Physical Therapy Korea
pISSN 1225-8962
eISSN 2287-982X
Physical Therapy Korea
General characteristics of the selected studies
| Study | Criteria for recognizing FHP |
General characteristics of participants | Outcomes | Main outcomes |
|---|---|---|---|---|
| Khayatzadeh et al. [13], 2017 | SVA | 13 Fresh-frozen cadaveric cervical spine specimens (9 males, 4 females) Age = 54 ± 15 years |
Muscle length, segmental angular motion | Kinematic changes: C0–C2: Hyperextension occurs C2–C7: Flexion occurs Muscle length changes: Shortened muscles: Occipital extensor muscles Cervical flexor muscles Elongated muscles: Occipital flexor muscles Cervical extensor muscles |
| Patwardhan et al. [16], 2015 | SVA | 10 Cadaveric cervical spines (occiput–T1) Age = 54 (21–59) years |
Segmental angular motion | Forward head displacement: Displacement: 4 cm forward Resulting extension: Approximately 12 degrees of extension between the occiput and C1 Approximately 12 degrees of extension between C1 and C2 Resulting flexion: Approximately 10 degrees of flexion below C5–C6 Study findings on SVA (sagittal vertical axis): Subaxial spinal vertebrae (below C2): Increased SVA results in flexion Axial vertebrae (C0–C2): Increased SVA results in hyperextension |
| Lin et al. [10], 2022 | 1. CVA for NHP = 55 2. CVA for slight FHP = 55° > and < 45° 3. CVA for severe FHP 45° > and 35° < |
6 Cadavers(4 males and 2 females) Age = 86.2 ± 8.7 years |
Deep neck muscle length | Comparison of neutral posture to slight (FHP): Shortening observed: Upper SSC muscle RCP muscles Lengthening observed: Longus capitis muscle Splenius cervicis muscle Comparison of neutral posture to severe FHP: Shortening observed: All occipital extensors (excluding OCS) Lengthening observed: All cervical extensor muscles Superior oblique part of the LCo muscle Comparison of slight FHP to severe FHP: Elongation observed: Superior oblique part of the LCo muscle |
| Fercho et al. [18], 2023 | N = 25(11 females and 15 males) Age = 23.36 ± 2.79 years |
Segmental angular motion | Sitting posture while using a phone: C0–C1 Joint: 33.33 degrees of flexion Subaxial spinal segments: 1.05 degrees of extension Standing while using a phone: C0–C1 region: 27.50 degrees of flexion Subaxial spinal segments: 2.50 degrees of flexion Walking while using a phone: C0–C1 region: 32.03 degrees of flexion Subaxial vertebrae: 3.30 degrees of extension |
|
| Eun et al. [19], 2020 | CVA < 48° | FHP = 24 (15 males) CVA = 44.8° ± 2.0° NHP = 27 (10 males) CVA = 52.5° ± 3.0° Age = 32.6 ± 4.8 years (for all participants) |
Muscle strength (UCE, LCE, UCF, LCF) | Statistical observations: Significant decreases: Strength of LCE Strength of UCF Non-significant changes: Strength of LCF Strength of UCE Significant increase in ratio: LCF strength to LCE strength in the FHP group No significant change in ratio: UCF strength to UCE strength |
| Bokaee et al. [11], 2017 | CVA < 48° | FHP = 35 females Age = 24.94 years (5.13) CVA = 43.76° NHP = 35 females Age = 25.18 years (5.52) CVA = 54.26° |
Cervical muscle thickness (RCP, OCS, SSC, SCM, and LCo) | Statistical observations: Significant increase: Thickness of the SCM muscle in the FHP group Non-significant changes: Increases in the thickness of other muscles (RCP, OCS, SSC, LCo) in the FHP group |
| Goodarzi et al. [9], 2015 | CVA | FHP (n = 20) CVA = 43.43° ± 2.58° Age = 21.30 ± 2.36 years NHP (n = 20) CVA = 55.90° ± 2.25° Age = 21.85 ± 2.87 years |
Extensor muscles thickness at rest (multifidus, SSCe, SSC, Sca and UT) | Statistical observations on muscle groups: No statistically significant changes: Occipital extensor muscles Cervical extensor muscles Thickness observations in the occipital extensor muscle group: Muscles found to be thinner: Sca muscle SSC muscle p-values: The p-values for the Sca and SSC muscles indicated that these muscles were thinner compared to other muscles in the occipital extensor group. |
| Goodarzi et al. [20], 2018 | CVA < 49° | FHP (n = 20) CVA = 43.43° ± 2.58° Age = 21.30 ± 2.36 years NHP (n = 20) CVA = 55.90° ± 2.25° Age = 21.85 ± 2.87 years |
Difference in thickness change of extensor muscles during contraction and relaxation (multifidus, SSCe, SSCa, Sca and UT) | Change in muscle thickness between rest and isometric muscle contraction: Statistically significant decrease: SSC muscle within the occipital extensor muscle group |
| Quek et al. [21], 2013 | CVA | N = 51 (29 females, 22 males) Age = 66 ± 4.9 years (60–78) CVA = 45.6° ± 6.7° (31–59) |
ARoM for upper and general cervical rotation and cervical flexion | CVA was found to be significantly correlated with increased cervical flexion (Spearman r = 0.30) and general rotation RoM (r = 0.33), but no significant association was observed with upper cervical rotation RoM (r = 0.15). |
FHP, froward head posture; NHP, neutral head posture; ARoM, active range of motion; SVA, sagittal vertical axis; CVA, craniovertebral angle; UCE, upper cervical extensor; LCE, lower cervical extensor; UCF, upper cervical flexor; LCF, lower cervical flexor; RCP, rectus capitis posterior; OCS, oblique capitis superior; SCM, sternocleidomastoid; LCo, longus coli; UT, upper trapezius; Sca, splenius capitis; SSC, semispinalis capitis; SSCe, semispinalis cervicis.