IDEO energy-storing orthosis: Effects on lower extremity function and preservation.

INTRODUCTION: The Intrepid Dynamic Exoskeletal Orthosis (IDEO) brace is a custom energy-storing orthosis design meant to improve gait, stability, and function after lower extremity injury or limb salvage. Early studies demonstrated the potential for the IDEO to improve functional performance, in conjunction with its paired return to run (RTR) rehabilitation program, compared to other brace types, and an impressively decreased rate of late amputation. The current study aimed to investigate these functional and revision outcomes from our institution to determine which patients may benefit most from IDEO bracing and what factors of the IDEO design and rehabilitation program are most important for improved outcomes after lower extremity trauma and/or loss of function.

METHODS: We performed a retrospective review of all patients treated with a IDEO style brace at a single military lower extremity trauma referral center between May 2003 and November 2017. We reviewed the medical records for initial diagnosis, post-orthotic rehabilitation program, IDEO use characteristics, pain, change in desire for amputation, and whether patient underwent eventual amputation.

RESULTS: We identified 213 patients with 222 lower extremities treated with IDEO brace. Of these, 76 limbs were treated for combat-related injuries. At one year follow-up, use status could not be determined for 37 extremities (16.7%). Of the 185 limbs with use data available, 116 (61.1%) continued regular brace use, and 37 (15.7%) reported intermittent use. Patients diagnosed with footdrop or weakness were more likely to continue use (OR 2.33, p=0.04), while patients with a previous fusion were less likely to continue use (OR 0.45, p=0.049). Undergoing any dedicated therapy increased chances of continued use (OR 3.37, p<0.001). At final follow-up, 16 patients (7.5%) underwent delayed lower extremity amputations following IDEO treatment. Overall, 27.2% of patients who initially desired amputation eventually underwent amputation despite IDEO brace use. Patients who underwent amputation reported higher pain levels (2 versus 5, p<0.001).

DISCUSSION: In select patients, the IDEO may decrease the desire for delayed amputation and permit higher levels of activity; however, its efficacy appears tied to the rehabilitative regimen, pain levels, and initial diagnosis. These findings should guide post-surgical extremity bracing prescriptions and expectations.