Cutaneous sensitivity in unilateral trans-tibial amputees

PubMed Central

Templeton, Cale A.; Strzalkowski, Nicholas D. J.; Galvin, Patti

2018-01-01

Aim To examine tactile sensitivity in the leg and foot sole of below-knee amputees (diabetic n = 3, traumatic n = 1), and healthy control subjects (n = 4), and examine the association between sensation and balance. Method Vibration perception threshold (VPT; 3, 40, 250Hz) and monofilaments (MF) were used to examine vibration and light touch sensitivity on the intact limb, residual limb, and homologous locations on controls. A functional reach test was performed to assess functional balance. Results Tactile sensitivity was lower for diabetic amputee subjects compared to age matched controls for both VPT and MF; which was expected due to presence of diabetic peripheral neuropathy. In contrast, the traumatic amputee participant showed increased sensitivity for VPT at 40Hz and 250Hz vibration in both the intact and residual limbs compared to controls. Amputees with lower tactile sensitivity had shorter reach distances compared to those with higher sensitivity. Conclusion Changes in tactile sensitivity in the residual limb of trans-tibial amputees may have implications for the interaction between the amputee and the prosthetic device. The decreased skin sensitivity observed in the residual limb of subjects with diabetes is of concern as changes in skin sensitivity may be important in 1) identification/prevention of excessive pressure and 2) for functional stability. Interestingly, we saw increased residual limb skin sensitivity in the individual with the traumatic amputation. Although not measured directly in the present study, this increase in tactile sensitivity may be related to cortical reorganisation, which is known to occur following amputation, and would support similar findings observed in upper limb amputees. PMID:29856766

The effects of laterality on obstacle crossing performance in unilateral trans-tibial amputees.

PubMed

De Asha, Alan R; Buckley, John G

2015-05-01

Unilateral trans-tibial amputees have bilaterally reduced toe clearance, and an increased risk of foot contact, while crossing obstacles compared to the able-bodied. While the able-bodied tend to lead with a 'preferred' limb it is equivocal whether amputees prefer to lead with the intact or prosthetic limb. This study determined the effects of laterality, compared to side of amputation, on amputees' obstacle crossing performance. To help understand why laterality could affect performance we also assessed knee proprioception for both limbs. Foot placement and toe clearance parameters were recorded while nine amputees crossed obstacles of varying heights leading with both their intact and prosthetic limbs. Joint-position sense was also assessed. Participants self-reported which limb was their preferred (dominant) limb. There were no significant differences in foot placements or toe clearance variability across lead-limb conditions. There were no significant differences in toe clearance between intact and prosthetic lead-limbs (p=0.28) but toe clearance was significantly higher when amputees led with their preferred compared to non-preferred limb (p=0.025). There was no difference in joint-position sense between the intact and residual knees (p=0.34) but joint-position sense tended to be more accurate for the preferred, compared to non-preferred limb (p=0.08). Findings suggest that, despite the mechanical constraints imposed by use of a prosthesis, laterality may be as important in lower-limb amputees as it is in the able bodied. This suggests that amputees should be encouraged to cross obstacles leading with their preferred limb. Copyright © 2015. Published by Elsevier Ltd.

Effects of diabetic peripheral neuropathy on gait in vascular trans-tibial amputees.

PubMed

Nakajima, Hiroshi; Yamamoto, Sumiko; Katsuhira, Junji

2018-07-01

Patients with diabetes often develop diabetic peripheral neuropathy, which is a distal symmetric polyneuropathy, so foot function on the non-amputated side is expected to affect gait in vascular trans-tibial amputees. However, there is little information on the kinematics and kinetics of gait or the effects of diabetic peripheral neuropathy in vascular trans-tibial amputees. This study aimed to clarify these effects, including the biomechanics of the ankle on the non-amputated side. Participants were 10 vascular trans-tibial amputees with diabetic peripheral neuropathy (group V) and 8 traumatic trans-tibial amputees (group T). Each subject's gait was analyzed at a self-selected speed using a three-dimensional motion analyzer and force plates. Ankle plantarflexion angle, heel elevation angle, and peak and impulse of anterior ground reaction force were smaller on the non-amputated side during pre-swing in group V than in group T. Center of gravity during pre-swing on the non-amputated side was lower in group V than in group T. Hip extension torque during loading response on the prosthetic side was greater in group V than in group T. These findings suggest that the biomechanical function of the ankle on the non-amputated side during pre-swing is poorer in vascular trans-tibial amputees with DPN than in traumatic trans-tibial amputees; the height of the center of gravity could not be maintained during this phase in vascular trans-tibial amputees with diabetic peripheral neuropathy. The hip joint on the prosthetic side compensated for this diminished function at the ankle during loading response. Copyright © 2018 Elsevier Ltd. All rights reserved.

Robotic lower limb prosthesis design through simultaneous computer optimizations of human and prosthesis costs

NASA Astrophysics Data System (ADS)

Handford, Matthew L.; Srinivasan, Manoj

2016-02-01

Robotic lower limb prostheses can improve the quality of life for amputees. Development of such devices, currently dominated by long prototyping periods, could be sped up by predictive simulations. In contrast to some amputee simulations which track experimentally determined non-amputee walking kinematics, here, we explicitly model the human-prosthesis interaction to produce a prediction of the user’s walking kinematics. We obtain simulations of an amputee using an ankle-foot prosthesis by simultaneously optimizing human movements and prosthesis actuation, minimizing a weighted sum of human metabolic and prosthesis costs. The resulting Pareto optimal solutions predict that increasing prosthesis energy cost, decreasing prosthesis mass, and allowing asymmetric gaits all decrease human metabolic rate for a given speed and alter human kinematics. The metabolic rates increase monotonically with speed. Remarkably, by performing an analogous optimization for a non-amputee human, we predict that an amputee walking with an appropriately optimized robotic prosthesis can have a lower metabolic cost - even lower than assuming that the non-amputee’s ankle torques are cost-free.

BODY IMAGE, HOPELESSNESS AND PERSONALITY DIMENSIONS IN LOWER LIMB AMPUTEES

PubMed Central

Bhojak, M.M.; Nathawat, S.S.

1988-01-01

SUMMARY A sample of lower limb amputees and equal number of matched surgical controls was studied on body image, hopelessness and personality dimensions using Fisher's Body Distortion Questionnaire (BDQ). Beck's Hopelessness Scale and Hindi PEN Inventory. Amputees had significantly higher mean scores on body distortion (x 27.86), hopelessness (x 14.08) and neuroticism (x 9.30) as compared to surgical controls. Furthermore they had significantly lesser scores on extraversion (x 11.26) in comparison to their surgical counterparts. No significant differences were found on psychoticism in the two groups. Psychological aspects of amputation have not received much attention. By and large, amputees are believed to have more difficulty in dealing with people than things. It is the loss of ability to relate psychologically, socially, sexually and vocationally that inhibits the amputees most. PMID:21927302

Characterization of evoked tactile sensation in forearm amputees with transcutaneous electrical nerve stimulation

NASA Astrophysics Data System (ADS)

Chai, Guohong; Sui, Xiaohong; Li, Si; He, Longwen; Lan, Ning

2015-12-01

Objective. The goal of this study is to characterize the phenomenon of evoked tactile sensation (ETS) on the stump skin of forearm amputees using transcutaneous electrical nerve stimulation (TENS). Approach. We identified the projected finger map (PFM) of ETS on the stump skin in 11 forearm amputees, and compared perceptual attributes of the ETS in nine forearm amputees and eight able-bodied subjects using TENS. The profile of perceptual thresholds at the most sensitive points (MSPs) in each finger-projected area was obtained by modulating current amplitude, pulse width, and frequency of the biphasic, rectangular current stimulus. The long-term stability of the PFM and the perceptual threshold of the ETS were monitored in five forearm amputees for a period of 11 months. Main results. Five finger-specific projection areas can be independently identified on the stump skin of forearm amputees with a relatively long residual stump length. The shape of the PFM was progressively similar to that of the hand with more distal amputation. Similar sensory modalities of touch, pressure, buzz, vibration, and numb below pain sensation could be evoked both in the PFM of the stump skin of amputees and in the normal skin of able-bodied subjects. Sensory thresholds in the normal skin of able-bodied subjects were generally lower than those in the stump skin of forearm amputees, however, both were linearly modulated by current amplitude and pulse width. The variation of the MSPs in the PFM was confined to a small elliptical area with 95% confidence. The perceptual thresholds of thumb-projected areas were found to vary less than 0.99 × 10-2 mA cm-2. Significance. The stable PFM and sensory thresholds of ETS are desirable for a non-invasive neural interface that can feed back finger-specific tactile information from the prosthetic hand to forearm amputees.

Evaluation of disabilities and activities of daily living of war-related bilateral lower extremity amputees.

PubMed

Ebrahimzadeh, Mohammad H; Moradi, Ali; Bozorgnia, Shahram; Hallaj-Moghaddam, Mohammad

2016-02-01

Long-term consequences and the activities of daily living of bilateral lower limb amputation are not well documented. The aims of our study were to identify the long-term effects of bilateral lower extremity amputations on daily activities and understand how these amputees cope with their mobility assistive devices. Cross-sectional study. A total of 291 veterans with war bilateral lower limb amputations accepted to participate in a cross-sectional study. The average of follow-up was 25.4 years. A total of 152 amputees (54%) were involved in sports averagely 6.7 h per week. Bilateral amputees walk 10 m by the average of 15 ± 33 s, and they could walk continuously with their prosthesis 315 ± 295 m. They wore their prosthesis 6.8 ± 1.7 days per week and 7.9 ± 8.1 h per day. Of these, 6.7% of bilateral lower limb amputees needed help to wear their prosthesis; 88.3% of amputees used assistant device for walking. According to this survey, 73 (42%) prostheses in right limb were appropriate, 95 (54.6%) needed to be replaced, and 6 (3.4) needed to be fixed. On the left side, it was 76 (42%), 92 (52.0%), and 9 (5.1%), respectively. A total of 203 (74.9%) amputees reported limitations in at least one domain of the activities of daily living. The most common single item that affected the patients was ascending and descending stairs by the score of 66% of normal population. Veterans with bilateral lower limb amputations suffering from vast categories of daily problems. This study and its results confirm that bilateral lower limb amputees have major progressive disabilities in daily activities and their social performance. This should attract the attention of amputees' administrative organizations, social workers, health-care providers and caregiver providers. © The International Society for Prosthetics and Orthotics 2014.

Long-term outcomes of unilateral transtibial amputations.

PubMed

Ebrahimzadeh, Mohamad H; Hariri, Sanaz

2009-06-01

the long-term outcomes of wartime transtibial amputations have not been well documented. The purpose of this case series is to present the long-term functional, social, and psychological outcomes of modern-day military unilateral transtibial amputees. the Iranian Veterans Administration of the Khorasan province invited their Iranian military amputees from the Iran-Iraq War (1980-1988) to its medical center for evaluation. The patients filled out a detailed questionnaire and were interviewed and examined by each team member. two hundred (77%) of the 260 invited amputees were willing and able to come back for follow-up. Ninety-six of these patients (48%) were unilateral transtibial amputation. The average follow-up was 17.4 years (range 15-22 years). Land mines were the leading cause of war injury necessitating a transtibial amputation (68%). The most common symptoms about their amputated limbs were phantom sensations (54%), phantom pain (17%), and stump pain (42%). Lower back pain, contralateral (nonamputated limb) knee pain, and ipsilateral (amputated limb) knee pain were reported by 44%, 38%, and 13% of subjects, respectively. Sixty-five percent of patients were employed or had been employed for multiple years after their war injury. All patients were married, and 97% had children. Fifty-four percent of amputees reported psychological problems; 26% were currently utilizing psychological support services. at long-term follow-up, most military transtibial amputees experienced phantom sensation or some type of stump pain. More than half had persistent psychiatric problems, but only about half of these patients were receiving psychological treatment. Although this case series reports the status of these amputees, the next step would be to prospectively follow modern wartime amputees using standardized, validated outcome measures. With the goal of optimizing long-term amputee outcomes, researchers should correlate outcomes with demographics, injury characteristics, and treatments to identify and modify factors affecting the amputees' prognosis.

Skin problems in amputees: a descriptive study.

PubMed

Koc, Erol; Tunca, Mustafa; Akar, Ahmet; Erbil, A Hakan; Demiralp, Bahtiyar; Arca, Ercan

2008-05-01

Skin problems are common in amputee patients. These problems may restrict the normal use of a prosthetic limb. We aimed to determine the range, incidence, causes and patterns of dermatological problems seen in a population of amputees. One hundred and forty two amputees, were enrolled to the study. Age, sex, age at the time of amputation, level of amputation, reason for amputation, and types of prosthesis were noted. Dermatological problems were recorded. Stumps were swabbed for bacteriological and mycological examination, and patch tests were performed in suspected patients. Of these 142 patients, 139 (97.9%) were males and 3 (2.1%) were females. The reasons for amputation in the majority of the cases were wounds due to mine explosion (n = 114, 80.3%) and gunshot wounds (n = 19, 13.4%). The other reasons were arterial diseases, traffic accidents, congenital absence of the tibia, and vascular complication of diabetes. At least one skin problem was detected in 105 (73.9%) of 142 cases. Positive reactions to allergens have been detected in 28 (43%) of 65 cases with dermatitis. Bacterial infection was detected in 12 patients and fungal infection was detected in 4 patients. Our descriptive study shows that skin problems have a high prevalence, up to 73.9% in amputee patients. This high percentage indicates that dermatological problems are important in amputees. Early recognition and treatment of these problems can prevent the amputee's mental, social, and economic losses.

Energy flow analysis of amputee walking shows a proximally-directed transfer of energy in intact limbs, compared to a distally-directed transfer in prosthetic limbs at push-off.

PubMed

Weinert-Aplin, R A; Howard, D; Twiste, M; Jarvis, H L; Bennett, A N; Baker, R J

2017-01-01

Reduced capacity and increased metabolic cost of walking occurs in amputees, despite advances in prosthetic componentry. Joint powers can quantify deficiencies in prosthetic gait, but do not reveal how energy is exchanged between limb segments. This study aimed to quantify these energy exchanges during amputee walking. Optical motion and forceplate data collected during walking at a self-selected speed for cohorts of 10 controls, 10 unilateral trans-tibial, 10 unilateral trans-femoral and 10 bilateral trans-femoral amputees were used to determine the energy exchanges between lower limb segments. At push-off, consistent thigh and shank segment powers were observed between amputee groups (1.12W/kg vs. 1.05W/kg for intact limbs and 0.97W/kg vs. 0.99W/kg for prosthetic limbs), and reduced prosthetic ankle power, particularly in trans-femoral amputees (3.12W/kg vs. 0.87W/kg). Proximally-directed energy exchange was observed in the intact limbs of amputees and controls, while prosthetic limbs displayed distally-directed energy exchanges at the knee and hip. This study used energy flow analysis to show a reversal in the direction in which energy is exchanged between prosthetic limb segments at push-off. This reversal was required to provide sufficient energy to propel the limb segments and is likely a direct result of the lack of push-off power at the prosthetic ankle, particularly in trans-femoral amputees, and leads to their increased metabolic cost of walking. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Evaluation of extreme learning machine for classification of individual and combined finger movements using electromyography on amputees and non-amputees.

PubMed

Anam, Khairul; Al-Jumaily, Adel

2017-01-01

The success of myoelectric pattern recognition (M-PR) mostly relies on the features extracted and classifier employed. This paper proposes and evaluates a fast classifier, extreme learning machine (ELM), to classify individual and combined finger movements on amputees and non-amputees. ELM is a single hidden layer feed-forward network (SLFN) that avoids iterative learning by determining input weights randomly and output weights analytically. Therefore, it can accelerate the training time of SLFNs. In addition to the classifier evaluation, this paper evaluates various feature combinations to improve the performance of M-PR and investigate some feature projections to improve the class separability of the features. Different from other studies on the implementation of ELM in the myoelectric controller, this paper presents a complete and thorough investigation of various types of ELMs including the node-based and kernel-based ELM. Furthermore, this paper provides comparisons of ELMs and other well-known classifiers such as linear discriminant analysis (LDA), k-nearest neighbour (kNN), support vector machine (SVM) and least-square SVM (LS-SVM). The experimental results show the most accurate ELM classifier is radial basis function ELM (RBF-ELM). The comparison of RBF-ELM and other well-known classifiers shows that RBF-ELM is as accurate as SVM and LS-SVM but faster than the SVM family; it is superior to LDA and kNN. The experimental results also indicate that the accuracy gap of the M-PR on the amputees and non-amputees is not too much with the accuracy of 98.55% on amputees and 99.5% on the non-amputees using six electromyography (EMG) channels. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Capability of Fiber Bragg Grating Sensors to Measure Amputees' Trans-Tibial Stump/Socket Interface Pressures

PubMed Central

Al-Fakih, Ebrahim A.; Abu Osman, Noor Azuan; Eshraghi, Arezoo; Adikan, Faisal Rafiq Mahamd

2013-01-01

This study presents the first investigation into the capability of fiber Bragg grating (FBG) sensors to measure interface pressure between the stump and the prosthetic sockets of a trans-tibial amputee. FBG element(s) were recoated with and embedded in a thin layer of epoxy material to form a sensing pad, which was in turn embedded in a silicone polymer material to form a pressure sensor. The sensor was tested in real time by inserting a heavy-duty balloon into the socket and inflating it by using an air compressor. This test was conducted to examine the sensitivity and repeatability of the sensor when subjected to pressure from the stump of the trans-tibial amputee and to mimic the actual environment of the amputee's Patellar Tendon (PT) bar. The sensor exhibited a sensitivity of 127 pm/N and a maximum FSO hysteresis of around ∼0.09 in real-time operation. Very good reliability was achieved when the sensor was utilized for in situ measurements. This study may lead to smart FBG-based amputee stump/socket structures for pressure monitoring in amputee socket systems, which will result in better-designed prosthetic sockets that ensure improved patient satisfaction. PMID:23941909

The capability of fiber Bragg grating sensors to measure amputees' trans-tibial stump/socket interface pressures.

PubMed

Al-Fakih, Ebrahim A; Osman, Noor Azuan Abu; Eshraghi, Arezoo; Adikan, Faisal Rafiq Mahamd

2013-08-12

This study presents the first investigation into the capability of fiber Bragg grating (FBG) sensors to measure interface pressure between the stump and the prosthetic sockets of a trans-tibial amputee. FBG element(s) were recoated with and embedded in a thin layer of epoxy material to form a sensing pad, which was in turn embedded in a silicone polymer material to form a pressure sensor. The sensor was tested in real time by inserting a heavy-duty balloon into the socket and inflating it by using an air compressor. This test was conducted to examine the sensitivity and repeatability of the sensor when subjected to pressure from the stump of the trans-tibial amputee and to mimic the actual environment of the amputee's Patellar Tendon (PT) bar. The sensor exhibited a sensitivity of 127 pm/N and a maximum FSO hysteresis of around ~0.09 in real-time operation. Very good reliability was achieved when the sensor was utilized for in situ measurements. This study may lead to smart FBG-based amputee stump/socket structures for pressure monitoring in amputee socket systems, which will result in better-designed prosthetic sockets that ensure improved patient satisfaction.

Engagement in activities revealing the body and psychosocial adjustment in adults with a trans-tibial prosthesis.

PubMed

Donovan-Hall, M K; Yardley, L; Watts, R J

2002-04-01

The purpose of this study was to examine the effects of the appearance of a prosthesis on social behaviour, social discomfort and psychological well-being in eleven amputees taking delivery of a prosthesis with a silicone cover. Two new scales were developed: the 'Engagement in everyday activities involving revealing the body' (EEARB); and the 'Discomfort-Engagement in everyday activities involving revealing the body' (Discomfort-EEARB) scales. The psychometric properties of these scales were determined using a sample of 101 able-bodied adults. The Hospital Anxiety and Depression Scale and the Rosenberg Self-Esteem Scale were also used to measure psychological well-being in the amputee sample. The EEARB and Discomfort-EEARB proved to have good reliability and validity. Comparison of amputees' scores prior to receiving the silicone cosmesis with those of the able-bodied adults revealed significant behavioural limitations and social discomfort, associated with low self-esteem, anxiety and depression. There was a significant increase in amputees' scores three months afier taking delivery of their prosthesis, indicating that amputees reported engaging in more activities which involved revealing their body, and that they would feel more comfortable in situations which involved revealing the body. As the amputee sample available was small and self-selected, it is not possible to generalise these findings to the amputee population as a whole. However, since there is little previous research investigating the effects of the appearance of the prosthesis, these findings demonstrate the need for further research in this area.

Optimization of prosthetic foot stiffness to reduce metabolic cost and intact knee loading during below-knee amputee walking: a theoretical study.

PubMed

Fey, Nicholas P; Klute, Glenn K; Neptune, Richard R

2012-11-01

Unilateral below-knee amputees develop abnormal gait characteristics that include bilateral asymmetries and an elevated metabolic cost relative to non-amputees. In addition, long-term prosthesis use has been linked to an increased prevalence of joint pain and osteoarthritis in the intact leg knee. To improve amputee mobility, prosthetic feet that utilize elastic energy storage and return (ESAR) have been designed, which perform important biomechanical functions such as providing body support and forward propulsion. However, the prescription of appropriate design characteristics (e.g., stiffness) is not well-defined since its influence on foot function and important in vivo biomechanical quantities such as metabolic cost and joint loading remain unclear. The design of feet that improve these quantities could provide considerable advancements in amputee care. Therefore, the purpose of this study was to couple design optimization with dynamic simulations of amputee walking to identify the optimal foot stiffness that minimizes metabolic cost and intact knee joint loading. A musculoskeletal model and distributed stiffness ESAR prosthetic foot model were developed to generate muscle-actuated forward dynamics simulations of amputee walking. Dynamic optimization was used to solve for the optimal muscle excitation patterns and foot stiffness profile that produced simulations that tracked experimental amputee walking data while minimizing metabolic cost and intact leg internal knee contact forces. Muscle and foot function were evaluated by calculating their contributions to the important walking subtasks of body support, forward propulsion and leg swing. The analyses showed that altering a nominal prosthetic foot stiffness distribution by stiffening the toe and mid-foot while making the ankle and heel less stiff improved ESAR foot performance by offloading the intact knee during early to mid-stance of the intact leg and reducing metabolic cost. The optimal design also provided moderate braking and body support during the first half of residual leg stance, while increasing the prosthesis contributions to forward propulsion and body support during the second half of residual leg stance. Future work will be directed at experimentally validating these results, which have important implications for future designs of prosthetic feet that could significantly improve amputee care.

An Analysis of Intrinsic and Extrinsic Hand Muscle EMG for Improved Pattern Recognition Control.

PubMed

Adewuyi, Adenike A; Hargrove, Levi J; Kuiken, Todd A

2016-04-01

Pattern recognition control combined with surface electromyography (EMG) from the extrinsic hand muscles has shown great promise for control of multiple prosthetic functions for transradial amputees. There is, however, a need to adapt this control method when implemented for partial-hand amputees, who possess both a functional wrist and information-rich residual intrinsic hand muscles. We demonstrate that combining EMG data from both intrinsic and extrinsic hand muscles to classify hand grasps and finger motions allows up to 19 classes of hand grasps and individual finger motions to be decoded, with an accuracy of 96% for non-amputees and 85% for partial-hand amputees. We evaluated real-time pattern recognition control of three hand motions in seven different wrist positions. We found that a system trained with both intrinsic and extrinsic muscle EMG data, collected while statically and dynamically varying wrist position increased completion rates from 73% to 96% for partial-hand amputees and from 88% to 100% for non-amputees when compared to a system trained with only extrinsic muscle EMG data collected in a neutral wrist position. Our study shows that incorporating intrinsic muscle EMG data and wrist motion can significantly improve the robustness of pattern recognition control for application to partial-hand prosthetic control.

An Analysis of Intrinsic and Extrinsic Hand Muscle EMG for Improved Pattern Recognition Control

PubMed Central

Adewuyi, Adenike A.; Hargrove, Levi J.; Kuiken, Todd A.

2015-01-01

Pattern recognition control combined with surface electromyography (EMG) from the extrinsic hand muscles has shown great promise for control of multiple prosthetic functions for transradial amputees. There is, however, a need to adapt this control method when implemented for partial-hand amputees, who possess both a functional wrist and information-rich residual intrinsic hand muscles. We demonstrate that combining EMG data from both intrinsic and extrinsic hand muscles to classify hand grasps and finger motions allows up to 19 classes of hand grasps and individual finger motions to be decoded, with an accuracy of 96% for non-amputees and 85% for partial-hand amputees. We evaluated real-time pattern recognition control of three hand motions in seven different wrist positions. We found that a system trained with both intrinsic and extrinsic muscle EMG data, collected while statically and dynamically varying wrist position increased completion rates from 73% to 96% for partial-hand amputees and from 88% to 100% for non-amputees when compared to a system trained with only extrinsic muscle EMG data collected in a neutral wrist position. Our study shows that incorporating intrinsic muscle EMG data and wrist motion can significantly improve the robustness of pattern recognition control for partial-hand applications. PMID:25955989

Atypical electrophysiological activity during pain observation in amputees who experience synaesthetic pain.

PubMed

Fitzgibbon, Bernadette M; Enticott, Peter G; Giummarra, Melita J; Thomson, Richard H; Georgiou-Karistianis, Nellie; Bradshaw, John L

2012-03-01

There are increasing reports of people experiencing pain when observing pain in another. This describes the phenomenon of synaesthetic pain which, until recently, had been primarily reported in amputees with phantom pain. In the current study, we used electroencephalography (EEG) to investigate how amputees who experience synaesthetic pain process pain observed in another. Participants were grouped according to amputees who experience phantom and synaesthetic pain (n=8), amputees who experience phantom pain but not synaesthetic pain (n=10) and healthy controls (n=10). Participants underwent EEG as they observed still images of hands and feet in potentially painful and non-painful situations. We found that pain synaesthetes showed some reduced event-related potential (ERP) components at certain electrode sites, and reduced theta- and alpha band power amplitude at a central electrode. The finding of reduced ERP amplitude and theta band power may reflect inhibition of the processing of observed pain (e.g. avoidance/guarding as a protective strategy), and reduced alpha band power may indicate a disinhibition in control processes that may result in synaesthetic pain. These results provide the first documentation of atypical neurophysiological activity in amputees who experience synaesthetic pain when processing pain in another. © The Author (2011). Published by Oxford University Press.

Factors Associated with Prosthetic Looseness in Lower Limb Amputees.

PubMed

Phonghanyudh, Thong; Sutpasanon, Taweesak; Hathaiareerug, Chanasak; Devakula, M L Buddhibongsa; Kumnerddee, Wipoo

2015-12-01

To determine the factors associated with prosthetic looseness in lower limb amputees in Sisaket province. The present was a cross-sectional descriptive study. Subjects were lower limb amputees who previously obtained prostheses and required prosthetic replacements at the mobile prosthetic laboratory unit under the Prostheses Foundation of H.R.H. the Princess Mother at Khun Han Hospital, Sisaket province, in February 2013. Data including participant characteristics, prosthetic looseness data, and various variables were collected by direct semi-structured interview. Energy expenditures in physical activities were measured using the Thai version of the short format international physical activity questionnaire. Data between participants with and without prosthetic looseness were compared to determine prosthetic loosening associated factors. Among 101 participants enrolled, 33 (32.7%) had prosthetic looseness with average onset of 1.76 ± 1.67 years. Diabetes mellitus was the only significant factor associated with prosthetic looseness from both univariate and multivariate analyses (HR = 7.05, p = 0.002 and HR = 5.93, p = 0.007 respectively). Among the lower limb amputees in Sisaket province, diabetes mellitus was the only factor associated with prosthetic looseness. Therefore, diabetic screening should be supplemented in lower limb amputee assessment protocol. In addition, we recommend that amputees with diabetes mellitus should receive prosthesis check out at approximately

Determinants of skin problems of the stump in lower-limb amputees.

PubMed

Meulenbelt, Henk E; Geertzen, Jan H; Jonkman, Marcel F; Dijkstra, Pieter U

2009-01-01

To identify determinants of skin problems in lower-limb amputees. Survey, using a questionnaire. Not applicable. Lower-limb amputees (N=2039) who either obtained their prosthesis through the Orthopedische Instrument Makerij (a group of orthopedic workshops in the Netherlands) or were a member of the (Dutch) National Society of Amputees (Landelijke Vereniging van Geamputeerden) were invited to participate. In total, 872 lower-limb amputees agreed to participate. Amputees filled in the questionnaire to assess characteristics of the amputation and prosthesis, level of activity, stump and prosthesis hygiene, and skin problems. Stepwise backward logistic regression was performed to analyze determinants of skin problems. Skin problems in the month prior to completing the questionnaire. A total of 816 questionnaires were received. Eventually 805 questionnaires were suitable for statistical analysis. Protective determinants were (in order of magnitude of association) older age, male sex, and amputation because of peripheral arterial disease and/or diabetes. Provocative determinants were (in order of magnitude of association) use of antibacterial soap, smoking, and washing the stump 4 times a week or more often. In total, 63% of the participants (95% confidence interval, 60%-67%) reported 1 or more skin problems. The provocative determinants identified in this study--use of antibacterial soap, smoking, and stump washing frequency--have to be studied for their clinical relevance.

Systematic variation of prosthetic foot spring affects center-of-mass mechanics and metabolic cost during walking.

PubMed

Zelik, Karl E; Collins, Steven H; Adamczyk, Peter G; Segal, Ava D; Klute, Glenn K; Morgenroth, David C; Hahn, Michael E; Orendurff, Michael S; Czerniecki, Joseph M; Kuo, Arthur D

2011-08-01

Lower-limb amputees expend more energy to walk than non-amputees and have an elevated risk of secondary disabilities. Insufficient push-off by the prosthetic foot may be a contributing factor. We aimed to systematically study the effect of prosthetic foot mechanics on gait, to gain insight into fundamental prosthetic design principles. We varied a single parameter in isolation, the energy-storing spring in a prototype prosthetic foot, the controlled energy storage and return (CESR) foot, and observed the effect on gait. Subjects walked on the CESR foot with three different springs. We performed parallel studies on amputees and on non-amputees wearing prosthetic simulators. In both groups, spring characteristics similarly affected ankle and body center-of-mass (COM) mechanics and metabolic cost. Softer springs led to greater energy storage, energy return, and prosthetic limb COM push-off work. But metabolic energy expenditure was lowest with a spring of intermediate stiffness, suggesting biomechanical disadvantages to the softest spring despite its greater push-off. Disadvantages of the softest spring may include excessive heel displacements and COM collision losses. We also observed some differences in joint kinetics between amputees and non-amputees walking on the prototype foot. During prosthetic push-off, amputees exhibited reduced energy transfer from the prosthesis to the COM along with increased hip work, perhaps due to greater energy dissipation at the knee. Nevertheless, the results indicate that spring compliance can contribute to push-off, but with biomechanical trade-offs that limit the degree to which greater push-off might improve walking economy. © 2011 IEEE

Systematic variation of prosthetic foot spring affects center-of-mass mechanics and metabolic cost during walking

PubMed Central

Zelik, Karl E.; Collins, Steven H.; Adamczyk, Peter G.; Segal, Ava D.; Klute, Glenn K.; Morgenroth, David C.; Hahn, Michael E.; Orendurff, Michael S.; Czerniecki, Joseph M.; Kuo, Arthur D.

2014-01-01

Lower-limb amputees expend more energy to walk than non-amputees and have an elevated risk of secondary disabilities. Insufficient push-off by the prosthetic foot may be a contributing factor. We aimed to systematically study the effect of prosthetic foot mechanics on gait, to gain insight into fundamental prosthetic design principles. We varied a single parameter in isolation, the energy-storing spring in a prototype prosthetic foot, the Controlled Energy Storage and Return (CESR) foot, and observed the effect on gait. Subjects walked on the CESR foot with three different springs. We performed parallel studies on amputees and on non-amputees wearing prosthetic simulators. In both groups, spring characteristics similarly affected ankle and body center-of-mass (COM) mechanics and metabolic cost. Softer springs led to greater energy storage, energy return and prosthetic limb COM push-off work. But metabolic energy expenditure was lowest with a spring of intermediate stiffness, suggesting biomechanical disadvantages to the softest spring despite its greater push-off. Disadvantages of the softest spring may include excessive heel displacements and COM collision losses. We also observed some differences in joint kinetics between amputees and non-amputees walking on the prototype foot. During prosthetic push-off, amputees exhibited reduced energy transfer from the prosthesis to the COM along with increased hip work, perhaps due to greater energy dissipation at the knee. Nevertheless, the results indicate that spring compliance can contribute to push-off, but with biomechanical trade-offs that limit the degree to which greater push-off might improve walking economy. PMID:21708509

Electro-cutaneous stimulation on the palm elicits referred sensations on intact but not on amputated digits

NASA Astrophysics Data System (ADS)

D'Alonzo, M.; Engels, L. F.; Controzzi, M.; Cipriani, C.

2018-02-01

Objective. Grasping and manipulation control critically depends on tactile feedback. Without this feedback, the ability for fine control of a prosthesis is limited in upper limb amputees. Early studies have shown that non-invasive electro-cutaneous stimulation (ES) can induce referred sensations that are spread to a wider and/or more distant area, with respect to the electrodes. Building on this, we sought to exploit this effect to provide somatotopically matched sensory feedback to people with partial hand (digital) amputations. Approach. For the first time, this work investigated the possibility of inducing referred sensations in the digits by activating the palmar nerves. Specifically, we electrically stimulated 18 sites on the palm of non-amputees to evaluate the effects of sites and stimulation parameters on modality, magnitude, and location of the evoked sensations. We performed similar tests with partial hand amputees by testing those sites that had most consistently elicited referred sensations in non-amputees. Main results. We demonstrated referred sensations in non-amputees from all stimulation sites in one form or another. Specifically, the stimulation of 16 of the 18 sites gave rise to reliable referred sensations. Amputees experienced referred sensations to unimpaired digits, just like non-amputees, but we were unable to evoke referred sensations in their missing digits: none of them reported sensations that extended beyond the tip of the stump. Significance. The possibility of eliciting referred sensations on the digits may be exploited in haptic systems for providing touch sensations without obstructing the fingertips or their movements. The study also suggests that the phenomenon of referred sensations through ES may not be exploited for partial hand prostheses, and it invites researchers to explore alternative approaches. Finally, the results seem to confirm previous studies suggesting that the stumps in partial hand amputees partially acquire the role of the missing fingertips, physiologically and cognitively.

Magnetic resonance spectroscopy of current hand amputees reveals evidence for neuronal-level changes in former sensorimotor cortex

PubMed Central

Choi, In-Young; Lee, Phil; Peng, Huiling; Kaufman, Christina L.; Frey, Scott H.

2017-01-01

Deafferentation is accompanied by large-scale functional reorganization of maps in the primary sensory and motor areas of the hemisphere contralateral to injury. Animal models of deafferentation suggest a variety of cellular-level changes including depression of neuronal metabolism and even neuronal death. Whether similar neuronal changes contribute to patterns of reorganization within the contralateral sensorimotor cortex of chronic human amputees is uncertain. We used functional MRI-guided proton magnetic resonance spectroscopy to test the hypothesis that unilateral deafferentation is associated with lower levels of N-acetylaspartate (NAA, a putative marker of neuronal integrity) in the sensorimotor hand territory located contralateral to the missing hand in chronic amputees (n = 19) compared with the analogous hand territory of age- and sex-matched healthy controls (n = 28). We also tested whether former amputees [i.e., recipients of replanted (n = 3) or transplanted (n = 2) hands] exhibit NAA levels that are indistinguishable from controls, possible evidence for reversal of the effects of deafferentation. As predicted, relative to controls, current amputees exhibited lower levels of NAA that were negatively and significantly correlated with the time after amputation. Contrary to our prediction, NAA levels in both replanted and transplanted patients fell within the range of the current amputees. We suggest that lower levels of NAA in current amputees reflects altered neuronal integrity consequent to chronic deafferentation. Thus local changes in NAA levels may provide a means of assessing neuroplastic changes in deafferented cortex. Results from former amputees suggest that these changes may not be readily reversible through reafferentation. NEW & NOTEWORTHY This study is the first to use functional magnetic resonance-guided magnetic resonance spectroscopy to examine neurochemical mechanisms underlying functional reorganization in the primary somatosensory and motor cortices consequent to upper extremity amputation and its potential reversal through hand replantation or transplantation. We provide evidence for selective alteration of cortical neuronal integrity associated with amputation-related deafferentation that may not be reversible. PMID:28179478

Voluntary Control of Residual Antagonistic Muscles in Transtibial Amputees: Feedforward Ballistic Contractions and Implications for Direct Neural Control of Powered Lower Limb Prostheses.

PubMed

Huang, Stephanie; Huang, He

2018-04-01

Discrete, rapid (i.e., ballistic like) muscle activation patterns have been observed in ankle muscles (i.e., plantar flexors and dorsiflexors) of able-bodied individuals during voluntary posture control. This observation motivated us to investigate whether transtibial amputees are capable of generating such a ballistic-like activation pattern accurately using their residual ankle muscles in order to assess whether the volitional postural control of a powered ankle prosthesis using proportional myoelectric control via residual muscles could be feasible. In this paper, we asked ten transtibial amputees to generate ballistic-like activation patterns using their residual lateral gastrocnemius and residual tibialis anterior to control a computer cursor via proportional myoelectric control to hit targets positioned at 20% and 40% of maximum voluntary contraction of the corresponding residual muscle. During practice conditions, we asked amputees to hit a single target repeatedly. During testing conditions, we asked amputees to hit a random sequence of targets. We compared movement time to target and end-point accuracy. We also examined motor recruitment synchronization via time-frequency representations of residual muscle activation. The result showed that median end-point error ranged from -0.6% to 1% maximum voluntary contraction across subjects during practice, which was significantly lower compared to testing ( ). Average movement time for all amputees was 242 ms during practice and 272 ms during testing. Motor recruitment synchronization varied across subjects, and amputees with the highest synchronization achieved the fastest movement times. End-point accuracy was independent of movement time. Results suggest that it is feasible for transtibial amputees to generate ballistic control signals using their residual muscles. Future work on volitional control of powered power ankle prostheses might consider anticipatory postural control based on ballistic-like residual muscle activation patterns and direct continuous proportional myoelectric control.

Predict the Medicare Functional Classification Level (K-level) using the Amputee Mobility Predictor in people with unilateral transfemoral and transtibial amputation: A pilot study.

PubMed

Dillon, Michael P; Major, Matthew J; Kaluf, Brian; Balasanov, Yuri; Fatone, Stefania

2018-04-01

While Amputee Mobility Predictor scores differ between Medicare Functional Classification Levels (K-level), this does not demonstrate that the Amputee Mobility Predictor can accurately predict K-level. To determine how accurately K-level could be predicted using the Amputee Mobility Predictor in combination with patient characteristics for persons with transtibial and transfemoral amputation. Prediction. A cumulative odds ordinal logistic regression was built to determine the effect that the Amputee Mobility Predictor, in combination with patient characteristics, had on the odds of being assigned to a particular K-level in 198 people with transtibial or transfemoral amputation. For people assigned to the K2 or K3 level by their clinician, the Amputee Mobility Predictor predicted the clinician-assigned K-level more than 80% of the time. For people assigned to the K1 or K4 level by their clinician, the prediction of clinician-assigned K-level was less accurate. The odds of being in a higher K-level improved with younger age and transfemoral amputation. Ordinal logistic regression can be used to predict the odds of being assigned to a particular K-level using the Amputee Mobility Predictor and patient characteristics. This pilot study highlighted critical method design issues, such as potential predictor variables and sample size requirements for future prospective research. Clinical relevance This pilot study demonstrated that the odds of being assigned a particular K-level could be predicted using the Amputee Mobility Predictor score and patient characteristics. While the model seemed sufficiently accurate to predict clinician assignment to the K2 or K3 level, further work is needed in larger and more representative samples, particularly for people with low (K1) and high (K4) levels of mobility, to be confident in the model's predictive value prior to use in clinical practice.

Studying Upper-Limb Amputee Prosthesis Use to Inform Device Design

DTIC Science & Technology

2017-10-01

AWARD NUMBER: W81XWH-14-1-0277 TITLE: Studying Upper-Limb Amputee Prosthesis Use to Inform Device Design PRINCIPAL INVESTIGATOR: Aaron...Department of the Army position, policy or decision unless so designated by other documentation. REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704...Amputee Prosthesis Use to Inform Device Design 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Aaron Dollar, Adam Spiers

The effects of a controlled energy storage and return prototype prosthetic foot on transtibial amputee ambulation

PubMed Central

Segal, Ava D.; Zelik, Karl E.; Klute, Glenn K.; Morgenroth, David C.; Hahn, Michael E.; Orendurff, Michael S.; Adamczyk, Peter G.; Collins, Steven H.; Kuo, Arthur D.; Czerniecki, Joseph M.

2015-01-01

The lack of functional ankle musculature in lower limb amputees contributes to the reduced prosthetic ankle push-off, compensations at other joints and more energetically costly gait commonly observed in comparison to non-amputees. A variety of energy storing and return prosthetic feet have been developed to address these issues but have not been shown to sufficiently improve amputee biomechanics and energetic cost, perhaps because the timing and magnitude of energy return is not controlled. The goal of this study was to examine how a prototype microprocessor-controlled prosthetic foot designed to store some of the energy during loading and return it during push-off affects amputee gait. Unilateral transtibial amputees wore the Controlled Energy Storage and Return prosthetic foot (CESR), a conventional foot (CONV), and their previously prescribed foot (PRES) in random order. Three-dimensional gait analysis and net oxygen consumption were collected as participants walked at constant speed. The CESR foot demonstrated increased energy storage during early stance, increased prosthetic foot peak push-off power and work, increased prosthetic limb center of mass (COM) push-off work and decreased intact limb COM collision work compared to CONV and PRES. The biological contribution of the positive COM work for CESR was reduced compared to CONV and PRES. However, the net metabolic cost for CESR did not change compared to CONV and increased compared to PRES, which may partially reflect the greater weight, lack of individualized size and stiffness and relatively less familiarity for CESR and CONV. Controlled energy storage and return enhanced prosthetic push-off, but requires further design modifications to improve amputee walking economy. PMID:22100728

A biomechanical analysis of the long-jump technique of elite female amputee athletes.

PubMed

Nolan, Lee; Patritti, Benjamin L; Simpson, Kathy J

2006-10-01

The purpose of this study was to investigate whether female lower-limb amputees conform to the established long-jump model and to compare the kinematics of the approach and take-off phases for elite female transfemoral and transtibial amputee long jumpers. Eight female transfemoral and nine female transtibial amputee athletes were videotaped (sagittal plane movements at 50 Hz) from third-to-last step to take-off during the 2004 Paralympic Games long-jump finals. After digitizing and reconstruction of 2D coordinates, key variables were calculated at each stride and during contact with the take-off board. Additionally, approach speed during the run-up of each jump was recorded (100 Hz) using a laser Doppler device (LDM 300 C Sport, Jenoptik Laser, Jena, Germany). The transfemoral amputees had a consistently higher center of mass height on the last three steps before take-off than the transtibial amputees. However, at touch-down onto the take-off board, they lowered their center of mass excessively so that from touch-down to take-off, they were actually lower than the transtibial amputees. This resulted in a greater negative vertical velocity at touch-down and may have inversely affected their jump performance. Female transtibial athletes conformed to the long-jump model, although adaptations to this technique were displayed. Female transfemoral athletes, however, exhibited no relationship between take-off speed and distance jumped, which may be attributable to their excessive lowering of their center-of-mass height at touch-down onto the take-off board. It is recommended that coaches and athletes proceed with caution when trying to replicate techniques used by able-bodied athletes because adaptations to the constraints of a prosthesis should be considered.

The effects of a controlled energy storage and return prototype prosthetic foot on transtibial amputee ambulation.

PubMed

Segal, Ava D; Zelik, Karl E; Klute, Glenn K; Morgenroth, David C; Hahn, Michael E; Orendurff, Michael S; Adamczyk, Peter G; Collins, Steven H; Kuo, Arthur D; Czerniecki, Joseph M

2012-08-01

The lack of functional ankle musculature in lower limb amputees contributes to the reduced prosthetic ankle push-off, compensations at other joints and more energetically costly gait commonly observed in comparison to non-amputees. A variety of energy storing and return prosthetic feet have been developed to address these issues but have not been shown to sufficiently improve amputee biomechanics and energetic cost, perhaps because the timing and magnitude of energy return is not controlled. The goal of this study was to examine how a prototype microprocessor-controlled prosthetic foot designed to store some of the energy during loading and return it during push-off affects amputee gait. Unilateral transtibial amputees wore the Controlled Energy Storage and Return prosthetic foot (CESR), a conventional foot (CONV), and their previously prescribed foot (PRES) in random order. Three-dimensional gait analysis and net oxygen consumption were collected as participants walked at constant speed. The CESR foot demonstrated increased energy storage during early stance, increased prosthetic foot peak push-off power and work, increased prosthetic limb center of mass (COM) push-off work and decreased intact limb COM collision work compared to CONV and PRES. The biological contribution of the positive COM work for CESR was reduced compared to CONV and PRES. However, the net metabolic cost for CESR did not change compared to CONV and increased compared to PRES, which may partially reflect the greater weight, lack of individualized size and stiffness and relatively less familiarity for CESR and CONV. Controlled energy storage and return enhanced prosthetic push-off, but requires further design modifications to improve amputee walking economy. Published by Elsevier B.V.

Localizing and Assessing Amputee Pain with Intense Focused Ultrasound

DTIC Science & Technology

2016-10-01

the nerve and then implants it into nearby muscle. TMR surgery has anecdotal evidence of reduced pain for amputees relative to standard amputee...Neuropathic Pain Is Present in Chronic Low Back Pain and Soft Tissue Syndromes? An Evidence - Based Structured Review. Pain Med. 2014 Jan 1;15(1):4–15...scar tissue at the end of cut nerves that then applies pressure to the nerve ending. In addition, traditional amputation surgery almost always produces

Application of real-time machine learning to myoelectric prosthesis control: A case series in adaptive switching.

PubMed

Edwards, Ann L; Dawson, Michael R; Hebert, Jacqueline S; Sherstan, Craig; Sutton, Richard S; Chan, K Ming; Pilarski, Patrick M

2016-10-01

Myoelectric prostheses currently used by amputees can be difficult to control. Machine learning, and in particular learned predictions about user intent, could help to reduce the time and cognitive load required by amputees while operating their prosthetic device. The goal of this study was to compare two switching-based methods of controlling a myoelectric arm: non-adaptive (or conventional) control and adaptive control (involving real-time prediction learning). Case series study. We compared non-adaptive and adaptive control in two different experiments. In the first, one amputee and one non-amputee subject controlled a robotic arm to perform a simple task; in the second, three able-bodied subjects controlled a robotic arm to perform a more complex task. For both tasks, we calculated the mean time and total number of switches between robotic arm functions over three trials. Adaptive control significantly decreased the number of switches and total switching time for both tasks compared with the conventional control method. Real-time prediction learning was successfully used to improve the control interface of a myoelectric robotic arm during uninterrupted use by an amputee subject and able-bodied subjects. Adaptive control using real-time prediction learning has the potential to help decrease both the time and the cognitive load required by amputees in real-world functional situations when using myoelectric prostheses. © The International Society for Prosthetics and Orthotics 2015.

Robotic touch shifts perception of embodiment to a prosthesis in targeted reinnervation amputees

PubMed Central

Kim, Keehoon; Colgate, James Edward; Peshkin, Michael A.; Kuiken, Todd A.

2011-01-01

Existing prosthetic limbs do not provide amputees with cutaneous feedback. Tactile feedback is essential to intuitive control of a prosthetic limb and it is now clear that the sense of body self-identification is also linked to cutaneous touch. Here we have created an artificial sense of touch for a prosthetic limb by coupling a pressure sensor on the hand through a robotic stimulator to surgically redirected cutaneous sensory nerves (targeted reinnervation) that once served the lost limb. We hypothesize that providing physiologically relevant cutaneous touch feedback may help an amputee incorporate an artificial limb into his or her self image. To investigate this we used a robotic touch interface coupled with a prosthetic limb and tested it with two targeted reinnervation amputees in a series of experiments fashioned after the Rubber Hand Illusion. Results from both subjective (self-reported) and objective (physiological) measures of embodiment (questionnaires, psychophysical temporal order judgements and residual limb temperature measurements) indicate that returning physiologically appropriate cutaneous feedback from a prosthetic limb drives a perceptual shift towards embodiment of the device for these amputees. Measurements provide evidence that the illusion created is vivid. We suggest that this may help amputees to more effectively incorporate an artificial limb into their self image, providing the possibility that a prosthesis becomes not only a tool, but also an integrated body part. PMID:21252109

Crowd-Sourced Amputee Gait Data: A Feasibility Study Using YouTube Videos of Unilateral Trans-Femoral Gait.

PubMed

Gardiner, James; Gunarathne, Nuwan; Howard, David; Kenney, Laurence

2016-01-01

Collecting large datasets of amputee gait data is notoriously difficult. Additionally, collecting data on less prevalent amputations or on gait activities other than level walking and running on hard surfaces is rarely attempted. However, with the wealth of user-generated content on the Internet, the scope for collecting amputee gait data from alternative sources other than traditional gait labs is intriguing. Here we investigate the potential of YouTube videos to provide gait data on amputee walking. We use an example dataset of trans-femoral amputees level walking at self-selected speeds to collect temporal gait parameters and calculate gait asymmetry. We compare our YouTube data with typical literature values, and show that our methodology produces results that are highly comparable to data collected in a traditional manner. The similarity between the results of our novel methodology and literature values lends confidence to our technique. Nevertheless, clear challenges with the collection and interpretation of crowd-sourced gait data remain, including long term access to datasets, and a lack of validity and reliability studies in this area.

Crowd-Sourced Amputee Gait Data: A Feasibility Study Using YouTube Videos of Unilateral Trans-Femoral Gait

PubMed Central

Gardiner, James; Gunarathne, Nuwan; Howard, David; Kenney, Laurence

2016-01-01

Collecting large datasets of amputee gait data is notoriously difficult. Additionally, collecting data on less prevalent amputations or on gait activities other than level walking and running on hard surfaces is rarely attempted. However, with the wealth of user-generated content on the Internet, the scope for collecting amputee gait data from alternative sources other than traditional gait labs is intriguing. Here we investigate the potential of YouTube videos to provide gait data on amputee walking. We use an example dataset of trans-femoral amputees level walking at self-selected speeds to collect temporal gait parameters and calculate gait asymmetry. We compare our YouTube data with typical literature values, and show that our methodology produces results that are highly comparable to data collected in a traditional manner. The similarity between the results of our novel methodology and literature values lends confidence to our technique. Nevertheless, clear challenges with the collection and interpretation of crowd-sourced gait data remain, including long term access to datasets, and a lack of validity and reliability studies in this area. PMID:27764226

Prosthetic Engineering

MedlinePlus

... torque adapter in the pylons of transtibial amputees. Energy Storage & Release Many ambulatory lower limb amputees exhibit ... Future Directions Current Project Summaries Development of Controlled Energy Storage and Release Prosthetic Foot Development of Inverting- ...

Swarm-wavelet based extreme learning machine for finger movement classification on transradial amputees.

PubMed

Anam, Khairul; Al-Jumaily, Adel

2014-01-01

The use of a small number of surface electromyography (EMG) channels on the transradial amputee in a myoelectric controller is a big challenge. This paper proposes a pattern recognition system using an extreme learning machine (ELM) optimized by particle swarm optimization (PSO). PSO is mutated by wavelet function to avoid trapped in a local minima. The proposed system is used to classify eleven imagined finger motions on five amputees by using only two EMG channels. The optimal performance of wavelet-PSO was compared to a grid-search method and standard PSO. The experimental results show that the proposed system is the most accurate classifier among other tested classifiers. It could classify 11 finger motions with the average accuracy of about 94 % across five amputees.

Administration for Community Living

MedlinePlus

... has been awarded under the… read more New robotic hand named after Luke Skywalker helps amputee touch ... November 15, 2017 Washington Post (November 15) New robotic hand named after Luke Skywalker helps amputee touch ...

Relief of knee flexion contracture and gait improvement following adaptive training for an assist device in a transtibial amputee: A case study.

PubMed

Kim, Sol-Bi; Ko, Chang-Yong; Son, Jinho; Kang, Sungjae; Ryu, Jeicheong; Mun, Museong

2017-01-01

Management of a knee contracture is important for regaining gait ability in transtibial amputees. However, there has been little study of prosthesis training for enhancing mobility and improving range of motion in cases of restricted knee extension. This study aimed to evaluate the effects of adaptive training for an assist device (ATAD) for a transtibial amputee with a knee flexion contracture (KFC). A male transtibial amputee with KFC performed 4 months of ATAD with a multidisciplinary team. During the ATAD, the passive range of motion (PROM) in the knee, amputee mobility predictor (AMP) assessment, center of pressure (COP) on a force plate-equipped treadmill, gait features determined by three-dimensional motion analysis, and Short-Form 36 Item Health Survey (SF-36) scores were evaluated. Following ATAD, PROM showed immediate improvement (135.6 ± 2.4° at baseline, 142.5 ± 1.7° at Step 1, 152.1 ± 1.8° at Step 2, 165.8 ± 1.9° at Step 3, and 166.0 ± 1.4° at Step 4); this was followed by an enhanced COP. Gradually, gait features also improved. Additionally, the AMP score (5 at baseline to 29 at Step 4) and K-level (K0 at baseline to K3 at Step 4) increased after ATAD. Along with these improvements, the SF-36 score also improved. ATAD could be beneficial for transtibial amputees by relieving knee contractures and improving gait.

Intention detection of gait initiation using EMG and kinematic data.

PubMed

Wentink, E C; Beijen, S I; Hermens, H J; Rietman, J S; Veltink, P H

2013-02-01

Gait initiation in transfemoral amputees (TFA) is different from non-amputees. This is mainly caused by the lack of stability and push-off from the prosthetic leg. Adding control and artificial push-off to the prosthesis may therefore be beneficial to TFA. In this study the feasibility of real-time intention detection of gait initiation was determined by mimicking the TFA situation in non-amputees. EMG and inertial sensor data was measured in 10 non-amputees. Only data available in TFA was used to determine if gait initiation can be predicted in time to control a transfemoral prosthesis to generate push-off and stability. Toe-off and heel-strike of the leading limb are important parameters to be detected, to control a prosthesis and to time push-off. The results show that toe-off and heel-strike of the leading limb can be detected using EMG and kinematic data in non-amputees 130-260 ms in advance. This leaves enough time to control a prosthesis. Based on these results we hypothesize that similar results can be found in TFA, allowing for adequate control of a prosthesis during gait initiation. Copyright © 2012 Elsevier B.V. All rights reserved.

