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Correlations between reach, lean and ladder tipping risk.

Christopher L Deschler1, Erika M Pliner2, Daina L Sturnieks3

  • 1Department of Bioengineering, University of Pittsburgh, 301 Schenley Place, 4420 Bayard St, Pittsburgh, PA 15213, United States.

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Summary

Overreaching on ladders increases fall risk for older adults. Trunk lean significantly impacts the center of pressure (COP), indicating a higher risk of ladder tipping. Understanding these factors can help prevent falls.

Keywords:
And fallsBalanceLadder fallsReachingSlipsTrips

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Area of Science:

  • Biomechanics
  • Gerontology
  • Occupational Safety

Background:

  • Ladder falls are a significant safety concern, particularly for older adults in home environments.
  • Overreaching is a primary behavior contributing to ladder instability and subsequent falls.
  • Quantifying the relationship between reaching, leaning, and center of pressure (COP) is crucial for assessing ladder tipping risk.

Purpose of the Study:

  • To investigate the correlations between maximum reach, trunk lean, and COP during ladder use in older adults.
  • To improve the assessment of ladder tipping risk associated with overreaching behaviors.
  • To establish thresholds for unsafe reaching and leaning to reduce ladder falls.

Main Methods:

  • 104 older adults performed a simulated roof gutter clearing task on a straight ladder.
  • Measurements included maximum reach (hand position), trunk lean angle, and COP during the task.
  • Statistical analyses, including correlation and regression, were used to examine relationships between variables.

Main Results:

  • COP showed a strong positive correlation with both maximum reach (r=0.74) and trunk lean (r=0.85).
  • Maximum reach and trunk lean were also highly correlated (r=0.89).
  • Trunk lean had a stronger influence on COP than maximum reach, highlighting its importance in ladder stability.

Conclusions:

  • Trunk lean is a critical factor in determining ladder tipping risk, more so than reach distance alone.
  • Estimated thresholds for unsafe reaching (113 cm) and leaning (29 cm) from the ladder midline were identified.
  • Findings can inform the development of safety guidelines and interventions to prevent ladder falls in older adults.