Objective: To compare gait parameters analyzed with instrumented treadmill gait analysis system in urban elderly who had hypovitaminosis D with a group of healthy normal serum vitamin D.
Materials and Methods: This prospective study on urban community-dwellers adults aged 65 to 85 years who attended
Physical Medicine and Rehabilitation out-patient clinic in our hospital between January 2015 and December 2015. Demographic data including history of falls within the past 12 months were collected. Serum 25-hydroxyvitamin D [25OHD] was measured. Gait analysis, particularly temporospatial gait parameters, was evaluated with instrumented treadmill system (Zebris). The participants were divided into 3 groups as normal serum 25OHD level (>30 ng/ml) or hypovitaminosis D including insufficient (20 to 30 ng/ml) and deficient (<20 ng/ml).
Results: Among 114 enrolled participants, 86 completed the study. The study found 39.5% had normal serum 25 OHD,
41.9% had insufficient and 18.6% had deficient level. Age and body mass index [BMI] were comparable among the 3 groups.
The participants with hypovitaminosis D tended to have longer double-limb support than those who had normal serum OHD levels. Other temporospatial gait parameters were not different among groups. Participants with the history of falls in
previous 12 months (46.5%) had significantly wider step width which was interpreted as less gait stability than those
without previous falls (p = 0.026).
Conclusion: Hypovitaminosis D tended to affect temporospatial gait parameter particularly double-limb support phase. History of falls was significantly associated with wider step width and less stability. The instrumented treadmill gait analysis system should be used in clinical practice especially in individuals with a tendency to fall.

Keywords: Hypovitaminosis D, Gait analysis, Gait impairments