Custom Dynamic Orthoses and Physical Therapist Intervention for Bilateral Midfoot Amputation: A Case Report.

OBJECTIVE: Partial foot amputation is often associated with decreased mobility and function. Recent advances in custom carbon-fiber dynamic ankle-foot orthoses (CDOs) have improved gait, pain, and function following musculoskeletal trauma and can benefit individuals with partial foot amputation. However, limited information is available related to CDO use outside the military. The purpose of this case report is to describe the course of care and outcomes of a civilian provided with CDOs after bilateral transmetatarsal amputation. CASE DESCRIPTION: A 72-year-old man had a blood-borne bacterial infection (septicemia) of unknown origin at 68 years of age, developed limb-threatening necrosis of the hands and feet, and received bilateral transmetatarsal amputations with skin grafting. The patient initially used foam toe fillers and cushioned shoes but was functionally limited and experienced recurrent ulceration. He was fitted with bilateral CDOs 39 months after amputation and completed device-specific training with a physical therapist. RESULTS: After 1 week with the CDOs, ankle range of motion during gait was reduced, but greater than 40% increases were observed in bilateral ankle plantarflexor moments and ankle plantarflexion push-off power compared with the toe fillers. With additional therapist-directed training focused on gait and activity performance, ankle plantarflexor moments and plantarflexion push-off power further increased when compared with results after 1 week of CDO use. The patient reported marked improvement in quality of life with the CDOs due to improved walking ability on level and uneven terrain, marked improvement in confidence, and reduced pain. CONCLUSION: This case reflects the lessons learned and outcomes of a civilian using bilateral CDOs after bilateral transmetatarsal amputation and with poor skin quality. The results from this case study suggest that carbon-fiber CDOs and focused training by a physical therapist can result in improved gait biomechanics, mobility, and quality of life.

On the exponent in the power law for the attenuation at low frequencies in sandy sediments.

Shallow water transmission loss measurements yield intrinsic attenuation estimates for acoustic waves in the underlying sediment, with results that are consistent with attenuation being proportional to frequency raised to a power n, with n between 1.6 and 1.87. Plausible theory suggests that n should be identically 2. The discrepancy can be explained because the inverse analysis inferences were made with the neglect of an additional attenuation mechanism where generated lower velocity shear waves carry energy downwards out of the waveguide. The shear wave effect has a weaker dependence on frequency than the intrinsic attenuation, so the apparent exponent is shifted downward.