Background: Forward head posture affects many individuals and can cause pain and dysfunction in the muscles and joints of the head, neck, and shoulders. Objectives: This study aimed to assess muscle activity and onset time of cervical and scapular muscles during 180° shoulder flexion and abduction in individuals with normal head posture (NHP) and in those with forward head posture (FHP), both before and after correction. Design: Cross-sectional study. Methods: Thirty-six individuals were divided into FHP and NHP groups. Muscle activity and muscle contraction onset time of the splenius capitis, sternocleidomastoid, upper middle and lower trapezius, and serratus anterior muscles were measured during shoulder flexion and abduction using wireless surface electromyography. Results: The FHP group exhibited increased muscle activity compared to the NHP group (P<.05), notably in the sternocleidomastoid and middle trapezius muscles, more so during shoulder abduction than flexion (P<.05). Regarding muscle contraction onset time, sternocleidomastoid onset was fastest during shoulder abduction in the FHP group (P<.05), while serratus anterior onset was slowest during both shoulder abduction and flexion (P<.05). Conclusion: These findings highlight distinct muscle activity and muscle contraction onset time patterns based on head posture and shoulder movement. Selective muscle activation strategies may help reduce heightened sternocleidomastoid and trapezius activity and enhance serratus anterior engagement in individuals with FHP.

PURPOSE: 본 연구의 목적은 둥근어깨자세(round shoulder posture)와 전방머리자세 (forward head posture)에 따라 폐활량 측정과 산소포화도 및 횡격막 움직임 크기의 상관관계를 알아보는 것이다. METHODS: 연구의 대상은 만성 심장질환 및 호흡기 질환을 가지고 있거나, 정신적, 인지적 장애가 있는 자, 척추옆굽음증(scoliosis)이 있는 자, 목과 갈비뼈 손상이나 수술 병력이 없는 50명의 자원한 사람으로 선정되었습니다. 통계분석은 피어슨(Pearson)의 상관분석을 실시한다. RESULTS:둥근어깨자세는 FVC,FEV1,FEV1/FVC%,PEF 에 대해 양의 상관계수를 보이고 이중 PEF가 가장 상관성이 높았다(p<.05). 횡격막 움직임의 크기(DMD)에 대해서도 양의 상관계수를 보였다. 그러나 TAD(table acromion distance)와는 음의 상관관계를, SPO2는 PM/C7~acro, TAD(table acromion distance) 둘다 음의 상관관계가 나타났다(P>.05). 전방머리자세는 CVA와 CRA 모두 FVC,FEV1,FEV1/FVC, PEF 비율에 대해 유의한 상관관계가 없다(p>.05). CRA와 DMD에는 유의한 차이가 있는 음의 상관관계가 나타났지만(p<.05), CVA와 DMD에는 유의한 상관관계가 발견되지 않았다. 또한 CVA와 CRA 모두 SPO2에 대해 유의한 상관관계가 없다(p>.05). CONLUSION: 결론적으로 전방머리자세의 각도와 둥근어깨 자세에 따라 폐활량과 횡격막 움직임에 영향을 미친다는 것을 확인 할 수 있었다. 하지만 좀더 많은 인원과 대상자들의 경직된 자세에 대해 제한할 방법을 추가적으로 찾을 필요가 있다.

Background: For the treatment of forward head posture (FHP) and forward shoulder posture, methods for strengthening scapular retractors and deep cervical flexors and stretching pectoralis and upper cervical extensors are generally used. No study has yet assessed whether suboccipital release (SR) followed by cranio-cervical flexion exercise (CCFE) (SR-CCFE) will result in a positive change in the shoulders and neck, showing a “downstream” effect. Objects: The purpose of this study was to investigate the immediate effects of SR-CCFE on craniovertebral angle (CVA), shoulder abduction range of motion (ROM), shoulder pain, and muscle activities of upper trapezius (UT), lower trapezius (LT), and serratus anterior (SA) and LT/UT and SA/UT muscle activity ratios during maximal shoulder abduction in subjects with FHP. Methods: In total, 19 subjects (7 males, 12 females) with FHP were recruited. The subject performed the fifth phase of CCFE immediately after receiving SR. CVA, shoulder abduction ROM, shoulder pain, muscle activities of UT, LT, and SA, and LT/UT and SA/UT muscle activity ratios during maximal shoulder abduction were measured immediately after SR-CCFE. A paired t-test and Wilcoxon signed-rank test were used to determine the significance of differences in scores between pre- and post-intervention in the same group. Results: The CVA (p<.001) and shoulder abduction ROM (p<.001) were increased significantly postversus pre-intervention. Shoulder pain was decreased significantly (p<.001), and LT (p<.05) and SA (p<.05) muscle activities were increased significantly post- versus pre-intervention. The LT/UT muscle activity ratio was increased significantly post- versus pre-intervention (p<.05). However, there was no significant change in UT muscle activity and SA/UT muscle activity ratio between pre- and post-intervention (p˃.05). Conclusion: SR-CCFE was an effective intervention to improve FHP and induce downstream effect from the neck to the trunk and shoulders in subjects with FHP.