Sit-to-Stand Navicular Drop Test-Based Injury Risk Zones Derived from a U-Shaped Relationship in Male University...

Area of Science:

• Biomechanics
• Sports Medicine
• Orthopedics

Background:

• Foot mobility is a key intrinsic risk factor for lower-limb injuries.
• Current pronation/supination classifications use arbitrary cut-points, limiting precision.
• A continuous, data-driven approach is needed to better quantify injury risk.

Purpose of the Study:

• To develop a data-driven framework for characterizing a continuous sit-to-stand navicular drop test (SSNDT) and injury risk gradient.
• To derive clinically interpretable relative-risk bands for practical injury risk zones.
• To establish a more precise method for assessing foot mobility-related injury risk.

Main Methods:

• Analyzed data from 137 physically active male students (274 feet).
• Assessed intra-rater reliability of the SSNDT using ICC(3,1).
• Employed a quadratic mixed-effects logistic regression model to link SSNDT and injury risk, deriving odds-ratio-based risk bands.

Main Results:

• SSNDT demonstrated good intra-rater reliability (ICC(3,1) = 0.82).
• A non-linear, U-shaped association between SSNDT and injury risk was identified, with minimum risk around 5.5 mm.
• Derived risk bands showed increasing injury prevalence from 4.2% (Safe) to 52.4% (Extreme).

Conclusions:

• The SSNDT provides a robust, data-driven basis for quantifying foot mobility and injury risk on a continuous gradient.
• The derived risk bands offer clinically interpretable zones, avoiding arbitrary cut-points.
• This framework supports individualized risk screening for lower-limb injuries.