Lower limb prosthetic interfaces

Abstract

The human–prosthesis interface is one of the most complicated challenges facing the field of prosthetics, despite substantive investments in research and development by researchers and clinicians around the world. The journal of the International Society for Prosthetics and Orthotics, Prosthetics and Orthotics International, has contributed substantively to the growing body of knowledge on this topic. In celebrating the 50th anniversary of the International Society for Prosthetics and Orthotics, this narrative review aims to explore how human–prosthesis interfaces have changed over the last five decades; how research has contributed to an understanding of interface mechanics; how clinical practice has been informed as a result; and what might be potential future directions. Studies reporting on comparison, design, manufacturing and evaluation of lower limb prosthetic sockets, and osseointegration were considered. This review demonstrates that, over the last 50 years, clinical research has improved our understanding of socket designs and their effects; however, high-quality research is still needed. In particular, there have been advances in the development of volume and thermal control mechanisms with a few designs having the potential for clinical application. Similarly, advances in sensing technology, soft tissue quantification techniques, computing technology, and additive manufacturing are moving towards enabling automated, data-driven manufacturing of sockets. In people who are unable to use a prosthetic socket, osseointegration provides a functional solution not available 50 years ago. Furthermore, osseointegration has the potential to facilitate neuromuscular integration. Despite these advances, further improvement in mechanical features of implants, and infection control and prevention are needed.

A Scoping Review of Pressure Measurements in Prosthetic Sockets of Transfemoral Amputees during Ambulation: Key Considerations for Sensor Design

“…To address this issue, adjustable sockets have been developed in the field with both smart and manually controlled systems [9,14,22,[25][26][27]. Pressure-whether qualitative or quantitative-is often the prescribed scale against which adjustable socket volumes are altered.…”

“…Unfortunately, rehabilitation is especially difficult for transfemoral amputees, and research indicates that a high amputation level is associated with both prosthetic non-use and a decreased probability of remaining ambulatory [ 2 , 3 ]. Socket fit has been cited as one of the main factors affecting gait re-education, rehabilitation, and quality of life for amputees from the viewpoint of both amputees and clinicians [ 4 , 5 , 6 , 7 , 8 , 9 ]. Poor socket fit is the cause of at least one gait deviation, in people with lower limb amputation, which could be linked to premature long-term musculoskeletal degenerations [ 6 , 10 , 11 ].…”

“…In line with traditional socket design theory, the adjustable socket adapts to equally distribute pressure across the residual limb, or relieves pressure from sensitive regions by exerting more pressure through more tolerant regions [ 14 , 23 , 27 , 28 , 29 ]. Furthermore, continuous socket volume adjustments have been shown to promote residual limb volume management [ 9 ]. More generally, continuous monitoring, such as pressure and temperature at the stump–socket interface, can provide immediate feedback on socket fit [ 4 ], which would enable more informed and timely intervention prescriptions by clinicians [ 30 , 31 ].…”

“…Many of the previously mentioned research developments for lower limb prosthetics were solely tested with transtibial amputees [ 4 , 10 , 11 , 23 , 50 ]. Several review articles on lower limb socket technology do not explicitly discriminate their findings against transfemoral or transtibial prostheses, but all instances cited more articles whose titles referred to the terms transtibial or below-knee compared with the terms transfemoral or above-knee, with a roughly 2.4 times higher prevalence on average [ 9 , 15 , 32 , 36 , 57 ]. This is further emphasized by another review article that analyzed interface stress measurements in transtibial sockets only [ 38 ], but similar analyses have not been published for transfemoral amputees; thus, the data for transfemoral amputees are very limited [ 15 ].…”

The Hybrid Subischial Socket for Persons With Transfemoral Amputation: Gait Parameters and Clinical Assessment of a Case Series

“…Five trials were recorded, during which at least one gait cycle could be identified using the force plate data. Focusing on a full gait cycle for each leg, based on both kinematics and kinetics measurements and the identification of the heel strike and toe-off events, the mean value of the following parameters was calculated: 21, 22 1) Walking speed (m/s), 2) Cadence (steps/min), 3) Step width (m), 4) Stride length (m), 5) Double support (%), 6) Hip extension (degrees). 23 For a subset of the above mentioned gait analysis parameters, the DoA was also calculated: Hip angles on the sagittal plane of both legs were exported in MATLAB.…”