Different Types of Manual Therapy Techniques in Patients With Chronic Neck Pain (CNP)

visual analogue scale (VAS). Despite being a subjective evaluation, it has been documented in previous studies its reliability and validity and its sensitivity to the clinical changes. For this reason, this scale has been used in numerous clinical trials on neck pains to evaluate the results. The patient places a vertical mark on a flat horizontal line of 10 cm. One extreme is 0 (no pain) and the other extreme is 10 (maximum pain) and it must be a difference of 2 points in the evaluation range to produce minimal improvement which is clinically significant.

The Neck Disability Index (NDI) is an assessment tool used to record the perceived disability in patients with neck pain .It was developed by Howard Vernon from the well-known and validated Oswestry scale for low back pain. The NDI is a self-administered questionnaire with 10 sections. 7 related to activities of daily living, 2 related to pain and 1 with concentration. Each of the sections is scored from 0 to 5, and the total score is expressed as a percentage relative to the maximum possible. The Spanish version was used in this study. This scale offer a high levels of validity and reliability (infraclass correlation coefficient, ICC: 0.88), is stable against different cultural levels and is consistent and reliable. The minimum detectable change is 5 points out of 50, while it is recommended t 7 points as the minimum difference clinically important.

The ACROM is an instrument that assesses the active range of motion of the cervical segment and has been used in numerous studies to evaluate the results in manual therapy. Furthermore, it has proven to be a reliable method of measuring, providing a range of intra-meter reliability from 0.7 to 0.9 and a range of inter-meter reliability from 0.8 to 0.87. It consists of an inclinometers system. Gravitational inclinometers for flexion-extension and lateral flexion, and magnetic inclinometers for rotation. The patient, sitting in a chair with the goniometer placed over his head, is asked to perform analytical neck movements (flexion, extension, right lateral flexion, left lateral flexion, right rotation and left rotation) to the point of beginning of pain symptoms or, otherwise, to the fullest extent of mobility. Each movement is recorded three times to take the average.

Pressure pain threshold (PPT) was used in this study for measure the mechanical hyperalgesia. A digital algometer (FDX 25, Wagner Instruments, Greenwich, CT, USA) comprised of a rubber head (1 cm2) attached to a pressure gauge, was used to measure PPTs. Force was measured in kilograms/f (kgf). The measures were taken 3 times at the cervical spine (C2 spinous process), with an interval of 30 seconds between each of the measurements. An average of the 3 measurements was calculated to obtain a single value for each of the measured points in each of the assessments. The assessor localized the spinous process of C2.