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The impact of using an upper-limb prosthesis on the perception of real and illusory weight differences

The impact of using an upper-limb prosthesis on the perception of real and illusory weight differences

Most research on prosthetic use examines prosthetic users functional ability to undertake activities of daily living (Haverkate, Smit, & Plettenburg, 2016; Wallace et al., 1999). However, our hands not only are tools to manipulate our environment but they also provide the main method to experience nonvisible properties of objects such as centre of mass, temperature, and weight (Gallace & Spence, 2014). Despite the critical role that our hands play in this regard, almost no work has examined how the use of an upper-limb prosthesis might affect the hedonic perception of manually acquired properties such as object weight. To date, the one study to examine perception in upper-limb prosthetic users has done so in the context of the perceptual sensitivity of weight discrimination. Wallace et al. (2002) compared the difference threshold of a single long-term prosthetic user to that of a group of controls using either their anatomical hand or a prosthesis simulator. The authors found that the long-term prosthetic user was just as proficient as an intact control group at discriminating between objects of different mass. However, when using the prosthetic simulator, controls were significant- ly worse compared with when they used their anatomical * Gavin Buckingham

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Osseointegrated total hip replacement connected to a lower limb prosthesis: a proof-of-concept study with three cases

Osseointegrated total hip replacement connected to a lower limb prosthesis: a proof-of-concept study with three cases

Traditionally, transfemoral amputees have been rehabili- tated using a socket prosthesis. However, over the past two decades, innovative surgical techniques that connect the lower limb prosthesis directly to the bone via osseointegration have emerged. These techniques were developed to overcome reductions in amputee quality of life, which occur secondary to socket-residuum interface problems including significant discomfort, poor fit, lack of rotational control, reduced proprioception, and asso- ciated energy loss due to prosthetic pistoning [1 – 3]. The structural and functional connection between the macroporous surface of metal implants and living bone

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A mechatronic system for achieving optimum alignment of lower limb prosthesis

A mechatronic system for achieving optimum alignment of lower limb prosthesis

Anatomically, human body consists of multiple joints and segments, rotating about their axis. For lower limbs (shown in Figure 2.5), Winter [27] defined the hip angle as the difference between the trunk and the thigh, the knee angle as the difference between the thigh and the shank, the ankle angle as the difference between the foot and the shank. Based on these definitions, the angular displacement can be measured and computed. Angular velocity and angular acceleration are the first and the second derivatives of the angular displacement respectively. Healthy joints consist of more than one degree-of-freedom, considering the type of joints in the leg. The hip joint is a ball and socket joint; the knee joint is not pivoted at a fixed revolute point while the foot comprises of multiple-linked bones and joints. A major concern of prescribing a lower limb prosthesis and the alignment is the capability of motions at the AP plane.

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Comparison of vibrotactile and joint-torque feedback in a myoelectric upper-limb prosthesis

Comparison of vibrotactile and joint-torque feedback in a myoelectric upper-limb prosthesis

Fourth, the haptic feedback was held constant after reaching the target aperture threshold (E t ), which is not representative of true force perception when squeezing objects. We avoided the natural increase in force that occurs when squeezing an object because the load cell, in addition to measuring the object force, also measured the spring force of the terminal device and the friction in the Bowden cable, which could mask the force of the block and cause difficulty in perceiving the difference between two blocks. By holding the feedback constant after passing E t , we intended to ensure distinct feedback for each test object despite the hardware limitations. This limitation, in addition to the ones mentioned above, would not come into play in a traditional myoelectric prosthesis or a body- powered device as there would be no linear actuator or load cell. Here, we attempted to control for these factors. While cable friction is present in standard body-powered devices, amputees learn to account for this friction with long-term repeated use. We were unable to provide the amount of training for our able-bodied participants to reach this level of proficiency. Additionally, even though the zero-order hold on feedback reduces to force discrim- ination, the inclusion of visual information encourages the integration of both force and aperture. Consequently, it is feasible for participants to discriminate the various objects based on more than just the haptic feedback of force. Finally, it is worth mentioning that a commercial myoelectric prosthesis outfitted with force sensors on the end effector could be used in future experiments.

