Starting position using a cervical spine range of motion device.

Assessing the change in neck muscle endurance level: Neck flexor muscle endurance test will be used to measure neck endurance in this study. It is a simple test and easy to apply. It is reliable test and achieved interrater reliability at moderate level among neck pain population. Cervical extensor endurance test is a simple test for measurement neck extensor muscles endurance. It has good inter-rater reliability Kappa =0.800, Kappa SE= 0.109, 95% CL) and easy to administer. Losing of chin tuck position from neutral position of cervical spine is indicating of global weakness of neck muscles (weakness of superficial and deep neck extensor muscles) whist increasing of chin length with neck extension indicates a over activity of superficial extensor muscles and weakness of deep extensor muscles of cervical spine.

Inclusion Criteria: • Both genders 18 years to 50 years Participants with history neck of more than 3 months with no related conditions Non radiating pain to arms Diagnosed as Nonspecific Chronic Neck pain by consultants NPRS-Numeric Pain Rating Scale: score 3 to 8 (Score 3 Ending of mild pain, Score 8 Beginning of worst pain) NDI- Neck Disability Index: score 5 to 34 (5 to 14 Mild disability,15- 24 Moderate disability & 25 to 34 Severity disability) No TMJ pain or dysfunction Exclusion Criteria: • NPRS-Numeric Pain Rating Scale: Score 1 & 2 and score 9 & 10 (Score 1 & 2 mild pain and Score 9 & 10 worst pain) NDI- Neck Disability Index : Score 0 to 4 (no disability) and score 35 to 50(Complete disability) Specific or nonspecific Acute Neck pain (Less than 7 days) Neck pain- Specific or nonspecific Subacute( pain history more than seven days however less than three months) Neck pain- Specific Chronic (pain history more than 3 months) TMJ Dysfunction WAD (Whiplash Associated Disorders) Cervical spondylosis Rheumatoid arthritis Instability of spine Facial injury or dental infection Any type of infection of body Neck or spinal segment fracture Spinal tumor or any type of tumor/cancer Unexplained headache Post cervical spine surgical cases Signs and symptoms of Cervical spine stenosis Signs and symptoms of disc bulge or herniation of cervical spine Radiating neck pain or Radiculopathy of cervical spine Cognitive impairment Neurological conditions (MS/PD/CVA/MND) Application of injection therapy in cervical spine Red flags ( Episode of Double vision, Dysarthria, Dysphasia, Drop Attack, Dizziness, Double vision, Gait disturbance)

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