Comparative Effect of Orthosis Design on Functional Performance

Abstract

Background: High-energy extremity trauma is common in combat. Orthotic options for patients whose lower extremities have been salvaged are limited. A custom energy-storing ankle-foot orthosis, the Intrepid Dynamic Exoskeletal Orthosis (IDEO), was created and used with high-intensity rehabilitation as part of the Return to Run clinical pathway. We hypothesized that the IDEO would improve functional performance compared with a non-custom carbon fiber orthosis (BlueRocker), a posterior leaf spring orthosis, and no brace. Methods: Eighteen subjects with unilateral dorsiflexion and/or plantar flexion weakness were evaluated with six functional tests while they were wearing the IDEO, BlueRocker, posterior leaf spring, or no brace. The brace order was randomized, and five trials were completed for each of the functional measures, which included a four-square step test, a sit-to-stand five times test, tests of self-selected walking velocity over level and rocky terrain, and a timed stair ascent. They also completed one trial of a forty-yard (37-m) dash, filled out a satisfaction questionnaire, and indicated whether they had ever considered an amputation and, if so, whether they still intended to proceed with it. Results: Performance was significantly better with the IDEO with respect to all functional measures compared with all other bracing conditions (p < 0.004), with the exception of the sit-to-stand five times test, in which there was a significant improvement only as compared with the BlueRocker (p = 0.014). The forty-yard dash improved by approximately 35% over the values for the posterior leaf spring and no-brace conditions, and by 28% over the BlueRocker. The BlueRocker demonstrated a significant improvement in the forty-yard dash compared with no brace (p = 0.033), and a significant improvement in selfselected walking velocity on level terrain compared with no brace and the posterior leaf spring orthosis (p < 0.028). However, no significant difference was found among the posterior leaf spring, BlueRocker, and no-brace conditions with respect to any other functional measure. Thirteen patients initially considered amputation, but after completion of the clinical pathway, eight desired limb salvage, two were undecided, and three still desired amputation. Conclusions: Use of the IDEO significantly improves performance on validated tests of agility, power, and speed. The majority of subjects initially considering amputation favored limb salvage after this noninvasive intervention.

Can an Integrated Orthotic and Rehabilitation Program Decrease Pain and Improve Function After Lower Extremity Trauma?

“…We did not have a control group that completed only physical therapy without the use of the IDEO for 8 weeks. A previous study at this institution found the IDEO improved patients' physical performance on specific tasks more than two other commercially available ankle-foot orthoses and no brace [18]. Given the apparent clinical success of the Return to Run clinical pathway with the IDEO in returning patients to duty [1], the limited improvements with rehabilitation alone, as demonstrated by the lack of significant improvement in the first 4 weeks of this study when the IDEO was not worn, and we believe this issue had already been addressed by our prior study [18], we believe it would have been inappropriate to randomize the patients to rehabilitation with and without the IDEO.…”

“…1). The IDEO has been shown in a small cohort of patients undergoing limb salvage to result in better functional performance and to decrease the number of patients undergoing limb salvage who were considering amputation [18]. However, this study occurred at a single time point and data on validated, patient-reported outcomes were not collected.…”

How Does Ankle-foot Orthosis Stiffness Affect Gait in Patients With Lower Limb Salvage?

“…Use of a semi-rigid, dynamic AFO inherently reduced the ROM and power capabilities at the ankle relative to controls and compensations at more proximal joints such as the knee resulted. Although none of the stiffness conditions restored all biomechanical gait parameters to those of control subjects, self-selected walking velocity was restored and previous reports have shown greater performance benefits with the IDEO compared with commercially available designs [33]. For walking, if a range of dynamic AFO stiffnesses may be appropriately prescribed, this may reduce the burden on the orthotist to experimentally test numerous designs to find the best stiffness characteristics for individual patients.…”

“…Patzkowski et al [33] was the first to compare three different dynamic AFOs during performance tasks in military patients with limb salvage. These AFOs were the posterior leaf spring, Blue Rocker (Allard USA Inc, Rockaway, NJ, USA), and a new custom dynamic AFO available to wounded warriors called the Intrepid Dynamic Exoskeletal Orthosis (IDEO, patent pending #20120271214).…”

Rehabilitation of Lower Extremity Trauma: a Review of Principles and Military Perspective on Future Directions

“…Patzkowski et al [105] attributes the high functional loss in limb salvage patients to muscle loss, nerve injury, and pain, and indicated the need for development of better orthoses given the high rate of delayed elective amputations. In a study of these patients using the Intrepid Dynamic Exoskeletal Orthosis (IDEO) brace (shown in Fig.…”