Phantom somatosensory evoked potentials following selective intraneural electrical stimulation in two amputees.

PubMed

Granata, Giuseppe; Di Iorio, Riccardo; Romanello, Roberto; Iodice, Francesco; Raspopovic, Stanisa; Petrini, Francesco; Strauss, Ivo; Valle, Giacomo; Stieglitz, Thomas; Čvančara, Paul; Andreu, David; Divoux, Jean-Louis; Guiraud, David; Wauters, Loic; Hiairrassary, Arthur; Jensen, Winnie; Micera, Silvestro; Rossini, Paolo Maria

2018-06-01

The aim of the paper is to objectively demonstrate that amputees implanted with intraneural interfaces are truly able to feel a sensation in the phantom hand by recording "phantom" somatosensory evoked potentials from the corresponding brain areas. We implanted four transverse intrafascicular multichannel electrodes, available with percutaneous connections to a multichannel electrical stimulator, in the median and ulnar nerves of two left trans-radial amputees. Two channels of the implants that were able to elicit sensations during intraneural nerve stimulation were chosen, in both patients, for recording somatosensory evoked potentials. We recorded reproducible evoked responses by stimulating the median and the ulnar nerves in both cases. Latencies were in accordance with the arrival of somatosensory information to the primary somatosensory cortex. Our results provide evidence that sensations generated by intraneural stimulation are truly perceived by amputees and located in the phantom hand. Moreover, our results strongly suggest that sensations perceived in different parts of the phantom hand result in different evoked responses. Somatosensory evoked potentials obtained by selective intraneural electrical stimulation in amputee patients are a useful tool to provide an objective demonstration of somatosensory feedback in new generation bidirectional prostheses. Copyright © 2018. Published by Elsevier B.V.

Piezoelectric Bimorphs' Characteristics as In-Socket Sensors for Transfemoral Amputees

PubMed Central

El-Sayed, Amr M.; Hamzaid, Nur Azah; Osman, Noor Azuan Abu

2014-01-01

Alternative sensory systems for the development of prosthetic knees are being increasingly highlighted nowadays, due to the rapid advancements in the field of lower limb prosthetics. This study presents the use of piezoelectric bimorphs as in-socket sensors for transfemoral amputees. An Instron machine was used in the calibration procedure and the corresponding output data were further analyzed to determine the static and dynamic characteristics of the piezoelectric bimorph. The piezoelectric bimorph showed appropriate static operating range, repeatability, hysteresis, and frequency response for application in lower prosthesis, with a force range of 0–100 N. To further validate this finding, an experiment was conducted with a single transfemoral amputee subject to measure the stump/socket pressure using the piezoelectric bimorph embedded inside the socket. The results showed that a maximum interface pressure of about 27 kPa occurred at the anterior proximal site compared to the anterior distal and posterior sites, consistent with values published in other studies. This paper highlighted the capacity of piezoelectric bimorphs to perform as in-socket sensors for transfemoral amputees. However, further experiments are recommended to be conducted with different amputees with different socket types. PMID:25513823

Bariatric amputee: A growing problem?

PubMed

Kulkarni, Jai; Hannett, Dominic P; Purcell, Steven

2015-06-01

This study reviewed prevalence of patients with lower limb amputations with above normal weight profile, with body mass index over 25, in seven disablement services centres managing their amputee rehabilitation in the United Kingdom. To review two clinical standards of practice in amputee rehabilitation. Ambulant lower limb amputees should have their body weight recorded on an electronic information system, with identification of cohort with body weight >100 kg. Lower limb amputees to be provided with suitable weight-rated prosthesis. Observational study of clinical practice. Data were collected from the Clinical Information Management Systems. Inclusion criteria--subjects were ambulant prosthetic users with some prosthetic intervention in the last 5 years and had at least one lower limb amputation. In 96% of patients, the weight record profile was maintained. In addition, 86% were under 100 kg, which is the most common weight limit of prosthetic componentry. Of 15,204 amputation levels, there were 1830 transfemoral and transtibial sites in users with body weight over 100 kg. In 60 cases, the prosthetic limb build was rated to be below the user body weight. In 96% of our patients, body weight was documented, and in 97%, the prosthetic limb builds were within stated body weight limits, but this may not be the case in all the other disablement services centres in the United Kingdom. Also, the incidence of obesity in the United Kingdom is a growing problem, and the health issues associated with obesity are further compounded in the amputee population. Prosthetic componentry has distinct weight limits which must be considered during prescription. As people with amputation approach the limits of specific components, clinicians are faced with the challenge of continued provision in a safe and suitable manner. This article reviews the amputee population and the current national profile to consider trends in provision and the incidence of these challenges. © The International Society for Prosthetics and Orthotics 2014.

Skin problems of the stump in lower limb amputees: 1. A clinical study.

PubMed

Meulenbelt, Henk E J; Geertzen, Jan H B; Jonkman, Marcel F; Dijkstra, Pieter U

2011-03-01

Use of a prosthesis in lower limb amputees can lead to skin problems of the amputation stump. However, little is known about the epidemiology and type of problems experienced. We conducted a cross-sectional survey consisting of a questionnaire and a clinical assessment of the amputation stump. The aims of the study were to estimate the prevalence of skin problems of the amputation stump, to evaluate the impact of these skin problems and to evaluate differences between clinically observed skin problems and skin problems reported by the amputee. Participants (n = 124) were recruited from among lower limb amputees who visited an orthopaedic workshop. The prevalence of skin problems was 36%. Problems identified were: reduction in prosthesis use, and reduction in walking distance without a break. Significantly more skin problems were reported than observed (p = 0.011). Cold skin and excessive perspiration in particular were significantly more reported than observed.

A wearable skin stretch haptic feedback device: Towards improving balance control in lower limb amputees.

PubMed

Husman, M A B; Maqbool, H F; Awad, M I; Abouhossein, A; Dehghani-Sanij, A A

2016-08-01

Haptic feedback to lower limb amputees is essential to maximize the functionality of a prosthetic device by providing information to the user about the interaction with the environment and the position of the prostheses in space. Severed sensory pathway and the absence of connection between the prosthesis and the Central Nervous System (CNS) after lower limb amputation reduces balance control, increases visual dependency and increases risk of falls among amputees. This work describes the design of a wearable haptic feedback device for lower limb amputees using lateral skin-stretch modality intended to serve as a feedback cue during ambulation. A feedback scheme was proposed based on gait event detection for possible real-time postural adjustment. Preliminary perceptual test with healthy subjects in static condition was carried out and the results indicated over 98% accuracy in determining stimuli location around the upper leg region, suggesting good perceptibility of the delivered stimuli.

Combat amputees' health-related quality of life and psychological outcomes: A brief report from the wounded warrior recovery project.

PubMed

Woodruff, Susan I; Galarneau, Michael R; Sack, Daniel I; McCabe, Cameron T; Dye, Judy L

2017-03-01

This study extends what is known about long-term health-related quality of life (HrQoL) and other psychosocial outcomes (i.e., depression, posttraumatic stress disorder [PTSD]) among US military combat amputees serving in Operation Enduring Freedom, Operation Iraqi Freedom, and Operation New Dawn. A total of 63 combat amputees were identified from the Wounded Warrior Recovery Project, a study assessing long-term self-reported HrQoL and psychological outcomes among those wounded during military service. Another 477 service members from the Wounded Warrior Recovery Project were identified as a comparison group (i.e., nonamputees with moderate to severe extremity injuries). After adjusting for age, time since injury, overall injury severity, and traumatic brain injury, amputees had poorer functional HrQoL than those in the nonamputee comparison group overall and in the specific area related to performance of usual activities, and, to some degree, chronic and acute symptoms, and mobility/self-care. On the other hand, depression and PTSD symptoms were not different for the two groups. Results suggest that when assessed over 5 years postinjury, on average, amputees have unique physical and functional limitations, yet do not report greater depression or PTSD symptoms than others seriously injured in combat. It may be that state-of-the-art integrated amputee care that includes support networks and emphasis on adjustment and psychological health may increase successful coping and adjustment, at least to a level that is on par with other types of serious combat injury. Epidemiologic/prognostic study, level III.

Phantom radiculitis effectively treated by fluoroscopically guided transforaminal epidural steroid injections.

PubMed

DeGregoris, Gerard; Diwan, Sudhir

2010-01-01

Lower back and extremity pain in the amputee patient can be challenging to classify and treat. Radicular compression in a patient with lower limb amputation may present as or be superimposed upon phantom limb pain, creating diagnostic difficulties. Both patients and physicians classically find it difficult to discern phantom sensation from phantom limb pain and stump pain; radicular compression is often not considered. Many studies have shown back pain to be a significant cause of pain in lower limb amputees, but sciatica has been rarely reported in amputees. We present a case of L4/5 radiculitis in an above-knee amputee presenting as phantom radiculitis. Our patient is a 67 year old gentleman with new onset 10/10 pain in a phantom extremity superimposed upon a 40 year history of previously stable phantom limb pain. MRI showed a central disc herniation at L4/5 with compression of the traversing left L4 nerve root. Two fluoroscopically guided left transforaminal epidural steroid injections at the level of the L4 and L5 spinal nerve roots totally alleviated his new onset pain. At one year post injection, his phantom radiculitis pain was completely gone, though his underlying phantom limb pain remained. Lumbar radiculitis in lower extremity amputee patients may be difficult to differentiate from baseline phantom limb pain. When conservative techniques fail, fluoroscopically guided spinal nerve injection may be valuable in determining the etiology of lower extremity pain. Our experience supports the notion that epidural steroid injections can effectively treat phantom lumbar radiculitis in lower extremity amputees.

Incidence and morbidity of concomitant spine fractures in combat-related amputees.

PubMed

Bevevino, Adam J; Lehman, Ronald A; Tintle, Scott M; Kang, Daniel G; Dworak, Theodora C; Potter, Benjamin K

2014-04-01

High-energy blasts are the most frequent cause of combat-related amputations in Operations Iraqi and Enduring Freedom (OIF/OEF). The nondiscriminating effects of this mechanism often result in both appendicular and axial skeletal injuries. Despite this recognized coincident injury pattern, the incidence and consequence of spine fractures in trauma-related combat amputees are unknown. This study sought to determine the incidence and morbidity of the associated spine fractures on patients with traumatic lower extremity amputation sustained during OIF/OEF. Retrospective case control. Two hundred twenty-six combat-related lower extremity amputees presenting to a single institution and injured between 2003 and 2008 were included for analysis. Physiologic and functional outcome measures were used to determine the influence of spine fractures on combat amputees. Physiologic measures included intensive care unit (ICU) admission rates, injury severity score (ISS), rate of narcotic/neuropathic pain use, and heterotopic ossification (HO) rates. Functional outcome measures included return-to-duty rates and ambulatory status at final follow-up. Data from 300 consecutive combat-related lower extremity amputations were retrospectively reviewed and grouped. Group 1 consisted of amputees with associated spine fractures, and Group 2 consisted of amputees without spine fractures. The results of the two groups were compared with regard to initial presentation and final functional outcomes. A total of 226 patients sustained 300 lower extremity amputations secondary to combat-related injuries, the most common mechanism being an improvised explosive device. Twenty-nine of these patients had a spine fracture (13%). Group 1 had a higher ISS than Group 2 (30 vs. 19, p<.001). Group 1 patients were also more likely to be admitted to the ICU (86% vs. 46%, p<.001). Furthermore, Group 1 patients had a significantly higher rate of HO in their residual limbs (82% vs. 55%, p<.005). The incidence of spine fractures in combat-related amputees is 13%. The results suggest that combat-related amputees with spine fractures are more likely to sustain severe injuries to other body systems, as indicated by the significantly higher ISS and rates of ICU admission. This group also had a significantly higher rate of HO formation, which may be attributable to the greater local and/or systemic injuries sustained by these patients. Published by Elsevier Inc.

Understanding adaptive gait in lower-limb amputees: insights from multivariate analyses

PubMed Central

2013-01-01

Background In this paper we use multivariate statistical techniques to gain insights into how adaptive gait involving obstacle crossing is regulated in lower-limb amputees compared to able-bodied controls, with the aim of identifying underlying characteristics that differ between the two groups and consequently highlighting gait deficits in the amputees. Methods Eight unilateral trans-tibial amputees and twelve able-bodied controls completed adaptive gait trials involving negotiating various height obstacles; with amputees leading with their prosthetic limb. Spatiotemporal variables that are regularly used to quantify how gait is adapted when crossing obstacles were determined and subsequently analysed using multivariate statistical techniques. Results and discussion There were fundamental differences in the adaptive gait between the two groups. Compared to controls, amputees had a reduced approach velocity, reduced foot placement distance before and after the obstacle and reduced foot clearance over it, and reduced lead-limb knee flexion during the step following crossing. Logistic regression analysis highlighted the variables that best distinguished between the gait of the two groups and multiple regression analysis (with approach velocity as a controlling factor) helped identify what gait adaptations were driving the differences seen in these variables. Getting closer to the obstacle before crossing it appeared to be a strategy to ensure the heel of the lead-limb foot passed over the obstacle prior to the foot being lowered to the ground. Despite adopting such a heel clearance strategy, the lead-foot was positioned closer to the obstacle following crossing, which was likely a result of a desire to attain a limb/foot angle and orientation at instant of landing that minimised loads on the residuum (as evidenced by the reduced lead-limb knee flexion during the step following crossing). These changes in foot placement meant the foot was in a different part of swing at point of crossing and this explains why foot clearance was considerably reduced in amputees. Conclusions These results highlight that trans-tibial amputees use quite different gait adaptations to cross obstacles compared with controls (at least when leading with their prosthetic limb), indicating they are governed by different constraints; seemingly related to how they land on/load their prosthesis after crossing the obstacle. PMID:23958032

Mechanisms of Gait Asymmetry Due to Push-off Deficiency in Unilateral Amputees

PubMed Central

Adamczyk, Peter Gabriel; Kuo, Arthur D.

2015-01-01

Unilateral lower-limb amputees exhibit asymmetry in many gait features, such as ground force, step time, step length, and joint mechanics. Although these asymmetries result from weak prosthetic-side push-off, there is no proven mechanistic explanation of how that impairment propagates to the rest of the body. We used a simple dynamic walking model to explore possible consequences of a unilateral impairment similar to that of a transtibial amputee. The model compensates for reduced push-off work from one leg by performing more work elsewhere, for example during the middle of stance by either or both legs. The model predicts several gait abnormalities, including slower forward velocity of the body center-of-mass (COM) during intact-side stance, greater energy dissipation in the intact side, and more positive work overall. We tested these predictions with data from unilateral transtibial amputees (N = 11) and non-amputee control subjects (N = 10) walking on an instrumented treadmill. We observed several predicted asymmetries, including forward velocity during stance phases and energy dissipation from the two limbs, as well as greater work overall. Secondary adaptations, such as to reduce discomfort, may exacerbate asymmetry, but these simple principles suggest that some asymmetry may be unavoidable in cases of unilateral limb loss. PMID:25222950

Using virtual reality environment to facilitate training with advanced upper-limb prosthesis.

PubMed

Resnik, Linda; Etter, Katherine; Klinger, Shana Lieberman; Kambe, Charles

2011-01-01

Technological advances in upper-limb prosthetic design offer dramatically increased possibilities for powered movement. The DEKA Arm system allows users 10 powered degrees of movement. Learning to control these movements by utilizing a set of motions that, in most instances, differ from those used to obtain the desired action prior to amputation is a challenge for users. In the Department of Veterans Affairs "Study to Optimize the DEKA Arm," we attempted to facilitate motor learning by using a virtual reality environment (VRE) program. This VRE program allows users to practice controlling an avatar using the controls designed to operate the DEKA Arm in the real world. In this article, we provide highlights from our experiences implementing VRE in training amputees to use the full DEKA Arm. This article discusses the use of VRE in amputee rehabilitation, describes the VRE system used with the DEKA Arm, describes VRE training, provides qualitative data from a case study of a subject, and provides recommendations for future research and implementation of VRE in amputee rehabilitation. Our experience has led us to believe that training with VRE is particularly valuable for upper-limb amputees who must master a large number of controls and for those amputees who need a structured learning environment because of cognitive deficits.

Observation-based training for neuroprosthetic control of grasping by amputees.

PubMed

Agashe, Harshavardhan A; Contreras-Vidal, Jose L

2014-01-01

Current brain-machine interfaces (BMIs) allow upper limb amputees to position robotic arms with a high degree of accuracy, but lack the ability to control hand pre-shaping for grasping different objects. We have previously shown that low frequency (0.1-1 Hz) time domain cortical activity recorded at the scalp via electroencephalography (EEG) encodes information about grasp pre-shaping. To transfer this technology to clinical populations such as amputees, the challenge lies in constructing BMI models in the absence of overt training hand movements. Here we show that it is possible to train BMI models using observed grasping movements performed by a robotic hand attached to amputees' residual limb. Three transradial amputees controlled the grasping motion of an attached robotic hand via their EEG, following the action-observation training phase. Over multiple sessions, subjects successfully grasped the presented object (a bottle or a credit card) in 53±16 % of trials, demonstrating the validity of the BMI models. Importantly, the validation of the BMI model was through closed-loop performance, which demonstrates generalization of the model to unseen data. These results suggest `mirror neuron system' properties captured by delta band EEG that allows neural representation for action observation to be used for action control in an EEG-based BMI system.

Amputee skin condition: occlusion, stratum corneum hydration and free amino acid levels.

PubMed

Visscher, Marty O; Robinson, Marisa; Fugit, Benetta; Rosenberg, Richard J; Hoath, Steven B; Randall Wickett, R

2011-03-01

Patients with a prosthetic limb report negative skin effects, including irritation, rash and chafing, which can lead to infection, discomfort and reduced wear time to significantly impact normal activities. The aims were to examine the epidermal integrity (transepidermal water loss, TEWL), stratum corneum (SC) hydration [moisture accumulation rate (MAT)], friction and biomechanical properties in active below the knee amputees and to determine the effects of an inert sock liner on skin condition. The liner reduced hydration, TEWL and friction and increased elasticity versus the amputee's conventional skin care methods. Residual limb TEWL was increased and MAT was reduced versus the contralateral normal skin. In a second study, we hypothesized that complete occlusion would decrease free amino acids (FAA) and quantified them by high performance liquid chromatography in an adult volar forearm model. Occlusion with a water vapor impermeable wet dressing led to increased TEWL, erythema and dryness and reduced MAT versus normal skin, comparable to the results in the amputees. The FAA levels were significantly reduced for the occluded sites. The results suggest that residual limb occlusion in amputees may block the formation of FAA in the upper SC. Therapies based on replacement of water binding FAAs, may alleviate the consequences of long-term occlusion.

Increasing ankle push-off work with a powered prosthesis does not necessarily reduce metabolic rate for transtibial amputees.

PubMed

Quesada, Roberto E; Caputo, Joshua M; Collins, Steven H

2016-10-03

Amputees using passive ankle-foot prostheses tend to expend more metabolic energy during walking than non-amputees, and reducing this cost has been a central motivation for the development of active ankle-foot prostheses. Increased push-off work at the end of stance has been proposed as a way to reduce metabolic energy use, but the effects of push-off work have not been tested in isolation. In this experiment, participants with unilateral transtibial amputation (N=6) walked on a treadmill at a constant speed while wearing a powered prosthesis emulator. The prosthesis delivered different levels of ankle push-off work across conditions, ranging from the value for passive prostheses to double the value for non-amputee walking, while all other prosthesis mechanics were held constant. Participants completed six acclimation sessions prior to a data collection in which metabolic rate, kinematics, kinetics, muscle activity and user satisfaction were recorded. Metabolic rate was not affected by net prosthesis work rate (p=0.5; R 2 =0.007). Metabolic rate, gait mechanics and muscle activity varied widely across participants, but no participant had lower metabolic rate with higher levels of push-off work. User satisfaction was affected by push-off work (p=0.002), with participants preferring values of ankle push-off slightly higher than in non-amputee walking, possibly indicating other benefits. Restoring or augmenting ankle push-off work is not sufficient to improve energy economy for lower-limb amputees. Additional necessary conditions might include alternate timing or control, individualized tuning, or particular subject characteristics. Copyright © 2016 Elsevier Ltd. All rights reserved.

Crossover study of amputee stair ascent and descent biomechanics using Genium and C-Leg prostheses with comparison to non-amputee control.

PubMed

Lura, Derek J; Wernke, Matthew W; Carey, Stephanie L; Kahle, Jason T; Miro, Rebecca M; Highsmith, M Jason

2017-10-01

This study was a randomized crossover of stair ambulation of Transfemoral Amputees (TFAs) using the Genium and C-Leg prosthetic knees. TFAs typically have difficulty ascending and descending stairs, limiting community mobility. The objective of this study was to determine the relative efficacy of the Genium and C-Leg prostheses for stair ascent and descent, and their absolute efficacy relative to non-amputees. Twenty TFAs, and five non-amputees participated in the study. TFAs were randomized to begin the study with the Genium or C-Leg prosthesis. Informed consent was obtained from all participants prior to data collection and the study was listed on clinicaltrials.gov (#NCT01473662). After fitting, accommodation, and training, participants were asked to demonstrate their preferred gait pattern for stair ascent and descent and a step-over-step pattern if able. TFAs then switched prosthetic legs and repeated fitting, accommodation, training, and testing. An eight camera Vicon optical motion analysis system, and two AMTI force plates were used to track and analyze the participants' gait patterns, knee flexion angles, knee moment normalized by body weight, and swing time. For stair descent, no significant differences were found between prostheses. For stair ascent, Genium use resulted in: increased ability to use a step-over-step gait pattern (p=0.03), increased prosthetic side peak knee flexion (p<0.01), and increased swing duration (p<0.01). Changes in contralateral side outcomes and in knee moment were not significant. Overall the Genium knee decreased deficiency in gait patterns for stair ascent relative to the C-Leg, by enabling gait patterns that more closely resembled non-amputees. Copyright © 2017 Elsevier B.V. All rights reserved.

Scapular resting position, shoulder pain and function in disabled athletes.

PubMed

Aytar, Aydan; Zeybek, Aslican; Pekyavas, Nihan Ozunlu; Tigli, Ayca Aytar; Ergun, Nevin

2015-10-01

Despite the fact that the number of disabled individuals participating in sports is increasing, there are only sparse reports in the literature concerning overuse injuries. The purpose of this study was to compare scapular resting position, shoulder pain, and function in wheelchair basketball, amputee soccer, and disabled table tennis players. Descriptive study. A total of 63 disabled players from amputee soccer, wheelchair basketball, and disabled table tennis participated in our study. Scapular resting position was taken as primary outcome; pain and function were taken as secondary outcome measurements. Scapular resting position was evaluated with Lateral Scapular Slide Test. Visual Analog Scale was used for evaluating shoulder pain intensity. Quick disabilities of the arm, shoulder, and hand questionnaire were used to assess upper extremity function. There was a significant difference in shoulder pain, function, and scapular resting position in all groups (p < 0.05). Paired comparisons between amputee soccer and wheelchair basketball players and also amputee soccer and disabled table tennis showed difference for all measurement parameters (p < 0.05). When the results are evaluated, it may be stated that amputee soccer players have better scapular resting position than other sports. Crutch usage may not negatively affect scapular resting position and perceived function as much as wheelchair usage. Exercise techniques for shoulder and resting position could be included in training programs of disabled athletes. Wheelchair/crutch usage is a risk, and special exercise techniques for shoulder and dyskinesis could be included in training programs to prevent injury. However, it may not just be important for wheelchair athletes, it may also be important for amputee soccer players. In particular, total upper extremity evaluations and exercises could be added within exercise programs. © The International Society for Prosthetics and Orthotics 2014.

Designing for scale: development of the ReMotion Knee for global emerging markets.

PubMed

Hamner, Samuel R; Narayan, Vinesh G; Donaldson, Krista M

2013-09-01

Amputees living in developing countries have a profound need for affordable and reliable lower limb prosthetic devices. The World Health Organization estimates there are approximately 30 million amputees living in low-income countries, with up to 95% lacking access to prosthetic devices. Effective prosthetics can significantly affect the lives of these amputees by increasing opportunity for employment and providing improvements to long-term health and well-being. However, current solutions are inadequate: state-of-the-art solutions from the US and Europe are cost-prohibitive, while low-cost devices have been challenged by poor quality and/or unreliable performance, and have yet to achieve large scale impact. The introduction of new devices is hampered by the lack of a cohesive prosthetics industry in low-income areas; the current network of low-cost prosthetic clinics is informal and loosely organized with significant disparities in geography, patient volume and demographics, device procurement, clinical and logistical infrastructure, and funding. At D-Rev (Design Revolution) we are creating the ReMotion Knee, which is an affordable polycentric prosthetic knee joint that performs on par with devices in more industrialized regions, like the US and Europe. As of September 2012, over 4200 amputees have been fitted with the initial version of the ReMotion Knee through a partnership with the JaipurFoot Organization, with an 79% compliance rate after 2 years. We are currently scaling production of the ReMotion Knee using centralized manufacturing and distribution to serve the existing clinics in low-income countries and increase the availability of devices for amputees without access to appropriate care. At D-Rev, we develop products that target these customers through economically-sustainable models and provide a measurable impact in the lives of the world's amputees.

Amputations in the burn unit: A retrospective analysis of 82 patients across 12 years.

PubMed

Li, Quan; Wang, Ling-Feng; Chen, Qiang; Wang, Shu-Jie; Li, Fang; Ba, Te

2017-11-01

The aim of this study is to analyze the data of amputees in the burn center of the Inner Mongolia region and to provide instructive suggestions for a preventative reduction of the amputation rate. Between 2004 and 2016, all patient medical profiles were reviewed to extract data of patients with major amputation. Demographic data, mechanism of injury, location and level of amputation were recorded. The healing condition of the residual limb was noted. In addition, we performed comparisons of amputees whose injuries were caused by electricity and those whose injuries were related to other mechanisms. Among the 82 amputees in our study, about 89% of amputees were male patients and the predominant age-group was 20-29 years (26.8%). The injuries occurred most commonly at the work place (62.2%) with laborers (40.2%) being the most commonly affected. The most common mechanisms of injury were electricity (51.2%) and hot crush (14.6%), followed by frostbite (13.4%). The most common level of amputation was the right wrist joint (n=16). About 60.4% of the amputation sites were by primary healing. The rate of escharotomy in electrical burn amputees (n=27, 62.3%) was significantly higher than the other groups (n=16, 40.0%, p<0.05). The first amputation in electrical burn group (7.2±5.6) was significantly earlier than the other etiology group (17.9±13.7, p<0.05). Electrical burns were the major mechanism of injury among amputees. Effective safety measures, factory modifications, and adequate instructions should be implemented to protect laborers. Urgent interdisciplinary communication should be taken into account for the prevention reduction of the amputation rate in our region. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

Improved Training Method for Rapid Rehabilitation of Amputees

DTIC Science & Technology

2013-03-01

crowded environments, stairs , ramps, and hills. The key factor that limits the ability of amputees to achieve maximum functional capabilities is falls...Method for evoking a trip response using a treadmill based perturbation during locomotion”, has been submitted to the Journal of Biomechanics o

Gait asymmetry of transfemoral amputees using mechanical and microprocessor-controlled prosthetic knees.

PubMed

Kaufman, Kenton R; Frittoli, Serena; Frigo, Carlo A

2012-06-01

Amputees walk with an asymmetrical gait, which may lead to future musculoskeletal degenerative changes. The purpose of this study was to compare the gait asymmetry of active transfemoral amputees while using a passive mechanical knee joint or a microprocessor-controlled knee joint. Objective 3D gait measurements were obtained in 15 subjects (12 men and 3 women; age 42, range 26-57). Research participants were longtime users of a mechanical prosthesis (mean 20 years, range 3-36 years). Joint symmetry was calculated using a novel method that includes the entire waveform throughout the gait cycle. There was no significant difference in hip, knee and ankle kinematics symmetry when using the different knee prostheses. In contrast, the results demonstrated a significant improvement in lower extremity joint kinetics symmetry when using the microprocessor-controlled knee. Use of the microprocessor-controlled knee joint resulted in improved gait symmetry. These improvements may lead to a reduction in the degenerative musculoskeletal changes often experienced by amputees. Copyright © 2011 Elsevier Ltd. All rights reserved.

Prosthetic helping hand

NASA Technical Reports Server (NTRS)

Vest, Thomas W. (Inventor); Carden, James R. (Inventor); Norton, William E. (Inventor); Belcher, Jewell G. (Inventor)

1992-01-01

A prosthetic device for below-the-elbow amputees, having a C-shaped clamping mechanism for grasping cylindrical objects, is described. The clamping mechanism is pivotally mounted to a cuff that fits on the amputee's lower arm. The present invention is utilized by placing an arm that has been amputated below the elbow into the cuff. The clamping mechanism then serves as a hand whenever it becomes necessary for the amputee to grasp a cylindrical object such as a handle, a bar, a rod, etc. To grasp the cylindrical object, the object is jammed against the opening in the C-shaped spring, causing the spring to open, the object to pass to the center of the spring, and the spring to snap shut behind the object. Various sizes of clamping mechanisms can be provided and easily interchanged to accommodate a variety of diameters. With the extension that pivots and rotates, the clamping mechanism can be used in a variety of orientations. Thus, this invention provides the amputee with a clamping mechanism that can be used to perform a number of tasks.

Ultrasonographic assessment of the quadriceps muscle and femoral cartilage in transtibial amputees using different prostheses.

PubMed

Şahin Onat, Şule; Malas, Fevziye Ünsal; Öztürk, Gökhan Tuna; Akkaya, Nuray; Kara, Murat; Özçakar, Levent

2016-08-01

In patients with lower limb amputations, gait alteration, increased loading on the intact extremity, and use of prosthesis may lead to joint degeneration. To explore the effects of prosthesis type on quadriceps muscle and distal femoral cartilage thicknesses in transtibial amputees. A cross-sectional study. A total of 38 below-knee amputees were enrolled in the study, of which 13 patients were using vacuum system type prosthesis and 25 patients were using silicon liner pin system prosthesis. Patients' femoral cartilage and quadriceps muscle thickness measurements were performed using musculoskeletal ultrasound. When compared with the intact sides, cartilage and rectus femoris, vastus intermedius, and vastus medialis muscle thickness values were significantly decreased on the amputee sides (all p < 0.05). Clinical characteristics and ultrasound measurements were similar between the two groups except the lateral and medial femoral condyle thicknesses, thinner in the silicon liner pin system users (both p < 0.05). The distal femoral cartilage and quadriceps muscle thicknesses were found to be decreased on the amputated sides, and the negative impact on the cartilage seemed to be worse in the silicon liner pin system users. This study might provide another argument as regards the preference of vacuum system type prosthesis to prevent possible knee osteoarthritis due to cartilage thinning in adult transtibial amputees. © The International Society for Prosthetics and Orthotics 2015.

Perspiration Thresholds and Secure Suspension for Lower Limb Amputees in Demanding Environments

DTIC Science & Technology

2015-10-01

VAPSHCS) site, fabricating custom, moisture-wicking textile sock with a proximal elastomeric seal, fabricating prosthetic sockets, fabricating electronic...Aims: This research has two specific aims: (1) determine if lower limb amputees are willing to use smart activity monitors as part of their daily life

Sports Adaptations for Unilateral and Bilateral Upper-Limb Amputees: Archery/Badminton/Baseball/Softball/Bowling/Golf/Table Tennis.

ERIC Educational Resources Information Center

Cowart, Jim

1979-01-01

The booklet discusses sports adaptations for unilateral and bilateral upper limb amputees. Designs for adapted equipment are illustrated and information on adaptations are described for archery (including an archery release aid and a stationary bow holder); badminton (serving tray); baseball/softball (adaptations for catching, throwing, and…

Optical fiber Bragg grating-instrumented silicone liner for interface pressure measurement within prosthetic sockets of lower-limb amputees

NASA Astrophysics Data System (ADS)

Al-Fakih, Ebrahim; Arifin, Nooranida; Pirouzi, Gholamhossein; Mahamd Adikan, Faisal Rafiq; Shasmin, Hanie Nadia; Abu Osman, Noor Azuan

2017-08-01

This paper presents a fiber Bragg grating (FBG)-instrumented prosthetic silicone liner that provides cushioning for the residual limb and can successfully measure interface pressures inside prosthetic sockets of lower-limb amputees in a simple and practical means of sensing. The liner is made of two silicone layers between which 12 FBG sensors were embedded at locations of clinical interest. The sensors were then calibrated using a custom calibration platform that mimics a real-life situation. Afterward, a custom gait simulating machine was built to test the liner performance during an amputee's simulated gait. To validate the findings, the results were compared to those obtained by the commonly used F-socket mats. As the statistical findings reveal, both pressure mapping methods measured the interface pressure in a consistent way, with no significant difference (P-values ≥0.05). This pressure mapping technique in the form of a prosthetic liner will allow prosthetics professionals to quickly and accurately create an overall picture of the interface pressure distribution inside sockets in research and clinical settings, thereby improving the socket fit and amputee's satisfaction.

Nutritional profile of the Brazilian Amputee Soccer Team during the precompetition period for the world championship.

PubMed

Innocencio da Silva Gomes, Ainá; Gonçalves Ribeiro, Beatriz; de Abreu Soares, Eliane

2006-10-01

The purpose of this study was to determine the dietary and anthropometric profiles of the Brazilian amputee soccer players during the training period before the world soccer amputee championship, according to their positional roles in the game. Fifteen male athletes participated in the study. Data on height, weight, skinfold thickness, and circumferences were collected to assess nutritional status. Dietary intake was obtained by using 6-d dietary records, analyzed by a Nutrition Support Program for total energy intake, carbohydrates, proteins, lipids, vitamins, and minerals. One-way analysis of variance was used to identify differences in groups (P < 0.05). Midfield players were heavier than the others, and this difference may have been caused by a large quantity of subcutaneous fat. Dietary data showed a low carbohydrate intake and high protein and fat intakes. No athlete met the recommendations for vitamin E, and forward players did not meet recommendations for calcium. Amputee athletes need an individualized nutritional orientation and the lack of information about disabled sports and athletes highlights the need for more studies in this area.

Heterotopic ossification in civilians with lower limb amputations.

PubMed

Matsumoto, Mary E; Khan, Mohammed; Jayabalan, Prakash; Ziebarth, Jessica; Munin, Michael C

2014-09-01

To report the incidence of symptomatic heterotopic ossification (HO) in a defined civilian amputee population, describe its characteristics, and compare these findings to published data in military amputees. Retrospective chart analysis from July 1998 to July 2009. Ambulatory amputee clinic within a large university medical center. Adults with lower limb amputation (N=158). Not applicable. Patients with symptomatic HO confirmed by radiographs. A total of 261 patients were evaluated; 158 met inclusion criteria, with 59% having traumatic etiology, 18% vascular etiology, 22% infection, and 1% tumor. Symptomatic HO was diagnosed in 36 (22.8%) patients, and 94% patients had mild HO on radiographic scoring. Rate of HO in amputations related to trauma was not increased compared with those of other etiologies. Surgical resection of the ectopic bone was required in 4 (11%) patients. HO is seen commonly after civilian lower limb amputation regardless of etiology. The prevalence was less than that observed in previous reports from military populations. This is the first report estimating the prevalence of HO in adult civilian amputees. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Individual responses to alignment perturbations in socket reaction moments while walking in transtibial prostheses.

PubMed

Kobayashi, Toshiki; Orendurff, Michael S; Zhang, Ming; Boone, David A

2014-05-01

The alignment of transtibial prostheses has a systematic effect on the mean socket reaction moments in amputees. However, understanding their individual differences in response to alignment perturbations is also important for prosthetists to fully utilize the socket reaction moments for dynamic alignment in each unique patient. The aim of this study was to investigate individual responses to alignment perturbations in transtibial prostheses with solid-ankle-cushion-heel feet. A custom instrumented prosthesis alignment component was used to measure the socket reaction moments while walking in 11 amputees with transtibial prostheses under 17 alignment conditions, including 3° and 6° of flexion, extension, abduction, and adduction of the socket, 5mm and 10mm of anterior, posterior, lateral, and medial translation of the socket, and an initial baseline alignment. Coronal moments at 30% of stance and maximum sagittal moments were extracted for comparisons from each amputee. In the coronal plane, varus moment at 30% of stance was generally reduced by adduction or medial translation of the socket in all the amputees. In the sagittal plane, extension moment was generally increased by posterior translation or flexion of the socket; however, this was not necessarily the case for all the amputees. Individual responses to alignment perturbations are not always consistent, and prosthetists would need to be aware of this variance when addressing individual socket reaction moments during dynamic alignment in clinical setting. Copyright © 2014 Elsevier Ltd. All rights reserved.

Exploring ethical justification for self-demand amputation.

PubMed

Tomasini, Floris

2006-01-01

Self-demand amputees are persons who need to have one or more healthy limbs or digits amputated to fit the way they see themselves. They want to rid themselves of a limb that they believe does not belong to their body-identity. The obsessive desire to have appendages surgically removed to fit an alternative body-image is medically and ethically controversial. My purpose in this paper is to provide a number of normative and professional ethical perspectives on whether or not it is possible to justify surgery for self-demand amputees. In doing so I proceed dialogically, moving between empirical context and normative theory, revealing the taken for granted normative assumptions (what I call the natural attitude--a technical term borrowed from phenomenology) that provide ethical limits to justifying the treatment of self-demand amputees. While I critically examine both Kantian responses against as well as Utilitarian responses for amputation on demand, I conclude that neither normative tradition can fully incorporate an understanding of what it is like to be a self-demand amputee. Since neither theory can justify the apparent non-rational desire of amputation on demand, ethical justification, I argue, falls short of the recognition that there may be a problem. To end, I introduce a meta-ethical idea, "the struggle for recognition," opening up the theoretical possibility of a hermeneutics of recognition before ethical justification that may be more sensitive to the problem of radical embodied difference exemplified by self-demand amputees.

Kinetic and Kinematic Differences in a Golf Swing in One and Both Lower Limb Amputees

PubMed Central

Stastny, Petr; Maszczyk, Adam; Tománková, Kristina; Kubový, Petr; Richtrová, Michaela; Otáhal, Jakub; Čichoň, Rostislav; Mostowik, Aleksandra; Żmijewski, Piotr; Cięszczyk, Paweł

2015-01-01

Amputee golfers need to cope with the absence of sole proprioception, a decreased range of swing motion and other factors which should be recognized for training purposes. The aim of this study was to determine the kinetic and kinematic differences in the golf swing in one leg and two legs amputees. The participants consisted of two males and one female at a professional or amateur level with a different degree of disability. Each participant was taped by 3D markers and performed five golf swings with the iron 6. The intraclass correlation coefficient (ICC) did not vary between individuals in kinematics, however, it was low in kinetic variables of two leg amputees. The Kendal rank correlation showed a significant relationship between the level of amputation and a large number of kinetic and kinematic variables such as X factor, O factor, S factor and individual body angles. The fluency and similarity of the golf swing did not depend on the level of amputation. One lower limb amputation did not seem to increase movement variability contrary to two lower limb amputation. The most variable parameter was a weight-shift in all golfers. The takeaway and horizontal force angle depended on the level of amputation rather than individual technique, thus, their modification by training may be difficult. Estimation of golf swing „mistakes” in amputees in respect to the leading arm in an early follow or late follow position appeared to be useless. PMID:26834871

Kinetic and Kinematic Differences in a Golf Swing in One and Both Lower Limb Amputees.

PubMed

Stastny, Petr; Maszczyk, Adam; Tománková, Kristina; Kubový, Petr; Richtrová, Michaela; Otáhal, Jakub; Čichoň, Rostislav; Mostowik, Aleksandra; Żmijewski, Piotr; Cięszczyk, Paweł

2015-11-22

Amputee golfers need to cope with the absence of sole proprioception, a decreased range of swing motion and other factors which should be recognized for training purposes. The aim of this study was to determine the kinetic and kinematic differences in the golf swing in one leg and two legs amputees. The participants consisted of two males and one female at a professional or amateur level with a different degree of disability. Each participant was taped by 3D markers and performed five golf swings with the iron 6. The intraclass correlation coefficient (ICC) did not vary between individuals in kinematics, however, it was low in kinetic variables of two leg amputees. The Kendal rank correlation showed a significant relationship between the level of amputation and a large number of kinetic and kinematic variables such as X factor, O factor, S factor and individual body angles. The fluency and similarity of the golf swing did not depend on the level of amputation. One lower limb amputation did not seem to increase movement variability contrary to two lower limb amputation. The most variable parameter was a weight-shift in all golfers. The takeaway and horizontal force angle depended on the level of amputation rather than individual technique, thus, their modification by training may be difficult. Estimation of golf swing "mistakes" in amputees in respect to the leading arm in an early follow or late follow position appeared to be useless.

Effects of Lumbar Strengthening Exercise in Lower-Limb Amputees With Chronic Low Back Pain.

PubMed

Shin, Min Kyung; Yang, Hee Seung; Yang, Hea-Eun; Kim, Dae Hyun; Ahn, Bo Ram; Kwon, Hyup; Lee, Ju Hwan; Jung, Suk; Choi, Hyun Chul; Yun, Sun Keaung; Ahn, Dong Young; Sim, Woo Sob

2018-02-01

To analyze the effect of lumbar strengthening exercise in lower-limb amputees with chronic low back pain. We included in this prospective study 19 lower-limb amputees who had experienced low back pain for longer than 6 months. Participants were treated with 30-minute lumbar strengthening exercises, twice weekly, for 8 weeks. We used the visual analog scale (VAS), and Oswestry low back pain disability questionnaire, and measured parameters such as iliopsoas length, abdominal muscle strength, back extensor strength, and back extensor endurance. In addition, we assessed the isometric peak torque and total work of the trunk flexors and extensors using isokinetic dynamometer. The pre- and post-exercise measurements were compared. Compared with the baseline, abdominal muscle strength (from 4.4±0.7 to 4.8±0.6), back extensor strength (from 2.6±0.6 to 3.5±1.2), and back extensor endurance (from 22.3±10.7 to 46.8±35.1) improved significantly after 8 weeks. The VAS decreased significantly from 4.6±2.2 to 2.6±1.6 after treatment. Furthermore, the peak torque and total work of the trunk flexors and extensors increased significantly (p<0.05). Lumbar strengthening exercise in lower-limb amputees with chronic low back pain resulted in decreased pain and increased lumbar extensor strength. The lumbar strengthening exercise program is very effective for lower-limb amputees with chronic low back pain.

Apparent motion perception in lower limb amputees with phantom sensations: "obstacle shunning" and "obstacle tolerance".

PubMed

Saetta, Gianluca; Grond, Ilva; Brugger, Peter; Lenggenhager, Bigna; Tsay, Anthony J; Giummarra, Melita J

2018-03-21

Phantom limbs are the phenomenal persistence of postural and sensorimotor features of an amputated limb. Although immaterial, their characteristics can be modulated by the presence of physical matter. For instance, the phantom may disappear when its phenomenal space is invaded by objects ("obstacle shunning"). Alternatively, "obstacle tolerance" occurs when the phantom is not limited by the law of impenetrability and co-exists with physical objects. Here we examined the link between this under-investigated aspect of phantom limbs and apparent motion perception. The illusion of apparent motion of human limbs involves the perception that a limb moves through or around an object, depending on the stimulus onset asynchrony (SOA) for the two images. Participants included 12 unilateral lower limb amputees matched for obstacle shunning (n = 6) and obstacle tolerance (n = 6) experiences, and 14 non-amputees. Using multilevel linear models, we replicated robust biases for short perceived trajectories for short SOA (moving through the object), and long trajectories (circumventing the object) for long SOAs in both groups. Importantly, however, amputees with obstacle shunning perceived leg stimuli to predominantly move through the object, whereas amputees with obstacle tolerance perceived leg stimuli to predominantly move around the object. That is, in people who experience obstacle shunning, apparent motion perception of lower limbs was not constrained to the laws of impenetrability (as the phantom disappears when invaded by objects), and legs can therefore move through physical objects. Amputees who experience obstacle tolerance, however, had stronger solidity constraints for lower limb apparent motion, perhaps because they must avoid co-location of the phantom with physical objects. Phantom limb experience does, therefore, appear to be modulated by intuitive physics, but not in the same way for everyone. This may have important implications for limb experience post-amputation (e.g., improving prosthesis embodiment when limb representation is constrained by the same limits as an intact limb). Copyright © 2018 Elsevier Ltd. All rights reserved.

The Effect of a Microprocessor Prosthetic Foot on Function and Quality of Life in Transtibial Amputees Who Are Limited Community Ambulators

DTIC Science & Technology

with greater range of motion and active power, will translate into improved functional performance, ambulatory safety (risk of falls) and quality of... life in trans-tibial amputees (TTA) who function as limited community ambulators. We will assess these outcomes in 54 veterans with TTA by randomizing

From research to self-reflection: learning about ourselves as academics through a support group's resistance to our intervention.

PubMed

Scherr, Courtney Lynam; Mattson, Marifran

2012-01-01

Purdue University's Center for Healthcare Engineering developed a computer-assisted technology hub (CATHUB) designed to aid individuals with disabilities. Upon realizing the lack of input from the very individuals they were trying to help, Marifran approached the developers of CATHUB and offered to engage a group of amputees to aid in the design and implementation of the hub. In this essay, Courtney and Marifran recount, each from their own perspective, their experiences working with Amputees in Action as participants in their research project. Ultimately the researchers discovered their research agenda was not compatible with the amputees' needs, resulting in enlightened self-reflection by the researchers and abandonment of the research project.

Functional expansion of sensorimotor representation and structural reorganization of callosal connections in lower limb amputees.

PubMed

Simões, Elington L; Bramati, Ivanei; Rodrigues, Erika; Franzoi, Ana; Moll, Jorge; Lent, Roberto; Tovar-Moll, Fernanda

2012-02-29

Previous studies have indicated that amputation or deafferentation of a limb induces functional changes in sensory (S1) and motor (M1) cortices, related to phantom limb pain. However, the extent of cortical reorganization after lower limb amputation in patients with nonpainful phantom phenomena remains uncertain. In this study, we combined functional magnetic resonance (fMRI) and diffusion tensor imaging (DTI) to investigate the existence and extent of cortical and callosal plasticity in these subjects. Nine "painless" patients with lower limb amputation and nine control subjects (sex- and age-matched) underwent a 3-T MRI protocol, including fMRI with somatosensory stimulation. In amputees, we observed an expansion of activation maps of the stump in S1 and M1 of the deafferented hemisphere, spreading to neighboring regions that represent the trunk and upper limbs. We also observed that tactile stimulation of the intact foot in amputees induced a greater activation of ipsilateral S1, when compared with controls. These results demonstrate a functional remapping of S1 in lower limb amputees. However, in contrast to previous studies, these neuroplastic changes do not appear to be dependent on phantom pain but do also occur in those who reported only the presence of phantom sensation without pain. In addition, our findings indicate that amputation of a limb also induces changes in the cortical representation of the intact limb. Finally, DTI analysis showed structural changes in the corpus callosum of amputees, compatible with the hypothesis that phantom sensations may depend on inhibitory release in the sensorimotor cortex.

Toward Balance Recovery With Leg Prostheses Using Neuromuscular Model Control

PubMed Central

Geyer, Hartmut

2016-01-01

Objective Lower limb amputees are at high risk of falling as current prosthetic legs provide only limited functionality for recovering balance after unexpected disturbances. For instance, the most established control method used on powered leg prostheses tracks local joint impedance functions without taking the global function of the leg in balance recovery into account. Here we explore an alternative control policy for powered transfemoral prostheses that considers the global leg function and is based on a neuromuscular model of human locomotion. Methods We adapt this model to describe and simulate an amputee walking with a powered prosthesis using the proposed control, and evaluate the gait robustness when confronted with rough ground and swing leg disturbances. We then implement and partially evaluate the resulting controller on a leg prosthesis prototype worn by a non-amputee user. Results In simulation, the proposed prosthesis control leads to gaits that are more robust than those obtained by the impedance control method. The initial hardware experiments with the prosthesis prototype show that the proposed control reproduces normal walking patterns qualitatively and effectively responds to disturbances in early and late swing. However, the response to mid-swing disturbances neither replicates human responses nor averts falls. Conclusions The neuromuscular model control is a promising alternative to existing prosthesis controls, although further research will need to improve on the initial implementation and determine how well these results transfer to amputee gait. Significance This work provides a potential avenue for future development of control policies that help improve amputee balance recovery. PMID:26315935

Innovative Use of Thighplasty to Improve Prosthesis Fit and Function in a Transfemoral Amputee.

PubMed

Kuiken, Todd A; Fey, Nicholas P; Reissman, Timothy; Finucane, Suzanne B; Dumanian, Gregory A

2018-01-01

Excess residual limb fat is a common problem that can impair prosthesis control and negatively impact gait. In the general population, thighplasty and liposuction are commonly performed for cosmetic reasons but not specifically to improve function in amputees. The objective of this study was to determine if these procedures could enhance prosthesis fit and function in an overweight above-knee amputee. We evaluated the use of these techniques on a 50-year-old transfemoral amputee who was overweight. The patient underwent presurgical imaging and tests to measure her residual limb tissue distribution, socket-limb interface stiffness, residual femur orientation, lower-extremity function, and prosthesis satisfaction. A medial thighplasty procedure with circumferential liposuction was performed, during which 2,812 g (6.2 lbs.) of subcutaneous fat and skin was removed from her residual limb. Imaging was repeated 5 months postsurgery; functional assessments were repeated 9 months postsurgery. The patient demonstrated notable improvements in socket fit and in performing most functional and walking tests. Her comfortable walking speed increased 13.3%, and her scores for the Sit-to-Stand and Four Square Step tests improved over 20%. Femur alignment in her socket changed from 8.13 to 4.14 degrees, and analysis showed a marked increase in the socket-limb interface stiffness. This study demonstrates the potential of using a routine plastic surgery procedure to modify the intrinsic properties of the limb and to improve functional outcomes in overweight or obese transfemoral amputees. This technique is a potentially attractive option compared with multiple reiterations of sockets, which can be time-consuming and costly.

Kinematic differences exist between transtibial amputee fallers and non-fallers during downwards step transitioning.

PubMed

Vanicek, Natalie; Strike, Siobhán C; Polman, Remco

2015-08-01

Stair negotiation is biomechanically more challenging than level gait. There are few biomechanical assessments of transtibial amputees descending stairs and none specifically related to falls. Stair descent may elicit more differences than level gait in amputees with and without a previous falls history. The aim of this study was to compare the gait kinematics of fallers and non-fallers during downwards step transitioning in transtibial amputees. Cross-sectional study. Six fallers and five non-fallers completed step transition trials on a three-step staircase at their self-selected pace. Nine participants exhibited a clear preference to lead with the affected limb, while two had no preference. Four participants self-selected a step-to rather than a reciprocal stair descent strategy. The fallers who used a reciprocal strategy walked 44% more quickly than the non-fallers. To compensate for the lack of active plantar flexion of the prosthetic foot, exaggerated range of motion occurred proximally at the pelvis during swing. The step-to group was more reliant on the handrails than the reciprocal group and walked more slowly. As anticipated, the fallers walked faster than the non-fallers despite employing the more difficult 'roll-over' technique. Handrail use could help to improve dynamic control during downwards step transitions. Transtibial amputees are advised to descend steps using external support, such as handrails, for enhanced dynamic control. Hip abductor and knee extensor eccentric strength should be improved through targeted exercise. Prosthetic socket fit should be checked to allow adequate knee range of motion on the affected side. © The International Society for Prosthetics and Orthotics 2014.

Role of development in reorganization of the SI forelimb-stump representation in fetally, neonatally, and adult amputated rats.

PubMed

Pluto, Charles P; Lane, Richard D; Chiaia, Nicolas L; Stojic, Andrey S; Rhoades, Robert W

2003-09-01

Rats that sustain forelimb removal on postnatal day (P) 0 exhibit numerous multi-unit recording sites in the forelimb-stump representation of primary somatosensory cortex (SI) that also respond to hindlimb stimulation when cortical GABAA+B receptors are blocked. Most of these hindlimb inputs originate in the medial SI hindlimb representation. Although many forelimb-stump sites in these animals respond to hindlimb stimulation, very few respond to stimulation of the face (vibrissae or lower jaw), which is represented in SI just lateral to the forelimb. The lateral to medial development of SI may influence the capacity of hindlimb (but not face) inputs to "invade" the forelimb-stump region in neonatal amputees. The SI forelimb-stump was mapped in adult (>60 days) rats that had sustained amputation on embryonic day (E) 16, on P0, or during adulthood. GABA receptors were blocked and subsequent mapping revealed increases in nonstump inputs in E16 and P0 amputees: fetal amputees exhibited forelimb-stump sites responsive to face (34%), hindlimb (10%), and both (22%); neonatal amputees exhibited 10% face, 39% hindlimb, and 5% both; adult amputees exhibited 10% face, 5% hindlimb, and 0% both, with approximately 80% stump-only sites. These results indicate age-dependent differences in receptive-field reorganization of the forelimb-stump representation, which may reflect the spatiotemporal development of SI. Results from cobalt chloride inactivation of the SI vibrissae region and electrolesioning of the dysgranular cortex suggest that normally suppressed vibrissae inputs to the SI forelimb-stump area originate in the SI vibrissae region and synapse in the dysgranular cortex.

Transtibial prosthesis suspension systems: systematic review of literature.

