Comparison of Upper and Lower Cervical Muscle Strengths Between Subjects With and Without Forward Head Posture

  • Eun, Ji-yeon (Department of Physical Therapy, Graduate School, Yonsei University) ;
  • Kwon, Oh-yun (Department of Physical Therapy, College of Health Science, Laboratory of Kinetic Ergocise Based on Movement Analysis, Yonsei University) ;
  • Hwang, Ui-jae (Department of Physical Therapy, Graduate School, Yonsei University) ;
  • Jung, Sung-hoon (Department of Physical Therapy, Graduate School, Yonsei University) ;
  • Ahn, Sun-hee (Department of Physical Therapy, Graduate School, Yonsei University)
  • Received : 2020.10.08
  • Accepted : 2020.10.27
  • Published : 2020.11.20


Background: Forward head posture (FHP) is common postural malalignment. FHP is described relatively extension to upper cervical and lower cervical is relatively flexion. Although several researchers mentioned the lower cervical flexion posture in FHP, most of the studies related to FHP is focused on the deep cervical flexor function. Objects: The purposes of present study is to compare the cervical strength (upper cervical extension [UCE], lower cervical extension [LCE], upper cervical flexion [UCF], lower cervical flexion [LCF]) between individuals with and without FHP. Methods: Fifty-one participants are recruited. Participants who have the craniovertebral angle (CVA) less than 48 degree were classified to the FHP group (n = 24) and the others were included in without FHP group (n = 27). The cervical strength (UCE, LCE, UCF, LCF) were measured using Smart KEMA strength sensor and the strength data was normalized by body weight. All strength measurement conducted at head and neck neutral position in sitting. Independent t-test was used to compare the cervical strength between individuals with and without FHP. Results: The mean value of CVA was greater in without FHP group than with FHP group (p < 0.000). The strength value of UCF (p < 0.002) and LCE (p < 0.001) was significant less in FHP group than without FHP group. But no significant differences were seen in the LCF and UCE strength between two groups. Conclusion: UCF and LCE weakness in FHP group should be considered to evaluate and manage the individuals with FHP.



