A computational study of forward head posture biomechanics.

Forward head posture (FHP) is a common postural deviation linked to musculoskeletal disorders and altered cervical spine biomechanics. This study used a validated finite element model (C0-T1, THUMS v4.2) to quantify the biomechanical effects of FHP, with validation against cadaveric data for sagittal balance and range of motion in flexion-extension, axial rotation, and lateral bending. Sagittal balance parameters, including craniovertebral angle (CVA), occipital protuberance to C2 (OP-C2), cervical lordosis (C1-C2 and C2-C7), greater occipital nerve (GON), and C2 nerve root (C2-NR), were measured before and after a 2.5 cm anterior head displacement. FHP increased upper cervical lordosis and decreased lower cervical curvature, accompanied by measurable narrowing of neural foraminal spaces (GON and C2-NR) and elevated cortical bone stresses, particularly between C2-C3. These changes reflect compensatory adaptations that may predispose to pain and degeneration, underscoring the need for early intervention strategies to mitigate long-term spinal health impacts.