[Influence of spinal orthosis on gait and physical functioning in women with postmenopausal osteoporosis]

Osteoporosis is a widespread chronic bone disease leading to an increased risk of bone fractures. The most common clinical consequences are back pain, hyperkyphosis, limitations of physical functioning and activities of daily living as well as reduced quality of life. Furthermore, osteoporosis is associated with decreased strength and deficits of gait and balance, all together resulting in an increased risk of falls and a subsequent aggravation of fracture risk. Besides pharmaceutical and exercise therapy, back orthoses are increasingly being used in the therapy of osteoporosis and rehabilitation after vertebral fractures. Previous studies have shown that wearing a spinal orthosis results in a reduction of pain as well as improvements of posture and back extensor strength. To date there is no study that has evaluated the effects of a spinal orthosis on gait stability and physical functioning in patients with osteoporosis. Therefore the purpose of the present study was to assess the effects of a spinal orthosis on gait and pain-induced limitations of activities of daily living (ADL) in women with osteoporosis.

A total of 69 postmenopausal osteoporotic women with and without vertebral fractures were randomly assigned to receive either a spinal orthosis (Thämert Osteo-med intervention group n=35; average age 74 ± 8.3 years, height 158.3 ± 6.3 cm, weight 62.8 ± 9.6 kg, t-score -2.6  ± 1.0, number of vertebral fractures 1.4 ± 2.0) or to a waiting list control group (n= 34, age 74.1 ± 7.7 years, height 159.6 ± 5.9 cm, weight 65.4 ± 11.3 kg, t-score -2.9± 0.8, number of vertebral fractures: 0.9 ± 1.2). The following outcome measures were collected at baseline and at 3 and 6 months follow-up: gait parameters including gait analysis: velocity, stride length and width, double support time (% of gait cycle) and perceived limitations in activities of daily living (numeric rating scale 1-10; 1=best, 10= worst situation).

The ANCOVA indicated a significant reduction of the double support time at 6 months in the intervention group (p < 0.05) without a significant influence of the covariate vertebral fractures status. The other parameters remained unchanged (p > 0 .05). Regarding the pain-related ADL limitations there were significant differences in the amount of change over the study period depending on the baseline value. Stratified into terciles (≤ 2.5; 2.6-5.0; >5) patients with initially high values showed a significantly greater reduction in perceived ADL restrictions compared to patients in the lowest tercile (-2.7 ± 2.7 versus 1.5 ± 2.1).

The study demonstrated that wearing a spinal orthosis introduced a reduction in double support time associated with a beneficial impact on gait stability. Furthermore, there was a positive effect on pain-related restrictions of ADL evident in women with a high level of limitations at baseline. Besides previously shown reductions in pain, improvements in back extensor strength and correction of posture, the application of a spinal orthosis may induce advantages for gait stability and physical functioning in women with postmenopausal osteoporosis. Future studies should consider a longer follow-up to evaluate possible effects on the risk of falling and fractures.