The effect of transverse prosthetic alignment changes on socket reaction moments during gait in individuals with transtibial amputation

A systematic review of methods used to assist transtibial prosthetic alignment decision-making

Prosthetic alignment is a highly subjective process that is still based on clinical judgments. Thus, researchers have aimed their effort to quantify prosthetic alignment by providing an objective method that can assist and guide prosthetists in achieving transtibial (TT) prosthetic alignment. This systematic review aimed to examine the current literature on TT prosthetic alignment to scope the qualitative and quantitative methods designed to guide prosthetists throughout the TT prosthetic alignment process as well as evaluate the reported instruments and devices that are used to align TT prostheses and their clinical feasibility. A literature search, completed in June 2022, was performed using the following databases: Web of Science (Clarivate), SCOPUS (Elsevier), and Pub Med (Medline) with searching terms focusing on TT, prosthesis, prosthetist, prosthetic alignment, and questionnaires, resulting in 2790 studies being screened. Twenty-four studies have used quantitative methodologies, where sensor technologies were found to be the most frequently proposed technology combined with gait analysis tools and/or subjective assessments. A qualitative method that assists prosthetists throughout the alignment process was not found. In this systematic review, we presented diverse methods for guiding and assisting clinical decision-making regarding TT prosthetic alignment. However, most of these methods considered varied parameters, and there is a need for elaboration toward standardized methods, which would improve the prosthetic alignment clinical outcome.

A proper sequence of dynamic alignment in transtibial prosthesis: insight through socket reaction moments

Dynamic alignment in prosthetic fitting is important because it affects the user's stability, kinematics, and kinetics such as socket reaction moments. It is performed by tuning the spatial relationship between the transtibial prosthetic socket and the foot following sequential observational gait analysis in the three anatomical planes. However, the order of planes in which the adjustment should be performed is still unclear. To investigate the appropriate sequence of dynamic alignment adjustment, ten participants with transtibial amputation were asked to walk in different alignment conditions (flexion, extension, adduction, abduction; lateral, medial, anterior, and posterior translation of the socket, and plantarflexion, dorsiflexion, inversion, and eversion of the foot) to measure socket reaction moments in the out-of-planes (e.g., the effect of sagittal alignment on the coronal moment). A significant difference was found only among socket posterior translation, socket flexion, and baseline alignment in the coronal moment (P = 0.02). The results of the current and previous studies suggest that moments in the coronal plane are affected by alignment changes in all three planes, whereas moments in the sagittal plane are affected only by sagittal alignment changes. It is suggested that the procedure of alignment adjustments should be finalized in the coronal plane.

Angulation vs translation of transtibial prosthetic socket: their difference analyzed by socket reaction moments

BACKGROUND

Previous studies investigated the effects of alignment changes in transtibial prostheses on socket reaction moments. However, the effects of angular and translational alignment changes with equal displacement between the foot and the socket were not directly compared.

RESEARCH QUESTIONS

What are the different effects of angular and translational alignment changes in transtibial prostheses?

METHODS

Ten individuals with transtibial prostheses participated in the measurement of temporo-spatial parameters, socket reaction moments, and their timings under nine alignment conditions (3° flexion/extension, anterior/posterior translation, 6° adduction/abduction, medial/lateral translation, and baseline). The displacement of the prosthetic feet was set to be equal between the angular and translational changes.

RESULTS

No significant changes in walking speed were found. Similar effects were observed in the magnitudes, but not in timing, of the moments under angular and translational changes in the sagittal plane (p < 0.01 for the differences in peak extension moment among anterior translation, baseline, and extension conditions, and in peak flexion moment among anterior translation, baseline, and extension conditions). In the coronal plane, similar effects were found in the magnitudes of the moments in the early stance (p < 0.01 at 5 %, 20 %, and 75 % stance). A significant difference in magnitude was observed in the late stance (p < 0.01 between adduction and medial translation conditions).

SIGNIFICANCE

The timing of the socket reaction moment may be different in the sagittal plane, while the magnitudes of the socket reaction moment in the late stance may be different in the coronal plane between the angular and translational alignment changes.

The effect of prosthetic alignment on the stump temperature and ground reaction forces during gait in transfemoral amputees

BACKGROUND

Lower limb prosthetic alignment is a procedure mostly subjective. A prosthetic misaligned induces gait deviations and long-term joint diseases. The alignment effects for each lower limb and the stump stays uncertain.

RESEARCH OBJECTIVE

To identify the effect of the transfemoral alignment prosthesis on ground reaction forces and thermal images of the residual limb.

METHODS

The effect of misalignment and nominal alignment was evaluated in sixteen transfemoral amputees. The nominal alignment was considered as the optimal alignment for each subject. Misalignment included random variations in the anterior-posterior and medial-lateral translation of the prosthetic foot and the angle of flexion-extension, abduction-adduction, and internal-external rotation of the socket and prosthetic foot. The control group consisted of fifteen non-amputee individuals. The ground reaction force parameters and stump temperature were analyzed for each alignment condition. The statistical analysis included the one-way ANOVA, Kruskal-Wallis, and multiple comparison tests.

