The standard posture is a myth: a scoping review.

Area of Science:

• Biomechanics
• Kinesiology
• Human Posture Analysis

Background:

• The Kendall's manual posture standard is a common reference for postural assessment.
• Its historical origins and supporting evidence have not been previously documented.
• This lack of evidence raises questions about its validity in clinical practice.

Purpose of the Study:

• To investigate the original source and design methodology of the Kendall's manual posture.
• To compare the described posture with current scientific literature on human alignment.
• To evaluate the scientific basis of using this standard for postural evaluation.

Main Methods:

• A scoping review following PRISMA Extension guidelines was conducted.
• Searches were performed in PubMed and Scopus using keywords: "standing posture," "plum line," and "gravity line."
• Included were publications in English, French, German, or Spanish concerning adult posture without pathology.

Main Results:

• Six articles and three books were analyzed, revealing the posture's origin in early 19th-century work.
• The original work aimed for unsupported static standing, contained anatomical misconceptions, and is unrealistic.
• Kendall's "ideal alignment" does not align with the actual line of gravity or natural postural variations.

Conclusions:

• The use of Kendall's standard for postural assessment is not supported by current scientific evidence.
• This standard may lead to a high rate of false positives in identifying postural deficiencies.
• Particular caution is advised when applying this standard to elderly populations due to potential inaccuracies.