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Kinetics of lower limb prosthesis: automated detection of vertical loading rate

Kinetics of lower limb prosthesis: automated detection of vertical loading rate

The loading profile can be calculated using inverse dynamics equations, providing the comprehensive dynamics and kinematics information responsible for the prosthetic and sound ankle, knee and hip joint kinetics [18–25]. However, this method relies on fixed equipment placed in delimited space. Ground reaction forces are collected using floor-mounted force-plates in walkways, stairs or ramps. Positions of lower limb segments within a calibrated volume are captured using 3D motion analysis systems [18,19,26,27]. Valid dynamic measurements require sole contact of each foot on a force-plate that could be achieved through individualized arrangements of the starting point and/or force-plate positioning to avoid targeting and/or repetitive recording of invalid trials [18–20]. The sum of steps to be collected in a session is conditioned by the number and arrangement of force-plates and cameras [18–20]. Otherwise, shortcomings with foot placement and the number of steps could be alleviated by using an instrumented treadmill, provided that 3D motion capture has the capacity to record for an extended period of time. Finally, inverse dynamics calculations are potentially sensitive to accurate extraction of inertial characteristics of prosthetic components [28,29].

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An Investigation into a Gear Based Knee Joint Designed for Lower Limb Prosthesis

An Investigation into a Gear Based Knee Joint Designed for Lower Limb Prosthesis

mechanisms adopted by the amputee walking with an above- knee (AK) prosthesis are determined by the joint kinetics [4]. The finite-element analysis of knee joint components would provide an idea on knee joint kinematics and thus enable the designers to predict the component failure by analyzing the simulation results. Using FEA, Zach et al. [5] have ana- lyzed the plastic stability and von Mises stress of the material and the contact pressure distribution on the components ’ surfaces during knee-bending in 28.41 ° . The variations of the von Mises stress distributions in bipolar hemi-knee pros- thesis and unipolar prosthesis were observed by Lian et al. [6] when the prosthesis was moved at a different gait cycle under static upright posture. Maximum stress values were also determined based on the dynamic analysis of the unipolar and bipolar joint prostheses.

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Retrospective Study on External Canine Limb Prosthesis used in 24 patients

Retrospective Study on External Canine Limb Prosthesis used in 24 patients

Prior to surgery, the level of the amputation for the soft tissues is marked distally, while the boney anatomy is marked proximally on the skin. The initial incision should be planned so that the closed incision does not lie over the distal or palmar/plantar surface of the residuum to ensure that the incisional scar does not adhere to the underlying bone (Canapp et al., 2012; Canapp et al., 2014; Bowker et al., 1992). It is vital that the soft tissues are handled carefully to prevent unnecessary trauma; good soft tissue coverage of the residuum will resist the shear forces involved in prosthetic ambulation and help maintain residual limb integrity (Canapp et al., 2012; Canapp et al., 2014; Bowker et al., 1992). A transverse osteotomy, at the most distal level possible, is made across the bone(s), proximal to the initial skin incision and soft tissue transection, and the distal limb is removed. The cortical bone edges should be smoothed to prevent sharp edges causing soft tissue trauma (Canapp et al., 2014; Bowker et al., 1992; Ert Reconstruction Technique, 2015; Decoster et al., 2006). The medullary cavity should be packed with bone wax to help provide hemostasis from the medullary canal. Hemostasis is especially important to obtain in amputations as hemorrhage will predispose the residuum to post-operative seromas (Canapp et al., 2012; Canapp et al., 2014; Bowker et al., 1992). To begin closure, muscles, tendons and fascia from the caudal limb are wrapped around the end of the bone and apposed to the muscles, tendons and fascia on the opposite side of the bone in a mattress pattern using a long-lasting monofilament suture (Canapp et al., 2012; Canapp et al., 2014). While it is not well defined for small animals, it is recognised that weight bearing occurs at the caudodistal aspect of the residuum. Thus, the surgeon should avoid creating possible weak points over the caudodistal surface as it could predispose the residuum to future soft tissue break down (Canapp et al., 2012; Canapp et al., 2014). Once all muscles, tendons and fascia are apposed, the skin incision should be closed over the cranial surface of the residuum with minimal to no tension to reduce the chances of ulcerations and to promote healing post-operatively (Canapp et al., 2012; Canapp et al., 2014). Skin sutures may be preferred to skin staples as they are considered more comfortable and are associated with a lessened risk for post-operative incisional infection (Smith et al., 2010).

