Participants in this group will receive percussion-based vibration therapy applied using a percussion massage device (Compex Fix 2.0) with a soft head attachment. Therapy will target trapezius, levator scapula, and cervical paravertebral muscles along their origin-insertion lines for 3 minutes per muscle group. Sessions will be conducted 3 days per week over 3 weeks, alongside conventional physiotherapy, including heat therapy (20 min), Transcutaneous Electrical Nerve Stimulation (TENS - 100 Hz), range-of-motion (ROM) exercises (2 sets of 10 repetitions, 2-second holds at end-range), and isometric strengthening exercises (2 sets of 10 repetitions, 6-second holds per direction).

Participants will receive instrument-assisted soft tissue mobilization applied using specially designed stainless-steel instruments. Techniques (Sweep, Fan, Brush) will be applied to cervical and upper-back musculature (splenius, suboccipital, upper-middle-lower trapezius) and related fascia between C1-T1 vertebrae, parallel to muscle fibers for approximately 6 minutes per session. Each technique will consist of 8-10 repetitions. Treatments will occur 3 sessions per week for 3 weeks, alongside conventional physiotherapy interventions (heat therapy for 20 minutes, TENS at 100 Hz, ROM exercises, and isometric strengthening exercises as described above).

Participants in this control group will receive conventional physiotherapy treatment alone. The treatment includes heat therapy applied to the cervical region for 20 minutes, TENS application at a frequency of 100 Hz to painful areas, ROM exercises performed in all cervical directions (2 sets of 10 repetitions, 2-second holds at end-range), and isometric strengthening exercises in cervical flexion, extension, and lateral flexion directions (2 sets of 10 repetitions, 6-second holds per repetition). Sessions will take place 4 days per week for 3 weeks.

Participants in this group will receive percussion-based vibration therapy applied using a percussion massage device (Compex Fix 2.0) with a soft head attachment. Therapy will target trapezius, levator scapula, and cervical paravertebral muscles along their origin-insertion lines for 3 minutes per muscle group.

This assessment measures joint position sense-a component of proprioception-which provides information regarding the speed and direction of active and passive movements without visual cues.Participants will be seated at a distance of 100 cm from a target board measuring 90x80 cm. A laser pointer will be secured to the participant's head using a suitable headband. Participants will initially align the laser pointer vertically onto the center (origin) of the target board with their eyes open. They will then flex their head forward and subsequently return to the neutral position, realigning the pointer to the center. Next, participants will repeat the same process with their eyes closed. After performing cervical flexion, they will attempt to return their head to the perceived neutral position without visual assistance. The deviation from the origin will be measured and recorded as an indicator of joint position sense accuracy.

The Visual Analog Scale (VAS) will be used to evaluate participants' pain intensity. The VAS consists of a horizontal line measuring 10 cm, where '0' represents "no pain" and '10' represents "unbearable pain." Participants will be asked to mark the point that represents their perceived level of pain on this scale. The distance from the starting point (0 cm) to the participant's mark will be measured with a ruler and recorded.