PubMed

Gholizadeh, H; Abu Osman, N A; Eshraghi, A; Ali, S; Razak, N A

2014-01-01

Today a number of prosthetic suspension systems are available for transtibial amputees. Consideration of an appropriate suspension system can ensure that amputee's functional needs are satisfied. The higher the insight to suspension systems, the easier would be the selection for prosthetists. This review attempted to find scientific evidence pertaining to various transtibial suspension systems to provide selection criteria for clinicians. Databases of PubMed, Web of Science, and ScienceDirect were explored to find related articles. Search terms were as follows: "Transtibial prosthesis (32), prosthetic suspension (48), lower limb prosthesis (54), below-knee prosthesis (58), prosthetic liner (20), transtibial (193), and prosthetic socket (111)". Two reviewers separately examined the papers. Study design (case series of five or more subjects, retrospective or prospective), research instrument, sampling method, outcome measures and protocols were reviewed. Based on the selection criteria, 22 articles (15 prospective studies, and 7 surveys) remained. Sweat control was found to be a major concern with the available suspension liners. Donning and doffing procedures for soft liners are also problematic for some users, particularly those with upper limb weakness. Moreover, the total surface bearing (TSB) socket with pin/lock system is favored by the majority of amputees. In summary, no clinical evidence is available to suggest what kind of suspension system could have an influential effect as a "standard" system for all transtibial amputees. However, among various suspension systems for transtibial amputees, the Iceross system was favored by the majority of users in terms of function and comfort. © 2013. Published by Elsevier Ltd. All rights reserved.

Variables Affecting the Amputees' Reactions Artificial Limbs in the Kingdom of Jordan

ERIC Educational Resources Information Center

Al-Adwan, Mezyed; Najjar, Yahya; Hdaib, Maha; Al-Khateeb, Monadel

2017-01-01

Amputee reaction to artificial limb is an important issue faces amputated individuals and the team who delivers services to these individuals. Although some individuals using artificial limb accept it, some others do not. There are several factors that may make it difficult to accept the artificial limb for a long time. The aim of this study is to…

Development of Subischial Prosthetic Sockets with Vacuum-Assisted Suspension for Highly Active Persons with Transfemoral Amputations

DTIC Science & Technology

2015-10-01

2011;92:1570– 1575 . 12. Ferraro C. Outcomes study of transtibial amputees using elevated vacuum suspension in comparison with pin suspension. J Prosthet...Amputees: Effect on Fit, Activity, and Limb Volume,” Arch. Phys. Med. Rehabil., 92(10), pp. 1570– 1575 . [6] Hoskins, R. D., Sutton, E. E., Kinor, D

Optical fiber Bragg grating-instrumented silicone liner for interface pressure measurement within prosthetic sockets of lower-limb amputees.

PubMed

Al-Fakih, Ebrahim; Arifin, Nooranida; Pirouzi, Gholamhossein; Mahamd Adikan, Faisal Rafiq; Shasmin, Hanie Nadia; Abu Osman, Noor Azuan

2017-08-01

This paper presents a fiber Bragg grating (FBG)-instrumented prosthetic silicone liner that provides cushioning for the residual limb and can successfully measure interface pressures inside prosthetic sockets of lower-limb amputees in a simple and practical means of sensing. The liner is made of two silicone layers between which 12 FBG sensors were embedded at locations of clinical interest. The sensors were then calibrated using a custom calibration platform that mimics a real-life situation. Afterward, a custom gait simulating machine was built to test the liner performance during an amputee's simulated gait. To validate the findings, the results were compared to those obtained by the commonly used F-socket mats. As the statistical findings reveal, both pressure mapping methods measured the interface pressure in a consistent way, with no significant difference (P-values ≥0.05). This pressure mapping technique in the form of a prosthetic liner will allow prosthetics professionals to quickly and accurately create an overall picture of the interface pressure distribution inside sockets in research and clinical settings, thereby improving the socket fit and amputee's satisfaction. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

Stair ascent with an innovative microprocessor-controlled exoprosthetic knee joint.

PubMed

Bellmann, Malte; Schmalz, Thomas; Ludwigs, Eva; Blumentritt, Siegmar

2012-12-01

Climbing stairs can pose a major challenge for above-knee amputees as a result of compromised motor performance and limitations to prosthetic design. A new, innovative microprocessor-controlled prosthetic knee joint, the Genium, incorporates a function that allows an above-knee amputee to climb stairs step over step. To execute this function, a number of different sensors and complex switching algorithms were integrated into the prosthetic knee joint. The function is intuitive for the user. A biomechanical study was conducted to assess objective gait measurements and calculate joint kinematics and kinetics as subjects ascended stairs. Results demonstrated that climbing stairs step over step is more biomechanically efficient for an amputee using the Genium prosthetic knee than the previously possible conventional method where the extended prosthesis is trailed as the amputee executes one or two steps at a time. There is a natural amount of stress on the residual musculoskeletal system, and it has been shown that the healthy contralateral side supports the movements of the amputated side. The mechanical power that the healthy contralateral knee joint needs to generate during the extension phase is also reduced. Similarly, there is near normal loading of the hip joint on the amputated side.

Physical activity and quality of life of amputees in southern Brazil.

PubMed

da Silva, Rudney; Rizzo, Julia Ghazel; Gutierres Filho, Paulo José Barbosa; Ramos, Valmor; Deans, Sarah

2011-12-01

Physical activity is a positive component of human health. Its effects are associated with improvement in physical, psychological and social aspects of quality of life. Physical activity is therefore an important factor in the rehabilitation of amputees. To analyse the relationship between physical activity and quality of life for amputees in southern Brazil. Descriptive, cross-sectional design with nonrandomized sample. A total of 40 questionnaire instruments were distributed to subjects who met the inclusion criteria, with a response rate of 55% (22 individuals, n = 15 males, n = 7 females). Outcome measurements were obtained through the International Physical Activity Questionnaire and World Health Organization Quality of Life-Bref. The sample was characterized by physically active adult male prosthetic users with positive quality of life, and amputation below the right knee caused by mechanical trauma related to traffic accidents with motorcycles. Significant correlations were identified between all domains of quality of life and between level of physical activity and psychological quality of life. No correlation was identified between gender and quality of life variables or physical activity levels. This study showed that in very active amputees of both genders, level of physical activity is not associated with quality of life except for the psychological domain.

Technology efficacy in active prosthetic knees for transfemoral amputees: a quantitative evaluation.

PubMed

El-Sayed, Amr M; Hamzaid, Nur Azah; Abu Osman, Noor Azuan

2014-01-01

Several studies have presented technological ensembles of active knee systems for transfemoral prosthesis. Other studies have examined the amputees' gait performance while wearing a specific active prosthesis. This paper combined both insights, that is, a technical examination of the components used, with an evaluation of how these improved the gait of respective users. This study aims to offer a quantitative understanding of the potential enhancement derived from strategic integration of core elements in developing an effective device. The study systematically discussed the current technology in active transfemoral prosthesis with respect to its functional walking performance amongst above-knee amputee users, to evaluate the system's efficacy in producing close-to-normal user performance. The performances of its actuator, sensory system, and control technique that are incorporated in each reported system were evaluated separately and numerical comparisons were conducted based on the percentage of amputees' gait deviation from normal gait profile points. The results identified particular components that contributed closest to normal gait parameters. However, the conclusion is limitedly extendable due to the small number of studies. Thus, more clinical validation of the active prosthetic knee technology is needed to better understand the extent of contribution of each component to the most functional development.

Fractal and twin SVM-based handgrip recognition for healthy subjects and trans-radial amputees using myoelectric signal.

PubMed

Arjunan, Sridhar Poosapadi; Kumar, Dinesh Kant; Jayadeva J

2016-02-01

Identifying functional handgrip patterns using surface electromygram (sEMG) signal recorded from amputee residual muscle is required for controlling the myoelectric prosthetic hand. In this study, we have computed the signal fractal dimension (FD) and maximum fractal length (MFL) during different grip patterns performed by healthy and transradial amputee subjects. The FD and MFL of the sEMG, referred to as the fractal features, were classified using twin support vector machines (TSVM) to recognize the handgrips. TSVM requires fewer support vectors, is suitable for data sets with unbalanced distributions, and can simultaneously be trained for improving both sensitivity and specificity. When compared with other methods, this technique resulted in improved grip recognition accuracy, sensitivity, and specificity, and this improvement was significant (κ=0.91).

Development of an externally powered prosthetic hook for amputees

NASA Technical Reports Server (NTRS)

Karchak, A., Jr.; Allen, J. R.; Bontrager, E. L.

1973-01-01

The powered hook with trigger finger appears to be a useful adaptation of a terminal device for an amputee when performing vocational activities involving the use of a powered tool requiring a trigger control. The proportional control system includes transducers and amplifiers and appears to have widespread application for control of any external power, whether it be in the orthotic or prosthetic field.

Standing on slopes - how current microprocessor-controlled prosthetic feet support transtibial and transfemoral amputees in an everyday task.

PubMed

Ernst, Michael; Altenburg, Björn; Bellmann, Malte; Schmalz, Thomas

2017-11-16

Conventional prosthetic feet like energy storage and return feet provide only a limited range of ankle motion compared to human ones. In order to overcome the poor rotational adaptability, prosthetic manufacturers developed different prosthetic feet with an additional rotational joint and implemented active control in different states. It was the aim of the study to investigate to what extent these commercially available microprocessor-controlled prosthetic feet support a natural posture while standing on inclines and which concept is most beneficial for lower limb amputees. Four unilateral transtibial and four unilateral transfemoral amputees participated in the study. Each of the subjects wore five different microprocessor-controlled prosthetic feet in addition to their everyday feet. The subjects were asked to stand on slopes of different inclinations (level ground, upward slope of 10°, and downward slope of -10°). Vertical ground reaction forces, joint torques and joint angles in the sagittal plane were measured for both legs separately for the different situations and compared to a non-amputee reference group. Differences in the biomechanical parameters were observed between the different prosthetic feet and compared to the reference group for the investigated situations. They were most prominent while standing on a downward slope. For example, on the prosthetic side, the vertical ground reaction force is reduced by about 20%, and the torque about the knee acts to flex the joint for feet that are not capable of a full adaptation to the downward slope. In contrast, fully adaptable feet with an auto-adaptive dorsiflexion stop show no changes in vertical ground reaction forces and knee extending torques. A prosthetic foot that provides both, an auto-adaptive dorsiflexion stop and a sufficient range of motion for fully adapting to inclinations appears to be the key element in the prosthetic fitting for standing on inclinations in lower limb amputees. In such situations, this prosthetic concept appears superior to both, conventional feet with passive structures as well as feet that solely provide a sufficient range of motion. The results also indicate that both, transfemoral and transtibial amputees benefit from such a foot.

Safety and function of a prototype microprocessor-controlled knee prosthesis for low active transfemoral amputees switching from a mechanic knee prosthesis: a pilot study.

PubMed

Hasenoehrl, Timothy; Schmalz, Thomas; Windhager, Reinhard; Domayer, Stephan; Dana, Sara; Ambrozy, Clemens; Palma, Stefano; Crevenna, Richard

2018-02-01

Aim of this pilot study was to assess safety and functioning of a microprocessor-controlled knee prosthesis (MPK) after a short familiarization time and no structured physical therapy. Five elderly, low-active transfemoral amputees who were fitted with a standard non-microprocessor controlled knee prosthesis (NMPK) performed a baseline measurement consisting of a 3 D gait analysis, functional tests and questionnaires. The first follow-up consisted of the same test procedure and was performed with the MPK after 4 to 6 weeks of familiarization. After being refitted to their standard NMPK again, the subjects undertook the second follow-up which consisted of solely questionnaires 4 weeks later. Questionnaires and functional tests showed an increase in the perception of safety. Moreover, gait analysis revealed more physiologic knee and hip extension/flexion patterns when using the MPK. Our results showed that although the Genium with Cenior-Leg ruleset-MPK (GCL-MPK) might help to improve several safety-related outcomes as well as gait biomechanics the functional potential of the GCL-MPK may have been limited without specific training and a sufficient acclimation period. Implications for Rehabilitation Elderly transfemoral amputees are often limited in their activity by safety issues as well as insufficient functioning regarding the non microprocessor-controlled knee prostheses (NMPK), thing that could be eliminated with the use of suitable microprocessor-controlled prostheses (MPK). The safety and functioning of a prototype MPK (GCL-MPK) specifically designed for the needs of older and low-active transfemoral amputees was assessed in this pilot study. The GCL-MPK showed indicators of increased safety and more natural walking patterns in older and low-active transfemoral amputees in comparison to the standard NMPK already after a short acclimatisation time and no structured physical therapy. Regarding functional performance it seems as if providing older and low-active transfemoral amputees with the GCL-MPK alone without prescribing structured prosthesis training might be insufficient to achieve improvements over the standard NMPKs.

Longitudinal kinematic and kinetic adaptations to obstacle crossing in recent lower limb amputees.

PubMed

Barnett, Cleveland T; Polman, Remco C J; Vanicek, Natalie

2014-12-01

Obstacle crossing is an important activity of daily living, necessary to avoid tripping or falling, although it is not fully understood how transtibial amputees adapt to performing this activity of daily living following discharge from rehabilitation. The objective of this study was to investigate the longitudinal adaptations in obstacle crossing in transtibial amputees post-discharge from rehabilitation. Longitudinal repeated measures. Seven unilateral transtibial amputees crossed an obstacle 0.1m high positioned along a walkway while kinematic and kinetic data were recorded at 1, 3 and 6 months post-discharge. At 6 months post-discharge, walking velocity had increased (0.17 m.s(-1)) with most participants self-selecting an intact lead limb preference. During swing phase, peak knee flexion (p = 0.03) and peak knee power absorption (K4; p = 0.01) were greater with an intact versus affected lead limb preference. Having crossed the obstacle, intact limb peak ankle power generation in pre-swing (A2; p = 0.01) and knee power absorption (K3; p = 0.05) during stance phase were greater when compared to the affected limb. Obstacle crossing improved, although a greater reliance on intact limb function was highlighted. Results suggested that further improvements to locomotor performance may be obtained by increasing affected limb knee range of motion and concentric and eccentric strength of the knee extensors and flexors. The novel objective data from this study establish an understanding of how recent transtibial amputees adapt to performing obstacle crossing following discharge from rehabilitation. This allows for evidence-based clinical interventions to be developed, aimed at optimising biomechanical function, thus improving overall locomotor performance and perhaps subsequent quality of life. © The International Society for Prosthetics and Orthotics 2013.

Patellofemoral arthroplasty in a bilateral Syme's amputee.

PubMed

Kanna, Raj; Barrett, David S

2016-01-01

We present the case of a 50-year-old woman, who is a bilateral Syme's amputee and subsequently underwent patellofemoral arthroplasty (PFA) for osteoarthritis primarily involving the patellofemoral (PF) joint. History and physical examination were suggestive of severe PF arthritis without patellar instability of the right knee. The diagnosis was confirmed by roentgenogram and a PFA was performed. A slightly modified rehabilitation program was implemented and the patient was followed until 6 years after surgery. In comparison to the preoperative scores, the Oxford, the Western Ontario and McMaster Universities (WOMAC), the Knee Society, and the Hospital for Special Surgery Knee Scores improved significantly (p < 0.05) at the time of final follow-up. PF problems specific to below-knee amputees, factors to be considered before performing PFA, and the drawbacks of other treatment modalities in these patients have been discussed.

Challenges of CPD for physiotherapists working as lone practitioners in amputee rehabilitation.

PubMed

Cole, Mary Jane; Morris, Jane; Scammell, Amy

2008-09-01

The aim of this study was to explore the issues around continuing professional development (CPD) for physiotherapists working as lone practitioners in amputee rehabilitation in the United Kingdom (UK). Qualitative method using a phenomenological approach via one to one semi-structured interviews and thematic data analysis. Ten physiotherapists with responsibility for amputee rehabilitation working as lone practitioners in hospitals or specialist centres in the UK. CPD is valued and there is commitment towards the process. Current solutions are identified but there are frustrations around more structured CPD and organizational issues. These include inadequate access to learning opportunities, lack of professional feedback, insufficient time and limited learning skills. There are opportunities for improving CPD through organizational structures but specialist input is recommended to support lone practitioners and managers with the process, e.g., consultant or peripatetic therapists.

Building a successful support group for post-amputation patients.

PubMed

Marzen-Groller, Karen; Bartman, Kimberly

2005-06-01

The purpose of this article is to identify five steps to attain a successful amputee support group and share the process for establishing and maintaining a peer visitation program for in-patient amputees. Whatever the cause, losing a limb is a life-changing event that one should not go through alone. Support groups can assist patients and their families through this transition in a positive and healthy way.

Online myoelectric control of a dexterous hand prosthesis by transradial amputees.

PubMed

Cipriani, Christian; Antfolk, Christian; Controzzi, Marco; Lundborg, Göran; Rosen, Birgitta; Carrozza, Maria Chiara; Sebelius, Fredrik

2011-06-01

A real-time pattern recognition algorithm based on k-nearest neighbors and lazy learning was used to classify, voluntary electromyography (EMG) signals and to simultaneously control movements of a dexterous artificial hand. EMG signals were superficially recorded by eight pairs of electrodes from the stumps of five transradial amputees and forearms of five able-bodied participants and used online to control a robot hand. Seven finger movements (not involving the wrist) were investigated in this study. The first objective was to understand whether and to which extent it is possible to control continuously and in real-time, the finger postures of a prosthetic hand, using superficial EMG, and a practical classifier, also taking advantage of the direct visual feedback of the moving hand. The second objective was to calculate statistical differences in the performance between participants and groups, thereby assessing the general applicability of the proposed method. The average accuracy of the classifier was 79% for amputees and 89% for able-bodied participants. Statistical analysis of the data revealed a difference in control accuracy based on the aetiology of amputation, type of prostheses regularly used and also between able-bodied participants and amputees. These results are encouraging for the development of noninvasive EMG interfaces for the control of dexterous prostheses.

Mechanisms of Gait Asymmetry Due to Push-Off Deficiency in Unilateral Amputees.

PubMed

Adamczyk, Peter Gabriel; Kuo, Arthur D

2015-09-01

Unilateral lower-limb amputees exhibit asymmetry in many gait features, such as ground force, step time, step length, and joint mechanics. Although these asymmetries result from weak prosthetic-side push-off, there is no proven mechanistic explanation of how that impairment propagates to the rest of the body. We used a simple dynamic walking model to explore possible consequences of a unilateral impairment similar to that of a transtibial amputee. The model compensates for reduced push-off work from one leg by performing more work elsewhere, for example during the middle of stance by either or both legs. The model predicts several gait abnormalities, including slower forward velocity of the body center-of-mass during intact-side stance, greater energy dissipation in the intact side, and more positive work overall. We tested these predictions with data from unilateral transtibial amputees (N = 11) and nonamputee control subjects (N = 10) walking on an instrumented treadmill. We observed several predicted asymmetries, including forward velocity during stance phases and energy dissipation from the two limbs, as well as greater work overall. Secondary adaptations, such as to reduce discomfort, may exacerbate asymmetry, but these simple principles suggest that some asymmetry may be unavoidable in cases of unilateral limb loss.

Vibrotactile stimulation promotes embodiment of an alien hand in amputees with phantom sensations.

PubMed

D'Alonzo, Marco; Clemente, Francesco; Cipriani, Christian

2015-05-01

Tactile feedback is essential to intuitive control and to promote the sense of self-attribution of a prosthetic limb. Recent findings showed that amputees can be tricked to experience this embodiment, when synchronous and modality-matched stimuli are delivered to biological afferent structures and to an alien rubber hand. Hence, it was suggested to exploit this effect by coupling touch sensors in a prosthesis to an array of haptic tactile stimulators in the prosthetic socket. However, this approach is not clinically viable due to physical limits of current haptic devices. To address this issue we have proposed modality-mismatched stimulation and demonstrated that this promotes self-attribution of an alien hand on normally limbed subjects. In this work we investigated whether similar effects could be induced in transradial amputees with referred phantom sensations in a series of experiments fashioned after the Rubber Hand Illusion using vibrotactile stimulators. Results from three independent measures of embodiment demonstrated that vibrotactile sensory substitution elicits body-ownership of a rubber hand in transradial amputees. These results open up promising possibilities in this field; indeed miniature, safe and inexpensive vibrators could be fitted into commercially available prostheses and sockets to induce the illusion every time the prosthesis manipulates an object.

The effect of segmental weight of prosthesis on hemodynamic responses and energy expenditure of lower extremity amputees

PubMed Central

Mutlu, Akmer; Kharooty, Mohammad Dawood; Yakut, Yavuz

2017-01-01

[Purpose] The aim of this study was to investigate the effect of segmental weight of the prosthesis on hemodynamic responses and energy expenditure in lower extremity amputees. [Subjects and Methods] Thirteen patients with a mean age of 44 ± 15.84 years and with unilateral transtibial, transfemoral and Syme’s amputation were included to the study. The difference between the lightest and the heaviest prosthesis, 250 g used as the weight. All the patients completed the measurements first without weight and then with 250 g weight on the ankle joint. The blood pressure and heart rate of the patients were recorded before and after Six Minute Walk Test (6MWT) and 10 stairs up & down stairs test. Physiological Cost Index was used to calculate the energy expenditure. [Results] Heart rate and energy expenditure increased significantly when without weight and with weight results compared. [Conclusion] We conclude that the segmental weight of the prosthetic limb has a significant effect on the heart rate and energy expenditure but has no effect on the systolic and diastolic blood pressure of lower limb amputees. In order to generalize our results to lower limb amputees, more patients need to be included in future studies. PMID:28533599

Technology Efficacy in Active Prosthetic Knees for Transfemoral Amputees: A Quantitative Evaluation

PubMed Central

El-Sayed, Amr M.; Abu Osman, Noor Azuan

2014-01-01

Several studies have presented technological ensembles of active knee systems for transfemoral prosthesis. Other studies have examined the amputees' gait performance while wearing a specific active prosthesis. This paper combined both insights, that is, a technical examination of the components used, with an evaluation of how these improved the gait of respective users. This study aims to offer a quantitative understanding of the potential enhancement derived from strategic integration of core elements in developing an effective device. The study systematically discussed the current technology in active transfemoral prosthesis with respect to its functional walking performance amongst above-knee amputee users, to evaluate the system's efficacy in producing close-to-normal user performance. The performances of its actuator, sensory system, and control technique that are incorporated in each reported system were evaluated separately and numerical comparisons were conducted based on the percentage of amputees' gait deviation from normal gait profile points. The results identified particular components that contributed closest to normal gait parameters. However, the conclusion is limitedly extendable due to the small number of studies. Thus, more clinical validation of the active prosthetic knee technology is needed to better understand the extent of contribution of each component to the most functional development. PMID:25110727

Patellofemoral arthroplasty in a bilateral Syme's amputee

PubMed Central

Kanna, Raj; Barrett, David S.

2016-01-01

We present the case of a 50-year-old woman, who is a bilateral Syme's amputee and subsequently underwent patellofemoral arthroplasty (PFA) for osteoarthritis primarily involving the patellofemoral (PF) joint. History and physical examination were suggestive of severe PF arthritis without patellar instability of the right knee. The diagnosis was confirmed by roentgenogram and a PFA was performed. A slightly modified rehabilitation program was implemented and the patient was followed until 6 years after surgery. In comparison to the preoperative scores, the Oxford, the Western Ontario and McMaster Universities (WOMAC), the Knee Society, and the Hospital for Special Surgery Knee Scores improved significantly (p < 0.05) at the time of final follow-up. PF problems specific to below-knee amputees, factors to be considered before performing PFA, and the drawbacks of other treatment modalities in these patients have been discussed. PMID:26908975

Expert opinions on success factors for upper-limb prostheses.

PubMed

Schultz, Aimee E; Baade, Susan P; Kuiken, Todd A

2007-01-01

The goal of this study was to gather the opinions of prosthetics experts on the most important factors for the successful use of upper-limb (UL) prostheses, compare them with those of prosthesis users, and ultimately direct research efforts in this field. UL prosthetics experts were asked to compare the importance of the comfort, function, and cosmesis of a prosthetic device for a transhumeral amputee. Categories were subdivided into weight, socket-interface comfort, power, agility, color, and shape. The majority of those who responded viewed comfort as the most important factor for a unilateral amputee and considered socket-interface comfort to be more important than weight. Function was considered to be the most important factor for a bilateral amputee, with agility considered more important than power. Cosmesis was consistently reported as being less important than comfort and function, and shape was considered more important than color.

Normal body scheme and absent phantom limb experience in amputees while dreaming.

PubMed

Alessandria, Maria; Vetrugno, Roberto; Cortelli, Pietro; Montagna, Pasquale

2011-12-01

While dreaming amputees often experience a normal body image and the phantom limb may not be present. However, dreaming experiences in amputees have mainly been collected by questionnaires. We analysed the dream reports of amputated patients with phantom limb collected after awakening from REM sleep during overnight videopolysomnography (VPSG). Six amputated patients underwent overnight VPSG study. Patients were awakened during REM sleep and asked to report their dreams. Three patients were able to deliver an account of a dream. In all dreaming recalls, patients reported that the amputated limbs were intact and completely functional and they no longer experienced phantom limb sensations. Phantom limb experiences, that during wake result from a conflict between a pre-existing body scheme and the sensory information on the missing limb, were suppressed during sleep in our patients in favour of the image of an intact body accessed during dream. Copyright © 2011 Elsevier Inc. All rights reserved.

Survival rates in dysvascular lower limb amputees.

PubMed

Kulkarni, J; Pande, S; Morris, J

2006-01-01

To assess the 5-year and 10-year survival rates of major (above ankle disarticulation level) dysvascular lower limb amputees attending a sub-regional Disablement Services Centre (DSC) specialising in amputee rehabilitation. Also to investigate the association between survival rates, cause of dysvascularity, level of amputation, smoking status and occupational status. The study was undertaken in sub-regional DSC for amputee rehabilitation covering a base population of about 3.5million people. Over 80% of lower limb amputations were done for dysvascularity (peripheral vascular disease, diabetic or combination). All these patients were followed up in the DSC for their prosthetic/amputee rehabilitation. Modular case records of 201 consecutive patients from 1994 to 1995 who had diagnosis of dysvascularity as the cause of major lower limb amputations, were scrutinised regarding their 10-year survival; demographic details, level of lower limb amputations, Above Knee (AK=Transfemoral), Below Knee (BK=Transtibial), smoking status, occupational status, healing of the stump at first assessment, cause of amputation and association of these factors with survival rates. Of 201 individuals with either AK or BK amputations, 60% (121) had AK amputations and 67% (134) were males, the mean age was 69years of age. Sixty-seven percent (97) had history of smoking, either current 43% (62) or prior 24% (35) smoking, and 59% (68) were skilled or non-skilled manual workers. Fifty-one percent (99) had diagnosis of peripheral vascular disease, whilst 34% (65) had combination of peripheral vascular disease and diabetes, diabetes on its own in 4% (7). In 12% (23) other causes were noted such as embolism, acute ischaemia, venous ulcers, etc. Regarding stumps healing at first assessment, healing was noted in 54% (109) whilst stump was unhealed in 46% (92). The median survival was 48months. Using Cox proportional hazards regression to identify association with survival, the hazard ratio (HR) was significant regarding level of amputation: HR 2.34; 95% confidence interval (CI) (1.58, 3.47), P<0.001 (a recent BK amputation increases the risk by 2.3 compared to a recent AK amputation in diabetic cohort and also in the peripheral vascular disease/diabetes cohort). Hazard ratio was less than 1.0 in bilateral amputees: HR 0.35, 95% CI (0.21, 0.60), P<0.001 (bilateral amputation decreases risk by 0.35). Our study indicates that the median survival remains at 4years, which is similar to the previously published evidence in the Finish study of 1998 and the earlier study from Scotland in 1992. Unlike the previous data, our study indicates that patients with BK amputations have a higher hazard ratio than the AK amputees, and an association with diabetes has poorer prognosis regarding survival.

Somatotopical feedback versus non-somatotopical feedback for phantom digit sensation on amputees using electrotactile stimulation.

PubMed

Zhang, Dingguo; Xu, Heng; Shull, Peter B; Liu, Jianrong; Zhu, Xiangyang

2015-05-02

Transcutaneous electrical stimulation can provide amputees with tactile feedback for better manipulating an advanced prosthesis. In general, there are two ways to transfer the stimulus to the skin: somatotopical feedback (SF) that stimulates the phantom digit somatotopy on the stump and non-somatotopical feedback (NF) that stimulates other positions on the human body. To investigate the difference between SF and NF, electrotactile experiments were conducted on seven amputees. Electrical stimulation was applied via a complete phantom map to the residual limb (SF) and to the upper arm (NF) separately. The behavior results of discrimination accuracy and response time were used to examine: 1) performance differences between SF and NF for discriminating position, type and strength of tactile feedback; 2) performance differences between SF and NF for one channel (1C), three channels (3C), and five channels (5C). NASA-TLX standardized testing was used to determine differences in mental workload between SF and NF. The grand-averaged discrimination accuracy for SF was 6% higher than NF, and the average response time for SF was 600 ms faster than NF. SF is better than NF for position, type, strength, and the overall modality regarding both accuracy and response time except for 1C modality (p<0.001). Among the six modalities of stimulation channels, performance of 1C/SF was the best, which was similar to that of 1C/NF and 3C/SF; performance of 3C/NF was similar to that of 5C/SF; performance of 5C/NF was the worst. NASA-TLX scores indicated that mental workload increased as the number of stimulation channels increased. We quantified the difference between SF and NF, and the influence of different number of stimulation channels. SF was better than NF in general, but the practical issues such as the limited area of stumps could constrain the use of SF. We found that more channels increased the amount and richness of information to the amputee while fewer channels resulted in higher performance, and thus the 3C/SF modality was a good compromise. Based on this study, we provide possible solutions to the practical problems involving the implementation of tactile feedback for amputees. These results are expected to promote the application of SF and NF tactile feedback for amputees in the future.

Joint Loads and Cartilage Stress in Intact Joints of Military Transtibial Amputees: Enhancing Quality of Life

DTIC Science & Technology

2017-04-01

crosstalk); analysis of tested subjects underway. 4) Developed analytical methods to obtain knee joint loads using EMG-driven inverse dynamics; analysis of...13/2018. Completion %: 40. Task 1.3: EMG-driven inverse dynamic (ID) analyses with OpenSim for amputee and control group subjects. Target date: 1...predicted by EMG-driven inverse dynamics. Two-three conference papers are being prepared for submission in February 2017. Other achievements. None

User intent prediction with a scaled conjugate gradient trained artificial neural network for lower limb amputees using a powered prosthesis.

PubMed

Woodward, Richard B; Spanias, John A; Hargrove, Levi J

2016-08-01

Powered lower limb prostheses have the ability to provide greater mobility for amputee patients. Such prostheses often have pre-programmed modes which can allow activities such as climbing stairs and descending ramps, something which many amputees struggle with when using non-powered limbs. Previous literature has shown how pattern classification can allow seamless transitions between modes with a high accuracy and without any user interaction. Although accurate, training and testing each subject with their own dependent data is time consuming. By using subject independent datasets, whereby a unique subject is tested against a pooled dataset of other subjects, we believe subject training time can be reduced while still achieving an accurate classification. We present here an intent recognition system using an artificial neural network (ANN) with a scaled conjugate gradient learning algorithm to classify gait intention with user-dependent and independent datasets for six unilateral lower limb amputees. We compare these results against a linear discriminant analysis (LDA) classifier. The ANN was found to have significantly lower classification error (P<;0.05) than LDA with all user-dependent step-types, as well as transitional steps for user-independent datasets. Both types of classifiers are capable of making fast decisions; 1.29 and 2.83 ms for the LDA and ANN respectively. These results suggest that ANNs can provide suitable and accurate offline classification in prosthesis gait prediction.

A pressure and shear sensor system for stress measurement at lower limb residuum/socket interface.

PubMed

Laszczak, P; McGrath, M; Tang, J; Gao, J; Jiang, L; Bader, D L; Moser, D; Zahedi, S

2016-07-01

A sensor system for measurement of pressure and shear at the lower limb residuum/socket interface is described. The system comprises of a flexible sensor unit and a data acquisition unit with wireless data transmission capability. Static and dynamic performance of the sensor system was characterised using a mechanical test machine. The static calibration results suggest that the developed sensor system presents high linearity (linearity error ≤ 3.8%) and resolution (0.9 kPa for pressure and 0.2 kPa for shear). Dynamic characterisation of the sensor system shows hysteresis error of approximately 15% for pressure and 8% for shear. Subsequently, a pilot amputee walking test was conducted. Three sensors were placed at the residuum/socket interface of a knee disarticulation amputee and simultaneous measurements were obtained during pilot amputee walking test. The pressure and shear peak values as well as their temporal profiles are presented and discussed. In particular, peak pressure and shear of approximately 58 kPa and 27 kPa, respectively, were recorded. Their temporal profiles also provide dynamic coupling information at this critical residuum/socket interface. These preliminary amputee test results suggest strong potential of the developed sensor system for exploitation as an assistive technology to facilitate socket design, socket fit and effective monitoring of lower limb residuum health. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Use of prostheses in lower limb amputee patients due to peripheral arterial disease

PubMed Central

Chamlian, Therezinha Rosane

2014-01-01

Objective To evaluate the indication of prosthesis during rehabilitation and the maintenance of their use or abandonment rate after discharge, as well as mortality of lower limb amputees due to peripheral arterial disease. Methods A retrospective and cross-sectional study carried out with lower limb amputee patients, at transfemoral and transtibial levels, due to vascular conditions. The sample was composed of 310 patients (205 men, 105 women, mean age 61.8 years), transfemoral (142) and transtibial (150) levels, unilateral or bilateral (18). A total of 217 were fitted with prosthesis and 93 did not. Nonparametric statistical tests with equality of two proportions, 95% confidence interval and p value <0,05 were used. Results Out of 195 patients we contacted, 151 were fitted with prosthesis and 44 not. Of those that were fitted with prosthesis, 54 still use it, 80 abandoned and 17 died. In the group without prosthesis, 27 were on wheelchair and 17 died. Mortality is statistically higher among patients who were not fitted with prosthesis and 34 death occur, on average, 3.91 years after amputation. Survival time of patients who were not fitted with prosthesis was smaller than those were fitted. Conclusion The use of prosthesis in lower limb amputees, due to vascular conditions, during rehabilitation is high. However, maintenance of prosthesis is not frequent after discharge. Early and high mortality is observed mainly among diabetic patients. PMID:25628194

Kinetics of transfemoral amputees with osseointegrated fixation performing common activities of daily living.

PubMed

Lee, Winson C C; Frossard, Laurent A; Hagberg, Kerstin; Haggstrom, Eva; Brånemark, Rickard; Evans, John H; Pearcy, Mark J

2007-07-01

Direct anchorage of a lower-limb prosthesis to the bone through an implanted fixation (osseointegration) has been suggested as an excellent alternative for amputees experiencing complications from use of a conventional socket-type prosthesis. However, an attempt needs to be made to optimize the mechanical design of the fixation and refine the rehabilitation program. Understanding the load applied on the fixation is a crucial step towards this goal. The load applied on the osseointegrated fixation of nine transfemoral amputees was measured using a load transducer, when the amputees performed activities which included straight-line level walking, ascending and descending stairs and a ramp as well as walking around a circle. Force and moment patterns along each gait cycle, magnitudes and time of occurrence of the local extrema of the load, as well as impulses were analysed. Managing a ramp and stairs, and walking around a circle did not produce a significant increase (P>0.05) in load compared to straight-line level walking. The patterns of the moment about the medio-lateral axis were different among the six activities which may reflect the different strategies used in controlling the prosthetic knee joint. This study increases the understanding of biomechanics of bone-anchored osseointegrated prostheses. The loading data provided will be useful in designing the osseointegrated fixation to increase the fatigue life and to refine the rehabilitation protocol.

Prosthesis use in adult acquired major upper-limb amputees: patterns of wear, prosthetic skills and the actual use of prostheses in activities of daily life.

PubMed

Østlie, Kristin; Lesjø, Ingrid Marie; Franklin, Rosemary Joy; Garfelt, Beate; Skjeldal, Ola Hunsbeth; Magnus, Per

2012-11-01

To describe patterns of prosthesis wear and perceived prosthetic usefulness in adult acquired upper-limb amputees (ULAs). To describe prosthetic skills in activities of daily life (ADL) and the actual use of prostheses in the performance of ADL tasks. To estimate the influence of prosthetic skills on actual prosthesis use and the influence of background factors on prosthetic skills and actual prosthesis use. Cross-sectional study analysing population-based questionnaire data (n = 224) and data from interviews and clinical testing in a referred/convenience sample of prosthesis-wearing ULAs (n = 50). Effects were analysed using linear regression. 80.8% wore prostheses. 90.3% reported their most worn prosthesis as useful. Prosthetic usefulness profiles varied with prosthetic type. Despite demonstrating good prosthetic skills, the amputees reported actual prosthesis use in only about half of the ADL tasks performed in everyday life. In unilateral amputees, increased actual use was associated with sufficient prosthetic training and with the use of myoelectric vs cosmetic prostheses, regardless of amputation level. Prosthetic skills did not affect actual prosthesis use. No background factors showed significant effect on prosthetic skills. Most major ULAs wear prostheses. Individualised prosthetic training and fitting of myoelectric rather than passive prostheses may increase actual prosthesis use in ADL.

Spatiotemporal Variables of Able-bodied and Amputee Sprinters in Men's 100-m Sprint.

PubMed

Hobara, H; Kobayashi, Y; Mochimaru, M

2015-06-01

The difference in world records set by able-bodied sprinters and amputee sprinters in the men's 100-m sprint is still approximately 1 s (as of 28 March 2014). Theoretically, forward velocity in a 100-m sprint is the product of step frequency and step length. The goal of this study was to examine the hypothesis that differences in the sprint performance of able-bodied and amputee sprinters would be due to a shorter step length rather than lower step frequency. Men's elite-level 100-m races with a total of 36 able-bodied, 25 unilateral and 17 bilateral amputee sprinters were analyzed from the publicly available internet broadcasts of 11 races. For each run of each sprinter, the average forward velocity, step frequency and step length over the whole 100-m distance were analyzed. The average forward velocity of able-bodied sprinters was faster than that of the other 2 groups, but there was no significant difference in average step frequency among the 3 groups. However, the average step length of able-bodied sprinters was significantly longer than that of the other 2 groups. These results suggest that the differences in sprint performance between 2 groups would be due to a shorter step length rather than lower step frequency. © Georg Thieme Verlag KG Stuttgart · New York.

Management of the multiple limb amputee.

PubMed

Davidson, J H; Jones, L E; Cornet, J; Cittarelli, T

2002-09-10

Multiple limb amputations involving at least one upper extremity are very uncommon. The amputation of both an upper and lower limb is even more uncommon. Due to the rarity of these amputations therapists are uncertain regarding the most appropriate treatment methods. While the majority of the protocols used for single limb amputations are appropriate for these multiple limb amputees, there are differences. Loss of multiple limbs creates a problem of overheating for the individual. Loss of an arm and leg results in difficulty donning the prostheses and difficulty using crutches and parallel bars during mobilization. A review is given of 16 multiple limb amputees seen in our rehabilitation centre in the last 15 years. Return to work was seen in one third and was not related to the number of the amputations. A higher proportion of these multiple limb amputations occur through alcoholism or attempted suicide behaviour than occurs with either single upper limb amputations or lower limb amputations. This existing behaviour can create a management problem for the rehabilitation team during rehabilitation. Guidelines as to appropriate prosthetic and preprosthetic care are provided to assist the practitioner who has the acute and long term care of these patients. All multiple limb amputees should be referred to a specialized rehabilitation centre to discuss prosthetic options and long term rehabilitation requirements. This paper does not discuss bilateral lower limb amputations when not combined with an upper limb amputation.

Return-to-duty rates among US military combat-related amputees in the global war on terror: job description matters.

PubMed

Belisle, Jeffery G; Wenke, Joseph C; Krueger, Chad A

2013-08-01

The purpose of this study was to identify the differences seen between military occupation services (MOS) in terms of amputation patterns, subsequent disabling conditions, and their ability to return to duty. A retrospective study of major extremity amputations sustained by US service members between October 1, 2001, and July 30, 2011, was performed. Data obtained from the amputation database, Joint Trauma Theater Database, and the Physical Evaluation Board Liaison Office included demographics, amputation location(s), Injury Severity Scores (ISSs), disabling conditions, disability ratings, and disposition status. There were 1,221 major extremity amputees identified during the specified time frame, of which 899 had data regarding disabling conditions, ratings, and disposition. All service branches were represented. Personnel from the US Army (USA) Infantry were significantly (p < 0.0001) more likely to sustain an amputation than other MOS. The USA Infantry, the US Marine Corps Infantry and the USA Armor represented the top three specialties and accounted for more than 57% of all amputees. Approximately 89% of all service members did not return to duty, and the mean combined for all amputees was 76. USA Special Forces (USA SF) operators were significantly more likely to return to duty (p = 0.0022) and be found fit for duty (p = 0.0015) than all other MOS despite having a mean ISS (20) that was no different from those of other service members. No USA SF personnel were found to have posttraumatic stress disorder as a disabling condition. All amputees, regardless of MOS, are not likely to return to active duty and especially unlikely to be found fit for duty, except for members of the USA SF. The reason(s) for the increased return to duty for USA SF personnel remains unknown but a lack of posttraumatic stress disorder may be a contributing factor.

Assessment of transfemoral amputees using a passive microprocessor-controlled knee versus an active powered microprocessor-controlled knee for level walking.

PubMed

Creylman, Veerle; Knippels, Ingrid; Janssen, Paul; Biesbrouck, Evelyne; Lechler, Knut; Peeraer, Louis

2016-12-19

In transfemoral (TF) amputees, the forward propulsion of the prosthetic leg in swing has to be mainly carried out by hip muscles. With hip strength being the strongest predictor to ambulation ability, an active powered knee joint could have a positive influence, lowering hip loading and contributing to ambulation mobility. To assess this, gait of four TF amputees was measured for level walking, first while using a passive microprocessor-controlled prosthetic knee (P-MPK), subsequently while using an active powered microprocessor-controlled prosthetic knee (A-MPK). Furthermore, to assess long-term effects of the use of an A-MPK, a 4-weeks follow-up case study was performed. The kinetics and kinematics of the gait of four TF amputees were assessed while walking with subsequently the P-MPK and the A-MPK. For one amputee, a follow-up study was performed: he used the A-MPK for 4 weeks, his gait was measured weekly. The range of motion of the knee was higher on both the prosthetic and the sound leg in the A-MPK compared to the P-MPK. Maximum hip torque (HT) during early stance increased for the prosthetic leg and decreased for the sound leg with the A-MPK compared to the P-MPK. During late stance, the maximum HT decreased for the prosthetic leg. The difference between prosthetic and sound leg for HT disappeared when using the A-MPK. Also, an increase in stance phase duration was observed. The follow-up study showed an increase in confidence with the A-MPK over time. Results suggested that, partially due to an induced knee flexion during stance, HT can be diminished when walking with the A-MPK compared to the P-MPK. The single case follow-up study showed positive trends indicating that an adaptation time is beneficial for the A-MPK.

Powered ankle-foot prosthesis to assist level-ground and stair-descent gaits.

PubMed

Au, Samuel; Berniker, Max; Herr, Hugh

2008-05-01

The human ankle varies impedance and delivers net positive work during the stance period of walking. In contrast, commercially available ankle-foot prostheses are passive during stance, causing many clinical problems for transtibial amputees, including non-symmetric gait patterns, higher gait metabolism, and poorer shock absorption. In this investigation, we develop and evaluate a myoelectric-driven, finite state controller for a powered ankle-foot prosthesis that modulates both impedance and power output during stance. The system employs both sensory inputs measured local to the external prosthesis, and myoelectric inputs measured from residual limb muscles. Using local prosthetic sensing, we first develop two finite state controllers to produce biomimetic movement patterns for level-ground and stair-descent gaits. We then employ myoelectric signals as control commands to manage the transition between these finite state controllers. To transition from level-ground to stairs, the amputee flexes the gastrocnemius muscle, triggering the prosthetic ankle to plantar flex at terminal swing, and initiating the stair-descent state machine algorithm. To transition back to level-ground walking, the amputee flexes the tibialis anterior muscle, triggering the ankle to remain dorsiflexed at terminal swing, and initiating the level-ground state machine algorithm. As a preliminary evaluation of clinical efficacy, we test the device on a transtibial amputee with both the proposed controller and a conventional passive-elastic control. We find that the amputee can robustly transition between the finite state controllers through direct muscle activation, allowing rapid transitioning from level-ground to stair walking patterns. Additionally, we find that the proposed finite state controllers result in a more biomimetic ankle response, producing net propulsive work during level-ground walking and greater shock absorption during stair descent. The results of this study highlight the potential of prosthetic leg controllers that exploit neural signals to trigger terrain-appropriate, local prosthetic leg behaviors.

Characterization of disability following traumatic through knee and transfemoral amputations.

PubMed

Tennent, David J; Polfer, Elizabeth M; Sgromolo, Nicole M; Krueger, Chad A; Potter, Benjamin K

2018-06-01

The purpose of this study is to characterize through knee and transfemoral amputations following severe traumatic injuries. A retrospective review of all transfemoral and through knee amputations sustained by United States military service members from 1 October 2001 to 30 July 2011 was conducted. Data from the Department of Defense Trauma Registry, the Armed Forces Health Longitudinal Technology Application, inpatient medical records and the Physical Evaluation Board Liaison Offices were queried in order to obtain characteristics related to injury sustained, demographics, treatment, and disability/mental health outcome data. A total of 1631 amputations in 1315 patients were identified. Of these there were 37 through knee and 296 were transfemoral amputations. Adequate records for detailed analysis were available on 140 and 25 transfemoral and through knee amputations respectively. There were no significant differences in demographic information, injury mechanism, initial injury severity score, or associated injuries, to include contralateral amputations. There was no significant difference in average disability rating (67.9% vs 78.3%, p = 0.46) or number of service members determined to be fully disabled (42.2% vs 28.6% p = 0.33) between the transfemoral and through knee amputation groups. Whereas there was no difference between groups preoperatively, the knee disarticulation group displayed a higher rate of mental health diagnoses post-amputation (96% vs 72%, p < 0.001) and a higher preponderance of anxiety related disorders than the transfemoral amputees (26.92% vs 12.96%, p = 0.0129). Among this military amputee through knee and transfemoral amputees displayed similar physical disability profiles. However, the through knee amputees displayed a higher level of anxiety related disorders and mental health diagnosis overall. While we don't believe this relationship to be causal in nature, this finding reflects the importance of paying particular attention to mental health in the final disposition of traumatic lower extremity amputees. Published by Elsevier Ltd.

Current perspective on assessment of human body proportions of relevance to amputees.

PubMed

Osterkamp, L K

1995-02-01

Weights of segmental components of the human body are important when evaluating the nutritional status of an amputee. Original standards for components were compiled in 1889 using three male cadavers. Since that time, studies of living subjects have shown men and women to be similar in percentage weight of body components. Cadaver data from 1955 and 1969, which were based on 21 male subjects, showed that human bodies carry greater weight in the head and torso and less weight in legs and arms than indicated by the earlier data. Some differences in component weight may be attributable to ethnicity and aging, but further research is needed to define these differences. The 1955 and 1969 data--whether the result of larger sample size, ethnic differences, or actual change in human body proportions over a 60-year period--are different from the standards for body proportions in the 1889 data, which are presently used, and should be incorporated into the assessment of weight status of amputees.

Virtual Constraint Control of a Powered Prosthetic Leg: From Simulation to Experiments with Transfemoral Amputees.

PubMed

Gregg, Robert D; Lenzi, Tommaso; Hargrove, Levi J; Sensinger, Jonathon W

2014-12-01

Recent powered (or robotic) prosthetic legs independently control different joints and time periods of the gait cycle, resulting in control parameters and switching rules that can be difficult to tune by clinicians. This challenge might be addressed by a unifying control model used by recent bipedal robots, in which virtual constraints define joint patterns as functions of a monotonic variable that continuously represents the gait cycle phase. In the first application of virtual constraints to amputee locomotion, this paper derives exact and approximate control laws for a partial feedback linearization to enforce virtual constraints on a prosthetic leg. We then encode a human-inspired invariance property called effective shape into virtual constraints for the stance period. After simulating the robustness of the partial feedback linearization to clinically meaningful conditions, we experimentally implement this control strategy on a powered transfemoral leg. We report the results of three amputee subjects walking overground and at variable cadences on a treadmill, demonstrating the clinical viability of this novel control approach.

A Powered Prosthetic Intervention for Bilateral Transfemoral Amputees

PubMed Central

Lawson, Brian E.; Ruhe, Brian; Shultz, Amanda; Goldfarb, Michael

2014-01-01

This paper presents the design and validation of a control system for a pair of powered knee and ankle prostheses to be used as a prosthetic intervention for bilateral transfemoral amputees. The control system leverages communication between the prostheses for enhanced awareness and stability, along with power generation at the knee and ankle joints to better restore biomechanical functionality in level ground walking. The control methodology employed is a combination of an impedance-based framework for weight-bearing portions of gait and a trajectory-based approach for the non-weight-bearing portions. The control system was implemented on a pair of self-contained powered knee and ankle prostheses, and the ability of the prostheses and control approach to provide walking functionality was assessed in a set of experimental trials with a bilateral transfemoral amputee subject. Specifically, experimental data from these trials indicate that the powered prostheses and bilateral control architecture provide gait kinematics that reproduce healthy gait kinematics to a greater extent than the subject’s daily-use passive prostheses. PMID:25014950

Virtual Constraint Control of a Powered Prosthetic Leg: From Simulation to Experiments with Transfemoral Amputees

PubMed Central

Lenzi, Tommaso; Hargrove, Levi J.; Sensinger, Jonathon W.

2014-01-01

Recent powered (or robotic) prosthetic legs independently control different joints and time periods of the gait cycle, resulting in control parameters and switching rules that can be difficult to tune by clinicians. This challenge might be addressed by a unifying control model used by recent bipedal robots, in which virtual constraints define joint patterns as functions of a monotonic variable that continuously represents the gait cycle phase. In the first application of virtual constraints to amputee locomotion, this paper derives exact and approximate control laws for a partial feedback linearization to enforce virtual constraints on a prosthetic leg. We then encode a human-inspired invariance property called effective shape into virtual constraints for the stance period. After simulating the robustness of the partial feedback linearization to clinically meaningful conditions, we experimentally implement this control strategy on a powered transfemoral leg. We report the results of three amputee subjects walking overground and at variable cadences on a treadmill, demonstrating the clinical viability of this novel control approach. PMID:25558185

Effects of ladder parameters on asymmetric patterns of force exertion during below-knee amputees climbing ladders.

PubMed

Li, Weidong; Li, Shiqi; Fu, Yan; Chen, Jacon

2017-03-01

Different from walking, ladder climbing requires four-limb coordination and more energy exertion for below-knee amputees (BKAs). We hypothesized that functional deficiency of a disabled limb shall be compensated by the other three intact limbs, showing an asymmetry pattern among limbs. Hand and foot forces of six below-knee amputees and six able-bodied people were collected. Hand, foot and hand/foot sum force variances between groups (non-BKA, intact side and prosthetic side) were carefully examined. Our hypothesis was validated that there is asymmetry between prosthetic and intact side. Results further showed that the ipsilateral hand of the prosthetic leg is stronger than the hand on the intact side, compensating weakness of the prosthetic leg. Effects of ladder rung separations and ladder slant on asymmetric force distribution of BKAs were evaluated, indicating that rung separation has a more significant interactive effect on hand/foot force of BKAs than ladder slant.

Quantifying prosthetic gait deviation using simple outcome measures

PubMed Central

Kark, Lauren; Odell, Ross; McIntosh, Andrew S; Simmons, Anne

2016-01-01

AIM: To develop a subset of simple outcome measures to quantify prosthetic gait deviation without needing three-dimensional gait analysis (3DGA). METHODS: Eight unilateral, transfemoral amputees and 12 unilateral, transtibial amputees were recruited. Twenty-eight able-bodied controls were recruited. All participants underwent 3DGA, the timed-up-and-go test and the six-minute walk test (6MWT). The lower-limb amputees also completed the Prosthesis Evaluation Questionnaire. Results from 3DGA were summarised using the gait deviation index (GDI), which was subsequently regressed, using stepwise regression, against the other measures. RESULTS: Step-length (SL), self-selected walking speed (SSWS) and the distance walked during the 6MWT (6MWD) were significantly correlated with GDI. The 6MWD was the strongest, single predictor of the GDI, followed by SL and SSWS. The predictive ability of the regression equations were improved following inclusion of self-report data related to mobility and prosthetic utility. CONCLUSION: This study offers a practicable alternative to quantifying kinematic deviation without the need to conduct complete 3DGA. PMID:27335814

Quadriceps muscle injury in trans-femoral amputees.

PubMed

Alsindi, Z; Datta, D

1998-12-01

Two male trans-femoral amputees using modular trans-femoral prostheses lost control and fell to the ground when their prosthetic knees gave way. The semi-automatic knee lock malfunctioned in the first case while the free knee stabilising mechanics gave way in the second case. This resulted in a high tensile force acting on the contralateral quadriceps muscle causing it to rupture. As there are a significant number of patients with both kinds of prostheses it is important to be aware of this possibility so that necessary actions can be taken to minimise its occurrence. Even with the currently available weight activated stance phase control, the prosthetic knee will give way if the knee is flexed more than 20 degrees on weight bearing. Good power and control of hip extensors on the amputation side is needed to control the prosthetic knee joint, especially in the early stage of the walking cycle, i.e., from heel strike to mid-stance. Quadriceps muscle injury in amputees, as far as the authors are aware, has not been reported previously.

The Development of a Myoelectric Training Tool for Above-Elbow Amputees

PubMed Central

Dawson, Michael R; Fahimi, Farbod; Carey, Jason P

2012-01-01

The objective of above-elbow myoelectric prostheses is to reestablish the functionality of missing limbs and increase the quality of life of amputees. By using electromyography (EMG) electrodes attached to the surface of the skin, amputees are able to control motors in myoelectric prostheses by voluntarily contracting the muscles of their residual limb. This work describes the development of an inexpensive myoelectric training tool (MTT) designed to help upper limb amputees learn how to use myoelectric technology in advance of receiving their actual myoelectric prosthesis. The training tool consists of a physical and simulated robotic arm, signal acquisition hardware, controller software, and a graphical user interface. The MTT improves over earlier training systems by allowing a targeted muscle reinnervation (TMR) patient to control up to two degrees of freedom simultaneously. The training tool has also been designed to function as a research prototype for novel myoelectric controllers. A preliminary experiment was performed in order to evaluate the effectiveness of the MTT as a learning tool and to identify any issues with the system. Five able-bodied participants performed a motor-learning task using the EMG controlled robotic arm with the goal of moving five balls from one box to another as quickly as possible. The results indicate that the subjects improved their skill in myoelectric control over the course of the trials. A usability survey was administered to the subjects after their trials. Results from the survey showed that the shoulder degree of freedom was the most difficult to control. PMID:22383905

The development of a myoelectric training tool for above-elbow amputees.