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Evaluation of EMG pattern recognition for upper limb prosthesis control: a case study in comparison with direct myoelectric control

Evaluation of EMG pattern recognition for upper limb prosthesis control: a case study in comparison with direct myoelectric control

USA). These 2 DOFs (wrist pronate/supinate and ter- minal device open/close) were selected because most transradial amputees who use myoelectric devices only use one or two active joints, and these are the ones most commonly used. The prosthesis was mounted on the ex- perimental socket, which was customized for each sub- ject. Six active EMG electrodes (TRIAD Preamp, Motion Control, Inc., USA) were embedded within the experi- ment socket for surface EMG signal measurement. Two electrodes were used for DC and all six electrodes were used for PR control. The gain for each electrode was set by inspecting the display of EMG signals in real time on a computer screen. Both DC and EMG PR were imple- mented on our own computing processor (Texas Instru- ments OMAP3503 600 MHz processor based on the ARM Cortex-A8 architecture) [25]. EMG signals were sampled at 1000 Hz and digitally filtered between 20 and 450 Hz. Two of six electrodes were placed on the DC sites identified by a certified prosthetist. These two EMG electrodes were placed over the residual limb, where independent EMG activations were recorded while amputees attempted wrist/finger flexion and ex- tension. The gain for each channel was then manually set by the prosthetist in order to use the entire dynamic range of the recorded EMG signal. Four additional EMG electrode locations were selected by palpating residual limb muscles and checking EMG recordings when the subjects were instructed to perform hand open/close and wrist pronation/supination. Note that since EMG crosstalk has little influence on the performance of EMG PR [31], targeting specific muscles for EMG elec- trode placement was not necessary.

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Flexible and static wrist units in upper limb prosthesis users: functionality scores, user satisfaction and compensatory movements

Flexible and static wrist units in upper limb prosthesis users: functionality scores, user satisfaction and compensatory movements

By multiplying the inverse rotation matrices of the MTw™ sensors of the trunk by the rotation matrices of the upper arm sensors, the rotation matrices of the shoulder angles were computed at each timeframe. Be- cause we often found gimbal lock when computing Euler angles following [23], we computed attitude vectors [24]. Euler angles, which are conventionally reported in re- habilitation and movement science, decompose a rota- tion from one pose to another into three rotations, each around an axis of an orthogonal local reference frame. Although usually represented in the literature with three angles, a rotation in a joint of the arm such as the shoulder joint is actually a rotation around one axis through that joint. The attitude vec- tor represents the orientation of that axis and the length of the attitude vector reflects the amount of rotation with respect to the axis. We computed the length of the attitude vector at each timeframe, over the course of the movement. The maximum values of the attitude vectors within each trial were averaged over the repetitions in each task for each participant, reflecting the maximum angles of rotation in the shoulder (i.e., the rotation angle). If this angle of rota- tion was larger, the degree of movement in the shoul- der was larger. We compared these angles of rotation for the different conditions to assess whether more compensatory movements were performed. Descrip- tive statistics were presented for these maximum an- gles of rotation in the shoulder for all tasks in all conditions of the prosthesis users and for the control subjects.

