Comparison of the compression release and ischial containment transfemoral prosthetic socket designs using gait analysis : a pilot study

  • Mohammed Mustafa Kamil Mustafa Kamil

Student thesis: Master's Thesis

Abstract

Traditional transfemoral prosthetic socket designs share many challenges. Prosthetic sockets enclose the residual limb and connect to other parts of the prosthesis to facilitate control and promote a more natural gait pattern by the user. One of the main challenges is to create stability between the residual femur and the prosthetic socket, thus improving efficiency and comfort whilst reducing gait deviations.Established designs such as the ischial containment socket (ICS); purport to reduce femoral abduction by containing the medial aspect of the ischium in counterforce to the greater trochanter and femoral shaft. This design relies on a proximal ‘bony lock’ to limit femoral abduction at mid stance within the prosthesis. A new design of socket named the compression/release socket (CRS), however, uses three or more ‘compression’ regions between the femoral bone and the socket walls to minimise femoral motion. The CRS design claims to improve the gait pattern of the user through enhanced distal femoral stability and socket control. Despite minimal evidence being available, the design is currently being introduced in clinics worldwide.The aim of this research is to compare the stabilisation achieved in two transfemoral prosthetic socket designs by identifying and measuring the effect on the user using appropriate gait parameters. Initially, a literature review was conducted to establish understanding of normal and prosthetic gait. Literature was then examined to establish historical prosthetic transfemoral socket concepts and the biomechanics underpinning currently accepted designs. Due to the difficulty in obtaining participants appropriately fitted with the CRS sockets, this project has been presented as a feasibility study. Two designs of sockets were then compared: ICS versus CRS design. The gait of one subject with transfemoral amputation was assessed whilst wearing both sockets in a gait laboratory. Important kinematic and spatial temporal parameters, identified in the literature review, were compared for both socket designs under a variety of challenging walking conditions (level, downhill, uphill and cross slope walking). Comparison was also made between the amputated and contralateral side for each socket design. Results indicate that, kinematic parameters did not demonstrate large variations, but that some variation was found between prostheses when measuring hip abduction, hip flexion, knee flexion and ankle plantar flexion in both the prosthetic and contralateral limbs. When using the CRS design, user range of motion for the hip joint appeared to be greater than that of the ICS. Step length and step width on both sides were closely matched in both socket designs. Preliminary study results indicate that alteration in the step length or width did not reduce the velocity of gait, but was more likely to result from change of strategy by the participant to ensure greater control over balance or stability. Further research with a greater number of participants is required to investigate the effect of socket design on stability and gait parameters in the future.
Date of Award17 Dec 2015
Original languageEnglish
Awarding Institution
  • University Of Strathclyde

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