PubMed

Dawson, Michael R; Fahimi, Farbod; Carey, Jason P

2012-01-01

The objective of above-elbow myoelectric prostheses is to reestablish the functionality of missing limbs and increase the quality of life of amputees. By using electromyography (EMG) electrodes attached to the surface of the skin, amputees are able to control motors in myoelectric prostheses by voluntarily contracting the muscles of their residual limb. This work describes the development of an inexpensive myoelectric training tool (MTT) designed to help upper limb amputees learn how to use myoelectric technology in advance of receiving their actual myoelectric prosthesis. The training tool consists of a physical and simulated robotic arm, signal acquisition hardware, controller software, and a graphical user interface. The MTT improves over earlier training systems by allowing a targeted muscle reinnervation (TMR) patient to control up to two degrees of freedom simultaneously. The training tool has also been designed to function as a research prototype for novel myoelectric controllers. A preliminary experiment was performed in order to evaluate the effectiveness of the MTT as a learning tool and to identify any issues with the system. Five able-bodied participants performed a motor-learning task using the EMG controlled robotic arm with the goal of moving five balls from one box to another as quickly as possible. The results indicate that the subjects improved their skill in myoelectric control over the course of the trials. A usability survey was administered to the subjects after their trials. Results from the survey showed that the shoulder degree of freedom was the most difficult to control.

Compensatory changes accompanying chronic forced use of the nondominant hand by unilateral amputees.

PubMed

Philip, Benjamin A; Frey, Scott H

2014-03-05

Amputation of the dominant hand forces patients to use the nondominant hand exclusively, including for tasks (e.g., writing and drawing) that were formerly the sole domain of the dominant hand. The behavioral and neurological effects of this chronic forced use of the nondominant hand remain largely unknown. Yet, these effects may shed light on the potential to compensate for degradation or loss of dominant hand function, as well as the mechanisms that support motor learning under conditions of very long-term training. We used a novel precision drawing task and fMRI to investigate 8 adult human amputees with chronic (mean 33 years) unilateral dominant (right) hand absence, and right-handed matched controls (8 for fMRI, 19 for behavior). Amputees' precision drawing performances with their left hands reached levels of smoothness (associated with left hemisphere control), acceleration time (associated with right hemisphere control), and speed equivalent to controls' right hands, whereas accuracy maintained a level comparable with controls' left hands. This compensation is supported by an experience-dependent shift from heavy reliance on the dorsodorsal parietofrontal pathway (feedback control) to the ventrodorsal pathway and prefrontal regions involved in the cognitive control of goal-directed actions. Relative to controls, amputees also showed increased activity within the former cortical sensorimotor hand territory in the left (ipsilateral) hemisphere. These data demonstrate that, with chronic and exclusive forced use, the speed and quality of nondominant hand precision endpoint control in drawing can achieve levels nearly comparable with the dominant hand.

Fall Detection in Individuals With Lower Limb Amputations Using Mobile Phones: Machine Learning Enhances Robustness for Real-World Applications.

PubMed

Shawen, Nicholas; Lonini, Luca; Mummidisetty, Chaithanya Krishna; Shparii, Ilona; Albert, Mark V; Kording, Konrad; Jayaraman, Arun

2017-10-11

Automatically detecting falls with mobile phones provides an opportunity for rapid response to injuries and better knowledge of what precipitated the fall and its consequences. This is beneficial for populations that are prone to falling, such as people with lower limb amputations. Prior studies have focused on fall detection in able-bodied individuals using data from a laboratory setting. Such approaches may provide a limited ability to detect falls in amputees and in real-world scenarios. The aim was to develop a classifier that uses data from able-bodied individuals to detect falls in individuals with a lower limb amputation, while they freely carry the mobile phone in different locations and during free-living. We obtained 861 simulated indoor and outdoor falls from 10 young control (non-amputee) individuals and 6 individuals with a lower limb amputation. In addition, we recorded a broad database of activities of daily living, including data from three participants' free-living routines. Sensor readings (accelerometer and gyroscope) from a mobile phone were recorded as participants freely carried it in three common locations-on the waist, in a pocket, and in the hand. A set of 40 features were computed from the sensors data and four classifiers were trained and combined through stacking to detect falls. We compared the performance of two population-specific models, trained and tested on either able-bodied or amputee participants, with that of a model trained on able-bodied participants and tested on amputees. A simple threshold-based classifier was used to benchmark our machine-learning classifier. The accuracy of fall detection in amputees for a model trained on control individuals (sensitivity: mean 0.989, 1.96*standard error of the mean [SEM] 0.017; specificity: mean 0.968, SEM 0.025) was not statistically different (P=.69) from that of a model trained on the amputee population (sensitivity: mean 0.984, SEM 0.016; specificity: mean 0.965, SEM 0.022). Detection of falls in control individuals yielded similar results (sensitivity: mean 0.979, SEM 0.022; specificity: mean 0.991, SEM 0.012). A mean 2.2 (SD 1.7) false alarms per day were obtained when evaluating the model (vs mean 122.1, SD 166.1 based on thresholds) on data recorded as participants carried the phone during their daily routine for two or more days. Machine-learning classifiers outperformed the threshold-based one (P<.001). A mobile phone-based fall detection model can use data from non-amputee individuals to detect falls in individuals walking with a prosthesis. We successfully detected falls when the mobile phone was carried across multiple locations and without a predetermined orientation. Furthermore, the number of false alarms yielded by the model over a longer period of time was reasonably low. This moves the application of mobile phone-based fall detection systems closer to a real-world use case scenario. ©Nicholas Shawen, Luca Lonini, Chaithanya Krishna Mummidisetty, Ilona Shparii, Mark V Albert, Konrad Kording, Arun Jayaraman. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 11.10.2017.

[Comparative study of the volume difference vs. healthy limb, morphological and population description in transfemoral amputees].

PubMed

Mendoza-Cruz, Felipe; Rodríguez-Reyes, Gerardo; Galván Duque-Gastélum, Carlos; Alvarez-Camacho, Michelín

2014-07-01

Knowledge of the general characteristics and physical condition that keeps the transfemoral amputation stump to select and adapt appropriate type of prosthesis to restore a walking pattern amputee patient acceptable and useful design parameters set to propose new prosthetic systems. In this paper, the degree of difference between the volumes of the limb stump and healthy as well as morphological features occurred more frequently in the stumps of transfemoral amputees who were treated at the Laboratory of Orthotics and Prosthetics (LOP), Instituto Nacional de Rehabilitación (INR) in 2008. It captured all patients with unilateral transfemoral amputation left and right, over 18 years old, both sexes, use of hearing candidates were evaluated clinically and took three measurements of the circumferences at different wavelengths and the limb stump healthy, were calculated volumes of both sides using the mathematical model of the truncated cone and analyzed in three groups according to the level of amputation (proximal, middle and distal third). We obtained 49 patients, 39 men and 10 women, the difference stump volume compared to healthy limb volume per group were: 44.9% proximal third, middle third and distal 26.5%, 21.1%, the frequency of diagnostic data showed a stump right transfemoral amputees, due to metabolic, without use of prostheses, the most common morphological features indicate that the stump has a conical shape and size distal third, whose tissue is semi-flaccid consistency, the scar is not adhered to deep planes and shows a negative tinel, the mattress soft tissue is 2.15 ± 1.3 cm and physically presents a force level 4 in the clinical rating scale Daniels. The data are consistent with other studies comparing the percentage of the volume change with the percentages of reduced diameters transfemoral stump muscle, likewise agrees most amputees incidence of diabetes mellitus with other studies, cataloging it eat first cause amputation. The general description developed transfemoral stump-served in the INR will help in the process of manufacture of prostheses and prosthetic design new systems that you attend these needs.

Association between amputation, arthritis and osteopenia in British male war veterans with major lower limb amputations.

PubMed

Kulkarni, J; Adams, J; Thomas, E; Silman, A

1998-08-01

To investigate the association between amputation, osteoarthritis and osteopenia in male war veterans with major lower limb amputations. Specific questions were to determine whether lower limb amputees following trauma are at subsequent risk of developing osteoarthritis (OA) and osteoporosis of the hip on both the amputated and nonamputated sides. Retrospective cohort study in British Male Second World War veterans with major unilateral lower limb amputations. Seventy-five male Second World War veterans with major lower limb amputations known to be alive were invited to participate from a subregional rehabilitation centre. After exclusions, 44 agreed to attend for examination and radiological screening. The presence of hip OA was determined from a single anterior posterior pelvic X-ray using two approaches: minimum joint space and the Kellgren and Lawrence (K&L) scoring system. Bone mineral density (BMD) was measured by a dual energy X-ray absorptiometry (DXA) scan and prosthetic rehabilitation outcome measures were recorded. Twenty-seven (61%) hips on the amputated side and 10 (23%) on the nonamputated side were positive for OA (based on Kellgren and Lawrence grade of >2). Using a minimum joint space threshold of below 2.5 mm, 24 (55%) hips on the amputation side and 8 (18%) on the nonamputated side were also positive for OA. There was a threefold increased risk of OA for those with above-knee compared to a below-knee amputation. By contrast, from published general population surveys only 4 (11%) cases of hip OA would have been expected on both the amputated and nonamputated hips. There was a significant decrease in femoral neck BMD in the amputated side (p <0.0001) and significantly lower BMD in above-knee amputees than in below-knee amputees (p = 0.0027) as compared to normal age- and sex-matched population. Male war veterans with unilateral major lower limb amputations develop significantly more osteoarthritis of the hip than expected on both ipsi- and contralateral sides. Amputation was also associated with loss of bone density. Above-knee amputees develop significantly more hip osteoarthritis and osteopenia of greater severity in the amputated side than below-knee amputees.

A comparison of the real-time controllability of pattern recognition to conventional myoelectric control for discrete and simultaneous movements

PubMed Central

2014-01-01

Myoelectric control has been used for decades to control powered upper limb prostheses. Conventional, amplitude-based control has been employed to control a single prosthesis degree of freedom (DOF) such as closing and opening of the hand. Within the last decade, new and advanced arm and hand prostheses have been constructed that are capable of actuating numerous DOFs. Pattern recognition control has been proposed to control a greater number of DOFs than conventional control, but has traditionally been limited to sequentially controlling DOFs one at a time. However, able-bodied individuals use multiple DOFs simultaneously, and it may be beneficial to provide amputees the ability to perform simultaneous movements. In this study, four amputees who had undergone targeted motor reinnervation (TMR) surgery with previous training using myoelectric prostheses were configured to use three control strategies: 1) conventional amplitude-based myoelectric control, 2) sequential (one-DOF) pattern recognition control, 3) simultaneous pattern recognition control. Simultaneous pattern recognition was enabled by having amputees train each simultaneous movement as a separate motion class. For tasks that required control over just one DOF, sequential pattern recognition based control performed the best with the lowest average completion times, completion rates and length error. For tasks that required control over 2 DOFs, the simultaneous pattern recognition controller performed the best with the lowest average completion times, completion rates and length error compared to the other control strategies. In the two strategies in which users could employ simultaneous movements (conventional and simultaneous pattern recognition), amputees chose to use simultaneous movements 78% of the time with simultaneous pattern recognition and 64% of the time with conventional control for tasks that required two DOF motions to reach the target. These results suggest that when amputees are given the ability to control multiple DOFs simultaneously, they choose to perform tasks that utilize multiple DOFs with simultaneous movements. Additionally, they were able to perform these tasks with higher performance (faster speed, lower length error and higher completion rates) without losing substantial performance in 1 DOF tasks. PMID:24410948

Developing Non-Somatotopic Phantom Finger Sensation to Comparable Levels of Somatotopic Sensation through User Training With Electrotactile Stimulation.

PubMed

Chai, Guohong; Zhang, Dingguo; Zhu, Xiangyang

2017-05-01

Cutaneous electrical stimulation can provide tactile feedback for upper-limb amputees through somatotopic feedback (SF) or non-somatotopic feedback (NF). The SF delivers electrotactile stimulus to projection finger maps (PFMs) on the stumps of amputees, which outperforms NF that transfers stimulus to other human intact skin areas in general. However, the SF areas on stumps are very limited and often occupied by electromyography (EMG) sensors in application of myoelectric prosthesis. This work aims at improving NF performance on human upper arms through user training with electrotactile stimulation. The experiments were conducted over seven consecutive days on nine able-bodied subjects and two forearm amputees. The performance measures of NF/SF included the correct identification rates (CIR s ), the response time and the NASA-TLX questionnaire. The between-day CIR s on NF sites increased logarithmically with a mean course of 3-day rapid-improving phase and plateaued in the relative-steady phase. The response time and NASA-TLX scores could also rapidly reduce to the comparable levels of the SF areas during the same mean period of 3-day rapid-improving phase, respectively. These results indicated that the performance of NF could be highly improved to the equivalent level as that of SF through 3-day electrotactile training, which we named as "3-day effect". It provides important insights that intact skin areas without phantom sensations can effectively replace SF sites to transfer tactile feedback after continuous user training, which validates effectiveness of non-invasive interfaces of tactile feedback for upper-limb amputees in practice.

Assessing the Relative Contributions of Active Ankle and Knee Assistance to the Walking Mechanics of Transfemoral Amputees Using a Powered Prosthesis

PubMed Central

Simon, Ann M.; Hargrove, Levi J.

2016-01-01

Powered knee-ankle prostheses are capable of providing net-positive mechanical energy to amputees. Yet, there are limitless ways to deliver this energy throughout the gait cycle. It remains largely unknown how different combinations of active knee and ankle assistance affect the walking mechanics of transfemoral amputees. This study assessed the relative contributions of stance phase knee swing initiation, increasing ankle stiffness and powered plantarflexion as three unilateral transfemoral amputees walked overground at their self-selected walking speed. Five combinations of knee and ankle conditions were evaluated regarding the kinematics and kinetics of the amputated and intact legs using repeated measures analyses of variance. We found eliminating active knee swing initiation or powered plantarflexion was linked to increased compensations of the ipsilateral hip joint during the subsequent swing phase. The elimination of knee swing initiation or powered plantarflexion also led to reduced braking ground reaction forces of the amputated and intact legs, and influenced both sagittal and frontal plane loading of the intact knee joint. Gradually increasing prosthetic ankle stiffness influenced the shape of the prosthetic ankle plantarflexion moment, more closely mirroring the intact ankle moment. Increasing ankle stiffness also corresponded to increased prosthetic ankle power generation (despite a similar maximum stiffness value across conditions) and increased braking ground reaction forces of the amputated leg. These findings further our understanding of how to deliver assistance with powered knee-ankle prostheses and the compensations that occur when specific aspects of assistance are added/removed. PMID:26807889

Epidemiologic data of trauma-related lower limb amputees: A single center 10-year experience.

PubMed

Yaşar, Evren; Tok, Fatih; Kesikburun, Serdar; Ada, A Mustafa; Kelle, Bayram; Göktepe, A Salim; Yazıcıoğlu, Kamil; Tan, A Kenan

2017-02-01

The aim of this study is three fold: 1) to introduce epidemiologic data of patients with trauma-related amputations as a 10-year experience of a rehabitation center; 2) to determine comorbidities and secondary conditions of lower limb loss; 3) to determine the rehospitalization reasons for lower limb amputee patients. This retrospective study was conducted in a tertiary rehabilitation center in Turkey. Clinical and demographic data of amputees including sex, age, employment status, time since amputation, time after amputation to first hospitalization, length of hospitalization, how many times the patient was hospitalized, reason for hospitalization, stump complications, comorbid conditions, amputation level and K classifacation were documented. Three hundred ninetynine patients with a mean age of 23,48±6,04 (4-74) years were included in this study. Mean duration after amputation was 119,71±68,86months. Patients were 3,43±2,53 times hospitalized. Landmine explosion was the most common etiology of amputation with 370 patients (92.7%). Below knee amputation was the most common amputation level with 230 (50,77%) amputations. 399 patients were hospitalized 1369 times and the most common hospitalization reason were stump complications (356 times, 26,00%). Spur formation (202 times) was the most common stump complications. Pyscologic disorders were the most common comorbidity with 68 patient (37,56%). Patients with traumatic limb amputations are likely to experience several complications and comorbidities. Prevention of secondary conditions affecting those living with the loss of a limb is an important part of amputee rehabilitation and may prevent rehospitalization. Copyright © 2016 Elsevier Ltd. All rights reserved.

Referral of sensation to an advanced humanoid robotic hand prosthesis.

PubMed

Rosén, Birgitta; Ehrsson, H Henrik; Antfolk, Christian; Cipriani, Christian; Sebelius, Fredrik; Lundborg, Göran

2009-01-01

Hand prostheses that are currently available on the market are used by amputees to only a limited extent, partly because of lack of sensory feedback from the artificial hand. We report a pilot study that showed how amputees can experience a robot-like advanced hand prosthesis as part of their own body. We induced a perceptual illusion by which touch applied to the stump of the arm was experienced from the artificial hand. This illusion was elicited by applying synchronous tactile stimulation to the hidden amputation stump and the robotic hand prosthesis in full view. In five people who had had upper limb amputations this stimulation caused referral touch sensation from the stump to the artificial hand, and the prosthesis was experienced more like a real hand. We also showed that this illusion can work when the amputee controls the movements of the artificial hand by recordings of the arm muscle activity with electromyograms. These observations indicate that the previously described "rubber hand illusion" is also valid for an advanced hand prosthesis, even when it has a robotic-like appearance.

Two-dimensional myoelectric control of a robotic arm for upper limb amputees

NASA Astrophysics Data System (ADS)

López Celani, Natalia M.; Soria, Carlos M.; Orosco, Eugenio C.; di Sciascio, Fernando A.; Valentinuzzi, Max E.

2007-11-01

Rehabilitation engineering and medicine have become integral and significant parts of health care services, particularly and unfortunately in the last three or four decades, because of wars, terrorism and large number of car accidents. Amputees show a high rate of rejection to wear prosthetic devices, often because of lack of an adequate period of adaptation. A robotic arm may appear as a good preliminary stage. To test the hypothesis, myoelectric signals from two upper limb amputees and from four normal volunteers were fed, via adequate electronic conditioning and using MATLAB, to an industrial robotic arm. Proportional strength control was used for two degrees of freedom (x-y plane) by means of eight signal features of control (four traditional statistics plus energy, integral of the absolute value, Willison's amplitude, waveform length and envelope) for comparison purposes, and selecting the best of them as final reference. Patients easily accepted the system and learned in short time how to operate it. Results were encouraging so that valuable training, before prosthesis is implanted, appears as good feedback; besides, these patients can be hired as specialized operators in semi-automatized industry.

Somatic and movement inductions phantom limb in non-amputees

NASA Astrophysics Data System (ADS)

Casas, D. M.; Gentiletti, G. G.; Braidot, A. A.

2016-04-01

The illusion of the mirror box is a tool for phantom limb pain treatment; this article proposes the induction of phantom limb syndrome on non-amputees upper limb, with a neurological trick of the mirror box. With two study situations: a) Somatic Induction is a test of the literature reports qualitatively, and novel proposal b) Motor Induction, which is an objective report by recording surface EEG. There are 3 cases proposed for Motor illusion, for which grasped movement is used: 1) Control: movement is made, 2) illusion: the mirror box is used, and 3) Imagination: no movement is executed; the subject only imagines its execution. Three different tasks are registered for each one of them (left hand, right hand, and both of them). In 64% of the subjects for somatic experience, a clear response to the illusion was observed. In the experience of motor illusion, cortical activation is detected in both hemispheres of the primary motor cortex during the illusion, where the hidden hand remains motionless. These preliminary findings in phantom limb on non-amputees can be a tool for neuro-rehabilitation and neuro-prosthesis control training.

Limb Position Tolerant Pattern Recognition for Myoelectric Prosthesis Control with Adaptive Sparse Representations From Extreme Learning.

PubMed

Betthauser, Joseph L; Hunt, Christopher L; Osborn, Luke E; Masters, Matthew R; Levay, Gyorgy; Kaliki, Rahul R; Thakor, Nitish V

2018-04-01

Myoelectric signals can be used to predict the intended movements of an amputee for prosthesis control. However, untrained effects like limb position changes influence myoelectric signal characteristics, hindering the ability of pattern recognition algorithms to discriminate among motion classes. Despite frequent and long training sessions, these deleterious conditional influences may result in poor performance and device abandonment. We present a robust sparsity-based adaptive classification method that is significantly less sensitive to signal deviations resulting from untrained conditions. We compare this approach in the offline and online contexts of untrained upper-limb positions for amputee and able-bodied subjects to demonstrate its robustness compared against other myoelectric classification methods. We report significant performance improvements () in untrained limb positions across all subject groups. The robustness of our suggested approach helps to ensure better untrained condition performance from fewer training conditions. This method of prosthesis control has the potential to deliver real-world clinical benefits to amputees: better condition-tolerant performance, reduced training burden in terms of frequency and duration, and increased adoption of myoelectric prostheses.

Functional Assessment of the Vanderbilt Multigrasp Myoelectric Hand: A Continuing Case Study

PubMed Central

Dalley, Skyler A.; Bennett, Daniel A.; Goldfarb, Michael

2015-01-01

This paper presents a case study involving the functional assessment of the Vanderbilt Multigrasp (VMG) hand prosthesis on a single transradial amputee subject. In particular, a transradial amputee subject performed the Southampton Hand Assessment Procedure (SHAP) using the hand prosthesis and multigrasp myoelectric controller in a series of experimental sessions occurring over a multi-week time span. The subject’s index of function (IoF) improved with each session, although essentially plateaued after the fourth session, resulting in a IoF score of 87, which compares favorably to SHAP scores published in previous studies. PMID:25571412

Impact on the biomechanics of overground gait of using an 'Echelon' hydraulic ankle-foot device in unilateral trans-tibial and trans-femoral amputees.

PubMed

De Asha, Alan R; Munjal, Ramesh; Kulkarni, Jai; Buckley, John G

2014-08-01

If a prosthetic foot creates resistance to forwards shank rotation as it deforms during loading, it will exert a braking effect on centre of mass progression. The present study determines whether the centre of mass braking effect exerted by an amputee's habitual rigid 'ankle' foot was reduced when they switched to using an 'Echelon' hydraulic ankle-foot device. Nineteen lower limb amputees (eight trans-femoral, eleven trans-tibial) walked overground using their habitual dynamic-response foot with rigid 'ankle' or 'Echelon' hydraulic ankle-foot device. Analysis determined changes in how the centre of mass was transferred onto and above the prosthetic-foot, freely chosen walking speed, and spatio-temporal parameters of gait. When using the hydraulic device both groups had a smoother/more rapid progression of the centre of pressure beneath the prosthetic hindfoot (p≤0.001), and a smaller reduction in centre of mass velocity during prosthetic-stance (p<0.001). As a result freely chosen walking speed was higher in both groups when using the device (p≤0.005). In both groups stance and swing times and cadence were unaffected by foot condition whereas step length tended (p<0.07) to increase bilaterally when using the hydraulic device. Effect size differences between foot types were comparable across groups. Use of a hydraulic ankle-foot device reduced the foot's braking effect for both amputee groups. Findings suggest that attenuation of the braking effect from the foot in early stance may be more important to prosthetic-foot function than its ability to return energy in late stance. Copyright © 2014. Published by Elsevier Ltd.

The Effect of Prosthetic Foot Push-off on Mechanical Loading Associated with Knee Osteoarthritis in Lower Extremity Amputees

PubMed Central

Morgenroth, David C.; Segal, Ava D.; Zelik, Karl E.; Czerniecki, Joseph M.; Klute, Glenn K.; Adamczyk, Peter G.; Orendurff, Michael S.; Hahn, Michael E.; Collins, Steven H.; Kuo, Art D.

2011-01-01

Lower extremity amputation not only limits mobility, but also increases the risk of knee osteoarthritis of the intact limb. Dynamic walking models of non-amputees suggest that pushing-off from the trailing limb can reduce collision forces on the leading limb. These collision forces may determine the peak knee external adduction moment (EAM), which has been linked to the development of knee OA in the general population. We therefore hypothesized that greater prosthetic push-off would lead to reduced loading and knee EAM of the intact limb in unilateral transtibial amputees. Seven unilateral transtibial amputees were studied during gait under three prosthetic foot conditions that were intended to vary push-off. Prosthetic foot-ankle push-off work, intact limb knee EAM and ground reaction impulses for both limbs during step-to-step transition were measured. Overall, trailing limb prosthetic push-off work was negatively correlated with leading intact limb 1st peak knee EAM (slope = −0.72 +/− 0.22; p=0.011). Prosthetic push-off work and 1st peak intact knee EAM varied significantly with foot type. The prosthetic foot condition with the least push-off demonstrated the largest knee EAM, which was reduced by 26% with the prosthetic foot producing the most push-off. Trailing prosthetic limb push-off impulse was negatively correlated with leading intact limb loading impulse (slope = −0.34 +/− 0.14; p=.001), which may help explain how prosthetic limb push-off can affect intact limb loading. Prosthetic feet that perform more prosthetic push-off appear to be associated with a reduction in 1st peak intact knee EAM, and their use could potentially reduce the risk and burden of knee osteoarthritis in this population. PMID:21803584

The effect of prosthetic foot push-off on mechanical loading associated with knee osteoarthritis in lower extremity amputees.

PubMed

Morgenroth, David C; Segal, Ava D; Zelik, Karl E; Czerniecki, Joseph M; Klute, Glenn K; Adamczyk, Peter G; Orendurff, Michael S; Hahn, Michael E; Collins, Steven H; Kuo, Art D

2011-10-01

Lower extremity amputation not only limits mobility, but also increases the risk of knee osteoarthritis of the intact limb. Dynamic walking models of non-amputees suggest that pushing-off from the trailing limb can reduce collision forces on the leading limb. These collision forces may determine the peak knee external adduction moment (EAM), which has been linked to the development of knee OA in the general population. We therefore hypothesized that greater prosthetic push-off would lead to reduced loading and knee EAM of the intact limb in unilateral transtibial amputees. Seven unilateral transtibial amputees were studied during gait under three prosthetic foot conditions that were intended to vary push-off. Prosthetic foot-ankle push-off work, intact limb knee EAM and ground reaction impulses for both limbs during step-to-step transition were measured. Overall, trailing limb prosthetic push-off work was negatively correlated with leading intact limb 1st peak knee EAM (slope=-.72±.22; p=.011). Prosthetic push-off work and 1st peak intact knee EAM varied significantly with foot type. The prosthetic foot condition with the least push-off demonstrated the largest knee EAM, which was reduced by 26% with the prosthetic foot producing the most push-off. Trailing prosthetic limb push-off impulse was negatively correlated with leading intact limb loading impulse (slope=-.34±.14; p=.001), which may help explain how prosthetic limb push-off can affect intact limb loading. Prosthetic feet that perform more prosthetic push-off appear to be associated with a reduction in 1st peak intact knee EAM, and their use could potentially reduce the risk and burden of knee osteoarthritis in this population. Published by Elsevier B.V.

Sprint Start Kinetics of Amputee and Non-Amputee Sprinters

PubMed Central

Willwacher, Steffen; Herrmann, Volker; Heinrich, Kai; Funken, Johannes; Strutzenberger, Gerda; Goldmann, Jan-Peter; Braunstein, Björn; Brazil, Adam; Irwin, Gareth; Potthast, Wolfgang; Brüggemann, Gert-Peter

2016-01-01

The purpose of this study was to explore the relationship between the forces applied to the starting blocks and the start performances (SPs) of amputee sprinters (ASs) and non-amputee sprinters (NASs). SPs of 154 male and female NASs (100-m personal records [PRs], 9.58–14.00 s) and 7 male ASs (3 unilateral above knee, 3 unilateral below knee, 1 bilateral below knee; 100 m PRs, 11.70–12.70 s) with running specific prostheses (RSPs) were analysed during full-effort sprint starts using instrumented starting blocks that measured the applied forces in 3D. Using the NAS dataset and a combination of factor analysis and multiple regression techniques, we explored the relationship between force characteristics and SP (quantified by normalized average horizontal block power). Start kinetics were subsequently compared between ASs and NASs who were matched based on their absolute 100 m PR and their 100 m PR relative to the world record in their starting class. In NASs, 86% of the variance in SP was shared with five latent factors on which measured parameters related to force application to the rear and front blocks and the respective push-off directions in the sagittal plane of motion were loaded. Mediolateral force application had little influence on SP. The SP of ASs was significantly reduced compared to that of NASs matched on the basis of relative 100-m PR (−33.8%; d = 2.11, p < 0.001), while a non-significant performance reduction was observed when absolute 100-m PRs were used (−17.7%; d = 0.79, p = 0.09). These results are at least partially explained by the fact that force application to the rear block was clearly impaired in the affected legs of ASs. PMID:27846241

A sleeping phantom leg awakened following hemicolectomy, thrombosis, and chemotherapy: a case report.

PubMed

Giummarra, Melita J; Bradshaw, John L; Nicholls, Michael Er; Georgiou-Karistianis, Nellie; Gibson, Stephen J

2011-05-25

We describe the case of a patient who experienced phantom pain that began 42 years after right above-the-knee amputation. Immediately prior to phantom pain onset, this long-term amputee had experienced, in rapid succession, cancer, hemicolectomy, chemotherapy, and thrombotic occlusion. Very little has been published to date on the association between chemotherapy and exacerbation of neuropathic pain in amputees, let alone the phenomenon of bringing about pain in amputees who have been pain-free for many decades. While this patient presented with a unique profile following a rare sequence of medical events, his case should be recognized considering the frequent co-occurrence of osteomyelitis, chemotherapy, and amputation. A 68-year-old Australian Caucasian man presented 42 years after right above-the-knee amputation with phantom pain immediately following hemicolectomy, thrombotic occlusion in the amputated leg, and chemotherapy treatment with leucovorin and 5-fluorouracil. He exhibited probable hyperalgesia with a reduced pinprick threshold and increased stump sensitivity, indicating likely peripheral and central sensitization. Our patient, who had long-term nerve injury due to amputation, together with recent ischemic nerve and tissue injury due to thrombosis, exhibited likely chemotherapy-induced neuropathy. While he presented with unique treatment needs, cases such as this one may actually be quite common considering that osteosarcoma can frequently lead to amputation and be followed by chemotherapy. The increased susceptibility of amputees to developing potentially intractable chemotherapy-induced neuropathic pain should be taken into consideration throughout the course of chemotherapy treatment. Patients in whom chronic phantom pain then develops, perhaps together with mobility issues, inevitably place greater demands on healthcare service providers that require treatment by various clinical specialists, including oncologists, neurologists, prosthetists, and, most frequently, general practitioners.

Cross-cultural validation of the Prosthesis Evaluation Questionnaire in vascular amputees fitted with prostheses in Spain.

PubMed

Benavent, Jose Vicente; Igual, Celedonia; Mora, Enrique; Antonio, Rosa; Tenias, Jose Maria

2016-12-01

The lack of specific prosthetic-related outcome instruments for Spanish amputees must be addressed. To elaborate a culturally equivalent version of the Prosthesis Evaluation Questionnaire in the Spanish language. Cross-cultural questionnaire validation. Two-step process for cultural adaptation: forward and backward translations of English original and Spanish translated versions; assessment of both construct and criterion validity and reliability in a group of vascular amputees. A total of 61 patients were recruited, 44 men (72.1%) and 17 women (27.9%), with a median age of 71.1 years (standard deviation: 7.7 years; range: 51-87 years). In the Prosthesis Evaluation Questionnaire-Spanish, the lowest scores were for gait and frustration, and the highest scores were for noise and stump health. Internal consistency of the questionnaire was acceptable (>0.70) for four of the scales used in the Prosthesis Evaluation Questionnaire but poor (<0.50) for the scales relating to appearance and stump health. Correlations with the quality-of-life levels as measured by the Short Form-36 were positive and mostly significant. Prosthesis Evaluation Questionnaire-Spanish could assess the quality of life in patients who have undergone vascular amputations and then been fitted with a prosthetic limb. The questionnaire shows adequate criteria validity when compared with other instruments for measuring quality of life. The Prosthesis Evaluation Questionnaire-Spanish could be a valid and reliable instrument for assessing adaptation to prostheses in vascular amputees. The questionnaire adds information relevant to the patient and the physician and may identify cases with poor expected adaptation to the prosthesis. © The International Society for Prosthetics and Orthotics 2015.

Dating and intimate relationships of women with below-knee amputation: an exploratory study.

PubMed

Mathias, Zoë; Harcourt, Diana

2014-01-01

This study investigates experiences of dating and intimate relationships amongst women who use a below-knee prosthesis. Four women took part in semi-structured online interviews. Transcripts were subject to interpretative phenomenological analysis (IPA). Five themes were identified: Revealing and Exposing: Disclosing the Amputation and Prosthesis; Judging and Judged: Internal Fears and Self-Doubt; Trusting and Accepting: Good Guy/Bad Guy Elimination; Taking it Further: The Need for Depth; and Realisation: Accepting and Feeling Accepted. Participants described how, despite negative feelings towards their appearance and body image, they chose not to conceal their prosthesis when dating. Rather, it was used as a means of screening potential partners in their search for deep and meaningful relationships. Realising that others were not prejudiced towards people who use a prosthetic had helped them become more comfortable with their own prosthesis. These findings suggest that facilitating contact with other below-knee amputees and, in some cases specialist support, could help those who are struggling with the challenges they face regarding dating and intimate relationships. They also highlight the need for researchers and clinicians to give more attention to these important aspects of amputees' lives. Implications for Rehabilitation Amputation can have a significant psychosocial impact for those affected. The relative invisibility of below-knee amputation and prostheses can present particular challenges for amputees looking to establish romantic and intimate relationships, particularly around when and how to disclose the limb loss to potential partners. Developing a sense of resilience to the reactions of other people can help those who have undergone below-knee amputation. Support for people affected by below-knee amputation should routinely consider their needs and concerns in relation to new and established relationships, offer specialist psychosocial input when needed and provide opportunities for support from other amputees.

Use of and confidence in administering outcome measures among clinical prosthetists: Results from a national survey and mixed-methods training program.

PubMed

Gaunaurd, Ignacio; Spaulding, Susan E; Amtmann, Dagmar; Salem, Rana; Gailey, Robert; Morgan, Sara J; Hafner, Brian J

2015-08-01

Outcome measures can be used in prosthetic practices to evaluate interventions, inform decision making, monitor progress, document outcomes, and justify services. Strategies to enhance prosthetists' ability to use outcome measures are needed to facilitate their adoption in routine practice. To assess prosthetists' use of outcome measures and evaluate the effects of training on their confidence in administering performance-based measures. Cross-sectional and single-group pretest-posttest survey. Seventy-nine certified prosthetists (mean of 16.0 years of clinical experience) were surveyed about their experiences with 20 standardized outcome measures. Prosthetists were formally trained by the investigators to administer the Timed Up and Go and Amputee Mobility Predictor. Prosthetists' confidence in administering the Timed Up and Go and Amputee Mobility Predictor was measured before and after training. The majority of prosthetists (62%) were classified as non-routine outcome measure users. Confidence administering the Timed Up and Go and Amputee Mobility Predictor prior to training was low-to-moderate across the study sample. Training significantly (p < 0.0001) improved prosthetists' confidence in administering both instruments. Prosthetists in this study reported limited use of and confidence with standardized outcome measures. Interactive training resulted in a statistically significant increase of prosthetists' confidence in administering the Timed Up and Go and Amputee Mobility Predictor and may facilitate use of outcome measures in clinical practice. Frequency of outcome measure use in the care of persons with limb loss has not been studied. Study results suggest that prosthetists may not regularly use standardized outcome measures and report limited confidence in administering them. Training enhances confidence and may encourage use of outcome measures in clinical practice. © The International Society for Prosthetics and Orthotics 2014.

Feasibility testing of smart tablet questionnaires compared to paper questionnaires in an amputee rehabilitation clinic.

PubMed

Payne, Michael; Janzen, Shannon; Earl, Eric; Deathe, Barry; Viana, Ricardo

2017-08-01

Capturing the variability that exists among patients attending an amputee clinic using standardized paper-based questionnaires is time-consuming and may not be practical for routine clinical use. Electronic questionnaires are a potential solution; however, the benefits are dependent on the feasibility and acceptance of this mode of data collection among patients. To determine the feasibility and patient preference/comfort in using a tablet-based questionnaire for data collection in an outpatient amputee rehabilitation clinic compared to a traditional paper-based questionnaire. Observational study. In all, 48 patients with major extremity amputations completed both tablet and paper questionnaires related to their amputation and prosthetic use. Both trials were timed; patients then completed a semi-structured questionnaire about their experience. In all, 20.5% of patients needed hands-on assistance completing the paper questionnaire compared to 20.8% for the tablet. The majority of participants (52.1%) indicated a preference for the tablet questionnaire; 64.6% of patients felt the tablet collected a more complete and accurate representation of their status and needs. In all, 70.8% of participants described themselves as comfortable using the tablet. Despite comorbidities, patients with amputations demonstrated excellent acceptance of the electronic tablet-based questionnaire. Tablet questionnaires have significant potential advantages over paper questionnaires and should be further explored. Clinical relevance A custom electronic questionnaire was found to be beneficial for routine clinic use and was well received by patients in an amputee rehabilitation clinic. Development of such questionnaires can provide an efficient mechanism to collect meaningful data that can be used for individual patient care and program quality improvement initiatives.

Gait termination on a declined surface in trans-femoral amputees: Impact of using microprocessor-controlled limb system.

PubMed

Abdulhasan, Zahraa M; Scally, Andy J; Buckley, John G

2018-05-30

Walking down ramps is a demanding task for transfemoral-amputees and terminating gait on ramps is even more challenging because of the requirement to maintain a stable limb so that it can do the necessary negative mechanical work on the centre-of-mass in order to arrest (dissipate) forward/downward velocity. We determined how the use of a microprocessor-controlled limb system (simultaneous control over hydraulic resistances at ankle and knee) affected the negative mechanical work done by each limb when transfemoral-amputees terminated gait during ramp descent. Eight transfemoral-amputees completed planned gait terminations (stopping on prosthesis) on a 5-degree ramp from slow and customary walking speeds, with the limb's microprocessor active or inactive. When active the limb operated in its 'ramp-descent' mode and when inactive the knee and ankle devices functioned at constant default levels. Negative limb work, determined as the integral of the negative mechanical (external) limb power during the braking phase, was compared across speeds and microprocessor conditions. Negative work done by each limb increased with speed (p < 0.001), and on the prosthetic limb it was greater when the microprocessor was active compared to inactive (p = 0.004). There was no change in work done across microprocessor conditions on the intact limb (p = 0.35). Greater involvement of the prosthetic limb when the limb system was active indicates its ramp-descent mode effectively altered the hydraulic resistances at the ankle and knee. Findings highlight participants became more assured using their prosthetic limb to arrest centre-of-mass velocity. Copyright © 2018 Elsevier Ltd. All rights reserved.

Sprint Start Kinetics of Amputee and Non-Amputee Sprinters.

PubMed

Willwacher, Steffen; Herrmann, Volker; Heinrich, Kai; Funken, Johannes; Strutzenberger, Gerda; Goldmann, Jan-Peter; Braunstein, Björn; Brazil, Adam; Irwin, Gareth; Potthast, Wolfgang; Brüggemann, Gert-Peter

2016-01-01

The purpose of this study was to explore the relationship between the forces applied to the starting blocks and the start performances (SPs) of amputee sprinters (ASs) and non-amputee sprinters (NASs). SPs of 154 male and female NASs (100-m personal records [PRs], 9.58-14.00 s) and 7 male ASs (3 unilateral above knee, 3 unilateral below knee, 1 bilateral below knee; 100 m PRs, 11.70-12.70 s) with running specific prostheses (RSPs) were analysed during full-effort sprint starts using instrumented starting blocks that measured the applied forces in 3D. Using the NAS dataset and a combination of factor analysis and multiple regression techniques, we explored the relationship between force characteristics and SP (quantified by normalized average horizontal block power). Start kinetics were subsequently compared between ASs and NASs who were matched based on their absolute 100 m PR and their 100 m PR relative to the world record in their starting class. In NASs, 86% of the variance in SP was shared with five latent factors on which measured parameters related to force application to the rear and front blocks and the respective push-off directions in the sagittal plane of motion were loaded. Mediolateral force application had little influence on SP. The SP of ASs was significantly reduced compared to that of NASs matched on the basis of relative 100-m PR (-33.8%; d = 2.11, p < 0.001), while a non-significant performance reduction was observed when absolute 100-m PRs were used (-17.7%; d = 0.79, p = 0.09). These results are at least partially explained by the fact that force application to the rear block was clearly impaired in the affected legs of ASs.

Trans-tibial amputee gait: time-distance parameters and EMG activity.

PubMed

Isakov, E; Keren, O; Benjuya, N

2000-12-01

Gait analysis of trans-tibial (TT) amputees discloses asymmetries in gait parameters between the amputated and sound legs. The present study aimed at outlining differences between both legs with regard to kinematic parameters and activity of the muscles controlling the knees. The gait of 14 traumatic TT amputees, walking at a mean speed of 74.96 m/min, was analysed by means of an electronic walkway, video camera, and portable electromyography system. Results showed differences in kinematic parameters. Step length, step time and swing time were significantly longer, while stance time and single support time were significantly shorter on the amputated side. A significant difference was also found between knee angle in both legs at heel strike. The biceps femoris/vastus medialis ratio in the amputated leg, during the first half of stance phase, was significantly higher when compared to the same muscle ratio in the sound leg. This difference was due to the higher activity of the biceps femoris, almost four times higher than the vastus medialis in the amputated leg. The observed differences in time-distance parameters are due to stiffness of the prosthesis ankle (the SACH foot) that impedes the normal forward advance of the amputated leg during the first half of stance. The higher knee flexion at heel strike is due to the necessary socket alignment. Unlike in the sound leg, the biceps femoris in the amputated leg reaches maximal activity during the first half of stance, cocontracting with the vastus medialis, to support body weight on the amputated leg. The obtained data can serve as a future reference for evaluating the influence of new prosthetic components on the quality of TT amputee's gait.

Gait symmetry and regularity in transfemoral amputees assessed by trunk accelerations

PubMed Central

2010-01-01

Background The aim of this study was to evaluate a method based on a single accelerometer for the assessment of gait symmetry and regularity in subjects wearing lower limb prostheses. Methods Ten transfemoral amputees and ten healthy control subjects were studied. For the purpose of this study, subjects wore a triaxial accelerometer on their thorax, and foot insoles. Subjects were asked to walk straight ahead for 70 m at their natural speed, and at a lower and faster speed. Indices of step and stride regularity (Ad1 and Ad2, respectively) were obtained by the autocorrelation coefficients computed from the three acceleration components. Step and stride durations were calculated from the plantar pressure data and were used to compute two reference indices (SI1 and SI2) for step and stride regularity. Results Regression analysis showed that both Ad1 well correlates with SI1 (R2 up to 0.74), and Ad2 well correlates with SI2 (R2 up to 0.52). A ROC analysis showed that Ad1 and Ad2 has generally a good sensitivity and specificity in classifying amputee's walking trial, as having a normal or a pathologic step or stride regularity as defined by means of the reference indices SI1 and SI2. In particular, the antero-posterior component of Ad1 and the vertical component of Ad2 had a sensitivity of 90.6% and 87.2%, and a specificity of 92.3% and 81.8%, respectively. Conclusions The use of a simple accelerometer, whose components can be analyzed by the autocorrelation function method, is adequate for the assessment of gait symmetry and regularity in transfemoral amputees. PMID:20085653

[The path to customized prosthesis: role of the occupational therapist in the recovery of autonomy].

PubMed

Fogliaresi, Stefania; Mulè, Chiara; Borboni, Alberto; Taveggia, Giovanni

2015-01-01

The aim of the rehabilitative treatment of the amputee is to facilitate the reintegration of the patient into daily life: within social, family, and working contexts. Occupational therapy relates to 'doing', to everyday life. These are the activities carried out by individuals during daily life: catching the bus, driving a car, cooking a meal, playing cards or changing a light bulb. During the process of rehabilitation of the amputee the occupational therapist must evaluate the residual capacities of the patient, discover their needs and requirements so as to develop suitable rehabilitative strategiesfor retraining motor-skills, acceptance of the new living conditions, and social reintegration.

An analytical approach to test and design upper limb prosthesis.

PubMed

Veer, Karan

2015-01-01

In this work the signal acquiring technique, the analysis models and the design protocols of the prosthesis are discussed. The different methods to estimate the motion intended by the amputee from surface electromyogram (SEMG) signals based on time and frequency domain parameters are presented. The experiment proposed that the used techniques can help significantly in discriminating the amputee's motions among four independent activities using dual channel set-up. Further, based on experimental results, the design and working of an artificial arm have been covered under two constituents--the electronics design and the mechanical assembly. Finally, the developed hand prosthesis allows the amputated persons to perform daily routine activities easily.

Development and preliminary evaluation of a new anatomically based prosthetic alignment method for below-knee prosthesis.

PubMed

Tafti, Nahid; Karimlou, Masoud; Mardani, Mohammad Ali; Jafarpisheh, Amir Salar; Aminian, Gholam Reza; Safari, Reza

2018-04-20

The objectives of current study were to a) assess similarities and relationships between anatomical landmark-based angles and distances of lower limbs in unilateral transtibial amputees and b) develop and evaluate a new anatomically based static prosthetic alignment method. First sub-study assessed the anthropometrical differences and relationships between the lower limbs in the photographs taken from amputees. Data were analysed via paired t-test and regression analysis. Results show no significant differences in frontal and transverse planes. In the sagittal plane, the anthropometric parameters of the amputated limb were significantly correlated to the corresponding variables of the sound limb. The results served as bases for the development of a new prosthetic alignment method. The method was evaluated on a single subject study. Prosthetic alignment carried out by an experienced prosthetist was compared with such alignment adjusted by an inexperienced prosthetist but with the use of the developed method. In sagittal and frontal planes, the socket angle was tuned with respect to the shin angle, and the position of the prosthetic foot was tuned in relation to the pelvic landmarks. Further study is needed to assess the proposed method on a larger sample of amputees and prosthetists.

A comparison of upper limb amputees and patients with upper limb injuries using the Disability of the Arm, Shoulder and Hand (DASH).

PubMed

Davidson, Judith

To use the Disability of the Arm Shoulder and Hand (DASH) scale to measure the disability of patients with upper limb amputation(s) and to compare these to other upper limb injuries. All 274 patients over the age of 18 years presenting to Prince Henry Hospital in Sydney over a 4-year time frame were given the DASH assessment tool and asked to complete it under supervision of the Occupational Therapist. Patients with brachial plexus injuries, Complex Regional Pain Syndrome and bilateral upper limb amputations demonstrated significantly higher levels of disability to patients with unilateral upper limb amputations. Partial hand amputees reported a higher level of disability than major unilateral upper limb amputees. For the 48 patients who completed pre- and post-treatment assessments, there was a significant improvement in their health status. Further research is required to understand the factors that affect a patient's perceptions of their disability. Perhaps the definitive nature of an amputation and the immediate involvement of highly skilled health professionals serve to assist patients to accept their injury and therefore minimizes the level of disability.

Investigation of the syndrome of apotemnophilia and course of a cognitive-behavioural therapy.

PubMed

Braam, Arjan W; Visser, Sako; Cath, Daniëlle C; Hoogendijk, W J G

2006-01-01

The syndrome of apotemnophilia, body integrity or amputee identity disorder, is defined as the desire for amputation of a healthy limb, and may be accompanied by behaviour of pretending to be an amputee and sometimes, but not necessarily, by sexual arousal. A case history is presented of a 35-year-old man who was referred because of his desire for amputation of his left leg, without sexual connotations. The course of a combined cognitive behavioural psychotherapy with SSRI treatment is described. Symptoms showed considerable similarity with obsessive-compulsive disorder, and some similarity with body dysmorphic disorder according to DSM-IV, but the core symptom seemed to be strongly connected with a sense of identity. Treatment with a selective serotonin re-uptake inhibitor decreased levels of distress only. The effects of cognitive restructuring of the psychotherapy were limited, whereas the behavioural elements substantially reduced the behaviour of pretending to be an amputee. The rare syndrome of apotemnophilia raises unresolved questions of classification. Psychotic disorders should be ruled out carefully. The model designed in the current cognitive behavioural approach may serve as a starting point for further development of intervention protocols for this rare disorder.

Evaluation of function, performance, and preference as transfemoral amputees transition from mechanical to microprocessor control of the prosthetic knee.

PubMed

Hafner, Brian J; Willingham, Laura L; Buell, Noelle C; Allyn, Katheryn J; Smith, Douglas G

2007-02-01

To evaluate differences in function, performance, and preference between mechanical and microprocessor prosthetic knee control technologies. A-B-A-B reversal design. Home, community, and laboratory environments. Twenty-one unilateral, transfemoral amputees. Mechanical control prosthetic knee versus microprocessor control prosthetic knee (Otto Bock C-Leg). Stair rating, hill rating and time, obstacle course time, divided attention task accuracy and time, Amputee Mobility Predictor score, step activity, Prosthesis Evaluation Questionnaire score, Medical Outcomes Study 36-Item Short-Form Health Survey score, self-reported frequency of stumbles and falls, and self-reported concentration required for ambulation. Stair descent score, hill descent time, and hill sound-side step length showed significant (P<.01) improvement with the C-Leg. Users reported a significant (P<.05) decrease in frequency of stumbles and falls, frustration with falling, and difficulty in multitasking while using the microprocessor knee. Subject satisfaction with the C-Leg was significantly (P<.001) greater than the mechanical control prosthesis. The study population showed improved performance when negotiating stairs and hills, reduced frequency of stumbling and falling, and a preference for the microprocessor control C-Leg as compared with the mechanical control prosthetic knee.

Analysis of Interrelationships among Voluntary and Prosthetic Leg Joint Parameters Using Cyclograms.

PubMed

Jasni, Farahiyah; Hamzaid, Nur Azah; Mohd Syah, Nor Elleeiana; Chung, Tze Y; Abu Osman, Noor Azuan

2017-01-01

The walking mechanism of a prosthetic leg user is a tightly coordinated movement of several joints and limb segments. The interaction among the voluntary and mechanical joints and segments requires particular biomechanical insight. This study aims to analyze the inter-relationship between amputees' voluntary and mechanical coupled leg joints variables using cyclograms. From this analysis, the critical gait parameters in each gait phase were determined and analyzed if they contribute to a better powered prosthetic knee control design. To develop the cyclogram model, 20 healthy able-bodied subjects and 25 prosthesis and orthosis users (10 transtibial amputees, 5 transfemoral amputees, and 10 different pathological profiles of orthosis users) walked at their comfortable speed in a 3D motion analysis lab setting. The gait parameters (i.e., angle, moment and power for the ankle, knee and hip joints) were coupled to form 36 cyclograms relationship. The model was validated by quantifying the gait disparities of all the pathological walking by analyzing each cyclograms pairs using feed-forward neural network with backpropagation. Subsequently, the cyclogram pairs that contributed to the highest gait disparity of each gait phase were manipulated by replacing it with normal values and re-analyzed. The manipulated cyclograms relationship that showed highest improvement in terms of gait disparity calculation suggested that they are the most dominant parameters in powered-knee control. In case of transfemoral amputee walking, it was identified using this approach that at each gait sub-phase, the knee variables most responsible for closest to normal walking were: knee power during loading response and mid-stance, knee moment and knee angle during terminal stance phase, knee angle and knee power during pre-swing, knee angle at initial swing, and knee power at terminal swing. No variable was dominant during mid-swing phase implying natural pendulum effect of the lower limb between the initial and terminal swing phases. The outcome of this cyclogram adoption approach proposed an insight into the method of determining the causal effect of manipulating a particular joint's mechanical properties toward the joint behavior in an amputee's gait by determining the curve closeness, C, of the modified cyclogram curve to the normal conventional curve, to enable quantitative judgment of the effect of changing a particular parameter in the prosthetic leg gait.

The benefits of using a vacuum-assisted socket system to improve balance and gait in elderly transtibial amputees.

PubMed

Samitier, C Beatriz; Guirao, Lluis; Costea, Maria; Camós, Josep M; Pleguezuelos, Eulogio

2016-02-01

Lower limb amputation leads to impaired balance, ambulation, and transfers. Proper fit of the prosthesis is a determining factor for successful ambulation. Vacuum-assisted socket systems extract air from the socket, which decreases pistoning and probability of soft-tissue injuries and increases proprioception and socket comfort. To investigate the effect of vacuum-assisted socket system on transtibial amputees' performance-based and perceived balance, transfers, and gait. Quasi-experimental before-and-after study. Subjects were initially assessed using their prosthesis with the regular socket and re-evaluated 4 weeks after fitting including the vacuum-assisted socket system. We evaluated the mobility grade using Medicare Functional Classification Level, Berg Balance Scale, Four Square Step Test, Timed Up and Go Test, the 6-Min Walk Test, the Locomotor Capabilities Index, Satisfaction with Prosthesis (SAT-PRO questionnaire), and Houghton Scale. A total of 16 unilateral transtibial dysvascular amputees, mean age 65.12 (standard deviation = 10.15) years. Using the vacuum-assisted socket system, the patients significantly improved in balance, gait, and transfers: scores of the Berg Balance Scale increased from 45.75 (standard deviation = 6.91) to 49.06 (standard deviation = 5.62) (p < 0.01), Four Square Step Test decreased from 18.18 (standard deviation = 3.84) s to 14.97 (3.9) s (p < 0.01), Timed Up and Go Test decreased from 14.3 (standard deviation = 3.29) s to 11.56 (2.46) s (p < 0.01). The distance walked in the 6-Min Walk Test increased from 288.53 (standard deviation = 59.57) m to 321.38 (standard deviation = 72.81) m (p < 0.01). Vacuum-assisted socket systems are useful for improving balance, gait, and transfers in over-50-year-old dysvascular transtibial amputees. This study gives more insight into the use of vacuum-assisted socket systems to improve elderly transtibial dysvascular amputees' functionality and decrease their risk of falls. The use of an additional distal valve in the socket should be considered in patients with a lower activity level. © The International Society for Prosthetics and Orthotics 2014.

Determination of the effects of playing soccer on physical fitness in individuals with transtibial amputation.