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The effect of surface inclination and limb on knee loading measures in transtibial prosthesis users

The effect of surface inclination and limb on knee loading measures in transtibial prosthesis users

Past literature outlined the importance of KAM-F due to its larger magnitude [17, 20, 21] and steeper rise rate [12]. KAM-S could help identify disease severity since individuals with more severe OA have shown differences when compared to AB individuals [17]. However, since KAM-S showed no significant differences across all tested variables, further research is needed to verify KAM-S as a predictive factor for OA onset in lower limb prosthesis users. The KAM-S variables extracted from this study were lower than previously established values in the literature with similar non-significant findings when comparing different prosthetic foot types [48]. Table 5 First peak knee moment impulse (Nm/kg * s) across 4 limbs and 5 surfaces. Standard deviation is in brackets

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Upper- and lower-limb amputees show reduced levels of eeriness for images of prosthetic hands

Upper- and lower-limb amputees show reduced levels of eeriness for images of prosthetic hands

We found clear evidence that the type of experience with a prosthesis affects the uncanny phenomenon with this type of stimulus. This study is the first to show that both upper- and lower-limb prosthetic limb users found the realistic and unre- alistic cosmetic prostheses to be significantly less eerie than the other groups, despite no difference in the ratings of human-likeness for these stimuli. With regards to the people with upper-limb absence, it may be that this effect is simply related to visual familiarity – it is one of the most reliable findings in psychology that exposure to a stimulus increases one ’ s liking toward it (Bornstein, 1989). Given that all of the individuals in the upper-limb absence group were long-term users of an upper-limb prosthesis, who would have had con- siderably more experience with these types of limbs than any of the other groups, any inherent feeling of eeriness or disgust may have been mitigated by this visual familiarity. This sug- gestion is consistent with recent work in the context of human- robot interaction, which has suggested that prolonged expo- sure appears to reduce the sensation of unease induced by a lifelike robot designed to induce the uncanny phenomenon (Złotowski et al., 2015). It is less easy, however, to explain this effect in the lower-limb prosthesis users, who seem un- likely to have had more visual exposure to an upper-limb prosthetic device than members of the prosthetist group. It could be speculated that the general use of a prosthesis, or indeed the absence of a limb, renders an individual less sus- ceptible to the uncanny phenomenon by virtue of having weaker prior expectations of the associations between biolog- ical images and non-biological features, and thus less of a response to violations of this relationship (Saygin et al., 2012). This is clearly is a topic that warrants further study, given prosthesis users’ diverse range of preferences for anatomically-realistic prosthetic hands versus the B high-tech ^

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Estimation of Actuation System Parameters for Lower Limb Prostheses

Estimation of Actuation System Parameters for Lower Limb Prostheses

torque ( ), maximum speed required from the actuator ( ), maximum position ( ) allowed by the mechanism, and the inertia of the mechanical components of the system [9-11]. The required actuators for the lower limb prosthesis’ joints are a significant issue because if the actuator power is underestimated, the adequate power is not delivered across the prosthetic joint to accomplish the intended function. On the other hand, if the selected actuator is overestimated/oversized, it could cost more and the system will end up with large and heavy actuation joint. The actuation transmission mechanism that is used to convert the motion type and amplify the torque delivered to the joint plays an important role in fulfilling the system requirements. The challenge in the actuation system design is to find the optimum combination of actuator, transmission mechanism and power source with minimum weight to produce the required torque and kinematics requirements.

