| Description |
Socket prosthetics are currently used to restore function to individuals with limb loss. However, there are several complications associated with these docking systems, especially in patients with limited residual limb lengths. Percutaneous, osseointegrated prosthetics are presently being investigated to overcome these problems. To help develop these prosthetics, an ovine model was used in which the right metacarpal III bone was surgically amputated and restored with an osseointegrated implant with an exoprosthetic. The purposes of this study were to develop a method to quantify and to compare limb function before and following amputation. A commercially available force sensitive mat (Tekscan HR Mat, Tekscan, Inc., Boston, MA) was used in conjunction with a custom oval walkway to measure the limb function from the ovine model. Limb loads, stride length, and stance phase as a percent gait cycle were collected from each limb before amputation and then compared to postamputation data. To date, 17 animals have been amputated and implanted with a percutaneous, osseointegrated implant and fit with an exoprosthetic. On average, the prosthetic was loaded 82.5% ± 5.3% (N=17) of the preamputation load 1 month after surgery and improved to 86.9% ± 9.9% (N=3) at 6 months following surgery. The kinematic data of the stance phase as a percent gait cycle and stride length of the amputated limb were not significantly different from the contralateral, nonamputated limb following the operation. Based upon these findings, it was concluded that the prosthetic limb of the animals was loaded by the subjects, albeit less than the preamputation loads. However, based upon the kinematic data obtained, the subjects were not limping. This method may help to establish a rehabilitation timeline for patients with percutaneous, osseointegrated implants with an exoprosthetic in the future and an objective method to compare new treatments for amputees. |