PubMed

Guchan, Zehra; Bayramlar, Kezban; Ergun, Nevin

2017-06-01

The aim of this paper is to determine the effects of playing soccer on various components of physical performance such as body composition, muscular endurance, anaerobic power, flexibility, balance, and speed of individuals with transtibial amputation. Twelve amputee football players aged 26.67±7.76 years and twelve sedentary individuals aged 33±6.7 years were involved in this study. Body composition, and isotonic and isometric endurance of trunk muscles were assessed. Vertical jump test, sit-and-reach test, modified Thomas test, Berg Balance Scale, L test, and figure-of-eight walk (F8W) test were used to assess other physical fitness parameters. The Body Mass Index, waist circumference and body fat percentages of the amputee soccer players were significantly lower than the sedentary amputees (P<0.05). The endurance of back extensors was significantly higher in the soccer group (119.33±47.15 s) than the endurance in the control group (26.25±15.96 s) (P<0.001). Subjects belonging to the soccer group had significantly higher anaerobic power than those in the control group (P<0.05). Flexibility, as assessed by the sit-and-reach test was significantly higher for the soccer group (P=0.002), whereas the modified Thomas test, which is also used to measure flexibility, indicated no significant difference among both groups (P>0.05). Balance was higher in the soccer group (P=0.023). The completion period of the F8W test was significantly lower in the soccer group (4.54±0.9 s) than in the control group (7.71±2.25 s) (P<0.001). No significant difference was observed in the numbers of steps measured during the F8W test (P=0.231). This is the first study which investigates the effects of sports on the physical fitness of individuals with transtibial amputation with the inclusion of a control group. Overall findings present the benefits of participating in playing soccer on physical fitness parameters of amputees, but further studies with randomized controlled trials, with larger populations, and with other sport branches should be conducted to motivate all amputees to participate in sports.

Providing time-discrete gait information by wearable feedback apparatus for lower-limb amputees: usability and functional validation.

PubMed

Crea, Simona; Cipriani, Christian; Donati, Marco; Carrozza, Maria Chiara; Vitiello, Nicola

2015-03-01

Here we describe a novel wearable feedback apparatus for lower-limb amputees. The system is based on three modules: a pressure-sensitive insole for the measurement of the plantar pressure distribution under the prosthetic foot during gait, a computing unit for data processing and gait segmentation, and a set of vibrating elements placed on the thigh skin. The feedback strategy relies on the detection of specific gait-phase transitions of the amputated leg. Vibrating elements are activated in a time-discrete manner, simultaneously with the occurrence of the detected gait-phase transitions. Usability and effectiveness of the apparatus were successfully assessed through an experimental validation involving ten healthy volunteers.

Combined mirror visual and auditory feedback therapy for upper limb phantom pain: a case report

PubMed Central

2011-01-01

Introduction Phantom limb sensation and phantom limb pain is a very common issue after amputations. In recent years there has been accumulating data implicating 'mirror visual feedback' or 'mirror therapy' as helpful in the treatment of phantom limb sensation and phantom limb pain. Case presentation We present the case of a 24-year-old Caucasian man, a left upper limb amputee, treated with mirror visual feedback combined with auditory feedback with improved pain relief. Conclusion This case may suggest that auditory feedback might enhance the effectiveness of mirror visual feedback and serve as a valuable addition to the complex multi-sensory processing of body perception in patients who are amputees. PMID:21272334

The effectiveness of a back school program in lowerlimb amputees: a randomized controlled study.

PubMed

Anaforoğlu, Bahar; Erbahçeci, Fatih; Aksekili, Mehmet Atıf Erol

2016-06-23

A few studies have been carried out in lower limb amputees (LLAs) and they examined the incidence of and reasons for low back pain. The aim of this study was to assess the effectiveness of a back school program in LLAs with mechanical low back pain (MLBP). Forty male unilateral transfemoral amputees with MLBP were randomly allocated into two groups. A back school program was applied to Group 1 over 2 weeks. A booklet for home use was given to each participant in Group 2. Pain was assessed using a visual analogue scale. Spinal flexibility measurements were obtained. For the assessment of back pain-related disability, the Oswestry Disability Index was used. Patients were assessed at baseline, at month 1, and at month 3. At the month 1 assessment, a reduction in pain intensity and disability, and increase in spinal flexibility measurements were detected in Group 1 only (P < 0.05). At the month 3 assessment, there were improvements in all measured parameters in both groups(P < 0.05). Group 1 had better results in all parameters compared with Group 2. The back school program, combined with an exercise program, decreased pain and disability and improved the spinal flexibility significantly in LLAs with MLBP.

Elite long jumpers with below the knee prostheses approach the board slower, but take-off more effectively than non-amputee athletes.

PubMed

Willwacher, Steffen; Funken, Johannes; Heinrich, Kai; Müller, Ralf; Hobara, Hiroaki; Grabowski, Alena M; Brüggemann, Gert-Peter; Potthast, Wolfgang

2017-11-22

The use of technological aids to improve sport performance ('techno doping') and inclusion of Paralympic athletes in Olympic events are matters of ongoing debate. Recently, a long jumper with a below the knee amputation (BKA) achieved jump distances similar to world-class athletes without amputations, using a carbon fibre running-specific prosthesis (RSP). We show that athletes with BKA utilize a different, more effective take-off technique in the long jump, which provided the best athlete with BKA a performance advantage of at least 0.13 m compared to non-amputee athletes. A maximum speed constraint imposed by the use of RSPs would indicate a performance disadvantage for the long jump. We found slower maximum sprinting speeds in athletes with BKA, but did not find a difference in the overall vertical force from both legs of athletes with BKA compared to non-amputees. Slower speeds might originate from intrinsically lower sprinting abilities of athletes with BKA or from more complex adaptions in sprinting mechanics due to the biomechanical and morphological differences induced by RSPs. Our results suggest that due to different movement strategies, athletes with and without BKA should likely compete in separate categories for the long jump.

Design and Development of a Novel Upper-Limb Cycling Prosthesis

PubMed Central

Soni-Sadar, Shivam; Rowbottom, Jack; Patel, Shilen; Mathewson, Edward; Pearson, Samuel; Hutchins, David; Head, John; Hutchins, Stephen

2017-01-01

The rise in popularity of the Paralympics in recent years has created a need for effective, low-cost sports-prosthetic devices for upper-limb amputees. There are various opportunities for lower-limb amputees to participate in cycling; however, there are only few options for those with upper-limb amputations. If the individual previously participated in cycling, a cycling-specific prosthesis could allow these activities to be integrated into rehabilitation methods. This article describes the processes involved with designing, developing and manufacturing such a prosthesis. The fundamental needs of people with upper-limb amputation were assessed and realised in the prototype of a transradial terminal device with two release mechanisms, including a sliding mechanism (for falls and minor collisions) and clamping mechanism (for head-on collisions). The sliding mechanism requires the rider to exert approximately 200 N, while the clamping mechanism requires about 700 N. The force ranges can be customised to match rider requirements. Experiments were conducted in a controlled environment to demonstrate stability of the device during normal cycling. Moreover, a volunteer test-rider was able to successfully activate the release mechanism during a simulated emergency scenario. The development of this prosthesis has the potential to enable traumatic upper-limb amputees to participate in cycling for rehabilitation or recreation. PMID:29144392

Self-Recalibrating Surface EMG Pattern Recognition for Neuroprosthesis Control Based on Convolutional Neural Network

PubMed Central

Zhai, Xiaolong; Jelfs, Beth; Chan, Rosa H. M.; Tin, Chung

2017-01-01

Hand movement classification based on surface electromyography (sEMG) pattern recognition is a promising approach for upper limb neuroprosthetic control. However, maintaining day-to-day performance is challenged by the non-stationary nature of sEMG in real-life operation. In this study, we propose a self-recalibrating classifier that can be automatically updated to maintain a stable performance over time without the need for user retraining. Our classifier is based on convolutional neural network (CNN) using short latency dimension-reduced sEMG spectrograms as inputs. The pretrained classifier is recalibrated routinely using a corrected version of the prediction results from recent testing sessions. Our proposed system was evaluated with the NinaPro database comprising of hand movement data of 40 intact and 11 amputee subjects. Our system was able to achieve ~10.18% (intact, 50 movement types) and ~2.99% (amputee, 10 movement types) increase in classification accuracy averaged over five testing sessions with respect to the unrecalibrated classifier. When compared with a support vector machine (SVM) classifier, our CNN-based system consistently showed higher absolute performance and larger improvement as well as more efficient training. These results suggest that the proposed system can be a useful tool to facilitate long-term adoption of prosthetics for amputees in real-life applications. PMID:28744189

Perioperative and rehabilitation outcome after lower-limb amputation in elderly Chinese patients in Hong Kong.

PubMed

Leung, H B; Wong, W C; Wu, F C J; Guerin, J S

2004-06-01

Major amputation of the lower limb is considered the last resort when limb salvage is impossible. The aim of this study is to determine the morbidity, mortality, and rehabilitation outcome of patients that underwent a lower-limb amputation. A retrospective cohort study was conducted among 100 elderly patients who underwent a total of 120 lower-limb amputations in a regional hospital in Hong Kong from 1996 to 2001. The mean age of the amputees was 77.9 years; 58 were female. 95% of the amputations were performed because of infection with or without vascular compromise; 55 transfemoral and 60 transtibial amputations contributed 96% of the case mix. Some 43% of patients experienced early complications and 12% required re-amputation. The early (30-day) mortality rate was 15%. Only 55% of the amputees survived after 4 years. A 44% return-home rate was achieved. However, only 11% of the amputees could walk without help from other people. Although prostheses were issued to 42% of the survivors, compliance was only 53%; 24% of the survivors lost their remaining leg within 2 years. The outcome of major lower-extremity amputation remains poor. Efforts should be made to retain these limbs. When it is proven impossible, one should strive to preserve the knee joint whenever feasible.

Amputation rehabilitation and prosthetic restoration. From surgery to community reintegration.

PubMed

Esquenazi, Alberto

The purpose of this review is to summarize the literature related to the advances that have taken place in the management and rehabilitation care of limb amputation. Prostheses for the lower and upper limb amputee have changed greatly over the past several years, with advances in components, socket fabrication and fitting techniques, suspension systems and sources of power and electronic controls. Higher levels of limb amputation can now be fitted with functional prostheses, which allow more patients to achieve independent life styles. This is of particular importance for the multi-limb amputee. The rehabilitation of more traditional lower limb levels of amputation have also greatly benefited from the technological advances including energy storing feet, electronic control hydraulic knees, ankle rotators and shock absorbers to mention a few. For the upper limb amputee, myoelectric and proportional controlled terminal devices and elbow joints are now used routinely in some rehabilitation facilities. Experimental prosthetic fitting techniques and devices such as the use of osseo-implantation for suspension of the prosthesis, tension control hands or electromagnetic fluids for knee movement control will also be briefly discussed in this paper. It is possible to conclude from this review that many advances have occurred that have greatly impacted the functional outcomes of patients with limb amputation.

Effects of sensory augmentation on postural control and gait symmetry of transfemoral amputees: a case description.

PubMed

Pagel, Anna; Arieta, Alejandro Hernandez; Riener, Robert; Vallery, Heike

2016-10-01

Despite recent advances in leg prosthetics, transfemoral amputees still experience limitations in postural control and gait symmetry. It has been hypothesized that artificial sensory information might improve the integration of the prosthesis into the human sensory-motor control loops and, thus, reduce these limitations. In three transfemoral amputees, we investigated the effect of Electrotactile Moving Sensation for Sensory Augmentation (EMSSA) without training and present preliminary findings. Experimental conditions included standing with open/closed eyes on stable/unstable ground as well as treadmill walking. For standing conditions, spatiotemporal posturographic measures and sample entropy were derived from the center of pressure. For walking conditions, step length and stance duration were calculated. Conditions without feedback showed effects congruent with findings in the literature, e.g., asymmetric weight bearing and step length, and validated the collected data. During standing, with EMSSA a tendency to influence postural control in a negative way was found: Postural control was less effective and less efficient and the prosthetic leg was less involved. Sample entropy tended to decrease, suggesting that EMSSA demanded increased attention. During walking, with EMSSA no persistent positive effect was found. This contrasts the positive subjective assessment and the positive effect on one subject's step length.

Clinical field follow-up of high density polyethylene (HDPE)-Jaipur prosthetic technology for trans-femoral amputees.

PubMed

Jensen, J S; Craig, J G; Mtalo, L B; Zelaya, C M

2004-08-01

The purpose of this study was to examine the outcome of the application of the high density polyethylene (HDPE)-Jaipur prosthetic construction in fitting trans-femoral amputees in a number of projects throughout the developing world. Projects in Honduras, Uganda and India were included. One hundred and fifty eight (158) patients had been provided with the HDPE-Jaipur prosthesis and of these 72 were seen for a clinical and technical follow-up after a median of 32 months. More than half the amputees seen had amputation due to trauma and the remainder due to disease. Fabrication and fitting in the three projects was carried out by individuals who had undertaken a three week training course provided by Bhagwan Mahaveer Viklang Sahayata Samiti limb centre in Jaipur. The individuals involved had limited background training in prosthetics. Craftsmanship and fit were assessed as being poor in 86% of cases. Failure requiring replacement of components was observed in 50% of cases. There was low patient satisfaction (58%) and patient compliance (65%). The outcome was considered unsatisfactory both technically and clinically. This was a reflection of the inadequacies of the prosthetic construction, particularly the knee joint, and the inadequate training of those involved in fitting and fabrication of the devices.

Self-Recalibrating Surface EMG Pattern Recognition for Neuroprosthesis Control Based on Convolutional Neural Network.

PubMed

Zhai, Xiaolong; Jelfs, Beth; Chan, Rosa H M; Tin, Chung

2017-01-01

Hand movement classification based on surface electromyography (sEMG) pattern recognition is a promising approach for upper limb neuroprosthetic control. However, maintaining day-to-day performance is challenged by the non-stationary nature of sEMG in real-life operation. In this study, we propose a self-recalibrating classifier that can be automatically updated to maintain a stable performance over time without the need for user retraining. Our classifier is based on convolutional neural network (CNN) using short latency dimension-reduced sEMG spectrograms as inputs. The pretrained classifier is recalibrated routinely using a corrected version of the prediction results from recent testing sessions. Our proposed system was evaluated with the NinaPro database comprising of hand movement data of 40 intact and 11 amputee subjects. Our system was able to achieve ~10.18% (intact, 50 movement types) and ~2.99% (amputee, 10 movement types) increase in classification accuracy averaged over five testing sessions with respect to the unrecalibrated classifier. When compared with a support vector machine (SVM) classifier, our CNN-based system consistently showed higher absolute performance and larger improvement as well as more efficient training. These results suggest that the proposed system can be a useful tool to facilitate long-term adoption of prosthetics for amputees in real-life applications.

Energy expenditure and activity of transfemoral amputees using mechanical and microprocessor-controlled prosthetic knees.

PubMed

Kaufman, Kenton R; Levine, James A; Brey, Robert H; McCrady, Shelly K; Padgett, Denny J; Joyner, Michael J

2008-07-01

To quantify the energy efficiency of locomotion and free-living physical activity energy expenditure of transfemoral amputees using a mechanical and microprocessor-controlled prosthetic knee. Repeated-measures design to evaluate comparative functional outcomes. Exercise physiology laboratory and community free-living environment. Subjects (N=15; 12 men, 3 women; age, 42+/-9 y; range, 26-57 y) with transfemoral amputation. Research participants were long-term users of a mechanical prosthesis (20+/-10 y as an amputee; range, 3-36 y). They were fitted with a microprocessor-controlled knee prosthesis and allowed to acclimate (mean time, 18+/-8 wk) before being retested. Objective measurements of energy efficiency and total daily energy expenditure were obtained. The Prosthetic Evaluation Questionnaire was used to gather subjective feedback from the participants. Subjects demonstrated significantly increased physical activity-related energy expenditure levels in the participant's free-living environment (P=.04) after wearing the microprocessor-controlled prosthetic knee joint. There was no significant difference in the energy efficiency of walking (P=.34). When using the microprocessor-controlled knee, the subjects expressed increased satisfaction in their daily lives (P=.02). People ambulating with a microprocessor-controlled knee significantly increased their physical activity during daily life, outside the laboratory setting, and expressed an increased quality of life.

Design and Development of a Novel Upper-Limb Cycling Prosthesis.

PubMed

Tiele, Akira; Soni-Sadar, Shivam; Rowbottom, Jack; Patel, Shilen; Mathewson, Edward; Pearson, Samuel; Hutchins, David; Head, John; Hutchins, Stephen

2017-11-16

The rise in popularity of the Paralympics in recent years has created a need for effective, low-cost sports-prosthetic devices for upper-limb amputees. There are various opportunities for lower-limb amputees to participate in cycling; however, there are only few options for those with upper-limb amputations. If the individual previously participated in cycling, a cycling-specific prosthesis could allow these activities to be integrated into rehabilitation methods. This article describes the processes involved with designing, developing and manufacturing such a prosthesis. The fundamental needs of people with upper-limb amputation were assessed and realised in the prototype of a transradial terminal device with two release mechanisms, including a sliding mechanism (for falls and minor collisions) and clamping mechanism (for head-on collisions). The sliding mechanism requires the rider to exert approximately 200 N, while the clamping mechanism requires about 700 N. The force ranges can be customised to match rider requirements. Experiments were conducted in a controlled environment to demonstrate stability of the device during normal cycling. Moreover, a volunteer test-rider was able to successfully activate the release mechanism during a simulated emergency scenario. The development of this prosthesis has the potential to enable traumatic upper-limb amputees to participate in cycling for rehabilitation or recreation.

Analyzing at-home prosthesis use in unilateral upper-limb amputees to inform treatment & device design.

PubMed

Spiers, Adam J; Resnik, Linda; Dollar, Aaron M

2017-07-01

New upper limb prosthetic devices are continuously being developed by a variety of industrial, academic, and hobbyist groups. Yet, little research has evaluated the long term use of currently available prostheses in daily life activities, beyond laboratory or survey studies. We seek to objectively measure how experienced unilateral upper limb prosthesis-users employ their prosthetic devices and unaffected limb for manipulation during everyday activities. In particular, our goal is to create a method for evaluating all types of amputee manipulation, including non-prehensile actions beyond conventional grasp functions, as well as to examine the relative use of both limbs in unilateral and bilateral cases. This study employs a head-mounted video camera to record participant's hands and arms as they complete unstructured domestic tasks within their own homes. A new 'Unilateral Prosthesis-User Manipulation Taxonomy' is presented based observations from 10 hours of recorded videos. The taxonomy addresses manipulation actions of the intact hand, prostheses, bilateral activities, and environmental feature-use (aiïordances). Our preliminary results involved tagging 23 minute segments of the full videos from 3 amputee participants using the taxonomy. This resulted in over 2,300 tag instances. Observations included that non-prehensile interactions outnumbered prehensile interactions in the affected limb for users with more distal amputation that allowed arm mobility.

Thorax, pelvis and hip pattern in the frontal plane during walking in unilateral transtibial amputees: biomechanical analysis

PubMed Central

Molina-Rueda, Francisco; Alguacil-Diego, Isabel M.; Cuesta-Gómez, Alicia; Iglesias-Giménez, Javier; Martín-Vivaldi, Andrés; Miangolarra-Page, Juan C.

2014-01-01

Background: Lower limb amputees exhibit postural control deficits during standing which can affect their walking ability. Objectives: The primary purpose of the present study was to analyze the thorax, pelvis, and hip kinematics and the hip internal moment in the frontal plane during gait in subjects with Unilateral Transtibial Amputation (UTA). Method: The participants included 25 people with UTA and 25 non-amputees as control subjects. Gait analysis was performed using the Vicon(r) Motion System. We analyzed the motion of the thorax, pelvis, and hip (kinematics) as well as the hip internal moment in the frontal plane. Results: The second peak of the hip abductor moment was significantly lower on the prosthetic side than on the sound side (p=.01) and the control side (right: p=.01; left: p=.01). During middle stance, the opposite side of the pelvis was higher on the prosthetic side compared to the control side (right: p=.01: left: p=.01). Conclusions: The joint internal moment at the hip in the frontal plane was lower on the prosthetic side than on the sound side or the control side. Thorax and pelvis kinematics were altered during the stance phase on the prosthetic side, presumably because there are mechanisms which affect postural control during walking. PMID:25003278

Grasp specific and user friendly interface design for myoelectric hand prostheses.

PubMed

Mohammadi, Alireza; Lavranos, Jim; Howe, Rob; Choong, Peter; Oetomo, Denny

2017-07-01

This paper presents the design and characterisation of a hand prosthesis and its user interface, focusing on performing the most commonly used grasps in activities of daily living (ADLs). Since the operation of a multi-articulated powered hand prosthesis is difficult to learn and master, there is a significant rate of abandonment by amputees in preference for simpler devices. In choosing so, amputees chose to live with fewer features in their prosthesis that would more reliably perform the basic operations. In this paper, we look simultaneously at a hand prosthesis design method that aims for a small number of grasps, a low complexity user interface and an alternative method to the current use of EMG as a preshape selection method through the use of a simple button; to enable amputees to get to and execute the intended hand movements intuitively, quickly and reliably. An experiment is reported at the end of the paper comparing the speed and accuracy with which able-bodied naive subjects are able to select the intended preshapes through the use of a simplified EMG method and a simple button. It is shown that the button was significantly superior in the speed of successful task completion and marginally superior in accuracy (success of first attempt).

Post-amputation pain is associated with the recall of an impaired body representation in dreams-results from a nation-wide survey on limb amputees.

PubMed

Bekrater-Bodmann, Robin; Schredl, Michael; Diers, Martin; Reinhard, Iris; Foell, Jens; Trojan, Jörg; Fuchs, Xaver; Flor, Herta

2015-01-01

The experience of post-amputation pain such as phantom limb pain (PLP) and residual limb pain (RLP), is a common consequence of limb amputation, and its presence has negative effects on a person's well-being. The continuity hypothesis of dreams suggests that the presence of such aversive experiences in the waking state should be reflected in dream content, with the recalled body representation reflecting a cognitive proxy of negative impact. In the present study, we epidemiologically assessed the presence of post-amputation pain and other amputation-related information as well as recalled body representation in dreams in a sample of 3,234 unilateral limb amputees. Data on the site and time of amputation, residual limb length, prosthesis use, lifetime prevalence of mental disorders, presence of post-amputation pain, and presence of non-painful phantom phenomena were included in logistic regression analyses using recalled body representation in dreams (impaired, intact, no memory) as dependent variable. The effects of age, sex, and frequency of dream recall were controlled for. About 22% of the subjects indicated that they were not able to remember their body representation in dreams, another 24% of the amputees recalled themselves as always intact, and only a minority of less than 3% recalled themselves as always impaired. Almost 35% of the amputees dreamed of themselves in a mixed fashion. We found that lower-limb amputation as well as the presence of PLP and RLP was positively associated with the recall of an impaired body representation in dreams. The presence of non-painful phantom phenomena, however, had no influence. These results complement previous findings and indicate complex interactions of physical body appearance and mental body representation, probably modulated by distress in the waking state. The findings are discussed against the background of alterations in cognitive processes after amputation and hypotheses suggesting an innate body model.

Post-Amputation Pain Is Associated with the Recall of an Impaired Body Representation in Dreams—Results from a Nation-Wide Survey on Limb Amputees

PubMed Central

Bekrater-Bodmann, Robin; Schredl, Michael; Diers, Martin; Reinhard, Iris; Foell, Jens; Trojan, Jörg; Fuchs, Xaver; Flor, Herta

2015-01-01

The experience of post-amputation pain such as phantom limb pain (PLP) and residual limb pain (RLP), is a common consequence of limb amputation, and its presence has negative effects on a person’s well-being. The continuity hypothesis of dreams suggests that the presence of such aversive experiences in the waking state should be reflected in dream content, with the recalled body representation reflecting a cognitive proxy of negative impact. In the present study, we epidemiologically assessed the presence of post-amputation pain and other amputation-related information as well as recalled body representation in dreams in a sample of 3,234 unilateral limb amputees. Data on the site and time of amputation, residual limb length, prosthesis use, lifetime prevalence of mental disorders, presence of post-amputation pain, and presence of non-painful phantom phenomena were included in logistic regression analyses using recalled body representation in dreams (impaired, intact, no memory) as dependent variable. The effects of age, sex, and frequency of dream recall were controlled for. About 22% of the subjects indicated that they were not able to remember their body representation in dreams, another 24% of the amputees recalled themselves as always intact, and only a minority of less than 3% recalled themselves as always impaired. Almost 35% of the amputees dreamed of themselves in a mixed fashion. We found that lower-limb amputation as well as the presence of PLP and RLP was positively associated with the recall of an impaired body representation in dreams. The presence of non-painful phantom phenomena, however, had no influence. These results complement previous findings and indicate complex interactions of physical body appearance and mental body representation, probably modulated by distress in the waking state. The findings are discussed against the background of alterations in cognitive processes after amputation and hypotheses suggesting an innate body model. PMID:25742626

Development of a residuum/socket interface simulator for lower limb prosthetics.

PubMed

McGrath, Michael Paul; Gao, Jianliang; Tang, Jinghua; Laszczak, Piotr; Jiang, Liudi; Bader, Dan; Moser, David; Zahedi, Saeed

2017-03-01

Mechanical coupling at the interface between lower limb residua and prosthetic sockets plays an important role in assessing socket fitting and tissue health. However, most research lab-based lower limb prosthetic simulators to-date have implemented a rigid socket coupling. This study describes the fabrication and implementation of a lower limb residuum/socket interface simulator, designed to reproduce the forces and moments present during the key loading phases of amputee walking. An artificial residuum made with model bones encased in silicone was used, mimicking the compliant mechanical loading of a real residuum/socket interface. A 6-degree-of-freedom load cell measured the overall kinetics, having previously been incorporated into an amputee's prosthesis to collect reference data. The developed simulator was compared to a setup where a rigid pylon replaced the artificial residuum. A maximum uniaxial load of 850 N was applied, comparable to the peak vertical ground reaction force component during amputee walking. Load cell outputs from both pylon and residuum setups were compared. During weight acceptance, when including the artificial residuum, compression decreased by 10%, while during push off, sagittal bending and anterior-posterior shear showed a 25% increase and 34% decrease, respectively. Such notable difference by including a compliant residuum further highlighted the need for such an interface simulator. Subsequently, the simulator was adjusted to produce key load cell outputs briefly aligning with those from amputee walking. Force sensing resistors were deployed at load bearing anatomic locations on the residuum/socket interface to measure pressures and were compared to those cited in the literature for similar locations. The development of such a novel simulator provides an objective adjunct, using commonly available mechanical test machines. It could potentially be used to provide further insight into socket design, fit and the complex load transfer mechanics at the residuum/socket interface, as well as to evaluate the structural performance of prostheses.

Effect of Running Speed and Leg Prostheses on Mediolateral Foot Placement and Its Variability

PubMed Central

Arellano, Christopher J.; McDermott, William J.; Kram, Rodger; Grabowski, Alena M.

2015-01-01

This study examined the effects of speed and leg prostheses on mediolateral (ML) foot placement and its variability in sprinters with and without transtibial amputations. We hypothesized that ML foot placement variability would: 1. increase with running speed up to maximum speed and 2. be symmetrical between the legs of non-amputee sprinters but asymmetrically greater for the affected leg of sprinters with a unilateral transtibial amputation. We measured the midline of the body (kinematic data) and center of pressure (kinetic data) in the ML direction while 12 non-amputee sprinters and 7 Paralympic sprinters with transtibial amputations (6 unilateral, 1 bilateral) ran across a range of speeds up to maximum speed on a high-speed force measuring treadmill. We quantified ML foot placement relative to the body’s midline and its variability. We interpret our results with respect to a hypothesized relation between ML foot placement variability and lateral balance. We infer that greater ML foot placement variability indicates greater challenges with maintaining lateral balance. In non-amputee sprinters, ML foot placement variability for each leg increased substantially and symmetrically across speed. In sprinters with a unilateral amputation, ML foot placement variability for the affected and unaffected leg also increased substantially, but was asymmetric across speeds. In general, ML foot placement variability for sprinters with a unilateral amputation was within the range observed in non-amputee sprinters. For the sprinter with bilateral amputations, both affected legs exhibited the greatest increase in ML foot placement variability with speed. Overall, we find that maintaining lateral balance becomes increasingly challenging at faster speeds up to maximum speed but was equally challenging for sprinters with and without a unilateral transtibial amputation. Finally, when compared to all other sprinters in our subject pool, maintaining lateral balance appears to be the most challenging for the Paralympic sprinter with bilateral transtibial amputations. PMID:25590634

Analysis of using EMG and mechanical sensors to enhance intent recognition in powered lower limb prostheses

NASA Astrophysics Data System (ADS)

Young, A. J.; Kuiken, T. A.; Hargrove, L. J.

2014-10-01

Objective. The purpose of this study was to determine the contribution of electromyography (EMG) data, in combination with a diverse array of mechanical sensors, to locomotion mode intent recognition in transfemoral amputees using powered prostheses. Additionally, we determined the effect of adding time history information using a dynamic Bayesian network (DBN) for both the mechanical and EMG sensors. Approach. EMG signals from the residual limbs of amputees have been proposed to enhance pattern recognition-based intent recognition systems for powered lower limb prostheses, but mechanical sensors on the prosthesis—such as inertial measurement units, position and velocity sensors, and load cells—may be just as useful. EMG and mechanical sensor data were collected from 8 transfemoral amputees using a powered knee/ankle prosthesis over basic locomotion modes such as walking, slopes and stairs. An offline study was conducted to determine the benefit of different sensor sets for predicting intent. Main results. EMG information was not as accurate alone as mechanical sensor information (p < 0.05) for any classification strategy. However, EMG in combination with the mechanical sensor data did significantly reduce intent recognition errors (p < 0.05) both for transitions between locomotion modes and steady-state locomotion. The sensor time history (DBN) classifier significantly reduced error rates compared to a linear discriminant classifier for steady-state steps, without increasing the transitional error, for both EMG and mechanical sensors. Combining EMG and mechanical sensor data with sensor time history reduced the average transitional error from 18.4% to 12.2% and the average steady-state error from 3.8% to 1.0% when classifying level-ground walking, ramps, and stairs in eight transfemoral amputee subjects. Significance. These results suggest that a neural interface in combination with time history methods for locomotion mode classification can enhance intent recognition performance; this strategy should be considered for future real-time experiments.

Bioelectric analyses of an osseointegrated intelligent implant design system for amputees.

PubMed

Isaacson, Brad M; Stinstra, Jeroen G; MacLeod, Rob S; Webster, Joseph B; Beck, James P; Bloebaum, Roy D

2009-07-15

The projected number of American amputees is expected to rise to 3.6 million by 2050. Many of these individuals depend on artificial limbs to perform routine activities, but prosthetic suspensions using traditional socket technology can prove to be cumbersome and uncomfortable for a person with limb loss. Moreover, for those with high proximal amputations, limited residual limb length may prevent exoprosthesis attachment all together. Osseointegrated implant technology is a novel operative procedure which allows firm skeletal attachment between the host bone and an implant. Preliminary results in European amputees with osseointegrated implants have shown improved clinical outcomes by allowing direct transfer of loads to the bone-implant interface. Despite the apparent advantages of osseointegration over socket technology, the current rehabilitation procedures require long periods of restrictive load bearing prior which may be reduced with expedited skeletal attachment via electrical stimulation. The goal of the osseointegrated intelligent implant design (OIID) system is to make the implant part of an electrical system to accelerate skeletal attachment and help prevent periprosthetic infection. To determine optimal electrode size and placement, we initiated proof of concept with computational modeling of the electric fields and current densities that arise during electrical stimulation of amputee residual limbs. In order to provide insure patient safety, subjects with retrospective computed tomography scans were selected and three dimensional reconstructions were created using customized software programs to ensure anatomical accuracy (Seg3D and SCIRun) in an IRB and HIPAA approved study. These software packages supported the development of patient specific models and allowed for interactive manipulation of electrode position and size. Preliminary results indicate that electric fields and current densities can be generated at the implant interface to achieve the homogenous electric field distributions required to induce osteoblast migration, enhance skeletal fixation and may help prevent periprosthetic infections. Based on the electrode configurations experimented with in the model, an external two band configuration will be advocated in the future.

Validation of the virtual elevation field test method when assessing the aerodynamics of para-cyclists with a uni-lateral trans-tibial amputation.

PubMed

Dyer, Bryce; Disley, B Xavier

2018-02-01

Lower-limb amputees typically require some form of prosthetic limb to ride a bicycle for recreation or when competing. At elite-level racing speeds, aerodynamic drag can represent the majority of the resistance acting against a cyclists' forward motion. As a result, the reduction of such resistance is beneficial to an amputee whereby the form and function of the prosthetic limb can be optimized through engineering. To measure the performance of such limbs, field testing provides a cost-effective and context-specific method of aerodynamic drag measurement. However, few methods have been formally validated and none have been applied to amputees with lower-limb amputations. In this paper, an elite level para-cyclist wore two different prosthetic limb designs and had their total aerodynamic drag of a wind tunnel reference method statistically correlated against a velodrome-based virtual elevation field test method. The calculated coefficient of variation was in the range of 0.7-0.9% for the wind tunnel method and 2-3% for the virtual elevation method. A 0.03 m 2 difference was identified in the absolute values recorded between the two methods. Ultimately, both methods exhibited high levels of precision, yet relative results to each other. The virtual elevation method is proposed as a suitable technique to assess the aerodynamic drag of amputee para-cyclists. Implications for rehabilitation This assessment method will provide practitioners a reliable means of assessing the impact of changes made to prosthetics design for cyclists with limb absence. The proposed method offers a low cost and geographically accessible solution compared to others proposed in the past. This assessment method has significant potential for impact among prosthetic limb users looking to improve their cycling performance whereas previous attention in this field has been extremely limited.

The effects of graded motor imagery and its components on phantom limb pain and disability in upper and lower limb amputees: a systematic review protocol.

PubMed

Limakatso, Katleho; Corten, Lieselotte; Parker, Romy

2016-09-01

Phantom limb pain (PLP) is characterized by the anatomical shifting of neighbouring somatosensory and motor areas into a deafferented cortical area of the brain contralateral to the amputated limb. It has been shown that maladaptive neuroplasticity is positively correlated to the perception of PLP in amputees. Recent studies support the use of graded motor imagery (GMI) and its component to alleviate the severity of PLP and disability. However, there is insufficient collective empirical evidence exploring the effectiveness of these treatment modalities in amputees with PLP. This systematic review will therefore explore the effects of GMI and its individual components on PLP and disability in upper and lower limb amputees. We will utilize a customized search strategy to search PubMed, Cochrane Central register of Controlled Trials, MEDLINE, Embase, PsycINFO, PEDro, Scopus, CINAHL, LILACS, DARE, Africa-Wide Information and Web of Science. We will also look at clinicaltrials.gov ( http://www.clinicaltrials.gov/ ), Pactr.gov ( http://www.pactr.org/ ) and EU Clinical trials register ( https://www.clinicaltrialsregister.eu/ ) for ongoing research. Two independent reviewers will screen articles for methodological validity. Thereafter, data from included studies will be extracted by two independent reviewers through a customized pre-set data extraction sheet. Studies with a comparable intervention and outcome measure will be pooled for meta-analysis. Studies with high heterogeneity will be analysed through random effects model. A narrative data analysis will be considered where there is insufficient data to perform a meta-analysis. Several studies investigating the effectiveness of GMI and its different components on PLP have drawn contrasting conclusions regarding the efficacy and applicability of GMI in clinical practice. This systematic review will therefore gather and critically appraise all relevant data, to generate a substantial conclusion and recommendations for clinical practice and research on this subject. PROSPERO CRD42016036471.

The SmartHand transradial prosthesis

PubMed Central

2011-01-01

Background Prosthetic components and control interfaces for upper limb amputees have barely changed in the past 40 years. Many transradial prostheses have been developed in the past, nonetheless most of them would be inappropriate if/when a large bandwidth human-machine interface for control and perception would be available, due to either their limited (or inexistent) sensorization or limited dexterity. SmartHand tackles this issue as is meant to be clinically experimented in amputees employing different neuro-interfaces, in order to investigate their effectiveness. This paper presents the design and on bench evaluation of the SmartHand. Methods SmartHand design was bio-inspired in terms of its physical appearance, kinematics, sensorization, and its multilevel control system. Underactuated fingers and differential mechanisms were designed and exploited in order to fit all mechatronic components in the size and weight of a natural human hand. Its sensory system was designed with the aim of delivering significant afferent information to the user through adequate interfaces. Results SmartHand is a five fingered self-contained robotic hand, with 16 degrees of freedom, actuated by 4 motors. It integrates a bio-inspired sensory system composed of 40 proprioceptive and exteroceptive sensors and a customized embedded controller both employed for implementing automatic grasp control and for potentially delivering sensory feedback to the amputee. It is able to perform everyday grasps, count and independently point the index. The weight (530 g) and speed (closing time: 1.5 seconds) are comparable to actual commercial prostheses. It is able to lift a 10 kg suitcase; slippage tests showed that within particular friction and geometric conditions the hand is able to stably grasp up to 3.6 kg cylindrical objects. Conclusions Due to its unique embedded features and human-size, the SmartHand holds the promise to be experimentally fitted on transradial amputees and employed as a bi-directional instrument for investigating -during realistic experiments- different interfaces, control and feedback strategies in neuro-engineering studies. PMID:21600048

Recommended number of strides for automatic assessment of gait symmetry and regularity in above-knee amputees by means of accelerometry and autocorrelation analysis

PubMed Central

2012-01-01

Background Symmetry and regularity of gait are essential outcomes of gait retraining programs, especially in lower-limb amputees. This study aims presenting an algorithm to automatically compute symmetry and regularity indices, and assessing the minimum number of strides for appropriate evaluation of gait symmetry and regularity through autocorrelation of acceleration signals. Methods Ten transfemoral amputees (AMP) and ten control subjects (CTRL) were studied. Subjects wore an accelerometer and were asked to walk for 70 m at their natural speed (twice). Reference values of step and stride regularity indices (Ad1 and Ad2) were obtained by autocorrelation analysis of the vertical and antero-posterior acceleration signals, excluding initial and final strides. The Ad1 and Ad2 coefficients were then computed at different stages by analyzing increasing portions of the signals (considering both the signals cleaned by initial and final strides, and the whole signals). At each stage, the difference between Ad1 and Ad2 values and the corresponding reference values were compared with the minimum detectable difference, MDD, of the index. If that difference was less than MDD, it was assumed that the portion of signal used in the analysis was of sufficient length to allow reliable estimation of the autocorrelation coefficient. Results All Ad1 and Ad2 indices were lower in AMP than in CTRL (P < 0.0001). Excluding initial and final strides from the analysis, the minimum number of strides needed for reliable computation of step symmetry and stride regularity was about 2.2 and 3.5, respectively. Analyzing the whole signals, the minimum number of strides increased to about 15 and 20, respectively. Conclusions Without the need to identify and eliminate the phases of gait initiation and termination, twenty strides can provide a reasonable amount of information to reliably estimate gait regularity in transfemoral amputees. PMID:22316184

The BADER Consortium

DTIC Science & Technology

2015-10-01

established use in  orthopedic /amputation  research  in amputee populations and have documented the relevant  research   on the psychometric properties and...established use in  orthopedic /amputation  research  in amputee populations have been identified.  The library has recently being updated  with recent...consult on the BIOM proposal and to review and discuss  research  agendas.    Core staff will schedule a meeting at WRNMMC to meet with  Orthopedic  and

Metabolics of stair ascent with a powered transfemoral prosthesis.

PubMed

Ledoux, E D; Lawson, B E; Shultz, A H; Bartlett, H L; Goldfarb, M

2015-01-01

This paper evaluates the effectiveness of a powered knee and ankle prosthesis for stair ascent through a metabolic assessment comparing energy expenditure of a single transfemoral amputee subject while ascending stairs with the powered prosthesis relative to his passive daily use device, as well as comparing the kinematics and kinetics obtained with the passive prosthesis to healthy biomechanics. The subject wore a portable system that measured pulmonary gaseous exchange rates of oxygen and carbon dioxide while he ascended stairs with each of the prostheses in alternating tests. The results indicated that the amputee's energy expenditure decreased by 32 percent while climbing with the powered prosthesis as compared to his passive one, and the kinematics and kinetics achieved were representative of healthy biomechanics.

Control of Prosthetic Hands via the Peripheral Nervous System

PubMed Central

Ciancio, Anna Lisa; Cordella, Francesca; Barone, Roberto; Romeo, Rocco Antonio; Bellingegni, Alberto Dellacasa; Sacchetti, Rinaldo; Davalli, Angelo; Di Pino, Giovanni; Ranieri, Federico; Di Lazzaro, Vincenzo; Guglielmelli, Eugenio; Zollo, Loredana

2016-01-01

This paper intends to provide a critical review of the literature on the technological issues on control and sensorization of hand prostheses interfacing with the Peripheral Nervous System (i.e., PNS), and their experimental validation on amputees. The study opens with an in-depth analysis of control solutions and sensorization features of research and commercially available prosthetic hands. Pros and cons of adopted technologies, signal processing techniques and motion control solutions are investigated. Special emphasis is then dedicated to the recent studies on the restoration of tactile perception in amputees through neural interfaces. The paper finally proposes a number of suggestions for designing the prosthetic system able to re-establish a bidirectional communication with the PNS and foster the prosthesis natural control. PMID:27092041

Improving the Robustness of Real-Time Myoelectric Pattern Recognition against Arm Position Changes in Transradial Amputees

PubMed Central

Geng, Yanjuan; Wei, Yue

2017-01-01

Previous studies have showed that arm position variations would significantly degrade the classification performance of myoelectric pattern-recognition-based prosthetic control, and the cascade classifier (CC) and multiposition classifier (MPC) have been proposed to minimize such degradation in offline scenarios. However, it remains unknown whether these proposed approaches could also perform well in the clinical use of a multifunctional prosthesis control. In this study, the online effect of arm position variation on motion identification was evaluated by using a motion-test environment (MTE) developed to mimic the real-time control of myoelectric prostheses. The performance of different classifier configurations in reducing the impact of arm position variation was investigated using four real-time metrics based on dataset obtained from transradial amputees. The results of this study showed that, compared to the commonly used motion classification method, the CC and MPC configurations improved the real-time performance across seven classes of movements in five different arm positions (8.7% and 12.7% increments of motion completion rate, resp.). The results also indicated that high offline classification accuracy might not ensure good real-time performance under variable arm positions, which necessitated the investigation of the real-time control performance to gain proper insight on the clinical implementation of EMG-pattern-recognition-based controllers for limb amputees. PMID:28523276

Energy Expenditure and Activity of Transfemoral Amputees Using Mechanical and Microprocessor-Controlled Prosthetic Knees

PubMed Central

Kaufman, Kenton R.; Levine, James A.; Brey, Robert H.; McCrady, Shelly K.; Padgett, Denny J.; Joyner, Michael J.

2009-01-01

Objective To quantify the energy efficiency of locomotion and free-living physical activity energy expenditure of transfemoral amputees using a mechanical and microprocessor-controlled prosthetic knee. Design Repeated-measures design to evaluate comparative functional outcomes. Setting Exercise physiology laboratory and community free-living environment. Participants Subjects (N=15; 12 men, 3 women; age, 42±9y; range, 26 –57y) with transfemoral amputation. Intervention Research participants were long-term users of a mechanical prosthesis (20±10y as an amputee; range, 3–36y). They were fitted with a microprocessor-controlled knee prosthesis and allowed to acclimate (mean time, 18±8wk) before being retested. Main Outcome Measures Objective measurements of energy efficiency and total daily energy expenditure were obtained. The Prosthetic Evaluation Questionnaire was used to gather subjective feedback from the participants. Results Subjects demonstrated significantly increased physical activity–related energy expenditure levels in the participant’s free-living environment (P=.04) after wearing the microprocessor-controlled prosthetic knee joint. There was no significant difference in the energy efficiency of walking (P=.34). When using the microprocessor-controlled knee, the subjects expressed increased satisfaction in their daily lives (P=.02). Conclusions People ambulating with a microprocessor-controlled knee significantly increased their physical activity during daily life, outside the laboratory setting, and expressed an increased quality of life. PMID:18586142

Artificial redirection of sensation from prosthetic fingers to the phantom hand map on transradial amputees: vibrotactile versus mechanotactile sensory feedback.

PubMed

Antfolk, Christian; D'Alonzo, Marco; Controzzi, Marco; Lundborg, Göran; Rosén, Birgitta; Sebelius, Fredrik; Cipriani, Christian

2013-01-01

This work assesses the ability of transradial amputees to discriminate multi-site tactile stimuli in sensory discrimination tasks. It compares different sensory feedback modalities using an artificial hand prosthesis in: 1) a modality matched paradigm where pressure recorded on the five fingertips of the hand was fed back as pressure stimulation on five target points on the residual limb; and 2) a modality mismatched paradigm where the pressures were transformed into mechanical vibrations and fed back. Eight transradial amputees took part in the study and were divided in two groups based on the integrity of their phantom map; group A had a complete phantom map on the residual limb whereas group B had an incomplete or nonexisting map. The ability in localizing stimuli was compared with that of 10 healthy subjects using the vibration feedback and 11 healthy subjects using the pressure feedback (in a previous study), on their forearms, in similar experiments. Results demonstrate that pressure stimulation surpassed vibrotactile stimulation in multi-site sensory feedback discrimination. Furthermore, we demonstrate that subjects with a detailed phantom map had the best discrimination performance and even surpassed healthy participants for both feedback paradigms whereas group B had the worst performance overall. Finally, we show that placement of feedback devices on a complete phantom map improves multi-site sensory feedback discrimination, independently of the feedback modality.

Quality of life in survivors of a primary bone tumour: a systematic review.

PubMed

Eiser, C; Grimer, R J

1999-01-01

Purpose. We conducted a systematic search of published literature, to assess (i) quality of life (QoL) for survivors of a bone tumour compared with the normal population; (ii) QoL implications following amputation, successful or failed limb salvage; (iii) adaptation of young children to amputation compared with older children or adolescents.Methods. Electronic databases were searched including Medline, PsycLIT and Cinahl covering the years 1982- 1998.Results. We identified 11 studies. Regardless of treatment, physical functioning was poor compared with population norms or healthy siblings.There was less consistent evidence regarding emotional functioning. Seven studies compared functioning in amputees and limb salvage patients.Two reported advantages in physical function for the limb salvage group, one for the amputees and the rest no differences. Evidence about social functioning or marriage is inconclusive, but there are suggestions that amputees report more job discrimination.Discussion. The literature is inconclusive, largely because of methodological problems. These include small and non-representative samples, and lack of sensitive and appropriate measures. Specific gaps in the literature include very little work concerned with psychological outcomes for children, or for those experiencing failed limb salvage. More attention needs to be given to gender differences in emotional response to traumatic surgery.The implications of the results for helping families balance the merits of different treatments are discussed.

Treatment for the service member: a description of innovative interventions.

PubMed

Yancosek, Katie; Daugherty, Stephanie E; Cancio, Leonard

2008-01-01

This article describes advances to the rehabilitation programs at major military medical centers since the onset of operations in Iraq and Afghanistan. The demands on military health care in times of war produce advances in the various rehabilitation professions. This article describes two programs that use new technologies for the care of military patients with devastating injuries to the upper extremity. One project relates to the application of voice-sensitive technology. The other project describes the utilization of virtual reality technology through a Firearm Training System. The article also explains an adaptive sports program and how recreation is part of a robust community reintegration program. Lastly, this article discusses the Center for the Intrepid, which is one of two new amputee care centers built to support the advanced rehabilitation of war-wounded amputees.

Revealing the neural fingerprints of a missing hand.

PubMed

Kikkert, Sanne; Kolasinski, James; Jbabdi, Saad; Tracey, Irene; Beckmann, Christian F; Johansen-Berg, Heidi; Makin, Tamar R

2016-08-23

The hand area of the primary somatosensory cortex contains detailed finger topography, thought to be shaped and maintained by daily life experience. Here we utilise phantom sensations and ultra high-field neuroimaging to uncover preserved, though latent, representation of amputees' missing hand. We show that representation of the missing hand's individual fingers persists in the primary somatosensory cortex even decades after arm amputation. By demonstrating stable topography despite amputation, our finding questions the extent to which continued sensory input is necessary to maintain organisation in sensory cortex, thereby reopening the question what happens to a cortical territory once its main input is lost. The discovery of persistent digit topography of amputees' missing hand could be exploited for the development of intuitive and fine-grained control of neuroprosthetics, requiring neural signals of individual digits.

An instrument for monitoring stump oedema and shrinkage in amputees.

PubMed

Fernie, G R; Holliday, P J; Lobb, R J

1978-08-01

A new system for measuring the cross-sectional area profiles of amputation stumps and whole limbs has been designed at the Amputee Research Centre. The instrument consists of a cylindrical tank supported on an elevator. The tank is raised to the height of the amputation stump and filled with water. A graph of the cross-sectional area profile of the amputation stump is generated by a mini-computer as the elevator descends. The cross-sectional area (A) is calculated from the expression: formula: (see text) where Hw = height of water in the tank He = height of the elevator Ac = a constant, related to the size of the measuring tank. This paper describes the instrument, which may find application in many other areas where there is a need to study shape.

A combined kinematic and kinetic analysis at the residuum/socket interface of a knee-disarticulation amputee.

PubMed

Tang, Jinghua; McGrath, Michael; Hale, Nick; Jiang, Liudi; Bader, Dan; Laszczak, Piotr; Moser, David; Zahedi, Saeed

2017-11-01

The bespoke interface between a lower limb residuum and a prosthetic socket is critical for an amputee's comfort and overall rehabilitation outcomes. Analysis of interface kinematics and kinetics is important to gain full understanding of the interface biomechanics, which could aid clinical socket fit, rehabilitation and amputee care. This pilot study aims to investigate the dynamic correlation between kinematic movement and kinetic stresses at the interface during walking tests on different terrains. One male, knee disarticulation amputee participated in the study. He was asked to walk on both a level surface and a 5° ramped surface. The movement between the residuum and the socket was evaluated by the angular and axial couplings, based on the outputs from a 3D motion capture system. The corresponding kinetic stresses at anterior-proximal (AP), posterior-proximal (PP) and anterior-distal (AD) locations of the residuum were measured, using individual stress sensors. Approximately 8° of angular coupling and up to 32 mm of axial coupling were measured when walking on different terrains. The direction of the angular coupling shows strong correlation with the pressure difference between the PP and AP sensors. Higher pressure was obtained at the PP location than the AP location during stance phase, associated with the direction of the angular coupling. A strong correlation between axial coupling length, L, and longitudinal shear was also evident at the PP and AD locations i.e. the shortening of L corresponds to the increase of shear in the proximal direction. Although different terrains did not affect these correlations in principle, interface kinematic and kinetic values suggested that gait changes can induce modifications to the interface biomechanics. It is envisaged that the reported techniques could be potentially used to provide combined kinematics and kinetics for the understanding of biomechanics at the residuum/socket interface, which may play an important role in the clinical assessment of prosthetic component settings, including socket fit quality. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

Classification of motor intent in transradial amputees using sonomyography and spatio-temporal image analysis

NASA Astrophysics Data System (ADS)

Hariharan, Harishwaran; Aklaghi, Nima; Baker, Clayton A.; Rangwala, Huzefa; Kosecka, Jana; Sikdar, Siddhartha

2016-04-01

In spite of major advances in biomechanical design of upper extremity prosthetics, these devices continue to lack intuitive control. Conventional myoelectric control strategies typically utilize electromyography (EMG) signal amplitude sensed from forearm muscles. EMG has limited specificity in resolving deep muscle activity and poor signal-to-noise ratio. We have been investigating alternative control strategies that rely on real-time ultrasound imaging that can overcome many of the limitations of EMG. In this work, we present an ultrasound image sequence classification method that utilizes spatiotemporal features to describe muscle activity and classify motor intent. Ultrasound images of the forearm muscles were obtained from able-bodied subjects and a trans-radial amputee while they attempted different hand movements. A grid-based approach is used to test the feasibility of using spatio-temporal features by classifying hand motions performed by the subjects. Using the leave-one-out cross validation on image sequences acquired from able-bodied subjects, we observe that the grid-based approach is able to discern four hand motions with 95.31% accuracy. In case of the trans-radial amputee, we are able to discern three hand motions with 80% accuracy. In a second set of experiments, we study classification accuracy by extracting spatio-temporal sub-sequences the depict activity due to the motion of local anatomical interfaces. Short time and space limited cuboidal sequences are initially extracted and assigned an optical flow behavior label, based on a response function. The image space is clustered based on the location of cuboids and features calculated from the cuboids in each cluster. Using sequences of known motions, we extract feature vectors that describe said motion. A K-nearest neighbor classifier is designed for classification experiments. Using the leave-one-out cross validation on image sequences for an amputee subject, we demonstrate that the classifier is able to discern three important hand motions with an accuracy of 93.33% accuracy, 91-100% precision and 80-100% recall rate. We anticipate that ultrasound imaging based methods will address some limitations of conventional myoelectric sensing, while adding advantages inherent to ultrasound imaging.

[Knee disarticulation and through-knee amputation].

PubMed

Baumgartner, R

2011-10-01

A knee disarticulation or a through-knee stump is superior compared to a transfemoral stump. The thigh muscles are all preserved, and the muscle balance remains undisturbed. The range of motion of the hip joint is not limited. The bulbous shape of the stump allows full weight bearing at the stump end and can easily be fitted with a prosthesis. An amputee with a bilateral knee disarticulation is able to walk "barefoot". A more distal amputation level, e.g., an ultra-short transtibial amputation, is not possible. Important alternative to transfemoral amputations. Possible for any etiology except for Buerger-Winiwarter's disease. New indications are infected and loosened total knee replacements. Preservation of the knee joint is possible. Knee disarticulation is a very atraumatic procedure, compared to transfemoral amputations. Neither bones nor muscles have to be severed, just skin, ligaments, vessels, and nerves. Even the meniscal cartilages may be left in place to act as axial shock absorbers. The cartilage of the femur is not resected, but only bevelled in case of osteoarthritis. There are no tendon attachments or myoplastic procedures necessary. The patella remains in place and is held in position only by the retinacula. Skin closure must be performed without the slightest tension, and if possible not in the weight-bearing area. Transcondylar amputations across the femoral condyles only are indicated when there are not sufficient soft tissues for wound closure of a knee disarticulation. Alternatives as the techniques of Gritti, Klaes, and Eigler, the shortening of the femur and the Sauerbruch's rotation plasty [14] are presented and discussed. The risk of decubital ulcers is rather high. Correct bandaging of the stump is, therefore, particularly important. Prosthetic fitting is possible 3-6 weeks after surgery. The type of prosthesis depends on the amputee's activity level. The superior performance of amputees with knee disarticulations in sports prove the superiority of that amputation level compared to transfemoral amputees. However, because less than 5% of amputations are knee disarticulations, statements about statistical significance cannot be made. On the other hand, one should do everything to preserve an ultra-short transtibial stump.