  1. Bokaee F, Rezasoltani A, Manshadi FD, Naimi SS, Baghban AA, Azimi H. Comparison of isometric force of the craniocervical flexor and extensor muscles between women with and without forward head posture. Cranio 2016;34(5):286-90.
  2. Ruivo RM, Pezarat-Correia P, Carita AI. Effects of a resistance and stretching training program on forward head and protracted shoulder posture in adolescents. J Manipulative Physiol Ther 2017;40(1):1-10.
  3. Fernandez-de-Las-Penas C, Cuadrado ML, Pareja JA. Myofascial trigger points, neck mobility, and forward head posture in episodic tension-type headache. Headache 2007;47(5):662-72.
  4. Patwardhan AG, Khayatzadeh S, Havey RM, Voronov LI, Smith ZA, Kalmanson O, et al. Cervical sagittal balance: a biomechanical perspective can help clinical practice. Eur Spine J 2018;27(Suppl 1):25-38.
  5. Van Wyk L, Jull G, Vicenzino B, Greaves M, O'Leary S. A comparison of craniocervical and cervicothoracic muscle strength in healthy individuals. J Appl Biomech 2010;26(4):400-6.
  6. Jung SH, Kwon OY, Choi KH, Ha SM, Kim SJ, Jeon IC, et al. Comparison of the thickness of the neck flexor muscles of subjects with and without a forward head posture on the two initial head positions during cranio-cervical flexion exercise. Phys Ther Korea 2015;22(4):44-50.
  7. Son MC, Hwang UJ, Jung SH, Ahn SH, Kim HA, Kwon OY. Comparison of the cross-sectional area of longus colli and muscle activity of sternocleidomastoid in subjects with forward head posture on the two craniocervical flexion methods. Phys Ther Korea 2018;25(2):62-70.
  8. Cagnie B, Cools A, De Loose V, Cambier D, Danneels L. Differences in isometric neck muscle strength between healthy controls and women with chronic neck pain: the use of a reliable measurement. Arch Phys Med Rehabil 2007;88(11):1441-5.
  9. Kim MH, Yi CH, Kwon OY, Cho SH, Yoo WG. Changes in neck muscle electromyography and forward head posture of children when carrying schoolbags. Ergonomics 2008;51(6):890-901.
  10. Nojiri K, Matsumoto M, Chiba K, Maruiwa H, Nakamura M, Nishizawa T, et al. Relationship between alignment of upper and lower cervical spine in asymptomatic individuals. J Neurosurg 2003;99(1 Suppl):80-3.
  11. Salahzadeh Z, Maroufi N, Ahmadi A, Behtash H, Razmjoo A, Gohari M, et al. Assessment of forward head posture in females: observational and photogrammetry methods. J Back Musculoskelet Rehabil 2014;27(2):131-9.
  12. Ylinen J, Salo P, Nykanen M, Kautiainen H, Hakkinen A. Decreased isometric neck strength in women with chronic neck pain and the repeatability of neck strength measurements. Arch Phys Med Rehabil 2004;85(8):1303-8.
  13. van Niekerk SM, Louw Q, Vaughan C, Grimmer-Somers K, Schreve K. Photographic measurement of upper-body sitting posture of high school students: a reliability and validity study. BMC Musculoskelet Disord 2008;9:113.
  14. Lee KJ, Han HY, Cheon SH, Park SH, Yong MS. The effect of forward head posture on muscle activity during neck protraction and retraction. J Phys Ther Sci 2015;27(3):977-9.
  15. Yip CH, Chiu TT, Poon AT. The relationship between head posture and severity and disability of patients with neck pain. Man Ther 2008;13(2):148-54.
  16. Candan SA, Sahin UK, Akoglu S. The investigation of workrelated musculoskeletal disorders among female workers in a hazelnut factory: prevalence, working posture, work-related and psychosocial factors. Int J Ind Ergon 2019;74:102838.
  17. Kim HA, Hwang UJ, Jung SH, Ahn SH, Kim JH, Kwon OY. Effect of horizontal adduction force on infraspinatus and deltoid activities during the side-lying wiper exercise using pressure biofeedback. Phys Ther Korea 2017;24(4):77-83.
  18. O'Leary S, Fagermoen CL, Hasegawa H, Thorsen AS, Van Wyk L. Differential strength and endurance parameters of the craniocervical and cervicothoracic extensors and flexors in healthy individuals. J Appl Biomech 2017;33(2):166-70.
  19. Lewis JS, Green A, Wright C. Subacromial impingement syndrome: the role of posture and muscle imbalance. J Shoulder Elbow Surg 2005;14(4):385-92.
  20. Kim SY, Kim NS, Kim LJ. Effects of cervical sustained natural apophyseal glide on forward head posture and respiratory function. J Phys Ther Sci 2015;27(6):1851-4.
  21. Falla DL, Campbell CD, Fagan AE, Thompson DC, Jull GA. Relationship between cranio-cervical flexion range of motion and pressure change during the cranio-cervical flexion test. Man Ther 2003;8(2):92-6.
  22. Yuill E, Howitt SD. Temporomandibular joint: conservative care of TMJ dysfunction in a competitive swimmer. J Can Chiropr Assoc 2009;53(3):165-72.
  23. Edmondston SJ, Sharp M, Symes A, Alhabib N, Allison GT. Changes in mechanical load and extensor muscle activity in the cervico-thoracic spine induced by sitting posture modification. Ergonomics 2011;54(2):179-86.
  24. Warren GL, Ingalls CP, Lowe DA, Armstrong RB. What mechanisms contribute to the strength loss that occurs during and in the recovery from skeletal muscle injury? J Orthop Sports Phys Ther 2002;32(2):58-64.
  25. Hubal MJ, Rubinstein SR, Clarkson PM. Mechanisms of variability in strength loss after muscle-lengthening actions. Med Sci Sports Exerc 2007;39(3):461-8.