RESULTS

The prosthesis did not produce statistically significant changes in the average temperature of residual limbs. However, the temperature distribution on the stump skin was different (P < 0.05). The transfemoral prosthesis misalignment produced an irregular heat diffusion on the anterior, posterior, and lateral sides of the stump contour compared to the nominal alignment (P < 0.05). The sound limb did not show differences between nominal alignments and misalignments for most ground reaction force parameters. For almost all GRF parameters, significant differences were observed for the prosthetic limb between misalignment and nominal alignment (P < 0.001). The symmetry indices of ground reaction force parameters of transfemoral amputees did not show any kind of significant improvements after aligning the prosthesis nominally.

SIGNIFICANCE

The stump's temperature distribution and the ground reaction force findings for the prosthetic limb provide a better understanding of the alignment procedure of the transfemoral prosthesis and improve the amputees' compliance to the prosthesis.

Scoping review to evaluate existing measurement parameters and clinical outcomes of transtibial prosthetic alignment and socket fit

INTRODUCTION

Fit and alignment are observable objectives of the prosthesis rendering process for individuals with lower limb amputation. Nevertheless, there is a dearth of validated measures to directly assess the quality of this clinical procedure.

OBJECTIVES

The objectives of this scoping review are to evaluate existing measurement parameters and clinical outcomes used in investigations of transtibial socket fit or prosthetic alignment and to identify gaps in the literature regarding tools for evaluation of prosthetic fitting.

STUDY DESIGN

Scoping literature review.

METHODS

A comprehensive search was conducted in the following databases: MEDLINE (through PubMed), Embase (through Elsevier), Scopus (through Elsevier), and Engineering Village (through Elsevier), resulting in 6107 studies to be screened.

RESULTS

Sixty-three studies were included in the review. When measuring fit, studies most frequently reported on patient-reported comfort (n = 22) and socket size compared with the residual limb volume (n = 9). Alignment was most frequently measured by the prosthetists' judgment and/or use of an alignment jig (n = 34). The measurement parameters used to determine alignment or fit varied greatly among the included studies.

CONCLUSION

This review demonstrated that most measures of socket fit rely on a patient's self-report and may vary with biopsychosocial factors unrelated to the socket fitting process. Meanwhile, alignment is determined mostly by the prosthetist's judgment, paired with objective measurements, such as alignment jigs and gait analysis. Efforts to standardize and validate measures of these parameters of prosthetic fitting are vital to improving clinical practice and reporting outcomes.

Design of lower limb prosthetic sockets: a review

INTRODUCTION

The prosthetic socket is the connecting part between the stump and the prosthesis, which is the important basis for the function of the prosthesis. The current prosthetic socket is difficult in meeting the needs of amputees current, which is the main reason for amputees abandoning their prostheses. This paper reviews the design and use of prosthetic sockets for lower limb.

AREAS COVERED

The contribution of this publication is to review the skin problem, interface stress and volume fluctuations for prosthetic sockets, which are proposed as the key factors affecting the use of prosthetic sockets. Moreover, the lower limb prosthetic sockets are classified into the full-contact and the frame-type sockets according to the different contact type between stump and prosthetic socket, and their advantages and disadvantages are analyzed from different perspectives.

EXPERT OPINION

Aim to design the prosthetic socket with function transfer, suspension stability and comfort of socket, a design concept for prosthetic socket with self-adapt in real-time is proposed. It can be achieved by the smart materials with special mechanical properties.

Influence of coronal and sagittal prosthetic foot alignment on socket reaction moments in transtibial prostheses during walking

BACKGROUND

The socket reaction moment (SRM) has been reported to change because of alignment changes in transtibial prosthetic sockets. However, the influence of prosthetic foot alignment on SRM remains unclear.

RESEARCH QUESTION

Are SRMs predictable from alignment changes of prosthetic feet?

METHODS

Ten users of transtibial prostheses participated in this study. Under five alignment conditions (3 ° plantarflexion and dorsiflexion, 6 ° inversion and eversion, and baseline alignment), temporal-spatial parameters and sagittal and coronal SRMs were measured during walking. Cadence, walking speed, step time, single support time, and step length were compared. The maximum/minimum SRM, % stance (timing) of the maximum/minimum SRM, Zero-cross, and SRMs at 5 %, 20 %, and 75 % stance were extracted and compared. Repeated measures analysis of variance or Friedman tests, and linear regression analyses were conducted for statistical analyses (i.e., alignment conditions as independent variables and SRM parameters as dependent variables).

RESULTS

The SRMs at 5%, 20 %, and 75 % stance showed significant differences under coronal angular changes. The minimum SRM, % stance of the minimum/maximum SRM, and Zero-cross showed significant differences under sagittal alignment changes. In linear regression analysis, the minimum SRM, % stance of the minimum/maximum SRM, SRM at 20 % stance, and Zero-cross were significant dependent variables in the sagittal plane. The maximum/minimum SRM, SRM at 20 % and 75 % stance, and % stance of the minimum SRM were significant dependent variables in the coronal plane.