Insurance Fairness for Amputees Act

THOMAS, 112th Congress

Sen. Snowe, Olympia J. [R-ME

2011-04-08

Senate - 04/08/2011 Read twice and referred to the Committee on Health, Education, Labor, and Pensions. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

Limb Loss

MedlinePlus

... in amputation. Injuries, including from traffic accidents and military combat Cancer Birth defects Some amputees have phantom pain, which is the feeling of pain in the missing limb. Other physical problems include surgical complications and skin problems, if you ...

Rehand: Realistic electric prosthetic hand created with a 3D printer.

PubMed

Yoshikawa, Masahiro; Sato, Ryo; Higashihara, Takanori; Ogasawara, Tsukasa; Kawashima, Noritaka

2015-01-01

Myoelectric prosthetic hands provide an appearance with five fingers and a grasping function to forearm amputees. However, they have problems in weight, appearance, and cost. This paper reports on the Rehand, a realistic electric prosthetic hand created with a 3D printer. It provides a realistic appearance that is same as the cosmetic prosthetic hand and a grasping function. A simple link mechanism with one linear actuator for grasping and 3D printed parts achieve low cost, light weight, and ease of maintenance. An operating system based on a distance sensor provides a natural operability equivalent to the myoelectric control system. A supporter socket allows them to wear the prosthetic hand easily. An evaluation using the Southampton Hand Assessment Procedure (SHAP) demonstrated that an amputee was able to operate various objects and do everyday activities with the Rehand.

Finite element analysis of the contact interface between trans-femoral stump and prosthetic socket.

PubMed

Zhang, Linlin; Zhu, Ming; Shen, Ling; Zheng, Feng

2013-01-01

Transfemoral amputees need prosthetic devices after amputation surgery, and the interface pressure between the residual limb and prosthetic socket has a significant effect on an amputee's satisfaction and comfort. The purpose of this study was to build a nonlinear finite element model to investigate the interface pressure between the above-knee residual limb and its prosthetic socket. The model was three-dimensional (3D) with consideration of nonlinear boundary conditions. Contact analysis was used to simulate the friction conditions between skin and the socket. The normal stresses up to 80.57 kPa at the distal end of the soft tissue. The longitudinal and circumferential shear stress distributions at the limb-socket interface were also simulated. This study explores the influences of load transfer between trans-femoral residual limb and its prosthetic socket.

Standing stability enhancement with an intelligent powered transfemoral prosthesis.

PubMed

Lawson, Brian Edward; Varol, Huseyin Atakan; Goldfarb, Michael

2011-09-01

The authors have developed a ground-adaptive standing controller for a powered knee and ankle prosthesis which is intended to enhance the standing stability of transfemoral amputees. The finite-state-based controller includes a ground-searching phase, a slope estimation phase, and a joint impedance modulation phase, which together enable the prosthesis to quickly conform to the ground and provide stabilizing assistance to the user. In order to assess the efficacy of the ground-adaptive standing controller, the control approach was implemented on a powered knee and ankle prosthesis, and experimental data were collected on an amputee subject for a variety of standing conditions. Results indicate that the controller can estimate the ground slope within ±1° over a range of ±15°, and that it can provide appropriate joint impedances for standing on slopes within this range.

Progressive upper limb prosthetics.

PubMed

Lake, Chris; Dodson, Robert

2006-02-01

The field of upper extremity prosthetics is a constantly changing arena as researchers and prosthetists strive to bridge the gap between prosthetic reality and upper limb physiology. With the further development of implantable neurologic sensing devices and targeted muscle innervation (discussed elsewhere in this issue), the challenge of limited input to control vast outputs promises to become a historical footnote in the future annals of upper limb prosthetics. Soon multidextrous terminal devices, such as that found in the iLimb system(Touch EMAS, Inc., Edinburgh, UK), will be a clinical reality (Fig. 22). Successful prosthetic care depends on good communication and cooperation among the surgeon, the amputee, the rehabilitation team, and the scientists harnessing the power of technology to solve real-life challenges. If the progress to date is any indication, amputees of the future will find their dreams limited only by their imagination.

Phantom Limbs, Neuroprosthetics, and the Developmental Origins of Embodiment.

PubMed

Blumberg, Mark S; Dooley, James C

2017-10-01

Amputees who wish to rid themselves of a phantom limb must weaken the neural representation of the absent limb. Conversely, amputees who wish to replace a lost limb must assimilate a neuroprosthetic with the existing neural representation. Whether we wish to remove a phantom limb or assimilate a synthetic one, we will benefit from knowing more about the developmental process that enables embodiment. A potentially critical contributor to that process is the spontaneous activity - in the form of limb twitches - that occurs exclusively and abundantly during active (REM) sleep, a particularly prominent state in early development. The sensorimotor circuits activated by twitching limbs, and the developmental context in which activation occurs, could provide a roadmap for creating neuroprosthetics that feel as if they are part of the body. Copyright © 2017 Elsevier Ltd. All rights reserved.

A questionnaire survey of the effect of different interface types on patient satisfaction and perceived problems among trans-tibial amputees.

PubMed

Van de Weg, F B; Van der Windt, D A W M

2005-12-01

The objectives were to investigate the effect of three different interface types on consumer satisfaction and perceived problems among trans-tibial amputees in the Netherlands. A postal questionnaire (based on the Prosthesis Evaluation Questionnaire) was sent to 353 patients. Responders were classified in three groups of interface types: polyethylene foam (PEF) inserts, silicone liners (SIL), and polyurethane liners (PUL). Differences concerning satisfaction and problems between interface types were computed and adjusted for potential confounding by age, gender, reason for amputation and time since first prosthesis. A total of 220 patients responded (62%). Patients wearing liners reported a significantly poorer durability and higher maintenance time compared with patients using PEF inserts. Sum-scores for satisfaction or problems did not show any significant differences between groups. Analysis of individual items showed a significant difference only for satisfaction with sitting and with walking on uneven terrain in favour of PEF inserts. In contrast to most studies, interface type was included as a possible determinant of customer use, satisfaction, and perceived problems. The perceived differences between the three suspension types are to a large extent small and non-significant. The findings do not support liner prescription as a matter of course for all trans-tibial amputees. A careful analysis of patients' preferences should be made to determine the best course of action. Further studies, preferably prospective, need to be conducted to determine which systems are most comfortable and offer least complaints.

A Bioimpedance Analysis Platform for Amputee Residual Limb Assessment.

PubMed

Sanders, Joan E; Moehring, Mark A; Rothlisberger, Travis M; Phillips, Reid H; Hartley, Tyler; Dietrich, Colin R; Redd, Christian B; Gardner, David W; Cagle, John C

2016-08-01

The objective of this research was to develop a bioimpedance platform for monitoring fluid volume in residual limbs of people with trans-tibial limb loss using prostheses. A customized multifrequency current stimulus profile was sent to thin flat electrodes positioned on the thigh and distal residual limb. The applied current signal and sensed voltage signals from four pairs of electrodes located on the anterior and posterior surfaces were demodulated into resistive and reactive components. An established electrical model (Cole) and segmental limb geometry model were used to convert results to extracellular and intracellular fluid volumes. Bench tests and testing on amputee participants were conducted to optimize the stimulus profile and electrode design and layout. The proximal current injection electrode needed to be at least 25 cm from the proximal voltage sensing electrode. A thin layer of hydrogel needed to be present during testing to ensure good electrical coupling. Using a burst duration of 2.0 ms, intermission interval of 100 μs, and sampling delay of 10 μs at each of 24 frequencies except 5 kHz, which required a 200-μs sampling delay, the system achieved a sampling rate of 19.7 Hz. The designed bioimpedance platform allowed system settings and electrode layouts and positions to be optimized for amputee limb fluid volume measurement. The system will be useful toward identifying and ranking prosthetic design features and participant characteristics that impact residual limb fluid volume.

Influence of malalignment on socket reaction moments during gait in amputees with transtibial prostheses.

PubMed

Boone, David A; Kobayashi, Toshiki; Chou, Teri G; Arabian, Adam K; Coleman, Kim L; Orendurff, Michael S; Zhang, Ming

2013-04-01

Alignment - the process and measured orientation of the prosthetic socket relative to the foot - is important for proper function of a transtibial prosthesis. Prosthetic alignment is performed by prosthetists using visual gait observation and amputees' feedback. The aim of this study was to investigate the effect of transtibial prosthesis malalignment on the moments measured at the base of the socket: the socket reaction moments. Eleven subjects with transtibial amputation were recruited from the community. An instrumented prosthesis alignment component was used to measure socket reaction moments during ambulation under 17 alignment conditions, including nominally aligned using conventional clinical methods, and angle perturbations of 3° and 6° (flexion, extension, abduction, and adduction) and translation perturbations of 5mm and 10mm (anterior, posterior, lateral, and medial) referenced from the nominal alignment. Coronal alignment perturbations caused systematic changes in the coronal socket reaction moments. All angle and translation perturbations revealed statistically significant differences on coronal socket reaction moments compared to the nominal alignment at 30% and 75% of stance phase (P<0.05). The effect of sagittal alignment perturbations on sagittal socket reaction moments was not as responsive as that of the coronal perturbations. The sagittal angle and translation perturbations of the socket led to statistically significant changes in minimum moment, maximum moment, and moments at 45% of stance phase in the sagittal plane. Therefore, malalignment affected the socket reaction moments in amputees with transtibial prostheses. Copyright © 2012 Elsevier B.V. All rights reserved.

Patient-specific interface pressure case study at transradial prosthetic socket: comparison trials between ICRC polypropylene socket and air splint socket.

PubMed

Abd Razak, Nasrul A; Abu Osman, Noor A; Ali, Sadeeq A; Gholizadeh, Hossein

2016-01-15

While considering how important the interface between the amputees with the prostheses socket, we have carried out research to compare the gradient pressure occur at the interface socket that may lead to the discomforting effects to the user using common ICRC polypropylene socket and air splint socket. Not Applicable SETTING: Not Applicable POPULATION: The subject was a 23 year old who suffered a traumatic defect on the right arm caused by higher electrical volt. F-Socket sensors have been used to measure dynamic socket interface pressure for the transradial amputee wearer during static and dynamic movements. The printed circuit with a thickness of 0.18 mm is equipped between the socket and the surface of the residual limb. Two F-Socket sensor is required to cover the entire socket surface attached to the residual limb. The average of 10 trials made on prosthetic user using both type of sockets for static and dynamic movements was recorded. The pressure gradient shows that the circumference of the socket interface for the ICRC polypropylene socket gives the most pressure distributions to the amputees compared to the pressure gradient for the air splint socket. The pressure gradient for ICRC socket increased consistently when the user makes movements while for the air splint socket remain constantly. The specific interface pressure occur at the socket interface help in determine the comfort and pain of the socket design and improve the correlation between the user and the prosthesis.

On Design and Implementation of Neural-Machine Interface for Artificial Legs

PubMed Central

Zhang, Xiaorong; Liu, Yuhong; Zhang, Fan; Ren, Jin; Sun, Yan (Lindsay); Yang, Qing

2011-01-01

The quality of life of leg amputees can be improved dramatically by using a cyber physical system (CPS) that controls artificial legs based on neural signals representing amputees’ intended movements. The key to the CPS is the neural-machine interface (NMI) that senses electromyographic (EMG) signals to make control decisions. This paper presents a design and implementation of a novel NMI using an embedded computer system to collect neural signals from a physical system - a leg amputee, provide adequate computational capability to interpret such signals, and make decisions to identify user’s intent for prostheses control in real time. A new deciphering algorithm, composed of an EMG pattern classifier and a post-processing scheme, was developed to identify the user’s intended lower limb movements. To deal with environmental uncertainty, a trust management mechanism was designed to handle unexpected sensor failures and signal disturbances. Integrating the neural deciphering algorithm with the trust management mechanism resulted in a highly accurate and reliable software system for neural control of artificial legs. The software was then embedded in a newly designed hardware platform based on an embedded microcontroller and a graphic processing unit (GPU) to form a complete NMI for real time testing. Real time experiments on a leg amputee subject and an able-bodied subject have been carried out to test the control accuracy of the new NMI. Our extensive experiments have shown promising results on both subjects, paving the way for clinical feasibility of neural controlled artificial legs. PMID:22389637

Comparing the surgical timelines of military and civilians traumatic lower limb amputations

PubMed Central

Staruch, R.M.T.; Jackson, P.C.; Hodson, J.; Yim, G.; Foster, M.A.; Cubison, T.; Jeffery, S.L.A.

2016-01-01

The care and challenges of injured service have been well documented in the literature from a variety of specialities. The aim of this study was to analyse the surgical timelines of military and civilian traumatic amputees and compare the surgical and resuscitative interventions. A retrospective review of patient notes was undertaken. Military patients were identified from the Joint Theatre Trauma Registry (JTTR) in 2009. Civilian patients were identified using the hospital informatics database. Patient demographics, treatment timelines as well as surgical and critical care interventions were reviewed. In total 71 military patients sustained traumatic amputations within this time period. This represented 11% of the total injury demographic in 2009. Excluding upper limb amputees 46 patients sustained lower extremity amputations. These were investigated further. In total 21 civilian patients were identified in a 7-year period. Analysis revealed there was a statistically significant difference between patient age, ITU length of stay, blood products used and number of surgical procedures between military and civilian traumatic amputees. This study identified that military patients were treated for longer in critical care and required more surgical interventions for their amputations. Despite this, their time to stump closure and length of stay were not statistically different compared to civilian patients. Such observations reflect the importance of an Orthoplastic approach, as well as daily surgical theatre co-ordination and weekly multi-disciplinary meetings in providing optimal care for these complex patients. This study reports the epidemiological observed differences between two lower limb trauma groups. PMID:26958343

Evaluation of transradial body-powered prostheses using a robotic simulator.

PubMed

Ayub, Rafi; Villarreal, Dario; Gregg, Robert D; Gao, Fan

2017-04-01

Transradial body-powered prostheses are extensively used by upper-limb amputees. This prosthesis requires large muscle forces and great concentration by the patient, often leading to discomfort, muscle fatigue, and skin breakdown, limiting the capacity of the amputee to conduct daily activities. Since body-powered prostheses are commonplace, understanding their optimal operation to mitigate these drawbacks would be clinically meaningful. To find the optimal operation of the prosthesis where the activation force is minimized and the grip force is maximized. Experimental design. A computer-controlled robotic amputee simulator capable of rapidly testing multiple elbow, shoulder, and scapular combinations of the residual human arm was constructed. It was fitted with a transradial prosthesis and used to systematically test multiple configurations. We found that increased shoulder flexion, scapular abduction, elbow extension, and the placement of the ring harness near the vertebra C7 correlate with higher gripper operation efficiency, defined as the ratio of grip force to cable tension. We conclude that force transmission efficiency is closely related to body posture configuration. These results could help guide practitioners in clinical practice as well as motivate future studies in optimizing the operation of a body-powered prosthesis. Clinical relevance The results from this study suggest that clinicians ought to place the ring harness inferior and to the sound side of the vertebra prominens in order to maximize grip efficiency. The results will also help clinicians better instruct patients in body posture during prosthesis operation to minimize strain.

The African disability scooter: efficiency testing in paediatric amputees in Malawi

PubMed Central

Beckles, Verona; McCahill, Jennifer L.; Stebbins, Julie; Mkandawire, Nyengo; Church, John C. T.; Lavy, Chris

2016-01-01

Abstract Purpose: The African Disability Scooter (ADS) was developed for lower limb amputees, to improve mobility and provide access to different terrains. The aim of this study was to test the efficiency of the ADS in Africa over different terrains. Method: Eight subjects with a mean age of 12 years participated. Energy expenditure and speed were calculated over different terrains using the ADS, a prosthetic limb, and crutches. Repeated testing was completed on different days to assess learning effect. Results: Speed was significantly faster with the ADS on a level surface compared to crutch walking. This difference was maintained when using the scooter on rough terrain. Oxygen cost was halved with the scooter on level ground compared to crutch walking. There were no significant differences in oxygen consumption or heart rate. There were significant differences in oxygen cost and speed between days using the scooter over level ground, suggesting the presence of a learning effect. Conclusions: This study demonstrates that the ADS is faster and more energy efficient than crutch walking in young individuals with amputations, and should be considered as an alternative to a prosthesis where this is not available. The presence of a learning effect suggests supervision and training is required when the scooter is first issued.Implications for RehabilitationThe African Disability Scooter:is faster than crutch walking in amputees;is more energy efficient than walking with crutches;supervised use is needed when learning to use the device;is a good alternative/adjunct for mobility. PMID:25316033

A Randomized, Controlled Trial of Mirror Therapy for Upper Extremity Phantom Limb Pain in Male Amputees.

PubMed

Finn, Sacha B; Perry, Briana N; Clasing, Jay E; Walters, Lisa S; Jarzombek, Sandra L; Curran, Sean; Rouhanian, Minoo; Keszler, Mary S; Hussey-Andersen, Lindsay K; Weeks, Sharon R; Pasquina, Paul F; Tsao, Jack W

2017-01-01

Phantom limb pain (PLP) is prevalent in patients post-amputation and is difficult to treat. We assessed the efficacy of mirror therapy in relieving PLP in unilateral, upper extremity male amputees. Fifteen participants from Walter Reed and Brooke Army Medical Centers were randomly assigned to one of two groups: mirror therapy ( n  = 9) or control ( n  = 6, covered mirror or mental visualization therapy). Participants were asked to perform 15 min of their assigned therapy daily for 5 days/week for 4 weeks. The primary outcome was pain as measured using a 100-mm Visual Analog Scale. Subjects in the mirror therapy group had a significant decrease in pain scores, from a mean of 44.1 (SD = 17.0) to 27.5 (SD = 17.2) mm ( p  = 0.002). In addition, there was a significant decrease in daily time experiencing pain, from a mean of 1,022 (SD = 673) to 448 (SD = 565) minutes ( p  = 0.003). By contrast, the control group had neither diminished pain ( p  = 0.65) nor decreased overall time experiencing pain ( p  = 0.49). A pain decrement response seen by the 10th treatment session was predictive of final efficacy. These results confirm that mirror therapy is an effective therapy for PLP in unilateral, upper extremity male amputees, reducing both severity and duration of daily episodes. NCT0030144 ClinicalTrials.gov.

Sport Opportunities for Athletes with Disabilities.

ERIC Educational Resources Information Center

Journal of Physical Education, Recreation & Dance, 1984

1984-01-01

This series outlines sport opportunities for athletes with disabilities. Included are articles discussing sports for athletes with cerebral palsy, deaf athletes, blind athletes, wheelchair bound athletes, amputee athletes, as well as a discussion of the Special Olympics. (JMK)

Control and Evaluation of a Powered Transfemoral Prosthesis for Stair Ascent.

PubMed

Ledoux, Elissa D; Goldfarb, Michael

2017-07-01

This paper assesses the metabolic effort exerted by three transfemoral amputees, when using a powered knee and ankle prosthesis for stair ascent, relative to ascending stairs with passive knee and ankle prostheses. The paper describes a controller that provides step-over stair ascent behavior reflective of healthy stair ascent biomechanics, and describes its implementation in a powered prosthesis prototype. Stair ascent experiments were performed with three unilateral transfemoral amputee subjects, comparing the oxygen consumption required to ascend stairs using the powered prosthesis (with a step-over gait), relative to using their daily-use energetically passive prostheses (with a step-to gait). Results indicate on average a 24% reduction in oxygen consumption and a 30% reduction in stair ascent timewhen using the powered prosthesis, relative to when using the passive prostheses. All subjects expressed a strong preference for ascending stairs using the powered prosthesis.

Modeling the interactions between a prosthetic socket, polyurethane liners and the residual limb in transtibial amputees using non-linear finite element analysis.

PubMed

Simpson, G; Fisher, C; Wright, D K

2001-01-01

Continuing earlier studies into the relationship between the residual limb, liner and socket in transtibial amputees, we describe a geometrically accurate non-linear model simulating the donning of a liner and then a socket. The socket is rigid and rectified and the liner is a polyurethane geltype which is accurately described using non-linear (Mooney-Rivlin) material properties. The soft tissue of the residual limb is modelled as homogeneous, non-linear and hyperelastic and the bone structure within the residual limb is taken as rigid. The work gives an indication of how the stress induced by the process of donning the rigid socket is redistributed by the liner. Ultimately we hope to understand how the liner design might be modified to reduce discomfort. The ANSYS finite element code, version 5.6 is used.

Virtual prototyping of a semi-active transfemoral prosthetic leg.

PubMed

Lui, Zhen Wei; Awad, Mohammed I; Abouhossein, Alireza; Dehghani-Sanij, Abbas A; Messenger, Neil

2015-05-01

This article presents a virtual prototyping study of a semi-active lower limb prosthesis to improve the functionality of an amputee during prosthesis-environment interaction for level ground walking. Articulated ankle-foot prosthesis and a single-axis semi-active prosthetic knee with active and passive operating modes were considered. Data for level ground walking were collected using a photogrammetric method in order to develop a base-line simulation model and with the hip kinematics input to verify the proposed design. The simulated results show that the semi-active lower limb prosthesis is able to move efficiently in passive mode, and the activation time of the knee actuator can be reduced by approximately 50%. Therefore, this semi-active system has the potential to reduce the energy consumption of the actuators required during level ground walking and requires less compensation from the amputee due to lower deviation of the vertical excursion of body centre of mass. © IMechE 2015.

Illusory movement perception improves motor control for prosthetic hands

PubMed Central

Marasco, Paul D.; Hebert, Jacqueline S.; Sensinger, Jon W.; Shell, Courtney E.; Schofield, Jonathon S.; Thumser, Zachary C.; Nataraj, Raviraj; Beckler, Dylan T.; Dawson, Michael R.; Blustein, Dan H.; Gill, Satinder; Mensh, Brett D.; Granja-Vazquez, Rafael; Newcomb, Madeline D.; Carey, Jason P.; Orzell, Beth M.

2018-01-01

To effortlessly complete an intentional movement, the brain needs feedback from the body regarding the movement’s progress. This largely non-conscious kinesthetic sense helps the brain to learn relationships between motor commands and outcomes to correct movement errors. Prosthetic systems for restoring function have predominantly focused on controlling motorized joint movement. Without the kinesthetic sense, however, these devices do not become intuitively controllable. Here we report a method for endowing human amputees with a kinesthetic perception of dexterous robotic hands. Vibrating the muscles used for prosthetic control via a neural-machine interface produced the illusory perception of complex grip movements. Within minutes, three amputees integrated this kinesthetic feedback and improved movement control. Combining intent, kinesthesia, and vision instilled participants with a sense of agency over the robotic movements. This feedback approach for closed-loop control opens a pathway to seamless integration of minds and machines. PMID:29540617

Online human training of a myoelectric prosthesis controller via actor-critic reinforcement learning.

PubMed

Pilarski, Patrick M; Dawson, Michael R; Degris, Thomas; Fahimi, Farbod; Carey, Jason P; Sutton, Richard S

2011-01-01

As a contribution toward the goal of adaptable, intelligent artificial limbs, this work introduces a continuous actor-critic reinforcement learning method for optimizing the control of multi-function myoelectric devices. Using a simulated upper-arm robotic prosthesis, we demonstrate how it is possible to derive successful limb controllers from myoelectric data using only a sparse human-delivered training signal, without requiring detailed knowledge about the task domain. This reinforcement-based machine learning framework is well suited for use by both patients and clinical staff, and may be easily adapted to different application domains and the needs of individual amputees. To our knowledge, this is the first my-oelectric control approach that facilitates the online learning of new amputee-specific motions based only on a one-dimensional (scalar) feedback signal provided by the user of the prosthesis. © 2011 IEEE

Intraneural stimulation elicits discrimination of textural features by artificial fingertip in intact and amputee humans.

PubMed

Oddo, Calogero Maria; Raspopovic, Stanisa; Artoni, Fiorenzo; Mazzoni, Alberto; Spigler, Giacomo; Petrini, Francesco; Giambattistelli, Federica; Vecchio, Fabrizio; Miraglia, Francesca; Zollo, Loredana; Di Pino, Giovanni; Camboni, Domenico; Carrozza, Maria Chiara; Guglielmelli, Eugenio; Rossini, Paolo Maria; Faraguna, Ugo; Micera, Silvestro

2016-03-08

Restoration of touch after hand amputation is a desirable feature of ideal prostheses. Here, we show that texture discrimination can be artificially provided in human subjects by implementing a neuromorphic real-time mechano-neuro-transduction (MNT), which emulates to some extent the firing dynamics of SA1 cutaneous afferents. The MNT process was used to modulate the temporal pattern of electrical spikes delivered to the human median nerve via percutaneous microstimulation in four intact subjects and via implanted intrafascicular stimulation in one transradial amputee. Both approaches allowed the subjects to reliably discriminate spatial coarseness of surfaces as confirmed also by a hybrid neural model of the median nerve. Moreover, MNT-evoked EEG activity showed physiologically plausible responses that were superimposable in time and topography to the ones elicited by a natural mechanical tactile stimulation. These findings can open up novel opportunities for sensory restoration in the next generation of neuro-prosthetic hands.

Performance enhancement of epoxy based sandwich composites using multiwalled carbon nanotubes for the application of sockets in trans-femoral amputees.

PubMed

Arun, S; Kanagaraj, S

2016-06-01

A socket plays a vital role in giving the comfort to the amputees. However, the accumulation of heat inside the socket and its weight led to increase their metabolic cost. Hence, an attempt was made to increase the performance of the epoxy based sandwich composites to be used for the socket by reinforcing multiwalled carbon nanotubes (MWCNT), which was varied from 0.1 to 0.5wt%. It was homogeneously dispersed in epoxy to obtain the desired properties, where the enhancement of thermal conductivity, compressive strength and modulus of epoxy was observed to be 76.7%, 62.6% and 20.2%, respectively at 0.3wt% of MWCNT concentration beyond which the mechanical properties were found to be decreased. Hence, the epoxy, E-glass plain fabric, 2-10 layers of stockinet and 0.3wt% of MWCNT were used to prepare the sandwich composites. The flexural strength and thermal conductivity of 0.3wt% of MWCNT reinforced sandwich composites were found to be improved by 11.38±1.5% and 29.8±1.3% for the 4-10 layers and up to 10 layers of stockinet, respectively compared to unreinforced sandwich composites, which helped to reduce the weight of the socket and decrease the heat accumulation inside the socket. Thus, it is suggested to be explored for the application of socket in trans-femoral amputees to increase their comfort level by decreasing the metabolic cost. Copyright © 2015 Elsevier Ltd. All rights reserved.

Clinical and theoretical parallels between desire for limb amputation and gender identity disorder.

PubMed

Lawrence, Anne A

2006-06-01

Desire for amputation of a healthy limb has usually been regarded as a paraphilia (apotemnophilia), but some researchers propose that it may be a disorder of identity, similar to Gender Identity Disorder (GID) or transsexualism. Similarities between the desire for limb amputation and nonhomosexual male-to-female (MtF) transsexualism include profound dissatisfaction with embodiment, related paraphilias from which the conditions plausibly derive (apotemnophilia and autogynephilia), sexual arousal from simulation of the sought-after status (pretending to be an amputee and transvestism), attraction to persons with the same body type one wants to acquire, and an elevated prevalence of other paraphilic interests. K. Freund and R. Blanchard (1993) proposed that nonhomosexual MtF transsexualism represents an erotic target location error, in which men whose preferred erotic targets are women also eroticize their own feminized bodies. Desire for limb amputation may also reflect an erotic target location error, occurring in combination with an unusual erotic target preference for amputees. This model predicts that persons who desire limb amputation would almost always be attracted to amputees and would display an increased prevalence of gender identity problems, both of which have been observed. Persons who desire limb amputation and nonhomosexual MtF transsexuals often assert that their motives for wanting to change their bodies reflect issues of identity rather than sexuality, but because erotic/romantic orientations contribute significantly to identity, such distinctions may not be meaningful. Experience with nonhomosexual MtF transsexualism suggests possible directions for research and treatment for persons who desire limb amputation.

Designing and testing lightweight shoulder prostheses with hybrid actuators for movements involved in typical activities of daily living and impact absorption.

PubMed

Sekine, Masashi; Kita, Kahori; Yu, Wenwei

2015-01-01

Unlike forearm amputees, transhumeral amputees have residual stumps that are too small to provide a sufficient range of operation for their prosthetic parts to perform usual activities of daily living. Furthermore, it is difficult for small residual stumps to provide sufficient impact absorption for safe manipulation in daily living, as intact arms do. Therefore, substitution of upper limb function in transhumeral amputees requires a sufficient range of motion and sufficient viscoelasticity for shoulder prostheses under critical weight and dimension constraints. We propose the use of two different types of actuators, ie, pneumatic elastic actuators (PEAs) and servo motors. PEAs offer high power-to-weight performance and have intrinsic viscoelasticity in comparison with motors or standard industrial pneumatic cylinder actuators. However, the usefulness of PEAs in large working spaces is limited because of their short strokes. Servo motors, in contrast, can be used to achieve large ranges of motion. In this study, the relationship between the force and stroke of PEAs was investigated. The impact absorption of both types of actuators was measured using a single degree-of-freedom prototype to evaluate actuator compliance for safety purposes. Based on the fundamental properties of the actuators identified, a four degree-of-freedom robotic arm is proposed for prosthetic use. The configuration of the actuators and functional parts was designed to achieve a specified range of motion and torque calculated from the results of a simulation of typical movements performed in usual activities of daily living. Our experimental results showed that the requirements for the shoulder prostheses could be satisfied.

Case study: survey of patient satisfaction with prosthesis quality and design among below-knee prosthetic leg socket users.

PubMed

Mohd Hawari, Nurhanisah; Jawaid, Mohammad; Md Tahir, Paridah; Azmeer, Raja Ahmad

2017-11-01

The aim of this case study was to explore patient satisfaction with the quality of prosthetic leg sockets intended for persons with lower limb amputations. A qualitative study based on in-depth interviews, preceded by a questionnaire session, was carried out with patients from the Rehabilitation Center and Hospital in Malaysia. Twelve out-patient and in-patient amputees with lower limb amputations, specifically below-knee amputations, were chosen randomly. The analysis of patients' narratives aimed to identify the functional and esthetic characteristics of currently used prosthetic leg sockets and any problems related to them. The obtained results indicated that out of the 12 participants, 41.7% and 25% were satisfied and somewhat satisfied with their current prosthetic sockets. Durability and comfort were rated by the participants as the most important characteristics of prosthetic sockets, with 83.3%. As regards the esthetic appearance of the socket, 66.7% of the respondents considered that the most important feature was the material from which the socket was fabricated. Thus, we conclude that current satisfaction levels with the quality of prosthetic sockets among amputees in Malaysia are suitable, prosthesis being preferred by many amputees. The results can be used to direct future research on cosmesis and functionality of prosthetic socket design. Implications for Rehabilitation Case study will help participants to get cost effective prosthetic leg socket. Develop prosthetic leg socket comfortable as comparative to existing one. Help Malaysian government to make policy to develop local prosthetic leg socket at affordable price.

A new method to quantify liner deformation within a prosthetic socket for below knee amputees.

PubMed

Lenz, Amy L; Johnson, Katie A; Bush, Tamara Reid

2018-06-06

Many amputees who wear a leg prosthesis develop significant skin wounds on their residual limb. The exact cause of these wounds is unclear as little work has studied the interface between the prosthetic device and user. Our research objective was to develop a quantitative method for assessing displacement patterns of the gel liner during walking for patients with transtibial amputation. Using a reflective marker system and a custom clear socket, evaluations were conducted with a clear transparent test socket mounted over a plaster limb model and a deformable limb model. Distances between markers placed on the limb were measured with a digital caliper and then compared with data from the motion capture system. Additionally, the rigid plaster set-up was moved in the capture volume to simulate walking and evaluate if inter-marker distances changed in comparison to static data. Dynamic displacement trials were then collected to measure changes in inter-marker distance due to vertical elongation of the gel liner. Static and dynamic inter-marker distances within day and across days confirmed the ability to accurately capture displacements using this new approach. These results encourage this novel method to be applied to a sample of amputee patients during walking to assess displacements and the distribution of the liner deformation within the socket. The ability to capture changes in deformation of the gel liner will provide new data that will enable clinicians and researchers to improve design and fit of the prosthesis so the incidence of pressure ulcers can be reduced. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cross-cultural variation in preference for replantation or revision amputation: Societal and surgeon views.

PubMed

Maroukis, Brianna L; Shauver, Melissa J; Nishizuka, Takanobu; Hirata, Hitoshi; Chung, Kevin C

2016-04-01

Treatment decisions after an injury like finger amputation are made based on injury and patient factors. However, decisions can also be influenced by provider and patient preferences. We compared hand surgeon and societal preferences and attitudes regarding finger amputation treatment in Japan and the US. We performed a cross-sectional survey with subjects derived from large tertiary care academic institutions in the US and Japan. We secured 100% participation of American hand surgeon members of the Finger Replantation and Amputation Multicenter Study and presenting hand surgeons at the 32nd Annual meeting of the Central Japanese Society for Surgery of the Hand. Societal preferences were gathered from volunteers at the 2 universities in the US and Japan. There were no significant differences in estimations of function, sensation, or appearance after replantation; American and Japanese societal participants preferred replantation compared to surgeons, although this was more pronounced in Japan. The Japanese society displayed more negative attitudes toward finger amputees than did Japanese surgeons. American respondents anticipated more public stigmatisation of amputees than did American surgeons. Societal preference for replantation was not caused by inflated expectations of outcomes after replantation. Japanese societal preference was likely driven by negative views of finger amputees. American society noted no decrease in physical health after amputation, but did note a quality of life decrease attributed to public stigmatisation. Japanese society and surgeons had a stronger preference for replantation than American society and surgeons, possibly attributed to cultural differences. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prosthesis Control with an Implantable Multichannel Wireless Electromyography System for High-Level Amputees: A Large-Animal Study.

PubMed

Bergmeister, Konstantin D; Hader, Marie; Lewis, Soeren; Russold, Michael-Friedrich; Schiestl, Martina; Manzano-Szalai, Krisztina; Roche, Aidan D; Salminger, Stefan; Dietl, Hans; Aszmann, Oskar C

2016-01-01

Myoelectric prostheses lack a strong human-machine interface, leading to high abandonment rates in upper limb amputees. Implantable wireless electromyography systems improve control by recording signals directly from muscle, compared with surface electromyography. These devices do not exist for high amputation levels. In this article, the authors present an implantable wireless electromyography system for these scenarios tested in Merino sheep for 4 months. In a pilot trial, the electrodes were implanted in the hind limbs of 24 Sprague-Dawley rats. After 8 or 12 weeks, impedance and histocompatibility were assessed. In the main trial, the system was tested in four Merino sheep for 4 months. Impedance of the electrodes was analyzed in two animals. Electromyographic data were analyzed in two freely moving animals repeatedly during forward and backward gait. Device implantation was successful in all 28 animals. Histologic evaluation showed a tight encapsulation after 8 weeks of 78.2 ± 26.5 µm subcutaneously and 92.9 ± 31.3 µm on the muscular side. Electromyographic recordings show a distinct activation pattern of the triceps, brachialis, and latissimus dorsi muscles, with a low signal-to-noise ratio, representing specific patterns of agonist and antagonist activation. Average electrode impedance decreased over the whole frequency range, indicating an improved electrode-tissue interface during the implantation. All measurements taken over the 4 months of observation used identical settings and showed similar recordings despite changing environmental factors. This study shows the implantation of this electromyography device as a promising alternative to surface electromyography, providing a potentially powerful wireless interface for high-level amputees.

Real-time, ultrasound-based control of a virtual hand by a trans-radial amputee.

PubMed

Baker, Clayton A; Akhlaghi, Nima; Rangwala, Huzefa; Kosecka, Jana; Sikdar, Siddhartha

2016-08-01

Advancements in multiarticulate upper-limb prosthetics have outpaced the development of intuitive, non-invasive control mechanisms for implementing them. Surface electromyography is currently the most popular non-invasive control method, but presents a number of drawbacks including poor deep-muscle specificity. Previous research established the viability of ultrasound imaging as an alternative means of decoding movement intent, and demonstrated the ability to distinguish between complex grasps in able-bodied subjects via imaging of the anterior forearm musculature. In order to translate this work to clinical viability, able-bodied testing is insufficient. Amputation-induced changes in muscular geometry, dynamics, and imaging characteristics are all likely to influence the effectiveness of our existing techniques. In this work, we conducted preliminary trials with a transradial amputee participant to assess these effects, and potentially elucidate necessary refinements to our approach. Two trials were performed, the first using a set of three motion types, and the second using four. After a brief training period in each trial, the participant was able to control a virtual prosthetic hand in real-time; attempted grasps were successfully classified with a rate of 77% in trial 1, and 71% in trial 2. While the results are sub-optimal compared to our previous able-bodied testing, they are a promising step forward. More importantly, the data collected during these trials can provide valuable information for refining our image processing methods, especially via comparison to previously acquired data from able-bodied individuals. Ultimately, further work with amputees is a necessity for translation towards clinical application.

Double nerve intraneural interface implant on a human amputee for robotic hand control.

PubMed

Rossini, Paolo M; Micera, Silvestro; Benvenuto, Antonella; Carpaneto, Jacopo; Cavallo, Giuseppe; Citi, Luca; Cipriani, Christian; Denaro, Luca; Denaro, Vincenzo; Di Pino, Giovanni; Ferreri, Florinda; Guglielmelli, Eugenio; Hoffmann, Klaus-Peter; Raspopovic, Stanisa; Rigosa, Jacopo; Rossini, Luca; Tombini, Mario; Dario, Paolo

2010-05-01

The principle underlying this project is that, despite nervous reorganization following upper limb amputation, original pathways and CNS relays partially maintain their function and can be exploited for interfacing prostheses. Aim of this study is to evaluate a novel peripheral intraneural multielectrode for multi-movement prosthesis control and for sensory feed-back, while assessing cortical reorganization following the re-acquired stream of data. Four intrafascicular longitudinal flexible multielectrodes (tf-LIFE4) were implanted in the median and ulnar nerves of an amputee; they reliably recorded output signals for 4 weeks. Artificial intelligence classifiers were used off-line to analyse LIFE signals recorded during three distinct hand movements under voluntary order. Real-time control of motor output was achieved for the three actions. When applied off-line artificial intelligence reached >85% real-time correct classification of trials. Moreover, different types of current stimulation were determined to allow reproducible and localized hand/fingers sensations. Cortical organization was observed via TMS in parallel with partial resolution of symptoms due to the phantom-limb syndrome (PLS). tf-LIFE4s recorded output signals in human nerves for 4 weeks, though the efficacy of sensory stimulation decayed after 10 days. Recording from a number of fibres permitted a high percentage of distinct actions to be classified correctly. Reversal of plastic changes and alleviation of PLS represent corollary findings of potential therapeutic benefit. This study represents a breakthrough in robotic hand use in amputees. Copyright 2010 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Quadrupedal gaits in hexapod animals - inter-leg coordination in free-walking adult stick insects.

PubMed

Grabowska, Martyna; Godlewska, Elzbieta; Schmidt, Joachim; Daun-Gruhn, Silvia

2012-12-15

The analysis of inter-leg coordination in insect walking is generally a study of six-legged locomotion. For decades, the stick insect Carausius morosus has been instrumental for unravelling the rules and mechanisms that control leg coordination in hexapeds. We analysed inter-leg coordination in C. morosus that freely walked on straight paths on plane surfaces with different slopes. Consecutive 1.7 s sections were assigned inter-leg coordination patterns (which we call gaits) based on footfall patterns. Regular gaits, i.e. wave, tetrapod or tripod gaits, occurred in different proportions depending on surface slopes. Tetrapod gaits were observed most frequently, wave gaits only occurred on 90 deg inclining slopes and tripod gaits occurred most often on 15 deg declining slopes, i.e. in 40% of the sections. Depending on the slope, 36-66% of the sections were assigned irregular gaits. Irregular gaits were mostly due to multiple stepping by the front legs, which is perhaps probing behaviour, not phase coupled to the middle legs' cycles. In irregular gaits, middle leg and hindleg coordination was regular, related to quadrupedal walk and wave gaits. Apparently, front legs uncouple from and couple to the walking system without compromising middle leg and hindleg coordination. In front leg amputees, the remaining legs were strictly coordinated. In hindleg and middle leg amputees, the front legs continued multiple stepping. The coordination of middle leg amputees was maladapted, with front legs and hindlegs performing multiple steps or ipsilateral legs being in simultaneous swing. Thus, afferent information from middle legs might be necessary for a regular hindleg stepping pattern.

First results concerning the safety, walking, and satisfaction with an innovative, microprocessor-controlled four-axes prosthetic foot.

PubMed

Hahn, Andreas; Sreckovic, Ivana; Reiter, Sebastian; Mileusnic, Milana

2018-06-01

The microprocessor-controlled foot Meridium is a prosthetic component with adjustable stance-phase characteristics. To investigate subjects' and prosthetists' perception of safety, walking, and satisfaction during first routine fittings. Multicenter, prospective, observational cohort study. Data regarding demographics, fitting process, safety, daily life activities, and satisfaction were obtained through questionnaires. The follow-up period was 7 months. In all, 89% of 70 users were satisfactorily fitted within the first two visits. Compared to previous feet, users reported improvements in walking on level ground (54% of subjects), uneven ground (82%), ascending (97%), and descending ramps (91%). More than 45% of the users perceived an improvement in safety and stability while standing and walking. No difference was observed in concentration, exertion, and pain. Overall user satisfaction with Meridium was 50% and the foot was preferred by 40% of users. Amputation level, age and mobility grade did not influence subjects' preference. Prosthetists recommended Meridium for 59% of subjects. A correlation analysis revealed that transfemoral amputees fitted with Genium and/or having a long residual limb strongly preferred Meridium ( p < 0.05). Meridium was appreciated by amputees with a preference for natural walking and requirement to safely and comfortably negotiate uneven terrain and slopes. Clinical relevance Amputees preferring Meridium perceive benefits with safe, comfortable, and natural walking. While the perception of benefits regarding the negotiation of uneven terrain and slopes is very high, the correlation to product preference is moderate. Individual assessment and trial fitting might be essential to identify patients who benefit greatly.

Functional added value of microprocessor-controlled knee joints in daily life performance of Medicare Functional Classification Level-2 amputees.

PubMed

Theeven, Patrick; Hemmen, Bea; Rings, Frans; Meys, Guido; Brink, Peter; Smeets, Rob; Seelen, Henk

2011-10-01

To assess the effects of using a microprocessor-controlled prosthetic knee joint on the functional performance of activities of daily living in persons with an above-knee leg amputation. To assess the effects of using a microprocessor-controlled prosthetic knee joint on the functional performance of activities of daily living in persons with an above-knee leg amputation. Randomised cross-over trial. Forty-one persons with unilateral above-knee or knee disarticulation limb loss, classified as Medicare Functional Classification Level-2 (MFCL-2). Participants were measured in 3 conditions, i.e. using a mechanically controlled knee joint and two types of microprocessor-controlled prosthetic knee joints. Functional performance level was assessed using a test in which participants performed 17 simulated activities of daily living (Assessment of Daily Activity Performance in Transfemoral amputees test). Performance time was measured and self-perceived level of difficulty was scored on a visual analogue scale for each activity. High levels of within-group variability in functional performance obscured detection of any effects of using a microprocessor-controlled prosthetic knee joint. Data analysis after stratification of the participants into 3 subgroups, i.e. participants with a "low", "intermediate" and "high" functional mobility level, showed that the two higher functional subgroups performed significantly faster using microprocessor-controlled prosthetic knee joints. MFCL-2 amputees constitute a heterogeneous patient group with large variation in functional performance levels. A substantial part of this group seems to benefit from using a microprocessor-controlled prosthetic knee joint when performing activities of daily living.

Use of probabilistic weights to enhance linear regression myoelectric control

NASA Astrophysics Data System (ADS)

Smith, Lauren H.; Kuiken, Todd A.; Hargrove, Levi J.

2015-12-01

Objective. Clinically available prostheses for transradial amputees do not allow simultaneous myoelectric control of degrees of freedom (DOFs). Linear regression methods can provide simultaneous myoelectric control, but frequently also result in difficulty with isolating individual DOFs when desired. This study evaluated the potential of using probabilistic estimates of categories of gross prosthesis movement, which are commonly used in classification-based myoelectric control, to enhance linear regression myoelectric control. Approach. Gaussian models were fit to electromyogram (EMG) feature distributions for three movement classes at each DOF (no movement, or movement in either direction) and used to weight the output of linear regression models by the probability that the user intended the movement. Eight able-bodied and two transradial amputee subjects worked in a virtual Fitts’ law task to evaluate differences in controllability between linear regression and probability-weighted regression for an intramuscular EMG-based three-DOF wrist and hand system. Main results. Real-time and offline analyses in able-bodied subjects demonstrated that probability weighting improved performance during single-DOF tasks (p < 0.05) by preventing extraneous movement at additional DOFs. Similar results were seen in experiments with two transradial amputees. Though goodness-of-fit evaluations suggested that the EMG feature distributions showed some deviations from the Gaussian, equal-covariance assumptions used in this experiment, the assumptions were sufficiently met to provide improved performance compared to linear regression control. Significance. Use of probability weights can improve the ability to isolate individual during linear regression myoelectric control, while maintaining the ability to simultaneously control multiple DOFs.

Paré and prosthetics: the early history of artificial limbs.

PubMed

Thurston, Alan J

2007-12-01

There is evidence for the use of prostheses from the times of the ancient Egyptians. Prostheses were developed for function, cosmetic appearance and a psycho-spiritual sense of wholeness. Amputation was often feared more than death in some cultures. It was believed that it not only affected the amputee on earth, but also in the afterlife. The ablated limbs were buried and then disinterred and reburied at the time of the amputee's death so the amputee could be whole for eternal life. One of the earliest examples comes from the 18th dynasty of ancient Egypt in the reign of Amenhotep II in the fifteenth century bc. A mummy in the Cairo Museum has clearly had the great toe of the right foot amputated and replaced with a prosthesis manufactured from leather and wood. The first true rehabilitation aids that could be recognized as prostheses were made during the civilizations of Greece and Rome. During the Dark Ages prostheses for battle and hiding deformity were heavy, crude devices made of available materials - wood, metal and leather. Such were the materials available to Ambroise Paré who invented both upper-limb and lower-limb prostheses. His 'Le Petit Lorrain', a mechanical hand operated by catches and springs, was worn by a French Army captain in battle. Subsequent refinements in medicine, surgery and prosthetic science greatly improved amputation surgery and the function of prostheses. What began as a modified crutch with a wooden or leather cup and progressed through many metamorphoses has now developed into a highly sophisticated prosthetic limb made of space-age materials.

Body image and self-esteem in lower-limb amputees.

PubMed

Holzer, Lukas A; Sevelda, Florian; Fraberger, Georg; Bluder, Olivia; Kickinger, Wolfgang; Holzer, Gerold

2014-01-01

Limb amputation is often an inevitable procedure in the advanced condition of various diseases and poses a dramatic impact on a patient's life. The aim of the present study is to analyze the impact of lower-limb amputations on aesthetic factors such as body image and self-esteem as well as quality of life (QoL). 298 patients (149 uni- or bilateral lower-limb amputees and 149 controls) were included in this cross-sectional study in three centers. Demographic data was collected and patients received a 118-item questionnaire including the Multidimensional Body-Self Relations Questionnaire (MBSRQ), the Rosenberg Self-esteem (RSE) scale and the SF-36 Health Survey (QoL). ANOVA and student's t-test were used for statistical analysis. Unilateral lower-limb amputees showed a significant lower MBSRQ score of 3.07±0.54 compared with 3.41±0.34 in controls (p<0.001) and a lower score in the RSE compared to controls (21.63±4.72 vs. 21.46±5.86). However, differences were not statistically significant (p = 0.36). Patients with phantom pain sensation had a significantly reduced RSE (p = 0.01). The SF-36 health survey was significantly lower in patients with lower-limb amputation compared to controls (42.17±14.47 vs. 64.05±12.39) (p<0.001). This study showed that lower-limb amputations significantly influence patients' body image and QoL. Self-esteem seems to be an independent aspect, which is not affected by lower-limb amputation. However, self-esteem is influenced significantly by phantom pain sensation.

Prosthetic Hand Lifts Heavy Loads

NASA Technical Reports Server (NTRS)

Carden, James R.; Norton, William; Belcher, Jewell G.; Vest, Thomas W.

1991-01-01

Prosthetic hand designed to enable amputee to lift diverse heavy objects like rocks and logs. Has simple serrated end effector with no moving parts. Prosthesis held on forearm by system of flexible straps. Features include ruggedness, simplicity, and relatively low cost.

Assessing physical function in adult acquired major upper-limb amputees by combining the Disabilities of the Arm, Shoulder and Hand (DASH) Outcome Questionnaire and clinical examination.

PubMed

Ostlie, Kristin; Franklin, Rosemary J; Skjeldal, Ola H; Skrondal, Anders; Magnus, Per

2011-10-01

To describe physical function in adult acquired major upper-limb amputees (ULAs) by combining self-assessed arm function and physical measures obtained by clinical examinations; to estimate associations between background factors and self-assessed arm function in ULAs; and to assess whether clinical examination findings may be used to detect reduced arm function in unilateral ULAs. postal questionnaires and clinical examinations. Norwegian ULA population. Clinical examinations performed at 3 clinics. Questionnaires: population-based sample (n=224; 57.4% response rate). Clinical examinations: combined referred sample and convenience sample of questionnaire responders (n=70; 83.3% of those invited). SURVEY inclusion criteria: adult acquired major upper-limb amputation, resident in Norway, mastering of spoken and written Norwegian. Not applicable. The Disabilities of the Arm, Shoulder and Hand (DASH) Outcome Questionnaire, and clinical examination of joint motion and muscle strength with and without prostheses. Mean DASH score was 22.7 (95% confidence interval [CI], 20.3-25.0); in bilateral amputees, 35.7 (95% CI, 23.0-48.4); and in unilateral amputees, 22.1 (95% CI, 19.8-24.5). A lower unilateral DASH score (better function) was associated with paid employment (vs not in paid employment: adjusted regression coefficient [aB]=-5.40, P=.033; vs students: aB=-13.88, P=.022), increasing postamputation time (aB=-.27, P=.001), and Norwegian ethnicity (aB=-14.45, P<.001). At clinical examination, we found a high frequency of impaired neck mobility and varying frequencies of impaired joint motion and strength at the shoulder, elbow, and forearm level. Prosthesis wear was associated with impaired joint motion in all upper-limb joints (P<.006) and with reduced shoulder abduction strength (P=.002). Impaired without-prosthesis joint motion in shoulder flexion (ipsilateral: aB=12.19, P=.001) and shoulder abduction (ipsilateral: aB=12.01, P=.005; contralateral: aB=28.82, P=.004) was associated with increased DASH scores. Upper-limb loss clearly affects physical function. DASH score limitation profiles may be useful in individual clinical assessments. Targeted clinical examination may indicate patients with extra rehabilitational needs. Such examinations may be of special importance in relation to prosthesis function. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

A proportional control scheme for high density force myography.

PubMed

Belyea, Alexander T; Englehart, Kevin B; Scheme, Erik J

2018-08-01

Force myography (FMG) has been shown to be a potentially higher accuracy alternative to electromyography for pattern recognition based prosthetic control. Classification accuracy, however, is just one factor that affects the usability of a control system. Others, like the ability to start and stop, to coordinate dynamic movements, and to control the velocity of the device through some proportional control scheme can be of equal importance. To impart effective fine control using FMG-based pattern recognition, it is important that a method of controlling the velocity of each motion be developed. In this work force myography data were collected from 14 able bodied participants and one amputee participant as they performed a set of wrist and hand motions. The offline proportional control performance of a standard mean signal amplitude approach and a proposed regression-based alternative was compared. The impact of providing feedback during training, as well as the use of constrained or unconstrained hand and wrist contractions, were also evaluated. It is shown that the commonly used mean of rectified channel amplitudes approach commonly employed with electromyography does not translate to force myography. The proposed class-based regression proportional control approach is shown significantly outperform this standard approach (ρ  <  0.001), yielding a R 2 correlation coefficients of 0.837 and 0.830 for constrained and unconstrained forearm contractions, respectively for able bodied participants. No significant difference (ρ  =  0.693) was found in R 2 performance when feedback was provided during training or not. The amputee subject achieved a classification accuracy of 83.4%  ±  3.47% demonstrating the ability to distinguish contractions well with FMG. In proportional control the amputee participant achieved an R 2 of of 0.375 for regression based proportional control during unconstrained contractions. This is lower than the unconstrained case for able-bodied subjects for this particular amputee, possibly due to difficultly in visualizing contraction level modulation without feedback. This may be remedied in the use of a prosthetic limb that would provide real-time feedback in the form of device speed. A novel class-specific regression-based approach is proposed for multi-class control is described and shown to provide an effective means of providing FMG-based proportional control.