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Implantation of customized 3 D printed titanium prosthesis in limb salvage surgery: a case series and review of the literature

Implantation of customized 3 D printed titanium prosthesis in limb salvage surgery: a case series and review of the literature

The rapid prototyping (RP) is a process which directly generates physical objects with defined structure and shape on the basis of virtual mode data. The commonly used RP techniques include stereolithography (SLA), se- lective laser sintering (SLS), fused deposition modeling (FDM), laminated object manufacturing (LOM), inkjet printing, and electron beam melting (EBM). EBM is a kind of 3-D printing technique. It can be used to fabricate me- tallic components with complex shapes and porous struc- tures [15]. The irregular bones (clavicle, scapula, and ilium) have unique dimensions. Therefore, it may be a feasible solution to design customized prosthesis and manufacture it rapidly. Ti-6Al-4V (TAV) alloy scaffolds manufactured by EBM have shown complete osteointegra- tion within 60 days in animal study [16]. In patients with maxillofacial reconstruction, TAV implants manufactured by EBM were used to repair the zygomatico-orbital de- fects. The individual digital planning procedures, rapid prototyping, and titanium implants were proved to be ef- fective [17]. However, few studies focus specifically on the application of customized 3-D-printed TAV prosthesis in limb salvage surgeries until now. There is also a lack of in- formation on the prosthesis survival, functional outcomes, and complications.

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Prosthetic energy return during walking increases after 3 weeks of adaptation to a new device

Prosthetic energy return during walking increases after 3 weeks of adaptation to a new device

After 3 weeks of adaptation to a new prosthetic device, users exhibited an increase in positive prosthesis and sound ankle-foot work, as well as an increase in self- selected speed. Increased prosthesis work could reflect a greater step-by-step utilization of a prosthesis’ spring-like property, suggesting that prosthesis users can change their gait mechanics to better interact with their prosthesis. Analyzing mechanical work profiles may be desirable for tracking gait rehabilitation or response to a prosthesis over time. Future directions for this work could entail analyzing new prosthesis users to fully understand the process of prosthesis adaptation, correlating mechanics-based mea- sures to patient-reported outcomes (such as comfort, ease of use, appearance, and sound), and determining whether targeted interventions could further increase prosthetic energy utilization.

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A comprehensive musculoskeletal and peripheral nervous system assessment of war-related bilateral upper extremity amputees

A comprehensive musculoskeletal and peripheral nervous system assessment of war-related bilateral upper extremity amputees

There is also limited information about routine clinical examination of upper limb amputations. Successful pros- thetic rehabilitation requires adequate muscle strength and normal joint motion [12, 13]. Amputees with bilateral upper extremity amputation may need to accommodate for lost wrist, forearm and/or elbow motion by extreme motion at other articulations such as teeth, chin, and lower limbs to compensate for the loss of their hand/wrist func- tion. The risk of musculoskeletal pain may increase be- cause of these dysfunctional movements. Musculoskeletal pain and disorders often occur in upper limb amputations [14]. Pain and other grievances may affect physical func- tion as well [15].

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<p>Interprosthetic femoral fractures: management challenges</p>

<p>Interprosthetic femoral fractures: management challenges</p>

screws due to the presence of prior arthroplasty implants, the use of cerclage cables or unicortical locking screws may supplement fi xation (Figure 4). Additionally, in the presence of a cruciate retaining TKA or one with an open box con fi guration, a retrograde nail may be used. This is typically used in the setting of a revision or interprosthetic nonunion where a supplemental plate is also used, as the nail is unable to overlap the hip stem and causes an area of stress concentration just distal to the hip prosthesis (Figure 5). A recent case series performed by Hussain et al review 9 IFFs treated with a combination of a retrograde nail and laterally locked plate. Fixation proximal to the fracture included an average of 3 bicortical screws and one uni- cortical screw, and a minimum of four cortices of fi xation. They observed a 100% union rate with immediate weight- bearing. 30 Utilization of the intramedullary nail functions biologically and biomechanically. Reaming the canal for the nail allows for cancellous bone to be impacted into the fracture site after preliminary reduction with the plate. Biomechanically, an intramedullary nail imparts longitudi- nal and rotational stability and enhances fi xation stability. Due to the relatively low incidence of IFFs, the clinical literature is primarily in the form of case reports and case series. Recently, however, Bonnevialle et al conducted a retrospective, multicenter study of 51 patients with a mean age of 82.5 years who suffered an IFF between 2009 and 2015. At a mean follow-up of 27 months, there were 6 mechanical complications, 2 surgical site infections, and 2 cases of loosening, illustrating the morbid nature of this injury. The overall mortality at fi nal review was 31% (9 deaths in the fi rst 6 months) with a median survival of 3.45 years. 13

