The effects of domestic mechanical knee joints on pelvic motion in transfemoral amputees

Abstract

Purpose Pelvic asymmetry in the sagittal and horizontal planes among prosthesis users is related to the strength of the abdominal and back muscles. Considering that lumbosacral pathologies and pain in long-term transfemoral prosthesis users can cause asymmetric pelvic motion, it is necessary to investigate pelvic asymmetry caused by prosthetic components. The aim was to compare the gait symmetry of the pelvis of active transfemoral amputees using different types of prosthetic knee joints (Non-microprocessor-controlled prostheses (NMCPs) and microprocessor-controlled prostheses (MCP) knees). Methods The two patient groups comprised eight transfemoral amputees: four patients had NMCP joints (Turkish products), and four patients had MCP knees. The reference group consisted of ten normal volunteers. In this work, the 3-D motion of the pelvis, hip, knee and ankle was assessed using the VICON system. Results The results revealed that during stance, the kinematics of pelvic movement in the amputee group differed from those of the control group in terms of the total excursion anterior pelvic tilt (APT) and maximum and minimum degrees of APT (p < .05). We evaluated the graphics of the NMCP and MCP knee joints and found that the prosthesis-side APT was closer to that of the control group during the stance phase among the NMCP users, while the APT of the MCP users was closer to that of the control group during the swing phase. Conclusion The investigated MCP benefitted the patients considerably. The NMCP did not provide as much walking as the MCP but produced less APT. Implications for Rehabilitation The MCP may not provide symmetrical pelvic motion during all phases of the gait cycle. In transfemoral amputees using MCP, focusing on pelvis in walking training will contribute to pre-prosthetic and post-prosthetics rehabilitation. The NMCP knee joint may be closer in terms of APT.