Table 2 Description of the therapeutic exercises performed during the intervention period

Chin tuck in the supine position

Longus colli

Longus capitis

In the supine position, the patient, guided by the Stabilizer Pressure biofeedback device, reaches 5 pressure targets in 2 mmHg increments from a baseline of 20 mmHg until the final level of 30 mmHg by performing a neck curl with the chin tucked. The training starts at the level that the participant can hold steady for 10 s without activation of the superficial neck flexor muscles while performing a slow craniocervical flexion. For each target level, the contraction duration increases to 10 s, and each patient performs 10 repetitions. If three attempts by the patient are successful, then she continues to the next level. The test was stopped when the subject failed to hold for 10 s at the pressure level in any of the 3 repetitions or when she contracted incorrect muscle groups.

Cervical rotation with chin tuck in a sitting position

Longus colli

Longus capitis

Semispinalis Capitus

Semispinalis Cervicis

Sternocleidomastoid

Longissimus Capitis

In a sitting position, the patient rotates her head in both directions (left-right) with simultaneous contraction of the deep neck flexors (with the chin tucked). The movement stops at the point where the patient leaves the axis of rotation and performs both rotation and lateral flexion.

Cervical lateral flexion with chin tuck in a sitting position

Longus colli

Longus capitis

Rectus capitis lateralis

Scalenes

Sternocleidomastoid

Obliquus Capitus Superior

In a sitting position, the patient laterally flexes the head in both directions (left-right) with simultaneous contraction of the deep neck flexors (with chin tucked). The movement stops at the point where the patient leaves the axis of movement and performs both rotation and lateral flexion.

Shoulder horizontal abduction

with external rotation in the prone position

Middle trapezius

Lower trapezius

Rhomboids

Infraspinatus

Teres minor

In the prone position, the patient horizontally abducts and externally rotates the shoulders with the elbow flexed at 90°. The patient lifts both shoulders at the same time, trying to squeeze both scapulae together, avoiding movement of the head, which rests in the neutral position.