The aim of the study is to investigate the effect of forward head posture on knee joint proprioception and to investigate the effect of forward head posture on balance.

Forward head posture (FHP) represents a prevalent sagittal plane deviation characterized by the anterior displacement of the head relative to the shoulder. While its impact on cervical proprioception and upper-body neuromuscular control is well-documented, current literature reveals significant gaps regarding its influence on distal joint function. This study aims to investigate the musculoskeletal system as a holistic kinetic chain, wherein cervical misalignment may necessitate compensatory adaptations throughout the body to maintain the center of gravity. Research indicates that FHP is frequently associated with an anterior pelvic tilt and altered ankle joint position errors, suggesting that postural deviations in the neck can diminish neuromuscular performance in the lower extremities. Given this interconnected nature, it is hypothesized that FHP similarly affects knee joint proprioception and stability. By evaluating these distal effects, this investigation seeks to clarify whether cervical postural deviations contribute to balance impairments or knee instability. The findings may have significant implications for clinical practice, potentially shifting rehabilitation paradigms to include cervical assessment and correction when treating patients with lower-limb injuries or chronic knee instability.

Inclusion Criteria:

1. Ages range from 18-35years old
2. Participants are categorized as having FHP, the craniovertebral angle (CVA) measurement is used, FHP was classified as having a CVA < 53°; thus, participants were in the FHP group when CVA was <53°. Conversely, the control group was defined as having normal or no FHP when a participant's CVA was >53°.

Exclusion Criteria:

• Subjects will be excluded if they have:

  1. Fractures
  2. Neck pain
  3. Deformity of the spine or extremities
  4. A history of significant knee injury requiring medical treatment in the past 12 months
  5. Any inflammatory joint disease
  6. Primary Musculo-skeletal surgical interventions

A head position that is overly anterior in relation to the shoulder is common in people with FHP. This postural deviation is linked to neck pain, vestibular deficits, impaired proprioception, aberrant muscle activation, and changed breathing patterns