The effects of prosthetic foot type and visual alteration on postural steadiness in below-knee amputees

PubMed Central

2014-01-01

Background Achieving independent upright posture has known to be one of the main goals in rehabilitation following lower limb amputation. The purpose of this study was to compare postural steadiness of below knee amputees with visual alterations while wearing three different prosthetic feet. Methods Ten male below-knee amputees were instructed to stand quietly on the Biodex® balance platform while wearing solid ankle cushion heel (SACH), single axis (SA) and energy storage and release (ESAR) prosthetic foot under different visual input conditions (eyes-opened and eyes-closed). The overall stability index (OSI), anterior- posterior stability index (APSI), and medial-lateral stability index (MLSI) were computed. Perceived balance assessment of each foot was evaluated using Activities-specific Balance Confidence (ABC) score. Results The findings highlights that SACH showed lowest overall stability index (indicating less body sway) during eyes-opened (OSI: SACH = 1.09, SA = 1.58, ESAR = 1.59) and SA showed lowest overall stability index during eyes-closed (OSI: SACH = 2.52, SA = 2.30, ESAR = 2.76) condition. However, overall stability indexes between foot types did not differ significantly during eyes-opened or eyes-closed (p = 0.651). There was a trend of instability which occurred more in medial-lateral compared to anterior-posterior direction for all foot types, with significant result in ESAR foot(eyes-opened: MLSI = 1.59, APSI = 0.65, p = 0.034; eyes-closed: MLSI = 2.76, APSI = 1.80, p = 0.017, respectively). When comparing between visual conditions, stability score was significantly higher during eyes-closed compared to eyes-opened situations for SACH and ESAR foot (eyes-closed vs opened; SACH OSI: 3.43 vs 1.71, p = 0.018 and MLSI: 3.43 vs 1.71, p = 0.018; ESAR OSI: 3.58 vs 1.86, p = 0.043 and APSI: 1.80 vs 0.65, p = 0.027). Conclusions The results of this study suggested postural steadiness in below-knee amputees was not affected by the types of prosthetic foot during quiet upright standing, but was significantly affected when visual cues was absent. PMID:24597518

Outdoor dynamic subject-specific evaluation of internal stresses in the residual limb: hydraulic energy-stored prosthetic foot compared to conventional energy-stored prosthetic feet.

PubMed

Portnoy, Sigal; Kristal, Anat; Gefen, Amit; Siev-Ner, Itzhak

2012-01-01

The prosthetic foot plays an important role in propelling, breaking, balancing and supporting body loads while the amputee ambulates on different grounds. It is therefore important to quantify the effect of the prosthetic foot mechanism on biomechanical parameters, in order to prevent pressure ulcers and deep tissue injury. Our aim was to monitor the internal stresses in the residuum of transtibial amputation (TTA) prosthetic-users ambulating on different terrains, which the amputees encounter during their daily activities, i.e. paved floor, grass, ascending and descending stairs and slope. We specifically aimed to compare between the internal stresses in the TTA residuum of amputees ambulating with a novel hydraulic prosthetic foot compared to conventional energy storage and return (ESR) prosthetic feet. Monitoring of internal stresses was accomplished using a portable subject-specific real-time internal stress monitor. We found significant decrease (p<0.01) in peak internal stresses and in the loading rate of the amputated limb, while walking with the hydraulic foot, compared to walking with ESR feet. The loading rate calculated while ambulating with the hydraulic foot was at least three times lower than the loading rate calculated while ambulating with the ESR foot. Although the average decrease in internal stresses was ≈ 2-fold larger when replacing single-toe ESR feet with the hydraulic foot than when replacing split-toed ESR feet with the hydraulic foot, the differences were statistically insignificant. Our findings suggest that using a hydraulic prosthetic foot may protect the distal tibial end of the TTA residuum from high stresses, therefore preventing pressure-related injury and pain. Copyright © 2011 Elsevier B.V. All rights reserved.

Upper-arm anthropometry: an alternative indicator of nutritional health to body mass index in unilateral lower-extremity amputees?

PubMed

Miller, Michelle; Wong, Wing Ki; Wu, Jing; Cavenett, Sally; Daniels, Lynne; Crotty, Maria

2008-10-01

To evaluate the utility of body mass index (BMI) and corrected-arm-muscle area (CAMA) as measures of nutritional health for lower-limb amputees attending prosthetics clinics. Cross-sectional study. Prosthetics clinic in Australia. Unilateral lower-extremity amputees (N=58; age range, 21-91y; 37 transtibial, 21 transfemoral) attending a regional prosthetics clinic between May and November 2003. Not applicable. Weight (without prosthesis), corrected and uncorrected for the amputated limb was used with height estimated from knee height to calculate corrected BMI (cBMI) and uncorrected BMI (uBMI). CAMA was calculated using the mean of triplicate mid-upper-arm circumference (MUAC) and triceps skinfold thickness (TST) measurements. The Mini Nutritional Assessment (MNA) and Assessment of Quality of Life were administered according to recommended protocols. The Pearson correlation was used to determine the strength and significance of associations between variables, and bivariate regression analyses were performed to determine whether an association existed between the nutritional variables (BMI, CAMA, MNA) and quality of life (QOL). There were no statistically significant differences in the measures of nutritional health according to site (transtibial, transfemoral) of amputation. MUAC, TST, and CAMA all showed moderate to high positive correlations (r range, .541-.782) with both cBMI and uBMI. The strength of the relationship between the MNA and cBMI/uBMI was weaker (r=.383, r=.380, respectively) but remained positive and statistically significant (P=.003). QOL was not associated with cBMI or uBMI but was related to CAMA (beta=-.132; P=.030) and MNA (beta=-.561; P=.017). For persons with unilateral lower-extremity amputation, measurement of upper-arm anthropometry may be a more useful indicator of nutritional health and its consequences than BMI.

Impact of pain in vertebral column on activities of daily living in the Iranian amputees with bilateral lower limb amputation.

PubMed

Ashraf, Alireza; Shojaee, Hadi; Mousavi, Batool; Masoumi, Mehdi; Rezaei, Noushin; Azema, Hasan; Soroush, Mohammadreza

2012-01-01

To determine the impact of pain in the vertebral column on the activities of daily living (ADL) level of war victims with bilateral lower limb amputation. All the war-related bilateral lower limb amputees were invited. More than half of them (n = 335) participated and underwent a thorough assessment after giving informed consent. The majority of the participants were male (97.6%). Their mean age was 42 years and 97.6% of them were married. The most common causes of injury leading to amputation were shells of artillery and mortar (56.7%). The most common level of amputation was bilateral transtibial (37.6%) and 64% were wearing the prosthesis of both sides. The most ADL dependency were transfer activities (27.8%) and bathing (23.3%) and the most independent functioning was eating (97.6%). Upper cervical vertebral pain was associated with dependency in the bowel and bladder management and dressing (p < 0.03 and p < 0.04, respectively). Pain in the lower cervical vertebrae was associated with dependency in toileting and dressing (p < 0.01 and p < 0.01, respectively). There were significant relationships between pain in the thoracic vertebrae and dependency in bathing, transfer activities and toileting (p < 0.02, p < 0.003 and p < 0.03, respectively). Pain in the lumbosacral region had a relationship with the level of amputation, transfer activities and toileting (p < 0.006, p < 0.03 and p < 0.05, respectively). Vertebral pain in bilateral lower limb amputees, especially lumbosacral pain, was accompanied with higher dependency in ADL. Therefore, a multidisciplinary approach to the management of pain is required to minimize disability and maximize functioning.

Biomechanics of ramp descent in unilateral trans-tibial amputees: Comparison of a microprocessor controlled foot with conventional ankle-foot mechanisms.

PubMed

Struchkov, Vasily; Buckley, John G

2016-02-01

Walking down slopes and/or over uneven terrain is problematic for unilateral trans-tibial amputees. Accordingly, 'ankle' devices have been added to some dynamic-response feet. This study determined whether use of a microprocessor controlled passive-articulating hydraulic ankle-foot device improved the gait biomechanics of ramp descent in comparison to conventional ankle-foot mechanisms. Nine active unilateral trans-tibial amputees repeatedly walked down a 5° ramp, using a hydraulic ankle-foot with microprocessor active or inactive or using a comparable foot with rubber ball-joint (elastic) 'ankle' device. When inactive the hydraulic unit's resistances were those deemed to be optimum for level-ground walking, and when active, the plantar- and dorsi-flexion resistances switched to a ramp-descent mode. Residual limb kinematics, joints moments/powers and prosthetic foot power absorption/return were compared across ankle types using ANOVA. Foot-flat was attained fastest with the elastic foot and second fastest with the active hydraulic foot (P<0.001). Prosthetic shank single-support mean rotation velocity (p =0.006), and the flexion (P<0.001) and negative work done at the residual knee (P=0.08) were reduced, and negative work done by the ankle-foot increased (P<0.001) when using the active hydraulic compared to the other two ankle types. The greater negative 'ankle' work done when using the active hydraulic compared to other two ankle types, explains why there was a corresponding reduction in flexion and negative work at the residual knee. These findings suggest that use of a microprocessor controlled hydraulic foot will reduce the biomechanical compensations used to walk down slopes. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

The comparison of transfemoral amputees using mechanical and microprocessor- controlled prosthetic knee under different walking speeds: A randomized cross-over trial.

PubMed

Cao, Wujing; Yu, Hongliu; Zhao, Weiliang; Meng, Qiaoling; Chen, Wenming

2018-04-20

The microprocessor-controlled prosthetic knees have been introduced to transfemoral amputees due to advances in biomedical engineering. A body of scientific literature has shown that the microprocessor-controlled prosthetic knees improve the gait and functional abilities of persons with transfemoral amputation. The aim of this study was to propose a new microprocessor-controlled prosthetic knee (MPK) and compare it with non-microprocessor-controlled prosthetic knees (NMPKs) under different walking speeds. The microprocessor-controlled prosthetic knee (i-KNEE) with hydraulic damper was developed. The comfortable self-selected walking speeds of 12 subjects with i-KNEE and NMPK were obtained. The maximum swing flexion knee angle and gait symmetry were compared in i-KNEE and NMPK condition. The comfortable self-selected walking speeds of some subjects were higher with i-KNEE while some were not. There was no significant difference in comfortable self-selected walking speed between the i-KNEE and the NMPK condition (P= 0.138). The peak prosthetic knee flexion during swing in the i-KNEE condition was between sixty and seventy degree under any walking speed. In the NMPK condition, the maximum swing flexion knee angle changed significantly. And it increased with walking speed. There is no significant difference in knee kinematic symmetry when the subjects wear the i-KNEE or NMPK. The results of this study indicated that the new microprocessor-controlled prosthetic knee was suitable for transfemoral amputees. The maximum swing flexion knee angle under different walking speeds showed different properties in the NMPK and i-KNEE condition. The i-KNEE was more adaptive to speed changes. There was little difference of comfortable self-selected walking speed between i-KNEE and NMPK condition.

Improved prosthetic hand control with concurrent use of myoelectric and inertial measurements.

PubMed

Krasoulis, Agamemnon; Kyranou, Iris; Erden, Mustapha Suphi; Nazarpour, Kianoush; Vijayakumar, Sethu

2017-07-11

Myoelectric pattern recognition systems can decode movement intention to drive upper-limb prostheses. Despite recent advances in academic research, the commercial adoption of such systems remains low. This limitation is mainly due to the lack of classification robustness and a simultaneous requirement for a large number of electromyogram (EMG) electrodes. We propose to address these two issues by using a multi-modal approach which combines surface electromyography (sEMG) with inertial measurements (IMs) and an appropriate training data collection paradigm. We demonstrate that this can significantly improve classification performance as compared to conventional techniques exclusively based on sEMG signals. We collected and analyzed a large dataset comprising recordings with 20 able-bodied and two amputee participants executing 40 movements. Additionally, we conducted a novel real-time prosthetic hand control experiment with 11 able-bodied subjects and an amputee by using a state-of-the-art commercial prosthetic hand. A systematic performance comparison was carried out to investigate the potential benefit of incorporating IMs in prosthetic hand control. The inclusion of IM data improved performance significantly, by increasing classification accuracy (CA) in the offline analysis and improving completion rates (CRs) in the real-time experiment. Our findings were consistent across able-bodied and amputee subjects. Integrating the sEMG electrodes and IM sensors within a single sensor package enabled us to achieve high-level performance by using on average 4-6 sensors. The results from our experiments suggest that IMs can form an excellent complimentary source signal for upper-limb myoelectric prostheses. We trust that multi-modal control solutions have the potential of improving the usability of upper-extremity prostheses in real-life applications.

Transcranial direct current stimulation versus user training on improving online myoelectric control for amputees

NASA Astrophysics Data System (ADS)

Pan, Lizhi; Zhang, Dingguo; Jiang, Ning; Sheng, Xinjun; Zhu, Xiangyang

2017-08-01

Objective. Transcranial direct current stimulation (tDCS) and user training (UT) are two types of methods to improve myoelectric control performance for amputees. In this study, we compared the independent effect between tDCS and UT, and investigated the combined effect of tDCS and UT. Approach. An online paradigm of simultaneous and proportional control (SPC) based on electromyography (EMG) was adopted. The proposed experiments were conducted on six naïve unilateral trans-radial amputees. The subjects each received three types of 20 min interventions: active tDCS with motor training (tDCS  +  UT), active tDCS with quiet sitting (tDCS), and sham tDCS with motor training (UT). The interventions were applied at one week intervals in a randomized order. The subjects performed online control of a feedback arrow with two degrees of freedom (DoFs) to accomplish target reaching motor tasks in pre-sessions and post-sessions. We compared the performance, measured by completion rate, completion time, and efficiency coefficient, between pre-sessions and post-sessions. Main results. The results showed that the intervention tDCS  +  UT and tDCS significantly improved the online SPC performance (i.e. improved the completion rate; reduced the completion time; and improved the efficiency coefficient), while intervention UT did not significantly change the performance. The results also showed that the online SPC performance after intervention tDCS  +  UT and tDCS was not significantly different, but both were significantly better than that after intervention UT. Significance. tDCS could be an effective intervention to improve the online SPC performance in a short time.

A comparison between the dimensions of positive transtibial residual limb molds prepared by air pressure casting and weight-bearing casting methods.

PubMed

Hajiaghaei, Behnam; Ebrahimi, Ismail; Kamyab, Mojtaba; Saeedi, Hassan; Jalali, Maryam

2016-01-01

Creating a socket with proper fit is an important factor to ensure the comfort and control of prosthetic devices. Several techniques are commonly used to cast transtibial stumps but their effect on stump shape deformation is not well understood. This study compares the dimensions, circumferences and volumes of the positive casts and also the socket comfort between two casting methods. Our hypothesis was that the casts prepared by air pressure method have less volume and are more comfortable than those prepared by weight bearing method. Fifteen transtibial unilateral amputees participated in the study. Two weight bearing and air pressure casting methods were utilized for their residual limbs. The diameters and circumferences of various areas of the residual limbs and positive casts were compared. The volumes of two types of casts were measured by a volumeter and compared. Visual Analogue Scale (VAS) was used to measure the sockets fit comfort. Circumferences at 10 and 15 cm below the patella on the casts were significantly smaller in air pressure casting method compared to the weight bearing method (p=0.00 and 0.01 respectively). The volume of the cast in air pressure method was lower than that of the weight bearing method (p=0.006). The amputees found the fit of the sockets prepared by air pressure method more comfortable than the weight bearing sockets (p=0.015). The air pressure casting reduced the circumferences of the distal portion of residual limbs which has more soft tissue and because of its snug fit it provided more comfort for amputees, according to the VAS measurements.

The Role of the Environment in Eliciting Phantom-Like Sensations in Non-Amputees

PubMed Central

Lewis, Elizabeth; Lloyd, Donna M.; Farrell, Martin J.

2013-01-01

Following the amputation of a limb, many amputees report that they can still vividly perceive its presence despite conscious knowledge that it is not physically there. However, our ability to probe the mental representation of this experience is limited by the intractable and often distressing pain associated with amputation. Here, we present a method for eliciting phantom-like experiences in non-amputees using a variation of the rubber hand illusion in which a finger has been removed from the rubber hand. An interpretative phenomenological analysis revealed that the structure of this experience shares a wide range of sensory attributes with subjective reports of phantom limb experience. For example, when the space where the ring finger should have been on the rubber hand was stroked, 93% of participants (i.e., 28/30) reported the vivid presence of a finger that they could not see and a total of 57% (16/28) of participants who felt that the finger was present reported one or more additional sensory qualities such as tingling or numbness (25%; 7/28) and alteration in the perceived size of the finger (50%; 14/28). These experiences indicate the adaptability of body experience and share some characteristics of the way that phantom limbs are described. Participants attributed changes to the shape and size of their “missing” finger to the way in which the experimenter mimed stroking in the area occupied by the missing finger. This alteration of body perception is similar to the phenomenon of telescoping experienced by people with phantom limbs and suggests that our sense of embodiment not only depends on internal body representations but on perceptual information coming from peripersonal space. PMID:23355829

The effects of prosthetic foot stiffness on transtibial amputee walking mechanics and balance control during turning.

PubMed

Shell, Courtney E; Segal, Ava D; Klute, Glenn K; Neptune, Richard R

2017-11-01

Little evidence exists regarding how prosthesis design characteristics affect performance in tasks that challenge mediolateral balance such as turning. This study assesses the influence of prosthetic foot stiffness on amputee walking mechanics and balance control during a continuous turning task. Three-dimensional kinematic and kinetic data were collected from eight unilateral transtibial amputees as they walked overground at self-selected speed clockwise and counterclockwise around a 1-meter circle and along a straight line. Subjects performed the walking tasks wearing three different ankle-foot prostheses that spanned a range of sagittal- and coronal-plane stiffness levels. A decrease in stiffness increased residual ankle dorsiflexion (10-13°), caused smaller adaptations (<5°) in proximal joint angles, decreased residual and increased intact limb body support, increased residual limb propulsion and increased intact limb braking for all tasks. While changes in sagittal-plane joint work due to decreased stiffness were generally consistent across tasks, effects on coronal-plane hip work were task-dependent. When the residual limb was on the inside of the turn and during straight-line walking, coronal-plane hip work increased and coronal-plane peak-to-peak range of whole-body angular momentum decreased with decreased stiffness. Changes in sagittal-plane kinematics and kinetics were similar to those previously observed in straight-line walking. Mediolateral balance improved with decreased stiffness, but adaptations in coronal-plane angles, work and ground reaction force impulses were less systematic than those in sagittal-plane measures. Effects of stiffness varied with the residual limb inside versus outside the turn, which suggests that actively adjusting stiffness to turn direction may be beneficial. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mealtime Manual for the Aged and Handicapped.

ERIC Educational Resources Information Center

Klinger, Judith Lannefeld; And Others

Specific techniques to alleviate difficulties encountered in routine kitchen tasks are described for the elderly and the handicapped, particularly those persons with upper extremity weakness or amputees, arthritis, incoordination, wheelchair confinement, loss of sensation, and limited vision. Helpful information is provided in areas of kitchen…

Preliminary Evaluation of a Diagnostic Tool for Prosthetics

DTIC Science & Technology

2017-10-01

volume change. Processing algorithms for data from the activity monitors were modified to run more efficiently so that large datasets could be...left) and blade style prostheses (right). Figure 4: Ankle ActiGraph correct position demonstrated for a left leg below-knee amputee cylindrical

Neural interfaces for control of upper limb prostheses: the state of the art and future possibilities.

PubMed

Schultz, Aimee E; Kuiken, Todd A

2011-01-01

Current treatment of upper limb amputation restores some degree of functional ability, but this ability falls far below the standard set by the natural arm. Although acceptance rates can be high when patients are highly motivated and receive proper training and care, current prostheses often fail to meet the daily needs of amputees and frequently are abandoned. Recent advancements in science and technology have led to promising methods of accessing neural information for communication or control. Researchers have explored invasive and noninvasive methods of connecting with muscles, nerves, or the brain to provide increased functionality for patients experiencing disease or injury, including amputation. These techniques offer hope of more natural and intuitive prosthesis control, and therefore increased quality of life for amputees. In this review, we discuss the current state of the art of neural interfaces, particularly those that may find application within the prosthetics field. Copyright © 2011 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Prosthetic ankle push-off work reduces metabolic rate but not collision work in non-amputee walking.

PubMed

Caputo, Joshua M; Collins, Steven H

2014-12-03

Individuals with unilateral below-knee amputation expend more energy than non-amputees during walking and exhibit reduced push-off work and increased hip work in the affected limb. Simple dynamic models of walking suggest a possible solution, predicting that increasing prosthetic ankle push-off should decrease leading limb collision, thereby reducing overall energy requirements. We conducted a rigorous experimental test of this idea wherein ankle-foot prosthesis push-off work was incrementally varied in isolation from one-half to two-times normal levels while subjects with simulated amputation walked on a treadmill at 1.25 m · s(-1). Increased prosthesis push-off significantly reduced metabolic energy expenditure, with a 14% reduction at maximum prosthesis work. In contrast to model predictions, however, collision losses were unchanged, while hip work during swing initiation was decreased. This suggests that powered ankle push-off reduces walking effort primarily through other mechanisms, such as assisting leg swing, which would be better understood using more complete neuromuscular models.

Prosthetic ankle push-off work reduces metabolic rate but not collision work in non-amputee walking

NASA Astrophysics Data System (ADS)

Caputo, Joshua M.; Collins, Steven H.

2014-12-01

Individuals with unilateral below-knee amputation expend more energy than non-amputees during walking and exhibit reduced push-off work and increased hip work in the affected limb. Simple dynamic models of walking suggest a possible solution, predicting that increasing prosthetic ankle push-off should decrease leading limb collision, thereby reducing overall energy requirements. We conducted a rigorous experimental test of this idea wherein ankle-foot prosthesis push-off work was incrementally varied in isolation from one-half to two-times normal levels while subjects with simulated amputation walked on a treadmill at 1.25 m.s-1. Increased prosthesis push-off significantly reduced metabolic energy expenditure, with a 14% reduction at maximum prosthesis work. In contrast to model predictions, however, collision losses were unchanged, while hip work during swing initiation was decreased. This suggests that powered ankle push-off reduces walking effort primarily through other mechanisms, such as assisting leg swing, which would be better understood using more complete neuromuscular models.

Prosthetic ankle push-off work reduces metabolic rate but not collision work in non-amputee walking

PubMed Central

Caputo, Joshua M.; Collins, Steven H.

2014-01-01

Individuals with unilateral below-knee amputation expend more energy than non-amputees during walking and exhibit reduced push-off work and increased hip work in the affected limb. Simple dynamic models of walking suggest a possible solution, predicting that increasing prosthetic ankle push-off should decrease leading limb collision, thereby reducing overall energy requirements. We conducted a rigorous experimental test of this idea wherein ankle-foot prosthesis push-off work was incrementally varied in isolation from one-half to two-times normal levels while subjects with simulated amputation walked on a treadmill at 1.25 m·s−1. Increased prosthesis push-off significantly reduced metabolic energy expenditure, with a 14% reduction at maximum prosthesis work. In contrast to model predictions, however, collision losses were unchanged, while hip work during swing initiation was decreased. This suggests that powered ankle push-off reduces walking effort primarily through other mechanisms, such as assisting leg swing, which would be better understood using more complete neuromuscular models. PMID:25467389

Studies on regeneration of central nervous system and social ability of the earthworm Eudrilus eugeniae.

PubMed

Gopi Daisy, Nino; Subramanian, Elaiya Raja; Selvan Christyraj, Jackson Durairaj; Sudalai Mani, Dinesh Kumar; Selvan Christyraj, Johnson Retnaraj Samuel; Ramamoorthy, Kalidas; Arumugaswami, Vaithilingaraja; Sivasubramaniam, Sudhakar

2016-09-01

Earthworms are segmented invertebrates that belong to the phylum Annelida. The segments can be divided into the anterior, clitellar and posterior parts. If the anterior part of the earthworm, which includes the brain, is amputated, the worm would essentially survive even in the absence of the brain. In these brain amputee-derived worms, the nerve cord serves as the primary control center for neurological function. In this current work, we studied changes in the expression levels of anti-acetylated tubulin and serotonin as the indicators of neuro-regenerative processes. The data reveal that the blastemal tissues express the acetylated tubulin and serotonin from day four and that the worm amputated at the 7th segment takes 30 days to complete the regeneration of brain. The ability of self-assemblage is one of the specific functions of the earthworm's brain. The brain amputee restored the ability of self-assemblage on the eighth day.

Use of prostheses and footwear in 110 inner-city partial-foot amputees.

PubMed

Sobel, E; Japour, C J; Giorgini, R J; Levitz, S J; Richardson, H L

2001-01-01

The number of partial-foot amputations performed is increasing, and many recommendations have been made regarding the use of prostheses and footwear designed to prevent higher-level amputations in this population. The present study investigated the use of prostheses and shoe inserts and the types of footwear worn by partial-foot amputees in the inner city to determine whether previous recommendations are being followed as well as whether new prosthetic styles are being used. The study surveyed 110 patients (73 men and 37 women) with a mean age of 58.6 years (range, 21 to 86 years) with partial-foot amputations of all levels. The results showed that about one-half of all patients wore a shoe-insert orthosis. Although 54% wore some form of special footwear to accommodate and protect the residual foot, no patient in this study wore a shoe with a rocker-bottom sole. Only one patient with a transmetatarsal amputation used a brace and only one patient in the entire study wore a modern cosmetic foot prosthesis.

Illusory movement perception improves motor control for prosthetic hands.

PubMed

Marasco, Paul D; Hebert, Jacqueline S; Sensinger, Jon W; Shell, Courtney E; Schofield, Jonathon S; Thumser, Zachary C; Nataraj, Raviraj; Beckler, Dylan T; Dawson, Michael R; Blustein, Dan H; Gill, Satinder; Mensh, Brett D; Granja-Vazquez, Rafael; Newcomb, Madeline D; Carey, Jason P; Orzell, Beth M

2018-03-14

To effortlessly complete an intentional movement, the brain needs feedback from the body regarding the movement's progress. This largely nonconscious kinesthetic sense helps the brain to learn relationships between motor commands and outcomes to correct movement errors. Prosthetic systems for restoring function have predominantly focused on controlling motorized joint movement. Without the kinesthetic sense, however, these devices do not become intuitively controllable. We report a method for endowing human amputees with a kinesthetic perception of dexterous robotic hands. Vibrating the muscles used for prosthetic control via a neural-machine interface produced the illusory perception of complex grip movements. Within minutes, three amputees integrated this kinesthetic feedback and improved movement control. Combining intent, kinesthesia, and vision instilled participants with a sense of agency over the robotic movements. This feedback approach for closed-loop control opens a pathway to seamless integration of minds and machines. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Development of the transtibial prosthesis controlled pneumatically and electrically by microcomputer system.

PubMed

Shimada, Youichi; Terayama, Yukio

2006-01-01

This report represents the development of the prototype transtibial prosthesis to assist a smooth and comfortable walking for an unilateral amputee. This prosthesis is composed of two air cylinders, solenoid valves, portable and small air tank for compressed air storage, a multiple sensor system and a microprocessor. Two air cylinders are located around the rods to act as antagonistic and agonistic muscles. The system causes flexion and extension of the foot plate jointed at the ankle with compressed air, injected -or discharged via a solenoid or electromagnetic valves. The valves or solenoids are controlled with a microprocessor (Microchip Technology Inc., PIC16F876), the microprocessor generates control signals to the interface circuits for valve opening and closing consistent with the foot position during the walking phase. The control patterns generated in the microprocessor are modified with feedback from the touch sensor, ankle joint angle sensor and the two dimensional acceleration sensor. The primary walking pattern for an individual amputee should be developed through the gait analysis with video.

Design and energetic evaluation of a prosthetic knee joint actuator with a lockable parallel spring.

PubMed

Geeroms, J; Flynn, L; Jimenez-Fabian, R; Vanderborght, B; Lefeber, D

2017-02-03

There are disadvantages to existing damping knee prostheses which cause an asymmetric gait and higher metabolic cost during level walking compared to non-amputees. Most existing active knee prostheses which could benefit the amputees use a significant amount of energy and require a considerable motor. In this work, a novel semi-active actuator with a lockable parallel spring for a prosthetic knee joint has been developed and tested. This actuator is able to provide an approximation of the behavior of a healthy knee during most of the gait cycle of level walking. This actuator is expanded with a series-elastic actuator to mimic the full gait cycle and enable its use in other functional tasks like stair climbing and sit-to-stance. The proposed novel actuator reduces the energy consumption for the same trajectory with respect to a compliant or directly-driven prosthetic active knee joint and improves the approximation of healthy knee behavior during level walking compared to passive or variable damping knee prostheses.

Simulation of a slope adapting ankle prosthesis provided by semi-active damping.

PubMed

LaPrè, Andrew K; Sup, Frank

2011-01-01

Modern passive prosthetic foot/ankles cannot adapt to variations in ground slope. The lack of active adaptation significantly compromises an amputee's balance and stability on uneven terrains. To address this deficit, this paper proposes an ankle prosthesis that uses semi-active damping as a mechanism to provide active slope adaptation. The conceptual ankle prosthesis consists of a modulated damper in series with a spring foot that allows the foot to conform to the angle of the surface in the sagittal plane. In support of this approach, biomechanics data is presented showing unilateral transtibial amputees stepping on a wedge with their daily-use passive prosthesis. Based on this data, a simulation of the ankle prosthesis with semi-active damping is developed. The model shows the kinematic adaptation of the prosthesis to sudden changes in ground slope. The results show the potential of an ankle prosthesis with semi-active damping to actively adapt to the ground slope at each step.

Gait and balance of transfemoral amputees using passive mechanical and microprocessor-controlled prosthetic knees.

PubMed

Kaufman, K R; Levine, J A; Brey, R H; Iverson, B K; McCrady, S K; Padgett, D J; Joyner, M J

2007-10-01

Microprocessor-controlled knee joints appeared on the market a decade ago. These joints are more sophisticated and more expensive than mechanical ones. The literature is contradictory regarding changes in gait and balance when using these sophisticated devices. This study employed a crossover design to assess the comparative performance of a passive mechanical knee prosthesis compared to a microprocessor-controlled knee joint in 15 subjects with an above-knee amputation. Objective measurements of gait and balance were obtained. Subjects demonstrated significantly improved gait characteristics after receiving the microprocessor-controlled prosthetic knee joint (p<0.01). Improvements in gait were a transition from a hyperextended knee to a flexed knee during loading response which resulted in a change from an internal knee flexor moment to a knee extensor moment. The participants' balance also improved (p<0.01). All conditions of the Sensory Organization Test (SOT) demonstrated improvements in equilibrium score. The composite score also increased. Transfemoral amputees using a microprocessor-controlled knee have significant improvements in gait and balance.

Sensory feedback add-on for upper-limb prostheses.

PubMed

Fallahian, Nader; Saeedi, Hassan; Mokhtarinia, Hamidreza; Tabatabai Ghomshe, Farhad

2017-06-01

Sensory feedback systems have been of great interest in upper-limb prosthetics. Despite tremendous research, there are no commercial modality-matched feedback systems. This article aims to introduce the first detachable and feedback add-on option that can be attached to in-use prostheses. A sensory feedback system was tested on a below-elbow myoelectric prosthesis. The aim was to have the amputee grasp fragile objects without crushing while other accidental feedback sources were blocked. A total of 8 successful trials (out of 10) showed that sensory feedback system decreased the amputee's visual dependency by improving awareness of his prosthesis. Sensory feedback system can be used either as post-fabrication (prosthetic add-on option) or para-fabrication (incorporated into prosthetic design). The use of these direct feedback systems can be explored with a current prosthesis before ordering new high-tech prosthesis. Clinical relevance This technical note introduces the first attach/detach-able sensory feedback system that can simply be added to in-use (myo)electric prosthesis, with no obligation to change prosthesis design or components.

[2-year results of leg amputation in Hungary based on a nationwide data base].

PubMed

Kullmann, L; Belicza, E; László, G

1997-09-14

Authors review nation-wide hospital data of amputees over two years in order to make comparison with similar data gathered about 20 years ago. Data were provided by the National Medical Records Centre and processed by own developed programmes. The quality level of data validity is slightly criticised. The cause of amputation was most often vascular disease, amputees were elderly and large majority of amputation surgery was carried out on the lower limb. The rate of below-knee amputation has gone up favourably over the 20 years, but there are large regional differences within the country. Mortality parameters remarkably exceed those of foreign countries. Regarding compromised data accuracy, still there are ways of exploiting data in favour of quality improvement of care, e.g. improve below-knee amputation rate, reduce mortality. Publication of data can be of bench-marking importance for hospitals by enabling them to compare own results with those of other hospitals, as well as develop and improve performance.

Long-term follow-up of unilateral transfemoral amputees from the Vietnam war.

PubMed

Dougherty, Paul J

2003-04-01

Despite their frequency, few reports exist concerning the initial and long-term consequences of battle-incurred unilateral transfemoral amputations. A retrospective cohort design was used to measure the long-term health of transfemoral battle amputees treated at a single hospital during the Vietnam War. Data collection consisted of medical record abstraction and a follow-up questionnaire that included the SF-36 Health Survey. Forty-six patients responded to the survey an average of 28 years after injury. Compared with the controls, patient responses to the SF-36 were significantly (p < 0.01) less in all categories except Mental Health and Vitality. Forty-three (93.5%) are or have been married. Forty-one (89.1%) are or have been employed an average of 20.1 years. Forty patients (87%) wore a prosthesis an average of 13.5 h/day. Although the patients do relatively well with employment and marriage stability, the low SF-36 scores suggest a significant disability.

Skin problems of the stump in lower-limb amputees: 2. Influence on functioning in daily life.

PubMed

Meulenbelt, Henk E J; Geertzen, Jan H B; Jonkman, Marcel F; Dijkstra, Pieter U

2011-03-01

The aim of this study was to analyse the influence of stump skin problems on functioning in daily life in lower-limb amputees. A cross-sectional study was performed by means of a questionnaire containing 9 questions assessing functioning in daily life. Question scores were added to give a total score (range 0 (no influence) to 27 (maximum negative influence)). Two thousand and thirty-nine people were invited to participate, with 805 participants completing a questionnaire. Of these, 507 reported one or more skin problems. Skin problems had a negative influence on ability to perform household tasks, prosthesis use, social functioning, and participation in sports. The mean total score was 5.5 ± 4.1. This correlated significantly with the number of skin complaints (r = 0.483; p = 0.01). In linear regression analyses, gender (β = -0.15) and number of skin problems (β = 0.25) accounted for 23% of the total score. This study confirms the influence of skin problems on functioning in daily life.

Determinants of Attitudes toward People with Disabilities.

ERIC Educational Resources Information Center

Esses, Victoria M.; And Others

This study examined the applicability of a multicomponent model to understanding the bases of attitudes toward people with disabilities. The 108 students (65 females, 43 males) reported their attitudes toward three groups -- amputees, people with AIDS (Acquired Immune Deficiency Syndrome), and the chronically depressed. They also completed…

THE LIMB-DEFICIENT CHILD.

ERIC Educational Resources Information Center

BLAKESLEE, BERTON

DESIGNED AS A SOURCE OF REFERENCE FOR TEACHING, THIS BOOK PRESENTS TECHNIQUES AND PROCEDURES USED IN THE CHILD AMPUTEE PROSTHETICS PROJECT (SCHOOL OF MEDICINE, UNIVERSITY OF CALIFORNIA AT LOS ANGELES). THE FIRST CHAPTER DISCUSSES THE ROLE OF THE MEDICAL DIRECTOR OVERSEEING INITIAL INTERVIEWS WITH CHILDREN AND THEIR PARENTS, MEDICAL EXAMINATIONS,…

Prosthetic Hand For Holding Rods, Tools, And Handles

NASA Technical Reports Server (NTRS)

Belcher, Jewell G., Jr.; Vest, Thomas W.

1995-01-01

Prosthetic hand with quick-grip/quick-release lever broadens range of specialized functions available to lower-arm amputee by providing improved capabilities for gripping rods, tools, handles, and like. Includes two stationary lower fingers opposed by one pivoting upper finger. Lever operates in conjunction with attached bracket.

Application of a postulate based control theory for an artificial arm

NASA Technical Reports Server (NTRS)

Jacobsen, S. C.; Jerard, R. B.

1975-01-01

The biocontroller, remnant of the natural arm, and feedback elements must be considered in designing a controller for an above elbow artificial arm for amputees. This fundamental postulate is used to derive equations for developing the controller, which is shown in block diagrams.

A motion-classification strategy based on sEMG-EEG signal combination for upper-limb amputees.

PubMed

Li, Xiangxin; Samuel, Oluwarotimi Williams; Zhang, Xu; Wang, Hui; Fang, Peng; Li, Guanglin

2017-01-07

Most of the modern motorized prostheses are controlled with the surface electromyography (sEMG) recorded on the residual muscles of amputated limbs. However, the residual muscles are usually limited, especially after above-elbow amputations, which would not provide enough sEMG for the control of prostheses with multiple degrees of freedom. Signal fusion is a possible approach to solve the problem of insufficient control commands, where some non-EMG signals are combined with sEMG signals to provide sufficient information for motion intension decoding. In this study, a motion-classification method that combines sEMG and electroencephalography (EEG) signals were proposed and investigated, in order to improve the control performance of upper-limb prostheses. Four transhumeral amputees without any form of neurological disease were recruited in the experiments. Five motion classes including hand-open, hand-close, wrist-pronation, wrist-supination, and no-movement were specified. During the motion performances, sEMG and EEG signals were simultaneously acquired from the skin surface and scalp of the amputees, respectively. The two types of signals were independently preprocessed and then combined as a parallel control input. Four time-domain features were extracted and fed into a classifier trained by the Linear Discriminant Analysis (LDA) algorithm for motion recognition. In addition, channel selections were performed by using the Sequential Forward Selection (SFS) algorithm to optimize the performance of the proposed method. The classification performance achieved by the fusion of sEMG and EEG signals was significantly better than that obtained by single signal source of either sEMG or EEG. An increment of more than 14% in classification accuracy was achieved when using a combination of 32-channel sEMG and 64-channel EEG. Furthermore, based on the SFS algorithm, two optimized electrode arrangements (10-channel sEMG + 10-channel EEG, 10-channel sEMG + 20-channel EEG) were obtained with classification accuracies of 84.2 and 87.0%, respectively, which were about 7.2 and 10% higher than the accuracy by using only 32-channel sEMG input. This study demonstrated the feasibility of fusing sEMG and EEG signals towards improving motion classification accuracy for above-elbow amputees, which might enhance the control performances of multifunctional myoelectric prostheses in clinical application. The study was approved by the ethics committee of Institutional Review Board of Shenzhen Institutes of Advanced Technology, and the reference number is SIAT-IRB-150515-H0077.

Effects of Handicap and Job Characteristics on Selection Evaluations.

ERIC Educational Resources Information Center

Rose, Gerald L.; Brief, Arthur P.

1979-01-01

Business administration students evaluated a hypothetical job applicant who was either an amputee, an epileptic, or "normal." The hypothetical job openings varied as to levels of supervisory responsibility and public contact. With some noted exceptions, the handicapped applicants were evaluated no differently than the normal applicants.…

Research and Practice with Congenital Amputees: Making the Whole Greater than the Sum of Its Parts.

ERIC Educational Resources Information Center

Minnes, Patricia M.; Stack, Dale M.

1990-01-01

This paper highlights the need for research on the motor, cognitive, and psychological development of children with congenital limb deficiencies. Issues reviewed include optimal age for prosthesis fitting, training procedures, prosthesis usage, cognitive deficits, and vulnerability to psychosocial problems. (Author/DB)

Dissemination of an Innovative Technical Therapy through an Evaluated Practical Workshop Using Live Patient Simulators.

ERIC Educational Resources Information Center

Dykes, Michael H. M.; And Others

1981-01-01

The use of a practical workshop to disseminate an innovative technical therapy which must be learned and practiced under supervision is described. A removable rigid dressing for below-the-knee amputees, developed at the Veterans Administration Lakeside Medical Center, is discussed. (MLW)

The Store Challenge

ERIC Educational Resources Information Center

Roman, Harry T.

2014-01-01

Biomedical and robotic technologies are merging to present a wonderful opportunity to develop artificial limbs and prosthetic devices for humans injured on the job, in the military, or due to disease. In this challenge, students will have the opportunity to design a store or online service that specifically dedicates itself to amputees. Described…

Physiologically Relevant Prosthetic Limb Movement Feedback for Upper and Lower Extremity Amputees

DTIC Science & Technology

2016-10-01

upper arm (elbow movement), Upper leg (knee movement) and lower leg ( ankle movement) to provide a physiologically relevant sense of limb movement...Additionally a BOA cable tensioning system is passed through these plates and anchored to the external surface of the socket. When tension is applied the

Studying Upper-Limb Amputee Prosthesis Use to Inform Device Design

DTIC Science & Technology

2015-10-01

the study. This equipment has included a modified GoPro head-mounted camera and a Vicon 13-camera optical motion capture system, which was not part...also completed for relevant members of the study team. 4. The head-mounted camera setup has been established (a modified GoPro Hero 3 with external

Training Internal Medicine Residents in Geriatrics.

ERIC Educational Resources Information Center

Wolf-Klein, Gisele P.; And Others

1983-01-01

A four-week geriatric rotation in a nursing home that emphasized rehabilitation for stroke victims, patients with fractured hips, and amputees, and the team approach in care for the elderly is described. Student response was very positive, student sensitivity was improved, and all students felt the team approach could be applied to later practice.…

Repeatability and Validity of the Combined Arm-Leg (Cruiser) Ergometer

ERIC Educational Resources Information Center

Simmelink, Elisabeth K.; Wempe, Johan B.; Geertzen, Jan H. B.; Dekker, Rienk

2009-01-01

The measurement of physical fitness of lower limb amputees is difficult, as the commonly used ergometer tests have limitations. A combined arm-leg (Cruiser) ergometer might be valuable. The aim of this study was to establish the repeatability and validity of the combined arm-leg (Cruiser) ergometer. Thirty healthy volunteers carried out three…

Development of nylon-based artificial muscles for the usage in robotic prosthetic limb

NASA Astrophysics Data System (ADS)

Atikah, Nurul Anis; Weng, Leong Yeng; Anuar, Adzly; Fat, Chau Chien; Abidin, Izham Zainal; Sahari, Khairul Salleh Mohamed

2017-09-01

This paper describes the development of nylon-based artificial muscles that is intended to be used in prosthetic limb for young amputees. Prosthetic limbs are very expensive and this situation is further compounded for young amputees who are very quickly out-grow their prosthesis. The proposed artificial muscles are made of nylon fishing strings from various size such as 0.45mm, 0.55mm, 0.65mm and 1.00mm. These fishing strings were twisted into coils to create Super Coiled Polymers (SCP) and tested using hot air blower. These artificial muscles react counterintuitively, where when it is exposed to heat, contracts, and when cooled, expands. Peltier devices, when switched-on acts as heat pump, where one side is hot and the other is cold. This phenomenon, when affixed in between 2 SCP's, creates tandem motion similar to triceps and biceps. As initial study, the hot side of the Peltier module was tested using these artificial muscles. The string was measured for both its force production, length contraction, the initial results were promising.

Myoelectric control of prosthetic hands: state-of-the-art review

PubMed Central

Geethanjali, Purushothaman

2016-01-01

Myoelectric signals (MES) have been used in various applications, in particular, for identification of user intention to potentially control assistive devices for amputees, orthotic devices, and exoskeleton in order to augment capability of the user. MES are also used to estimate force and, hence, torque to actuate the assistive device. The application of MES is not limited to assistive devices, and they also find potential applications in teleoperation of robots, haptic devices, virtual reality, and so on. The myoelectric control-based prosthetic hand aids to restore activities of daily living of amputees in order to improve the self-esteem of the user. All myoelectric control-based prosthetic hands may not have similar operations and exhibit variation in sensing input, deciphering the signals, and actuating prosthetic hand. Researchers are focusing on improving the functionality of prosthetic hand in order to suit the user requirement with the different operating features. The myoelectric control differs in operation to accommodate various external factors. This article reviews the state of the art of myoelectric prosthetic hand, giving description of each control strategy. PMID:27555799

Prosthetic Leg Control in the Nullspace of Human Interaction.

PubMed

Gregg, Robert D; Martin, Anne E

2016-07-01

Recent work has extended the control method of virtual constraints, originally developed for autonomous walking robots, to powered prosthetic legs for lower-limb amputees. Virtual constraints define desired joint patterns as functions of a mechanical phasing variable, which are typically enforced by torque control laws that linearize the output dynamics associated with the virtual constraints. However, the output dynamics of a powered prosthetic leg generally depend on the human interaction forces, which must be measured and canceled by the feedback linearizing control law. This feedback requires expensive multi-axis load cells, and actively canceling the interaction forces may minimize the human's influence over the prosthesis. To address these limitations, this paper proposes a method for projecting virtual constraints into the nullspace of the human interaction terms in the output dynamics. The projected virtual constraints naturally render the output dynamics invariant with respect to the human interaction forces, which instead enter into the internal dynamics of the partially linearized prosthetic system. This method is illustrated with simulations of a transfemoral amputee model walking with a powered knee-ankle prosthesis that is controlled via virtual constraints with and without the proposed projection.

When less is more - Implicit preference for incomplete bodies in xenomelia.

PubMed

Macauda, Gianluca; Bekrater-Bodmann, Robin; Brugger, Peter; Lenggenhager, Bigna

2017-01-01

Individuals with xenomelia identify with an amputated rather than with their physically complete, healthy body. They often mimic amputees and show a strong admiration of and sexual attraction towards them. Here we investigated for the first time empirically whether such unusual preference for amputated bodies is present also on an implicit level. Using the well-validated Implicit Association Test we show that individuals with xenomelia manifested a stronger implicit and explicit preference for amputated bodies than a normally-limbed control group and a group of involuntary amputees did. Interestingly, the two latter groups did not differ in their implicit and explicit preference for complete versus amputated bodies. These findings are an important step in understanding how deeply rooted attitudes about a socially normative body appearance may be influenced by a developmentally disordered experience of one's own bodily self. We conclude that this is the first behavioral evidence demonstrating a conflict of self-identification on an implicit level and this enriches current understandings of xenomelia as a primarily neurological disorder. Copyright © 2016 Elsevier Ltd. All rights reserved.

A powered prosthetic ankle joint for walking and running.

PubMed

Grimmer, Martin; Holgate, Matthew; Holgate, Robert; Boehler, Alexander; Ward, Jeffrey; Hollander, Kevin; Sugar, Thomas; Seyfarth, André

2016-12-19

Current prosthetic ankle joints are designed either for walking or for running. In order to mimic the capabilities of an able-bodied, a powered prosthetic ankle for walking and running was designed. A powered system has the potential to reduce the limitations in range of motion and positive work output of passive walking and running feet. To perform the experiments a controller capable of transitions between standing, walking, and running with speed adaptations was developed. In the first case study the system was mounted on an ankle bypass in parallel with the foot of a non-amputee subject. By this method the functionality of hardware and controller was proven. The Walk-Run ankle was capable of mimicking desired torque and angle trajectories in walking and running up to 2.6 m/s. At 4 m/s running, ankle angle could be matched while ankle torque could not. Limited ankle output power resulting from a suboptimal spring stiffness value was identified as a main reason. Further studies have to show to what extent the findings can be transferred to amputees.

Upper limb amputees can be induced to experience a rubber hand as their own

PubMed Central

Rosén, Birgitta; Stockselius, Anita; Ragnö, Christina; Köhler, Peter; Lundborg, Göran

2008-01-01

We describe how upper limb amputees can be made to experience a rubber hand as part of their own body. This was accomplished by applying synchronous touches to the stump, which was out of view, and to the index finger of a rubber hand, placed in full view (26 cm medial to the stump). This elicited an illusion of sensing touch on the artificial hand, rather than on the stump and a feeling of ownership of the rubber hand developed. This effect was supported by quantitative subjective reports in the form of questionnaires, behavioural data in the form of misreaching in a pointing task when asked to localize the position of the touch, and physiological evidence obtained by skin conductance responses when threatening the hand prosthesis. Our findings outline a simple method for transferring tactile sensations from the stump to a prosthetic limb by tricking the brain, thereby making an important contribution to the field of neuroprosthetics where a major goal is to develop artificial limbs that feel like a real parts of the body. PMID:19074189

Amputee socks: thickness of multiple socks.

PubMed

Cagle, John C; Yu, Alan J; Ciol, Marcia A; Sanders, Joan E

2014-10-01

It is unclear how total sock ply and thickness are related when more than one sock is worn. The objectives were to determine whether the thickness of one multi-ply amputee sock of ply P was the same as the thickness of a stack of reduced-ply socks of total ply P, and whether the thickness of N single socks stacked one on top of the other was equal to the sum (1 to N) of the single sock thicknesses. Using a custom instrument, compressive stresses were applied while sock thickness was measured. The thickness of one multi-ply sock of ply P was typically less than the thickness of a stack of reduced-ply socks of total ply P. The thickness of N single socks stacked one on top of the other was approximately equal to the sum (1 to N) of the single sock thicknesses. Our findings suggest three 1-ply socks to be 20% greater in thickness than one 3-ply sock, and one 3-ply + two 1-ply socks to be 30% greater in thickness than one 5-ply sock. © The International Society for Prosthetics and Orthotics 2013.

Amputee Socks: Thickness of Multiple Socks

PubMed Central

Cagle, John C; Yu, Alan J; Ciol, Marcia A; Sanders, JE

2015-01-01

Background and Aim It is unclear how total sock ply and thickness are related when more than one sock is worn. The objectives were to determine if the thickness of one multi-ply amputee sock of ply P was the same as the thickness of a stack of reduced-ply socks of total ply P; and if the thickness of N single socks stacked one on top of the other was equal to the sum (1 to N) of the single sock thicknesses. Technique Using a custom instrument, compressive stresses were applied while sock thickness was measured. Discussion The thickness of one multi-ply sock of ply P was typically less than the thickness of a stack of reduced-ply socks of total ply P. The thickness of N single socks stacked one on top of the other was approximately equal to the sum (1 to N) of the single sock thicknesses. Clinical Relevance Our findings suggest three 1-ply socks to be 20% greater in thickness than one 3-ply sock, and one 3-ply + two 1-ply socks to be 30% greater in thickness than one 5-ply sock. PMID:24240023

Demographics of Lower Limb Amputations in the Pakistan Military: A Single Center, Three-Year Prospective Survey.

PubMed

Rathore, Farooq A; Ayaz, Saeed B; Mansoor, Sahibzada N; Qureshi, Ali R; Fahim, Muhammad

2016-04-11

INTRODUCTION : The Pakistan military has been actively engaged in the war against terror for more than a decade. Many officers and soldiers have lost their limbs in this war. But the data on traumatic lower limb amputations in Pakistan is sparse. The aim of this study is to prospectively document the epidemiological profile of lower limb military amputees presenting at the largest rehabilitation centre of Pakistan over a three-year period. MATERIALS & METHODS : A prospective three-year survey was conducted at the Armed Forces Institute of Rehabilitation Medicine (AFIRM), Pakistan. One hundred twenty-three consecutive patients with lower limb amputations were enrolled in the survey. The demographic data, etiology, associated injuries, complications profile, and type of prosthesis provided were documented. The data analysis was done using the statistical analysis tool SPSS V 20 (IBM®,NY, USA). RESULTS : All patients were male. Most had traumatic amputation (119), were between 20-40 years (106), with unilateral amputation (115). Mine blast injury was the leading cause in 73 (59.3%) and most (58.5%) were fitted with modular prosthesis. Transtibial amputation was the commonest level (65), followed by transfemoral (30). The time of surgical amputation was not documented in 87% of the patients. Half of the patients (54%) had associated injuries. Seventy-nine patients had at least one complication with phantom pain being the commonest in 25% cases. CONCLUSIONS : This is the largest prospective demographic survey of lower limb amputees in Pakistan military to date. Scores of soldiers and civilians in Pakistan have suffered lower limb amputation. The availability of demographic data can improve the trauma and rehabilitation services for better understanding and management of such cases. There is a need to conduct large scale community-based epidemiological surveys to direct future policies and develop amputee rehabilitation services in the public sector.

Demographics of Lower Limb Amputations in the Pakistan Military: A Single Center, Three-Year Prospective Survey

PubMed Central

Ayaz, Saeed B; Mansoor, Sahibzada N; Qureshi, Ali R; Fahim, Muhammad

2016-01-01

Introduction  The Pakistan military has been actively engaged in the war against terror for more than a decade. Many officers and soldiers have lost their limbs in this war. But the data on traumatic lower limb amputations in Pakistan is sparse. The aim of this study is to prospectively document the epidemiological profile of lower limb military amputees presenting at the largest rehabilitation centre of Pakistan over a three-year period. Materials & methods  A prospective three-year survey was conducted at the Armed Forces Institute of Rehabilitation Medicine (AFIRM), Pakistan. One hundred twenty-three consecutive patients with lower limb amputations were enrolled in the survey. The demographic data, etiology, associated injuries, complications profile, and type of prosthesis provided were documented. The data analysis was done using the statistical analysis tool SPSS V 20 (IBM®,NY, USA).  Results  All patients were male. Most had traumatic amputation (119), were between 20–40 years (106), with unilateral amputation (115). Mine blast injury was the leading cause in 73 (59.3%) and most (58.5%) were fitted with modular prosthesis. Transtibial amputation was the commonest level (65), followed by transfemoral (30). The time of surgical amputation was not documented in 87% of the patients. Half of the patients (54%) had associated injuries. Seventy-nine patients had at least one complication with phantom pain being the commonest in 25% cases. Conclusions  This is the largest prospective demographic survey of lower limb amputees in Pakistan military to date. Scores of soldiers and civilians in Pakistan have suffered lower limb amputation. The availability of demographic data can improve the trauma and rehabilitation services for better understanding and management of such cases. There is a need to conduct large scale community-based epidemiological surveys to direct future policies and develop amputee rehabilitation services in the public sector. PMID:27186448

The influence of lower limb amputation level on the approach in the amputee long jump.

PubMed

Nolan, Lee; Lees, Adrian

2007-02-15

In this study, we investigated the adjustments to posture, kinematic and temporal characteristics of performance made by lower limb amputees during the last few strides in preparation for long jump take-off. Six male unilateral trans-femoral and seven male unilateral trans-tibial amputees competing in a World Championships final were filmed in the sagittal plane using a 100-Hz digital video camera positioned so that the last three strides to take-off were visible. After digitizing using a nine-segment model, a range of kinematic variables were computed to define technique characteristics. Both the trans-femoral and trans-tibial athletes appeared to achieve their reduction in centre of mass during the flight phase between strides, and did so mainly by extending the flight time by increasing stride length, achieved by a greater flexion of the hip joint of the touch-down leg. The trans-tibial athletes appeared to adopt a technique similar to that previously reported for able-bodied athletes. They lowered their centre of mass most on their second last stride (-1.6% of body height compared with -1.4% on the last stride) and used a flexed knee at take-off on the last stride, but they were less able to control their downward velocity at touch-down (-0.4 m x s(-1)). Both this and their restricted approach speed (8.9 m x s(-1) at touch-down), rather than technique limitations, influenced their jump performance. The trans-femoral athletes lowered their centre of mass most on the last stride (-2.3% of body height compared with -1.6% on the second last stride) and, as they were unable to flex their prosthetic knee sufficiently, achieved this by abducting their prosthetic leg during the support phase, which led to a large downward velocity at touch-down (-0.6 m x s(-1)). This, combined with their slower approach velocity (7.1 m x s(-1) at touch-down), restricted their performance.

