Comparison of the Power Knee and C-Leg during step-up and sit-to-stand tasks.

For U.S. military service members with transfemoral amputations there are different prosthetic knee systems available that function differently. For example the C-Leg(®) (C-Leg, Otto Bock Healthcare, GmbH, Duderstadt, Germany) is a passive microprocessor knee, and the Power Knee™ (PK, Ossur, Reykjavík, Iceland) provides active positive power generation at the knee joint. This study examined both step-up and sit-to-stand tasks performed by service members using C-Leg and PK systems to determine if the addition of positive power generation to a prosthetic knee can improve symmetry and reduce impact to the remaining joints. For both tasks, average peak sagittal knee powers and vertical ground reaction forces (GRFs) were greater for the intact limb versus the amputated limb across PK and C-Leg groups. For the sit-to-stand task, peak knee power of the amputated limb was greater for PK users versus C-Leg users. Vertical GRFs of the intact limb were greater for the C-Leg versus the PK. The performance of the PK relative to the C-Leg during a STS task illustrated few differences between components and no effect on the intact limb.

Assessment of transfemoral amputees using C-Leg and Power Knee for ascending and descending inclines and steps.

Adding active power to a prosthetic knee unit may improve function and reduce the potential for overuse injuries in persons with transfemoral amputation (TFA). Servicemembers who have sustained a TFA are often young and motivated to perform at high functional levels. The goal of this article is to compare the biomechanics of ramp and stair descent and ascent for participants using the C-Leg and the Power Knee (PK). Subjects were asked to ascend and descend an instrumented staircase and 12 degree ramp at their comfortable pace while equipped with retroreflective markers. Temporal-spatial and kinetic data were collected. Knee power generated by the nondisabled limb during stair ascent for subjects wearing the C-Leg was significantly greater than for those wearing the PK. Knee power generated by prosthetic knee units was significantly greater for subjects while wearing the PK. Although the PK reduced the power required from the nondisabled knee during stair climbing, it does not appear to be superior to the C-Leg for other tasks. Adding power to a prosthetic knee may reduce wear on the nondisabled limb; however, there are still limitations that require improvement.

The contribution of sympathetic mechanisms to postamputation phantom and residual limb pain: a pilot study.

UNLABELLED: Postamputation pain (PAP) affects over 60% of major limb amputees. One of the main challenges in treating PAP is the difficulty involved in identifying pain mechanism(s), which pertains to both residual limb pain (RLP) and phantom limb pain (PLP). In this study, sympathetic blocks were performed on 17 major limb amputees refractory to treatment, including 2 placebo-controlled blocks done for bilateral amputations. One hour postinjection, mean RLP scores at rest declined from 5.2 (SD 2.8) to 2.8 (SD 2.6) (P = .0002), and PLP decreased from 5.3 (SD 3.1) to 2.3 (SD 2.1) (P = .0009). By 1 week, mean pain scores for RLP and PLP were 4.3 (SD 2.9) and 4.2 (SD 3.0), respectively. Overall, 8 of 16 (50%) patients experienced ≥50% reduction in RLP 1-hour postinjection, with the beneficial effects being maintained at 1 and 8 weeks in 4 and 1 patient(s), respectively. For PLP, 8 of 15 (53%) patients obtained ≥50% decrease in pain 1-hour postblock, with these numbers decreasing to 2 patients at both 1 and 8 weeks. In the 2 bilateral amputees who received controlled injections, mean PLP and RLP at rest scores went from 4.0 and 3.3 to 4.0 and 2.5 1-hour postblock, respectively, on the placebo side. On the treatment side, mean PLP and RLP scores decreased from 7.5 and 6.5, respectively, to 0. PERSPECTIVE: The results of this study suggest that sympathetic mechanisms play a role in PLP and to a lesser extent, RLP, but that blocks confer long-term benefits in only a small percentage of patients.

Servicemembers and veterans with major traumatic limb loss from Vietnam war and OIF/OEF conflicts: survey methods, participants, and summary findings.

