Physiatrist, Clinical Professor University of British Columbia Vancouver, British Columbia, Canada
Objectives : Hip Flexion Assist Orthoses (HFAOs) can improve gait in people with multiple sclerosis (MS) who have hip flexor weakness, but standardized selection criteria and clinical guidelines are lacking. This study aimed to identify patient characteristics associated with successful HFAO use and to generate practical, evidence-informed recommendations for clinicians. It sought to determine which combinations of strength and tone predict continued regular device use, which factors contribute to discontinuation, and how these findings can support structured decision-making for orthosis prescription.
Design: A retrospective chart review of 54 ambulatory MS patients assessed for HFAO was conducted at a community physiatry clinic in British Columbia. Patients underwent standardized interdisciplinary evaluation by an experienced physiatrist and orthotist, including real-time gait trials with sample devices. Data extracted included Medical Research Council (MRC) strength scores, Modified Ashworth Scale (MAS) spasticity ratings, and qualitative analysis of discontinuation patterns. Statistical analysis employed Kruskal-Wallis testing with post-hoc comparisons to identify strength and spasticity thresholds associated with successful outcomes. The study received institutional ethics approval.
Results: Of 54 patients assessed, 48 were recommended an HFAO; 40 acquired one and 19 continued regular use (47% long-term adherence). Successful users demonstrated significantly lower spasticity compared to discontinuers (mean MAS 0.77 vs. 1.5, p< 0.011). With few exceptions, patient assessed for HFAO’s had hip flexion weakness of MRC 1-3 with knee extension strength ≥3. Discontinuation resulted primarily from pain/discomfort (38%) and device bulkiness (31%), while cost barriers prevented 75% of non-adopters from proceeding.
Conclusion: This study establishes an HFAO prescription framework for MS patients, with specific motor profile criteria that predict successful outcomes: hip flexion MRC 1-3, knee extension MRC ≥3, and spasticity MAS < 2. A comprehensive pre-prescription evaluation, goal setting, and patient-centered decision-making can help identify and address barriers to use, ultimately enhancing patient selection and reducing device abandonment.
