Successful First Gait of a Child With Hip-Disarticulation Prosthesis

Hip Disarticulation in Wound Care: A Case Series

BACKGROUND

Hip disarticulation (HD) is a radical lower extremity amputation performed by carefully transecting all muscles and nerves surrounding the hip joint and separating the leg at the joint capsule. It is considered a last resort to be used as a life-preserving measure under emergent circumstances due to high rates of morbidity and mortality.

METHODS

This case series presents 4 patients who underwent HD. The procedure was performed due to various indications including necrotizing fasciitis, gangrene, stump necrosis from previous above-the-knee amputation, and septic joint secondary to chronic osteomyelitis, 3 of which were planned and 1 was emergent.

RESULTS

The procedure was performed successfully in all 4 patients. Furthermore, all patients were eventually discharged to home or to a long-term care facility for wound care or rehabilitation.

CONCLUSIONS

Overall, HD should be reserved as a life-saving treatment for various indications including infections that fail other modalities, limb ischemia, trauma, and malignancy. Ideally, this procedure would be planned and performed on proper candidates; however, HD should still be a consideration in the emergent setting regardless of most optimal patients due to its life-saving potential.

Design and optimization of a hip disarticulation prosthesis using the remote center of motion mechanism

BACKGROUND

Hip disarticulation prostheses (HDPs) are not routinely seen in clinical practice, and traditional hip prostheses rotate around an axis at the front side of the pelvic socket.

OBJECTIVE

This study proposes a mechanism to restore the rotation center to the acetabulum of the amputated side and uses comparative experiments with traditional HDP to verify the validity of the novel design.

METHODS

A double parallelogram design of HDP based on a remote center of motion (RCM) mechanism was presented in this paper. Optimization was achieved by a genetic algorithm with the maximal integral size and minimal driving force of the mechanism.

RESULTS

The prototype was developed by final optimal results and tested by a hip disarticulated amputee. Testing results revealed that the RCM-HDP improved the range of motion of the hip prosthesis by 78%. The maximal flexion of the assorted prosthetic knee was closer to the sound side than a traditional HDP by 15%.

CONCLUSION

The proposed RCM-HDP promoted the kinematic performance and symmetry of the hip prosthesis compared to the traditional design.