SIGNIFICANCE

The results indicated that the changes in prosthetic feet angles may predict the magnitude of SRM (maximum/minimum SRM, SRM at 20 % and 75 % stance) in the coronal plane, and the timing of SRM (Zero-cross, % stance of the maximum/minimum SRM) in the sagittal plane. These findings suggest that the SRM may be useful for evaluating foot alignment in transtibial prostheses.

Advanced techniques in amputation surgery and prosthetic technology in the lower extremity

Bone-anchored implants give patients with unmanageable stump problems hope for drastic improvements in function and quality of life and are therefore increasingly considered a viable solution for lower-limb amputees and their orthopaedic surgeons, despite high infection rates.Regarding diversity and increasing numbers of implants worldwide, efforts are to be supported to arrange an international bone-anchored implant register to transparently overview pros and cons.Due to few, but high-quality, articles about the beneficial effects of targeted muscle innervation (TMR) and regenerative peripheral nerve interface (RPNI), these surgical techniques ought to be directly transferred into clinical protocols, observations and routines.Bionics of the lower extremity is an emerging cutting-edge technology. The main goal lies in the reduction of recognition and classification errors in changes of ambulant modes. Agonist-antagonist myoneuronal interfaces may be a most promising start in controlling of actively powered ankle joints.As advanced amputation surgical techniques are becoming part of clinical routine, the development of financing strategies besides medical strategies ought to be boosted, leading to cutting-edge technology at an affordable price.Microprocessor-controlled components are broadly available, and amputees do see benefits. Devices from different manufacturers differ in gait kinematics with huge inter-individual varieties between amputees that cannot be explained by age. Active microprocessor-controlled knees/ankles (A-MPK/As) might succeed in uneven ground-walking. Patients ought to be supported to receive appropriate prosthetic components to reach their everyday goals in a desirable way.Increased funding of research in the field of prosthetic technology could enhance more high-quality research in order to generate a high level of evidence and to identify individuals who can profit most from microprocessor-controlled prosthetic components. Cite this article: EFORT Open Rev 2020;5:724-741. DOI: 10.1302/2058-5241.5.190070.

Using mechanical testing to assess texturing of prosthetic sockets to improve suspension in the transverse plane and reduce rotation

Creating a secure and comfortable linkage between the residual limb and prosthetic socket in persons with lower limb amputation is a critical factor for successful rehabilitation, including ambulation and other activities of daily living. Unwanted rotation within the socket can be a clinical problem for prosthesis users. One way of addressing issues experienced with transverse plane control of the socket may be through increased friction interface forces. It has been proposed that friction at the residual limb/socket interface may be increased by adding texture to interface components. Three-dimensional (3D) printing may be used to fabricate sockets with texture patterns added to the inner socket surface. Hence, the aim of this study was to investigate the effects of socket texturing on transverse plane rotation of the socket on a mock residual limb under two suspension conditions: passive suction and active vacuum. To conduct this study, we developed a mechanical testing protocol as no standardized tests currently exist to assess prosthetic sockets. Sockets with 14 different texture patterns were fabricated using the Squirt-Shape^™ 3D printer. Textured sockets were compared to an Original Squirt-Shape (OSS) socket and a smooth thermoformed socket. Sockets were fitted with a mock residual limb and bi-axially loaded to 350 N compression with simultaneous rotation (2.5°, 5° and 7.5°) using a custom rotation assembly attached to a uniaxial hydraulic material testing system. There was a statistically significant three-way interaction between suspension, angle and texture (p < 0.0005). Torques between textured and reference sockets, for all rotation angles and both suspension conditions, were significantly different (p < 0.0005). Using newly developed testing protocols, it was demonstrated that some texture patterns significantly increased torque (i.e., resistance against unwanted rotation) in the transverse plane compared to both OSS and smooth sockets, especially for passive suction. Rotation testing of sockets may provide insight into socket design to improve suspension in the transverse plane.

A Comparison of the Conventional PiG Marker Method Versus a Cluster-Based Model when recording Gait Kinematics in Trans-Tibial Prosthesis Users and the Implications for Future IMU Gait Analysis

Validation testing is a necessary step for inertial measurement unit (IMU) motion analysis for research and clinical use. Optical tracking systems utilize marker models which must be precise in measurement and mitigate skin artifacts. Prosthesis wearers present challenges to optical tracking marker model choice. Seven participants were recruited and underwent simultaneous motion capture from two marker sets; Plug in Gait (PiG) and the Strathclyde Cluster Model (SCM). Variability of joint kinematics within and between subjects was evaluated. Variability was higher for PiG than SCM for all parameters. The within-subjects variability as reported by the average standard deviation (SD), was below 5.6° for all rotations of the hip on the prosthesis side for all participants for both methods, with an average of 2.1° for PiG and 2.5° for SCM. Statistically significant differences in joint parameters caused by a change in the protocol were evident in the sagittal plane (p < 0.05) on the amputated side. Trans-tibial gait analysis was best achieved by use of the SCM. The SCM protocol appeared to provide kinematic measurements with a smaller variability than that of the PiG. Validation studies for prosthesis wearer populations must reconsider the marker protocol for gold standard comparisons with IMUs.