Handgrip Strength Cutoff Points for Functional Independence and Wheelchair Ability in Men With Spinal Cord Injury

To determine optimal handgrip strength (HGS) cutoff points for greater functional independence and wheelchair skills in men with spinal cord injury (SCI), and to establish predictive equations for functional independence and wheelchair ability in men with SCI, based on demographic characteristics, HGS, and functionality.

In this cross-sectional study conducted at a rehabilitation hospital, 54 men with SCI were recruited and stratified into high and low paraplegia groups. All participants performed a maximum HGS test to determine cutoff points for the Spinal Cord Independence Measure (SCIM-III) and Adapted Manual Wheelchair Circuit (AMWC). The primary outcomes were the SCIM-III, AMWC, and HGS. Demographic characteristics obtained from participants' electronic medical records were the secondary outcomes, used as predictor variables of functional independence.

The SCIM-III scale, performance score, and 3-minute overground wheeling test presented significant regression equations (R = 0.45, R = 0.69, and R = 0.72). The HGS showed a cutoff point of 102.5 kilogram force (kgf) to achieve a score of 70 on the SCIM-III and a 3-minute overground wheeling distance of 270 m. The HGS cutoff point to obtain a performance score of 23.7 seconds was 93.0 kgf.

The HGS was a significant predictor for the SCIM-III score, AMWC performance score, and 3-minute overground wheeling test. Three significant predictive equations were established based on HGS. The cutoff points could be adopted as parameters for optimal functional independence and wheelchair skills.