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Study of modelling approach on nose prosthesis
compared to human smell sensing activity with
advanced design technique

Study of modelling approach on nose prosthesis compared to human smell sensing activity with advanced design technique

Prosthesis is an artificialize device that designed to substitute for missing or diseased body parts like ears, eyes, noses, limbs, arms, legs and so on and interfaced them with human brain. The detection process of prosthetic nose is done in two ways, (1) an array of chemical (gas) sensors and (2) signal processing system. Odor recognition is the main mechanism for each sensor lying on the array that has different sensitivity of the measured gas and the pattern recognizer compares the pattern accordance with the measurements to store patterns for the recognized ones in signal processing system.

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Study of Transtibial Prosthesis at ALC, Chennai, with Special Reference to Modular Prosthesis

Study of Transtibial Prosthesis at ALC, Chennai, with Special Reference to Modular Prosthesis

WHO estimates that there are 800 million persons with disability in the world and 100 million of them are in India alone. National sample survey organization (The Survey in the 58 th Round) in 2002 has shown that 1.85 crore disabled person i.e. 1.8% of the total estimated population present in our country. Of them, 10.66 million (58% of all the disabled) are having Locomotor Disability. There are 8.3 lakh (78/1000 disabled) are with limb loss (NSSO, 2002). Amongst them, most are Transtibial amputee and they need a prosthetic device of appropriate design and at a reasonable cost to perform as effective as the lost limb.

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3D Printed Prosthesis Replacement for Limb Salvage after Radical Resection of an Ameloblastoma in the Tibia with 1 Year of Follow Up: A Case Report

3D Printed Prosthesis Replacement for Limb Salvage after Radical Resection of an Ameloblastoma in the Tibia with 1 Year of Follow Up: A Case Report

In this case, ameloblastoma has a wide range of lesions, ac- counting for more than 75% of the total length of the tibia. If the bone of the diseased limb is reconstructed with a large seg- ment of allograft, the bone regeneration will be slow, and the possibility of complications, such as allograft rejection, frac- ture, and nonunion, will increase. As mentioned above, local stress to a hinged prosthesis will be more intense and compli- cations, such as loosening and talus collapse, will occur more readily. 11,16 There are still complications, such as talus prosthe-

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SoftHand at the CYBATHLON: a user’s experience

SoftHand at the CYBATHLON: a user’s experience

The CYBATHLON provided a unique experience to test the novel SHP and SHPH prostheses in a rigorous and competitive environment alongside both research and commercial prosthetic systems. The Pilot performed well with both devices, and the experience helped illustrate the advantages and disadvantages of the terminal device and different control modes used. In the CYBATHLON rehearsal, the Pilot placed third out of four competing teams; the three other teams all competed using com- mercial prosthetic hands, although two of these used a research control method. During the training session, the Pilot became proficient in myoelectric control. How- ever, fatigue was a real challenge that over time lead to increased co-contraction of the muscles controlling the prosthesis and thus reduced performance. This was likely due to a combination of factors: First, the Pilot had rel- atively little overall exposure to myoelectric control, and muscle fatigue is to be expected in new users of myoelec- tric devices; it is conceivable that with daily use, the Pilot would have been able to use the device longer without suffering fatigue. Second, the myoelectric socket and SHP are heavier than the Pilot’s typical prosthesis and do not have the potential off-loading provided by the shoulder harness. Further, the myoelectric socket requires a more snug fit and, in order to ensure good contact with the electrodes, does not allow the possibility of using a pros- thetic sock. The myoelectric socket for the Pilot, who has a relatively short residual limb, also limited elbow range of motion and created some discomfort over time due to the increased pressure.

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