Care of veterans and servicemembers with major traumatic limb loss from combat theaters is one of the highest priorities of the Department of Veteran Affairs. We achieved a 62% response rate in our Survey for Prosthetic Use from 298 Vietnam war veterans and 283 servicemembers/veterans from Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) who sustained major traumatic limb loss. Participants reported their combat injuries; health status; quality of life; and prosthetic device use, function, rejection, and satisfaction. Despite the serious injuries experienced, health status was rated excellent, very good, or good by 70.7% of Vietnam war and 85.5% of OIF/OEF survey participants. However, many health issues persist for Vietnam war and OIF/OEF survey participants (respectively): phantom limb pain (72.2%/76.0%), chronic back pain (36.2%/42.1%), residual-limb pain (48.3%/62.9%), prosthesis-related skin problems (51.0%/58.0%), hearing loss (47.0%/47.0%), traumatic brain injury (3.4%/33.9%), depression (24.5%/24.0%), and posttraumatic stress disorder (37.6%/58.7%). Prosthetic devices are currently used by 78.2% of Vietnam war and 90.5% of OIF/OEF survey participants to improve function and mobility. On average, the annual rate for prosthetic device receipt is 10.7-fold higher for OIF/OEF than for Vietnam war survey participants. Findings from this cross-conflict survey identify many strengths in prosthetic rehabilitation for those with limb loss and several areas for future attention.

Unilateral lower-limb loss: prosthetic device use and functional outcomes in servicemembers from Vietnam war and OIF/OEF conflicts.

Rehabilitation goals following major combat-associated limb loss in World War II and the Vietnam war focused on treatment of the injury and a return to civilian life. The goal for Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) servicemembers is to restore function to the greatest possible degree and, if they desire, return them to Active Duty, by providing them with extensive rehabilitation services and a variety of prosthetic devices. Our study determines the usefulness of these diverse types of prosthetic devices for restoring functional capability and documents prosthesis use and satisfaction. We compare servicemembers and veterans with major combat-associated unilateral lower-limb loss: 178 from the Vietnam war and 172 from OIF/OEF conflicts. Of survey participants with unilateral lower-limb loss, 84% of the Vietnam group and 94% of the OIF/OEF group currently use at least one prosthetic device. Reasons for rejection varied by type of device, but common reasons were pain, prosthesis too heavy, and poor fit. Abandonment is infrequent (11% Vietnam group, 4% OIF/OEF group). Future efforts should aim to improve prosthetic-device design, decrease pain, and improve quality of life for these veterans and servicemembers.

Prosthetic cost projections for servicemembers with major limb loss from Vietnam and OIF/OEF.

This study projects prosthetic- and assistive-device costs for veterans with limb loss from Vietnam and injured servicemembers returning from Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) to inform the Department of Veterans Affairs (VA) for these veterans' future care. The 2005 Medicare prosthetic device component prices were applied to current prosthetic and assistive-device use obtained from a national survey of 581 veterans and servicemembers with major traumatic amputations. Projections were made for 5-year, 10-year, 20-year, and lifetime costs based on eight Markov models. Average 5-year projected costs for prosthetic and assistive-device replacement for the Vietnam group are lower than for the OIF/OEF cohort due in part to use of fewer and less technologically advanced prosthetic devices and higher frequency of prosthetic abandonment. By limb-loss level, for the Vietnam group and OIF/OEF cohort, 5-year projected unilateral upper limb average costs are $31,129 and $117,440, unilateral lower limb costs are $82,251 and $228,665, and multiple limb costs are $130,890 and $453,696, respectively. These figures provide the VA with a funding estimate for technologically advanced prosthetic and assistive devices within the framework of ongoing rehabilitation for veterans with traumatic limb loss from the Vietnam and OIF/OEF conflicts.

Hospitalization experiences of U.S. servicemembers before, during, and after participation in peacekeeping operations in Bosnia-Herzegovina.

BACKGROUND: There are relationships among morbidity experiences before, during, and after participation in overseas military operations. METHODS: U.S. servicemembers who deployed to Bosnia-Herzegovina during a 4-year period were classified based on their last hospitalizations prior to deploying. Hospitalization rates during and following deployment were calculated in relation to the timing and causes of pre-deployment hospitalizations. RESULTS: Deployers ever hospitalized pre-deployment were 120% and 50% more likely to be hospitalized during and following deployment, respectively. For nearly every category of diagnoses, hospitalization rates during and following deployment were highest among those hospitalized for the same category, intermediate among those hospitalized for other categories, and lowest among those not hospitalized prior to deploying. Deployers hospitalized within 1 month, 2-3 months, or > 3 months of deploying were 3.8, 2.6, and 1.4-times more likely to be hospitalized during deployment. CONCLUSIONS: The nature and recency of prior hospitalizations significantly determine during and post-deployment hospitalization risks.