The effect of social integration on outcomes after major lower extremity amputation.

PubMed

Hawkins, Alexander T; Pallangyo, Anthony J; Herman, Ayesiga M; Schaumeier, Maria J; Smith, Ann D; Hevelone, Nathanael D; Crandell, David M; Nguyen, Louis L

2016-01-01

Major lower extremity (MLE) amputation is a common procedure that results in a profound change in a patient's life. We sought to determine the association between social support and outcomes after amputation. We hypothesized that patients with greater social support will have better post amputation outcomes. From November 2011 to May 2013, we conducted a cross-sectional, observational, multicenter study. Social integration was measured by the social integration subset of the Short Form Craig Handicap Assessment and Reporting Technique. Systemic social support was assessed by comparing a United States and Tanzanian population. Walking function was measured using the 6-minute walk test and quality of life (QoL) was measured using the EuroQol-5D. We recruited 102 MLE amputees. Sixty-three patients were enrolled in the United States with a mean age of 58.0. Forty-two (67%) were male. Patients with low social integration were more likely to be unable to ambulate (no walk 39% vs slow walk 23% vs fast walk 10%; P = .01) and those with high social integration were more likely to be fast walkers (no walk 10% vs slow walk 59% vs fast walk 74%; P = .01). This relationship persisted in a multivariable analysis. Increasing social integration scores were also positively associated with increasing QoL scores in a multivariable analysis (β, .002; standard error, 0.0008; P = .02). In comparing the United States population with the Tanzanian cohort (39 subjects), there were no differences between functional or QoL outcomes in the systemic social support analysis. In the United States population, increased social integration is associated with both improved function and QoL outcomes among MLE amputees. Systemic social support, as measured by comparing the United States population with a Tanzanian population, was not associated with improved function or QoL outcomes. In the United States, steps should be taken to identify and aid amputees with poor social integration. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

The Effect of Social Integration on Outcomes after Major Lower Extremity Amputation

PubMed Central

Hawkins, Alexander T.; Pallangyo, Anthony J.; Herman, Ayesiga M.; Schaumeier, Maria J.; Smith, Ann D.; Hevelone, Nathanael D.; Crandell, David M.; Nguyen, Louis

2016-01-01

Objective Major lower extremity amputation is a common procedure that results in a profound change in a patient's life. We sought to determine the association between social support and outcomes after amputation. We hypothesized that patients with greater social support will have better post amputation outcomes. Methods From November 2011 to May 2013, we conducted a cross-sectional, observational, multicenter study. Social integration was measured by the social integration subset of the Short Form (Craig Handicap Assessment and Reporting Technique (CHART). Systemic social support was assessed by comparing a US and Tanzanian population. Walking function was measured using the 6MWT and quality of life (QoL) was measured using the EQ-5D. Results 102 major lower extremity amputees were recruited. 63 patients were enrolled in the US with a mean age of 58.0. Forty-two (67%) were male. Patients with low social integration were more likely to be unable to ambulate (no walk 39% vs. slow walk 23% vs. fast walk 10%; P=.01) and those with high social integration were more likely to be fast walkers (no walk 10% vs. slow walk 59% vs. fast walk 74%; P=.01). This relationship persisted in a multivariable analysis. Increasing social integration scores were also positively associated with increasing quality of life scores in a multivariable analysis (β .002; SE .0008; P = .02). In comparing the US population with the Tanzanian cohort (39 subjects), there were no significant differences between functional or quality of life outcomes in the systemic social support analysis. Conclusions In the US population, increased social integration is associated with both improved function and quality of life outcomes among major lower extremity amputees. Systemic social support, as measured by comparing the US population with a Tanzanian population, was not associated with improved function or quality of life outcomes. In the US, steps should be taken to identify and aid amputees with poor social integration. PMID:26474508

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

PubMed

Allami, Mostafa; Mousavi, Batool; Masoumi, Mehdi; Modirian, Ehsan; Shojaei, Hadi; Mirsalimi, Fatemeh; Hosseini, Maryam; Pirouzi, Pirouz

2016-01-01

Upper limb amputations are one of the unpleasant war injuries that armed forces are exposed to frequently. The present study aimed to assess the musculoskeletal and peripheral nervous systems in Iraq-Iran war veterans with bilateral upper extremity amputation. The study consisted of taking a history and clinical examinations including demographic data, presence and location of pain, level of amputation, passive and active ranges of movement of the joints across the upper and lower extremities and spine, manual palpation, neurological examination, blood circulation pulses and issues related to a prosthetic limb. In this study, 103 Iranian bilateral upper extremity amputees (206 amputations) from the Iran-Iraq war were evaluated, and a detailed questionnaire was also administered. The most common level of amputation was the finger or wrist level (108, 52.4 %). Based on clinical examination, we found high frequencies of limited active and passive joint range of movement across the scapula, shoulder, elbow, wrist and metacarpophalangeal, interphalangeal and thumb joints. Based on muscle strength testing, we found varying degrees of weakness across the upper limbs. Musculoskeletal disorders included epicondylitis (65, 31.6 %), rotator cuff injury (24, 11.7 %), bicipital tendonitis (69, 33.5 %), shoulder drop (42, 20.4 %) and muscle atrophy (19, 9.2 %). Peripheral nerve disorders included carpal tunnel syndrome in 13 (6.3 %) and unilateral brachial plexus injury in 1 (1 %). Fifty-three (51.5 %) were diagnosed with facet joint syndrome at the level of the cervical spine (the most frequent site). Using a prosthesis was reported by 65 (63.1 %), both left and right sides. The back was the most common site of pain (71.8 %). The high prevalence of neuro-musculoskeletal disorders among bilateral upper extremity amputees indicates that they need regular rehabilitation care.

Using Wearable Sensors and Machine Learning Models to Separate Functional Upper Extremity Use From Walking-Associated Arm Movements.

PubMed

McLeod, Adam; Bochniewicz, Elaine M; Lum, Peter S; Holley, Rahsaan J; Emmer, Geoff; Dromerick, Alexander W

2016-02-01

To improve measurement of upper extremity (UE) use in the community by evaluating the feasibility of using body-worn sensor data and machine learning models to distinguish productive prehensile and bimanual UE activity use from extraneous movements associated with walking. Comparison of machine learning classification models with criterion standard of manually scored videos of performance in UE prosthesis users. Rehabilitation hospital training apartment. Convenience sample of UE prosthesis users (n=5) and controls (n=13) similar in age and hand dominance (N=18). Participants were filmed executing a series of functional activities; a trained observer annotated each frame to indicate either UE movement directed at functional activity or walking. Synchronized data from an inertial sensor attached to the dominant wrist were similarly classified as indicating either a functional use or walking. These data were used to train 3 classification models to predict the functional versus walking state given the associated sensor information. Models were trained over 4 trials: on UE amputees and controls and both within subject and across subject. Model performance was also examined with and without preprocessing (centering) in the across-subject trials. Percent correct classification. With the exception of the amputee/across-subject trial, at least 1 model classified >95% of test data correctly for all trial types. The top performer in the amputee/across-subject trial classified 85% of test examples correctly. We have demonstrated that computationally lightweight classification models can use inertial data collected from wrist-worn sensors to reliably distinguish prosthetic UE movements during functional use from walking-associated movement. This approach has promise in objectively measuring real-world UE use of prosthetic limbs and may be helpful in clinical trials and in measuring response to treatment of other UE pathologies. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Three-dimensional-printed upper limb prosthesis for a child with traumatic amputation of right wrist: A case report.

PubMed

Xu, Guisheng; Gao, Liang; Tao, Ke; Wan, Shengxiang; Lin, Yuning; Xiong, Ao; Kang, Bin; Zeng, Hui

2017-12-01

For traumatic upper limb amputees, the prohibitive cost of a custom-made prosthesis brings an insufferable financial burden for their families in developing countries. Three-dimensional (3D) printing allows for creating affordable, lightweight, customized, and well-fitting prosthesis, especially for the growing children. We presented a case of an 8-year-old boy, who suffered a traumatic right wrist amputation as result of a mincing machine accident. The patient was immediately sent to the emergency orthopedics department after the accident. He was diagnosed as severed mangled limb crash injury at the level of the right wrist with a Mangled Extremity Severity Score of 8. A wrist disarticulation was performed and a 3D-printed prosthetic hand was designed and manufactured for this child. A personalized prosthetic rehabilitation training was applied after the prosthesis installation at 6 months postoperatively. The function of the prosthesis was evaluated at 1-month and 3-month follow-up using the Children Amputee Prosthetics Projects (CAPP) score and the University Of New Brunswick Test Of Prosthetic Function for Unilateral Amputees (UNB test). The materials cost <20 dollars. The printing took <8 hours and the component assembling was completed within 20 minutes. During the 3-month follow-up, the child's parents were satisfied with the prosthesis and the UNB test showed the significantly improved function of the prosthesis. This novel 3D-printed upper limb prosthesis in a child with the traumatic wrist amputation might serve as a practical and affordable alternative for children in developing countries and those lacking access to health care providers. A personalized prosthetic rehabilitation needs to be undertaken and more clinical studies are warranted to validate the potential superiority of similar 3D-printed prostheses. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

Towards Efficient Decoding of Multiple Classes of Motor Imagery Limb Movements Based on EEG Spectral and Time Domain Descriptors.

PubMed

Samuel, Oluwarotimi Williams; Geng, Yanjuan; Li, Xiangxin; Li, Guanglin

2017-10-28

To control multiple degrees of freedom (MDoF) upper limb prostheses, pattern recognition (PR) of electromyogram (EMG) signals has been successfully applied. This technique requires amputees to provide sufficient EMG signals to decode their limb movement intentions (LMIs). However, amputees with neuromuscular disorder/high level amputation often cannot provide sufficient EMG control signals, and thus the applicability of the EMG-PR technique is limited especially to this category of amputees. As an alternative approach, electroencephalograph (EEG) signals recorded non-invasively from the brain have been utilized to decode the LMIs of humans. However, most of the existing EEG based limb movement decoding methods primarily focus on identifying limited classes of upper limb movements. In addition, investigation on EEG feature extraction methods for the decoding of multiple classes of LMIs has rarely been considered. Therefore, 32 EEG feature extraction methods (including 12 spectral domain descriptors (SDDs) and 20 time domain descriptors (TDDs)) were used to decode multiple classes of motor imagery patterns associated with different upper limb movements based on 64-channel EEG recordings. From the obtained experimental results, the best individual TDD achieved an accuracy of 67.05 ± 3.12% as against 87.03 ± 2.26% for the best SDD. By applying a linear feature combination technique, an optimal set of combined TDDs recorded an average accuracy of 90.68% while that of the SDDs achieved an accuracy of 99.55% which were significantly higher than those of the individual TDD and SDD at p < 0.05. Our findings suggest that optimal feature set combination would yield a relatively high decoding accuracy that may improve the clinical robustness of MDoF neuroprosthesis. The study was approved by the ethics committee of Institutional Review Board of Shenzhen Institutes of Advanced Technology, and the reference number is SIAT-IRB-150515-H0077.

Toward attenuating the impact of arm positions on electromyography pattern-recognition based motion classification in transradial amputees

PubMed Central

2012-01-01

Background Electromyography (EMG) pattern-recognition based control strategies for multifunctional myoelectric prosthesis systems have been studied commonly in a controlled laboratory setting. Before these myoelectric prosthesis systems are clinically viable, it will be necessary to assess the effect of some disparities between the ideal laboratory setting and practical use on the control performance. One important obstacle is the impact of arm position variation that causes the changes of EMG pattern when performing identical motions in different arm positions. This study aimed to investigate the impacts of arm position variation on EMG pattern-recognition based motion classification in upper-limb amputees and the solutions for reducing these impacts. Methods With five unilateral transradial (TR) amputees, the EMG signals and tri-axial accelerometer mechanomyography (ACC-MMG) signals were simultaneously collected from both amputated and intact arms when performing six classes of arm and hand movements in each of five arm positions that were considered in the study. The effect of the arm position changes was estimated in terms of motion classification error and compared between amputated and intact arms. Then the performance of three proposed methods in attenuating the impact of arm positions was evaluated. Results With EMG signals, the average intra-position and inter-position classification errors across all five arm positions and five subjects were around 7.3% and 29.9% from amputated arms, respectively, about 1.0% and 10% low in comparison with those from intact arms. While ACC-MMG signals could yield a similar intra-position classification error (9.9%) as EMG, they had much higher inter-position classification error with an average value of 81.1% over the arm positions and the subjects. When the EMG data from all five arm positions were involved in the training set, the average classification error reached a value of around 10.8% for amputated arms. Using a two-stage cascade classifier, the average classification error was around 9.0% over all five arm positions. Reducing ACC-MMG channels from 8 to 2 only increased the average position classification error across all five arm positions from 0.7% to 1.0% in amputated arms. Conclusions The performance of EMG pattern-recognition based method in classifying movements strongly depends on arm positions. This dependency is a little stronger in intact arm than in amputated arm, which suggests that the investigations associated with practical use of a myoelectric prosthesis should use the limb amputees as subjects instead of using able-body subjects. The two-stage cascade classifier mode with ACC-MMG for limb position identification and EMG for limb motion classification may be a promising way to reduce the effect of limb position variation on classification performance. PMID:23036049

Capability Enhancement and Amputee Care in Operation Iraqi Freedom: The Role of a Rehabilitation and Prosthetics Assistance Team in Reconstruction Operations

DTIC Science & Technology

2009-05-01

School of Medicine. HH) Penn Street. Allied Heaith Btiilding. Baltimm-e.MD 21201- 1082 , Previous Présentations: Related material was presented in abbrevi...Rehabilitation Science,University of Maryland School of Medicine,100 Penn Street. Allied Heaith Btiilding,Baltimore ,MD,21201- 1082 8. PERFORMING

Initial Evaluation of the Dermoskeleton Concept: Application of Biomechatronics and Artificial Intelligence to Address the Soldiers Overload Challenge

DTIC Science & Technology

2011-05-01

leg prosthesis for above-the-knee amputees currently commercialized by Ossur hf and developed by Victhom Human Bionics Inc., a medical device...did not feel they worked as hard when wearing the K-SRDTM version POC during the loaded conditions. However, based on our heart rate measured, there

Psychological and Educational Studies with Spina Bifida Children. Final Report.

ERIC Educational Resources Information Center

Diller, Leonard; And Others

To measure school achievements in spina bifida children, to relate these measures to certain variables, to obtain information on educational problems, and to study facets of cognition and its changes with age, 77 spina bifida children and 53 amputees (all aged 5 to 15) were tested. Sixty non-disabled children were at times used for controls. The…

Naval Training Equipment Center Index of Technical Reports,

DTIC Science & Technology

1982-09-01

741 RECOMMENDED PROCEDURES AND TRAINING NAVAL TRAINING AIDS. tAMPHIBIOUS OPERATIONS PROCEDURES AND RESEARCH PLANNING AD- 642 590 TRAINING DEVICES FOR...PROCEDURES AND RESEARCH PLANNING OBSERVATION AND FIRE CONTROL WITH FOR ANTI-AIR WARFARE TRAINING SPECIFIC REFERENCE TO THE TRAINING *AMPUTEES PROGRAM...619 AD- 707 757 NAVAL PERSONNEL *COMMUNICATION SATELLITES PROCEDURES AND RESEARCH PLANNING *COMBUSTION PRODUCTS Computer Managed Instruction by FOR

Strength, Pain, Function in OIF/OEF Amputees: A Nurse-Managed Program

DTIC Science & Technology

2014-03-25

resistance training and neuromuscular electrical stimulation in knee osteoarthritis : a randomized controlled trial. BMC Musculoskeletal Disorders, 13, 118... systematic review of the effects of different electromyostimulation methods on selected strength parameters in trained and elite athletes. Journal of...electrical stimulation on rehabilitation after ligament and meniscal injuries: a systematic review . Sao Paulo Medical Journal, 129(6), 414-423

An Analysis of Basic Construction Variables of Racing Wheelchairs Used in the 1984 International Games for the Disabled.

ERIC Educational Resources Information Center

York, Sherril L.; Kimura, Iris F.

1987-01-01

A photographic analysis of racing wheelchairs used by cerebral palsy class four athletes and amputee athletes at the 1984 International Games for the Disabled was undertaken in order to analyze seven wheelchair construction variables in relation to performance outcome, distance raced, and type of disability of the user. (Author/MT)

Bionic Running for Unilateral Transtibial Military Amputees

DTIC Science & Technology

2010-01-01

Bellman, R., 2010, “An Active Ankle-Foot Prosthesis With Biomechanical Energy Regeneration”, Transactions of the ASME Journal...Lefeber, D., 2008, “A Biomechanical Transtibial Prosthesis Powered by Pleated Pneumatic Artificial Muscles,” Model Identification and Control, 4, 394- 405. ...Inc., have designed, built, and demonstrated a first of its kind motor powered, single board computer controlled, running prosthesis for military

Evaluation of the Mangled Extremity Severity Score in Combat-Related Type III Tibia Fracture

DTIC Science & Technology

2014-09-01

Return to duty rates of amputee soldiers in the current conflicts in Afghanistan and Iraq. J Trauma. 2010; 68:1476–1479. 5. Johansen K, Daines M, Howey T...severity score (MESS) in combat related type III tibia fracture. J Orthop Trauma. 2013. 4. Johansen K, Daines M, Howey T, et al. Objective criteria

Incidental Learning and Explicit Recall in Upper Extremity Prosthesis Use: Insights Into Functional Rehabilitation Challenges.

PubMed

Hughey, Laura; Wheaton, Lewis A

2016-01-01

Loss of an upper extremity and the resulting rehabilitation often requires individuals to learn how to use a prosthetic device for activities of daily living. It remains unclear how prostheses affect motor learning outcomes. The authors' aim was to evaluate whether incidental motor learning and explicit recall is affected in intact persons either using prostheses (n = 10) or the sound limb (n = 10), and a chronic amputee on a modified serial reaction time task. Latency and accuracy of task completion were recorded over six blocks, with a distractor task between blocks 5 and 6. Participants were also asked to recall the sequence immediately following the study and at a 24-hr follow-up. Prosthesis users demonstrate patterns consistent with implicit learning, with sustained error patterns with the distal terminal device. More intact individuals were able to explicitly recall the sequence initially, however there was no significant difference 24 hr following the study. Acute incidental motor learning does not appear to diminish task related error patterns or accompany with explicit recall in prosthesis users, which could present limitations for acute training of prosthesis use in amputees. This suggests differing mechanisms of visuospatial sequential learning and motor control with prostheses.

The biomechanical effect of arm mass on long jump performance: A case study of a paralympic upper limb amputee.

PubMed

Pradon, Didier; Mazure-Bonnefoy, Alice; Rabita, Giuseppe; Hutin, Emilie; Zory, Raphael; Slawinski, Jean

2014-06-01

The role of arm motion during the long jump has been well studied. The aim of this study was to quantify the effect of forearm mass on impulse and the kinematics of the flight phase in an upper limb amputee. A world-record paralympic long jumper carried out jumps in three conditions: wearing his usual forearm prosthesis and with 0.3 and 0.4 kg added mass. A motion capture system including force plates was used to record the jump. At take-off, the addition of 0.4 kg to the prosthesis decreased the vertical velocity of the centre of mass but increased horizontal velocity. These modifications were associated with an increase in landing distance and an improvement of the synchronization between arms. Increasing forearm mass appears to improve long jump performance. Further studies need to evaluate the optimal prosthetic mass for both training and competition. This biomechanical analysis of the long jump highlighted the effects of changing prosthesis mass on performance. This methodological approach may be useful in the context of sport and performance research. © The International Society for Prosthetics and Orthotics 2013.

Techniques for Interface Stress Measurements within Prosthetic Sockets of Transtibial Amputees: A Review of the Past 50 Years of Research.

PubMed

Al-Fakih, Ebrahim A; Abu Osman, Noor Azuan; Mahmad Adikan, Faisal Rafiq

2016-07-20

The distribution of interface stresses between the residual limb and prosthetic socket of a transtibial amputee has been considered as a direct indicator of the socket quality fit and comfort. Therefore, researchers have been very interested in quantifying these interface stresses in order to evaluate the extent of any potential damage caused by the socket to the residual limb tissues. During the past 50 years a variety of measurement techniques have been employed in an effort to identify sites of excessive stresses which may lead to skin breakdown, compare stress distributions in various socket designs, and evaluate interface cushioning and suspension systems, among others. The outcomes of such measurement techniques have contributed to improving the design and fitting of transtibial sockets. This article aims to review the operating principles, advantages, and disadvantages of conventional and emerging techniques used for interface stress measurements inside transtibial sockets. It also reviews and discusses the evolution of different socket concepts and interface stress investigations conducted in the past five decades, providing valuable insights into the latest trends in socket designs and the crucial considerations for effective stress measurement tools that lead to a functional prosthetic socket.

Fluctuating residual limb volume accommodated with an adjustable, modular socket design: A novel case report.

PubMed

Mitton, Kay; Kulkarni, Jai; Dunn, Kenneth William; Ung, Anthony Hoang

2017-10-01

This novel case report describes the problems of prescribing a prosthetic socket in a left transfemoral amputee secondary to chronic patellofemoral instability compounded by complex regional pain syndrome. Case Description and Methods: Following the amputation, complex regional pain syndrome symptoms recurred in the residual limb, presenting mainly with oedema. Due to extreme daily volume fluctuations of the residual limb, a conventional, laminated thermoplastic socket fitting was not feasible. Findings and Outcomes: An adjustable, modular socket design was trialled. The residual limb volume fluctuations were accommodated within the socket. Amputee rehabilitation could be continued, and the rehabilitation goals were achieved. The patient was able to wear the prosthesis for 8 h daily and to walk unaided indoors and outdoors. An adjustable, modular socket design accommodated the daily residual limb volume fluctuations and provided a successful outcome in this case. It demonstrates the complexities of socket fitting and design with volume fluctuations. Clinical relevance Ongoing complex regional pain syndrome symptoms within the residual limb can lead to fitting difficulties in a conventional, laminated thermoplastic socket due to volume fluctuations. An adjustable, modular socket design can accommodate this and provide a successful outcome.

Techniques for Interface Stress Measurements within Prosthetic Sockets of Transtibial Amputees: A Review of the Past 50 Years of Research

PubMed Central

Al-Fakih, Ebrahim A.; Abu Osman, Noor Azuan; Mahmad Adikan, Faisal Rafiq

2016-01-01

The distribution of interface stresses between the residual limb and prosthetic socket of a transtibial amputee has been considered as a direct indicator of the socket quality fit and comfort. Therefore, researchers have been very interested in quantifying these interface stresses in order to evaluate the extent of any potential damage caused by the socket to the residual limb tissues. During the past 50 years a variety of measurement techniques have been employed in an effort to identify sites of excessive stresses which may lead to skin breakdown, compare stress distributions in various socket designs, and evaluate interface cushioning and suspension systems, among others. The outcomes of such measurement techniques have contributed to improving the design and fitting of transtibial sockets. This article aims to review the operating principles, advantages, and disadvantages of conventional and emerging techniques used for interface stress measurements inside transtibial sockets. It also reviews and discusses the evolution of different socket concepts and interface stress investigations conducted in the past five decades, providing valuable insights into the latest trends in socket designs and the crucial considerations for effective stress measurement tools that lead to a functional prosthetic socket. PMID:27447646

Quantitative assessment of four men using above-elbow prosthetic control.

PubMed

Popat, R A; Krebs, D E; Mansfield, J; Russell, D; Clancy, E; Gill-Body, K M; Hogan, N

1993-07-01

We studied the relationship between kinematically unconstrained activities of daily living (ADL) tasks and a kinematically constrained task in above-elbow (AE) amputee subjects using myoelectrically controlled prostheses. Four men, 24 to 49 years old, with unilateral AE amputation wore a prosthesis interfaced to a programmable controller to emulate two different elbow control schemes, conventional velocity and a new "natural" controller. Subjects were timed during three ADL tasks--cutting meat, donning socks, and rolling dough--with both controllers. The prosthesis emulator was then connected to a crank device with a handle, and the subjects turned the crank from bottom to top positions in a vertical plane using each controller. Synergistic shoulder-elbow joint coordination required for crank turning was quantified as the maximum slope of the change in elbow torque versus the change in crank-angle. Performance between the two controllers differed significantly for the crank test but not for ADL tasks. One subject did not complete all crank turning tests. Positive canonical correlation of 0.77 was found between time and crank domain measures. We conclude that biomechanical assessments should be integrated with time-based clinical tests to comprehensively evaluate performance of AE amputee subjects with a myoelectric device.

Evaluation of a new geriatric foot versus the Solid Ankle Cushion Heel foot for low-activity amputees.

PubMed

Bonnet, Xavier; Adde, Jean N; Blanchard, François; Gedouin-Toquet, Annick; Eveno, Dominique

2015-04-01

It is always a challenge to rehabilitate geriatric amputees to perform self-care skills at home with limited ambulation. A new geriatric foot (with a lower effective foot length) has been specifically designed to reduce residual limb stress and to ease the step completion. The aim of this study is to evaluate the benefit of a new geriatric foot versus a Solid Ankle Cushion Heel foot for low-activity persons with transtibial amputation. Crossover study. A total of 12 patients were included in this study. 2-min walking test, Quebec User Evaluation of Satisfaction with Assistive Technology 2.0 questionnaire and pressure socket measurements. The geriatric foot allows for greater patient satisfaction. The maximal pressure was significantly lower in the proximal anterior stump area. No statistical differences were obtained from the 2-min walking test. A geriatric foot designed with a low effective foot length improves the satisfaction and reduces proximal anterior socket pressures for poor-performing persons with transtibial amputation. The development and evaluation of feet specifically designed for geriatric persons with transtibial amputation could improve their specific requirements and satisfaction. © The International Society for Prosthetics and Orthotics 2014.

Where is hidden the ghost in phantom sensations?

PubMed Central

Buonocore, Michelangelo

2015-01-01

The term phantom sensations (PS) refers to sensations in a missing body part. They are almost universal in amputees and can be both painful and not painful. Although PS have been frequently described in limb amputees, they can also occur in other clinical conditions and several pathophysiological interpretations have been proposed, with a predominance of theories based on a central origin. Actually, different mechanisms are able to create a phantom sensation. After an amputation, PS are frequently generated by the genesis of ectopic action potentials in the interrupted nerve fibers but the PS generator can also be more proximal. Sometimes PS are not created by the stimulation of somatosensory fibers with a missing territory, but they can be the result of central sensitization or neuroplastic changes that allow for the convergence of impulses coming from different body parts (referred sensations), one of which is missing. In conclusion, PS can be generated by both neuropathic and non-neuropathic mechanisms developed in the amputated body part or in other parts of the nervous system. Since these mechanisms are not pathognomonic of amputation there are no hidden ghosts to look for in phantom sensations. The only interpretative rule is just to follow the pathophysiological principles. PMID:26244147

Development of a prosthesis shoulder mechanism for upper limb amputees: application of an original design methodology to optimize functionality and wearability.

PubMed

Troncossi, Marco; Borghi, Corrado; Chiossi, Marco; Davalli, Angelo; Parenti-Castelli, Vincenzo

2009-05-01

The application of a design methodology for the determination of the optimal prosthesis architecture for a given upper limb amputee is presented in this paper along with the discussion of its results. In particular, a novel procedure was used to provide the main guidelines for the design of an actuated shoulder articulation for externally powered prostheses. The topology and the geometry of the new articulation were determined as the optimal compromise between wearability (for the ease of use and the patient's comfort) and functionality of the device (in terms of mobility, velocity, payload, etc.). This choice was based on kinematic and kinetostatic analyses of different upper limb prosthesis models and on purpose-built indices that were set up to evaluate the models from different viewpoints. Only 12 of the 31 simulated prostheses proved a sufficient level of functionality: among these, the optimal solution was an articulation having two actuated revolute joints with orthogonal axes for the elevation of the upper arm in any vertical plane and a frictional joint for the passive adjustment of the humeral intra-extra rotation. A prototype of the mechanism is at the clinical test stage.

Rehabilitation after amputation: psychotherapeutic intervention module in Indian scenario.

PubMed

Srivastava, Kalpana; Chaudhury, Suprakash

2014-01-01

Psychological aspects of adjustment to amputation are varied and not addressed in the present treatment regime. There is no research evidence available of psychological intervention and outcome in Indian scenario. One hundred and seventy-three consecutive patients with limb amputations were randomly assigned to psychotherapeutic intervention module (PIM, study group) (n = 90) and treatment as usual group (TAU, control group) (n = 83). Patients with psychotic disorder were excluded from the study. Carroll Rating Scale for Depression (CRSD), State-Trait Anxiety Inventory (STAI), Amputees Body Image Scale (ABIS), and Impact of Event Scale (IES) along with specially designed information schedule were administered individually. Structured psychotherapeutic module was developed for the intervention. Patients in PIM group were given six therapy sessions, addressing the specific areas of concern. All patients were evaluated on the same tools after two months of therapy. Analysis showed that after treatment a significant reduction in scores was noted on CRSD, STAI, ABIS, and IES in the PIM group. On the TAU group a significant reduction was seen only in the ABIS. The psychological intervention module proposed by authors was efficacious in alleviating the psychological distress, depression, and anxiety and thus was vastly superior to the conventional method of management of amputees.

Short- and Long-Term Learning of Feedforward Control of a Myoelectric Prosthesis with Sensory Feedback by Amputees.

PubMed

Strbac, Matija; Isakovic, Milica; Belic, Minja; Popovic, Igor; Simanic, Igor; Farina, Dario; Keller, Thierry; Dosen, Strahinja

2017-11-01

Human motor control relies on a combination of feedback and feedforward strategies. The aim of this study was to longitudinally investigate artificial somatosensory feedback and feedforward control in the context of grasping with myoelectric prosthesis. Nine amputee subjects performed routine grasping trials, with the aim to produce four levels of force during four blocks of 60 trials across five days. The electrotactile force feedback was provided in the second and third block using multipad electrode and spatial coding. The first baseline and last validation block (open-loop control) evaluated the effects of long- (across sessions) and short-term (within session) learning, respectively. The outcome measures were the absolute error between the generated and target force, and the number of force saturations. The results demonstrated that the electrotactile feedback improved the performance both within and across sessions. In the validation block, the performance did not significantly decrease and the quality of open-loop control (baseline) improved across days, converging to the performance characterizing closed-loop control. This paper provides important insights into the feedback and feedforward processes in prosthesis control, contributing to the better understanding of the role and design of feedback in prosthetic systems.

Neuromechanical sensor fusion yields highest accuracies in predicting ambulation mode transitions for trans-tibial amputees.

PubMed

Tkach, D C; Hargrove, L J

2013-01-01

Advances in battery and actuator technology have enabled clinical use of powered lower limb prostheses such as the BiOM Powered Ankle. To allow ambulation over various types of terrains, such devices rely on built-in mechanical sensors or manual actuation by the amputee to transition into an operational mode that is suitable for a given terrain. It is unclear if mechanical sensors alone can accurately modulate operational modes while voluntary actuation prevents seamless, naturalistic gait. Ensuring that the prosthesis is ready to accommodate new terrain types at first step is critical for user safety. EMG signals from patient's residual leg muscles may provide additional information to accurately choose the proper mode of prosthesis operation. Using a pattern recognition classifier we compared the accuracy of predicting 8 different mode transitions based on (1) prosthesis mechanical sensor output (2) EMG recorded from residual limb and (3) fusion of EMG and mechanical sensor data. Our findings indicate that the neuromechanical sensor fusion significantly decreases errors in predicting 10 mode transitions as compared to using either mechanical sensors or EMG alone (2.3±0.7% vs. 7.8±0.9% and 20.2±2.0% respectively).

How Depressive Levels Are Related to the Adults' Experiences of Lower-Limb Amputation: A Mixed Methods Pilot Study

ERIC Educational Resources Information Center

Senra, Hugo

2013-01-01

The current pilot study aims to explore whether different adults' experiences of lower-limb amputation could be associated with different levels of depression. To achieve these study objectives, a convergent parallel mixed methods design was used in a convenience sample of 42 adult amputees (mean age of 61 years; SD = 13.5). All of them had…

Studies in Reaction to Disability. XII: Structure of Attitudes toward the Physically Disabled; Disability Factor Scales--Amputation, Blindness, Cosmetic Conditions.

ERIC Educational Resources Information Center

Siller, Jerome; And Others

To describe and to develop instruments to measure attitudes toward amputees, the blind, and those with cosmetic conditions, three groups of subjects responded to one of three large pools of items tapping attitudes toward the three disability conditions. Three new groups of about 500 subjects of diverse demographic characteristics were given one of…

The bizarre request for amputation.

PubMed

Barnes, Rachel

2011-12-01

Apotemnophilia is a condition where sufferers wish to be an amputee. Currently, belief in the medical profession is that it is part of the spectrum of body dysmorphic disorder and as such patients are denied surgical correction. This can lead sufferers to extreme lengths. Proponents seek to have the disorder reclassified to a body identity integrity disorder such as gender identity disorder. In this way treatment modalities could be reassessed.

Glasgow Coma Scale Scores, Early Opioids, and 4-year Psychological Outcomes among Combat Amputees

DTIC Science & Technology

2014-01-01

psychological outcomes, loss of consciousness, military and VA health data, morphine , posttraumatic stress disorder, traumatic brain injury. INTRODUCTION...appropriate for postinjury analgesia [15–17]. Unfortu- nately, little research has compared the psychological benefits of morphine or fentanyl...that morphine reduced PTSD compared with fentanyl because mor- phine produced more long-lasting pain relief and/or was more effective at blocking

Determining Clinically Relevant Changes in Community Walking Metrics to Be Tracked by the VA as Part of Routine Care in Lower Limb Amputee Veterans

DTIC Science & Technology

2016-10-01

total of 52 subjects have enrolled in the study: Veteran subjects n=34 and University of Utah subjects n= 18 . Preliminary analysis indicates that daily...relevant change 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18 . NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON USAMRMC a. REPORT

Walking speed related joint kinetic alterations in trans-tibial amputees: impact of hydraulic 'ankle' damping.

PubMed

De Asha, Alan R; Munjal, Ramesh; Kulkarni, Jai; Buckley, John G

2013-10-17

Passive prosthetic devices are set up to provide optimal function at customary walking speed and thus may function less effectively at other speeds. This partly explains why joint kinetic adaptations become more apparent in lower-limb amputees when walking at speeds other than customary. The present study determined whether a trans-tibial prosthesis incorporating a dynamic-response foot that was attached to the shank via an articulating hydraulic device (hyA-F) lessened speed-related adaptations in joint kinetics compared to when the foot was attached via a rigid, non-articulating attachment (rigF). Eight active unilateral trans-tibial amputees completed walking trials at their customary walking speed, and at speeds they deemed to be slow-comfortable and fast-comfortable whilst using each type of foot attachment. Moments and powers at the distal end of the prosthetic shank and at the intact joints of both limbs were compared between attachment conditions. There was no change in the amount of intact-limb ankle work across speed or attachment conditions. As speed level increased there was an increase on both limbs in the amount of hip and knee joint work done, and increases on the prosthetic side were greater when using the hyA-F. However, because all walking speed levels were higher when using the hyA-F, the intact-limb ankle and combined joints work per meter travelled were significantly lower; particularly so at the customary speed level. This was the case despite the hyA-F dissipating more energy during stance. In addition, the amount of eccentric work done per meter travelled became increased at the residual knee when using the hyA-F, with increases again greatest at customary speed. Findings indicate that a trans-tibial prosthesis incorporating a dynamic-response foot reduced speed-related changes in compensatory intact-limb joint kinetics when the foot was attached via an articulating hydraulic device compared to rigid attachment. As differences between attachment conditions were greatest at customary speed, findings indicate a hydraulic ankle-foot device is most effectual at the speed it is set-up for.

“Pulling Telescoped Phantoms Out of the Stump”: Manipulating the Perceived Position of Phantom Limbs Using a Full-Body Illusion

PubMed Central

Schmalzl, Laura; Thomke, Erik; Ragnö, Christina; Nilseryd, Maria; Stockselius, Anita; Ehrsson, H. Henrik

2011-01-01

Most amputees experience phantom limbs, or the sensation that their amputated limb is still attached to the body. Phantom limbs can be perceived in the location previously occupied by the intact limb, or they can gradually retract inside the stump, a phenomenon referred to as “telescoping”.  Telescoping is relevant from a clinical point of view, as it tends to be related to increased levels of phantom pain. In the current study we demonstrate how a full-body illusion can be used to temporarily revoke telescoping sensations in upper limb amputees. During this illusion participants view the body of a mannequin from a first person perspective while being subjected to synchronized visuo-tactile stimulation through stroking, which makes them experience the mannequin’s body as their own. In Experiment 1 we used an intact mannequin, and showed that amputees can experience ownership of an intact body as well as referral of touch from both hands of the mannequin. In Experiment 2 and 3 we used an amputated mannequin, and demonstrated that depending on the spatial location of the strokes applied to the mannequin, participants experienced their phantom hand to either remain telescoped, or to actually be located below the stump. The effects were supported by subjective data from questionnaires, as well as verbal reports of the perceived location of the phantom hand in a visual judgment task. These findings are of particular interest, as they show that the temporary revoking of telescoping sensations does not necessarily have to involve the visualization of an intact hand or illusory movement of the phantom (as in the rubber hand illusion or mirror visual feedback therapy), but that it can also be obtained through mere referral of touch from the stump to the spatial location corresponding to that previously occupied by the intact hand. Moreover, our study also provides preliminary evidence for the fact that these manipulations can have an effect on phantom pain sensations. PMID:22065956

Exercise intervention for unilateral amputees with low back pain: study protocol for a randomised, controlled trial.

PubMed

Wasser, Joseph G; Herman, Daniel C; Horodyski, MaryBeth; Zaremski, Jason L; Tripp, Brady; Page, Phillip; Vincent, Kevin R; Vincent, Heather K

2017-12-29

Atraumatic lower limb amputation is a life-changing event for approximately 185,000 persons in the United States each year. A unilateral amputation is associated with rapid changes to the musculoskeletal system including leg and back muscle atrophy, strength loss, gait asymmetries, differential mechanical joint loading and leg length discrepancies. Even with high-quality medical care and prostheses, amputees still develop secondary musculoskeletal conditions such as chronic low back pain (LBP). Resistance training interventions that focus on core stabilization, lumbar strength and dynamic stability during loading have strong potential to reduce LBP and address amputation-related changes to the musculoskeletal system. Home-based resistance exercise programs may be attractive to patients to minimize travel and financial burdens. This study will be a single-assessor-blinded, pre-post-test randomised controlled trial involving 40 men and women aged 18-60 years with traumatic, unilateral transtibial amputation. Participants will be randomised to a home-based, resistance exercise group (HBRX) or a wait-list control group (CON). The HBRX will consist of 12 weeks of elastic resistance band and bodyweight training to improve core and lumbopelvic strength. Participants will be monitored via Skype or Facetime on a weekly basis. The primary outcome will be pain severity (11-point Numerical Pain Rating Scale; NRS pain ). Secondary outcomes will include pain impact on quality of life (Medical Outcomes Short Form 36, Oswestry Disability Index and Roland Morris Disability Questionnaire), kinematics and kinetics of walking gait on an instrumented treadmill, muscle morphology (muscle thickness of multifidus, transversus abdominis, internal oblique), maximal muscle strength of key lumbar and core muscles, and daily step count. The study findings will determine whether a HBRX program can decrease pain severity and positively impact several physiological and mechanical factors that contribute to back pain in unilateral transtibial amputees with chronic LBP. We will determine the relative contribution of the exercise-induced changes in these factors on pain responsiveness in this population. ClinicalTrials.gov, ID: NCT03300375 . Registered on 2 October 2017.

A Multi-Class Proportional Myocontrol Algorithm for Upper Limb Prosthesis Control: Validation in Real-Life Scenarios on Amputees.

PubMed

Amsuess, Sebastian; Goebel, Peter; Graimann, Bernhard; Farina, Dario

2015-09-01

Functional replacement of upper limbs by means of dexterous prosthetic devices remains a technological challenge. While the mechanical design of prosthetic hands has advanced rapidly, the human-machine interfacing and the control strategies needed for the activation of multiple degrees of freedom are not reliable enough for restoring hand function successfully. Machine learning methods capable of inferring the user intent from EMG signals generated by the activation of the remnant muscles are regarded as a promising solution to this problem. However, the lack of robustness of the current methods impedes their routine clinical application. In this study, we propose a novel algorithm for controlling multiple degrees of freedom sequentially, inherently proportionally and with high robustness, allowing a good level of prosthetic hand function. The control algorithm is based on the spatial linear combinations of amplitude-related EMG signal features. The weighting coefficients in this combination are derived from the optimization criterion of the common spatial patterns filters which allow for maximal discriminability between movements. An important component of the study is the validation of the method which was performed on both able-bodied and amputee subjects who used physical prostheses with customized sockets and performed three standardized functional tests mimicking daily-life activities of varying difficulty. Moreover, the new method was compared in the same conditions with one clinical/industrial and one academic state-of-the-art method. The novel algorithm outperformed significantly the state-of-the-art techniques in both subject groups for tests that required the activation of more than one degree of freedom. Because of the evaluation in real time control on both able-bodied subjects and final users (amputees) wearing physical prostheses, the results obtained allow for the direct extrapolation of the benefits of the proposed method for the end users. In conclusion, the method proposed and validated in real-life use scenarios, allows the practical usability of multifunctional hand prostheses in an intuitive way, with significant advantages with respect to previous systems.

Long-term follow-up study of bilateral above-the-knee amputees from the Vietnam War.

PubMed

Dougherty, P J

1999-10-01

Because caring for patients who have combat-related amputations is a discontinuous practice, military surgeons must relearn treatment techniques during each conflict. The purpose of the present long-term study (average duration of follow-up, 27.5 years) was to document the status of patients who had sustained a bilateral above-the-knee amputation in Vietnam and had been managed by the only separate amputee service in the United States Army. A review of the records of 484 battle amputees identified thirty individuals (6 percent) who had a bilateral above-the-knee amputation. Twenty-six (87 percent) of the thirty patients had been injured by a land mine or a booby trap. Fifty-three (88 percent) of the sixty limbs were amputated because of trauma, and the other seven (12 percent) were amputated secondarily because of infection. Data regarding education, employment, marriage and family life, prosthetic use, and psychological care were collected by mail or telephone for twenty-three (85 percent) of the twenty-seven surviving patients. Respondents also completed the Short Form-36 (SF-36) Health Survey. At the time of the study, five (22 percent) of the twenty-three respondents used prostheses for walking; the devices were used for an average of 7.7 hours per day. Sixteen respondents (70 percent) were or had been employed outside of the home since the time of discharge. The physical functioning score on the SF-36 questionnaire was significantly lower for the study group than it was for a group of age and gender-matched controls (p < 0.001; Student two-tailed t test). With the numbers available, no significant differences could be detected between the groups with regard to physical role functioning (p = 0.377), bodily pain (p = 0.603), general health (p = 0.407), vitality (p = 0.949), social functioning (p = 0.460), emotional role functioning (p = 0.029), or mental health (p = 0.102). The patients in the present study have led relatively normal, productive lives within the context of their physical limitations.

Multisession, noninvasive closed-loop neuroprosthetic control of grasping by upper limb amputees.

PubMed

Agashe, H A; Paek, A Y; Contreras-Vidal, J L

2016-01-01

Upper limb amputation results in a severe reduction in the quality of life of affected individuals due to their inability to easily perform activities of daily living. Brain-machine interfaces (BMIs) that translate grasping intent from the brain's neural activity into prosthetic control may increase the level of natural control currently available in myoelectric prostheses. Current BMI techniques demonstrate accurate arm position and single degree-of-freedom grasp control but are invasive and require daily recalibration. In this study we tested if transradial amputees (A1 and A2) could control grasp preshaping in a prosthetic device using a noninvasive electroencephalography (EEG)-based closed-loop BMI system. Participants attempted to grasp presented objects by controlling two grasping synergies, in 12 sessions performed over 5 weeks. Prior to closed-loop control, the first six sessions included a decoder calibration phase using action observation by the participants; thereafter, the decoder was fixed to examine neuroprosthetic performance in the absence of decoder recalibration. Ability of participants to control the prosthetic was measured by the success rate of grasping; ie, the percentage of trials within a session in which presented objects were successfully grasped. Participant A1 maintained a steady success rate (63±3%) across sessions (significantly above chance [41±5%] for 11 sessions). Participant A2, who was under the influence of pharmacological treatment for depression, hormone imbalance, pain management (for phantom pain as well as shoulder joint inflammation), and drug dependence, achieved a success rate of 32±2% across sessions (significantly above chance [27±5%] in only two sessions). EEG signal quality was stable across sessions, but the decoders created during the first six sessions showed variation, indicating EEG features relevant to decoding at a smaller timescale (100ms) may not be stable. Overall, our results show that (a) an EEG-based BMI for grasping is a feasible strategy for further investigation of prosthetic control by amputees, and (b) factors that may affect brain activity such as medication need further examination to improve accuracy and stability of BMI performance. © 2016 Elsevier B.V. All rights reserved.

Perspiration Thresholds and Secure Suspension for Lower Limb Amputees in Demanding Environments

DTIC Science & Technology

2016-10-01

first five participants (49±12 yo , 93±14 kg, 1.82±0.06 m, 19±15 years post-amputation, n= 4 trauma, n=1 secondary to infection). All were fit a...TYPE Annual 3. DATES COVERED 30Sep2015 – 29Sep2016 4 . TITLE AND SUBTITLE 5a. CONTRACT NUMBER Perspiration Thresholds and Secure Suspension for Lower...1 4 . IMPACT

Cybernetic prosthesis

NASA Technical Reports Server (NTRS)

Mann, R. W.

1974-01-01

Design and development of a prosthetic device fitted to an above elbow amputee is reported that derives control information from the human to modulate power to an actuator to drive the substitute limb. In turn, the artificial limb generates sensory information feedback to the human nervous system and brain. This synergetic unity feeds efferent or motor control information from the human to the machine, and the machine responds, delivering afferent or sensory information back to the man.

Glasgow Coma Scores, Early Opioids, and Posttraumatic Stress Disorder Among Combat Amputees

DTIC Science & Technology

2014-04-01

icz, Johnson, & Mosely, 2008). Little research has compared how morphine and fentanyl might impact later psychological outcomes such as PTSD. In the...Fox, Saunders, Menk, & Middaugh, 1995). Because the analgesic effect of fentanyl is approximately 100 times more than morphine , the median Level 2...dosages administered to patients for these opioids appeared equivalent for analgesic effectiveness (Fox et al., 1995). Of the morphine -treated pa

Development of Osseointegrated Implants for Soldier Amputees Following Orthopaedic Extremity Trauma

DTIC Science & Technology

2007-08-01

bone fracture. The first year of research focused on determining morphometric variations in the internal structure of the human femur as a function...hypotheses the research will determine morphometric variations in the internal structure of the human femur as a function of gender, age, and ethnic...QUARTER 1): To perform the sizing studies for the sheep implants an IACUC exempt morphometric study was conducted using cadaveric sheep

Development of Osseointegrated Implants for Soldier Amputees Following Orthopaedic Extremity Trauma

DTIC Science & Technology

2008-08-01

specimens, histology and mechanical testing of implants. The second focus of Year 2 was human morphometric studies on variations due to ethnicity, gender...custom implants in above-knee patients with amputations would require expensive custom type implants, a morphometric study was conducted on human...male and female cadaveric femurs. Morphometric variations of the periosteal surface of long bones have been identified with changing age, gender and

Improved Training Method for Rapid Rehabilitation of Amputees

DTIC Science & Technology

2015-05-01

Falls Overall Project Summary This report describes a four year research effort to develop and test a novel training technique aimed at increasing...month post training assessment. One subject moved after completing the training and did not return for follow-up. Three subjects failed to respond to...training (n=5) Reasons: Moved, revisions, suicide attempt, time conflict Completed Training (n= 20) Completed post - testing (n=20). Lost to

Prosthetic Hand With Two Gripping Fingers

NASA Technical Reports Server (NTRS)

Norton, William E.; Belcher, Jewell B.; Vest, Thomas W.; Carden, James R.

1993-01-01

Prosthetic hand developed for amputee who retains significant portion of forearm. Outer end of device is end effector including two fingers, one moved by rotating remaining part of forearm about its longitudinal axis. Main body of end effector is end member supporting fingers, roller bearing assembly, and rack-and-pinion mechanism. Advantage of rack-and-pinion mechanism enables user to open or close gap between fingers with precision and force.

Studying Upper-Limb Amputee Prosthesis Use to Inform Device Design

DTIC Science & Technology

2016-10-01

study of the resulting videos led to a new prosthetics-use taxonomy that is generalizable to various levels of amputation and terminal devices. The...taxonomy was applied to classification of the recorded videos via custom tagging software with midi controller interface. The software creates...a motion capture studio and video cameras to record accurate and detailed upper body motion during a series of standardized tasks. These tasks are

Prosthetic Smart Socket Technology to Improve Patient Interaction, Usability, Comfort, Fit and Function

DTIC Science & Technology

2017-10-01

AWARD NUMBER: W81XWH-16-1-0785 TITLE: Prosthetic Smart Socket Technology to Improve Patient Interaction, Usability, Comfort, Fit and Function...2016 - 29 Sep 2017 4. TITLE AND SUBTITLE Prosthetic Smart Socket Technology to Improve Patient Interaction, Usability, Comfort, Fit and Function 5a...discomfort. 2. KEYWORDS: Provide a brief list of keywords (limit to 20 words). Prosthesis, prosthesis fit, technology , skin problems, amputee

Sustainment and Advancement of Amputee Care

DTIC Science & Technology

2015-04-08

fitted with an IDEO TM , the RTR clinical pathway takes 12 weeks to complete. 169 The IDEO TM is a “ custom carbon fiber energy storage and...advances in three-dimensional printing may allow for individualized patient and function-specific customization , as well as rapid manufacturing of...Jay attended college for a year; worked construction for 3 years; worked in a restaurant in Chicago for a year before joining the Navy in 2006

A training programme to improve hip strength in persons with lower limb amputation.

PubMed

Nolan, Lee

2012-03-01

To investigate the effect of a 10-week training programme on persons with a lower limb amputation and to determine if this training is sufficient to enable running. Seven transtibial, 8 transfemoral and 1 bilateral amputee (all resulting from trauma, tumour or congenital) were randomly assigned to a training (n  =8) or control group (n = 8). Isokinetic hip flexor and extensor strength at 60 and 120º/s and oxygen consumption while walking at 1.0 m/s were tested pre- and post- a 10-week period. The training group followed a twice weekly hip strengthening programme, while the control group continued with their usual activities. Running ability was determined pre-testing, and attempted after post-testing for the training group only. The training group increased hip strength and decreased oxygen consumption. Six amputees who were previously unable to run were able to after training. The control group decreased intact limb hip extensor strength. The training programme is sufficient to improve hip strength and enable running in persons with a lower limb amputation. As hip strength was reduced in those not following the training programme, it is recommended that strength training be undertaken regularly in order to avoid losing limb strength following amputation.

Characterisation of dynamic couplings at lower limb residuum/socket interface using 3D motion capture.

PubMed

Tang, Jinghua; McGrath, Michael; Laszczak, Piotr; Jiang, Liudi; Bader, Dan L; Moser, David; Zahedi, Saeed

2015-12-01

Design and fitting of artificial limbs to lower limb amputees are largely based on the subjective judgement of the prosthetist. Understanding the science of three-dimensional (3D) dynamic coupling at the residuum/socket interface could potentially aid the design and fitting of the socket. A new method has been developed to characterise the 3D dynamic coupling at the residuum/socket interface using 3D motion capture based on a single case study of a trans-femoral amputee. The new model incorporated a Virtual Residuum Segment (VRS) and a Socket Segment (SS) which combined to form the residuum/socket interface. Angular and axial couplings between the two segments were subsequently determined. Results indicated a non-rigid angular coupling in excess of 10° in the quasi-sagittal plane and an axial coupling of between 21 and 35 mm. The corresponding angular couplings of less than 4° and 2° were estimated in the quasi-coronal and quasi-transverse plane, respectively. We propose that the combined experimental and analytical approach adopted in this case study could aid the iterative socket fitting process and could potentially lead to a new socket design. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

Socket Interface Pressure and Amputee Reported Outcomes for Comfortable and Uncomfortable Conditions of Patellar Tendon Bearing Socket: A Pilot Study.

PubMed

Safari, Mohammad Reza; Tafti, Nahid; Aminian, Gholamreza

2015-01-01

The objectives of the current study were to compare intra-socket pressure differences between comfortable and uncomfortable socket conditions, and the usefulness of subject perception of satisfaction, activity limitations, and socket comfort in distinguishing between these two socket conditions. Five unilateral trans-tibial amputees took part in the study. They answered the Socket Comfort Score (SCS) and Trinity Amputation and Prosthetic Experience Scale (TAPES) questionnaires before the interface pressure (in standing and walking) was measured for the uncomfortable socket condition at five regions of the residual limb. Participants were then provided with a comfortable socket and wore it for two weeks. Participants who were satisfied with the socket fit after two weeks repeated the SCS and TAPES questionnaires and interface pressure measurements. The differences between the test results of the two conditions were not statistically significant, except for the interface pressure at the popliteal region during the early stance phase, TAPES socket fit subscale, and the SCS. Due to large variability of the data and the lack of statistical significance, no firm conclusion can be made on the possible relationship between the interface pressure values and the patient-reported outcomes of the two socket conditions. A larger sample size and longer acclimation period are required to locate significant differences.

The experiences of people with diabetes-related lower limb amputation at the Komfo Anokye Teaching Hospital (KATH) in Ghana.

PubMed

Amoah, Vida Maame Kissiwaa; Anokye, Reindolf; Acheampong, Enoch; Dadson, Helina Rubby; Osei, Mary; Nadutey, Alberta

2018-01-24

Lower limb amputation not only causes major disfigurement, but renders people less mobile and at risk of loss of independence. Yet with appropriate rehabilitation, many people can learn to walk or function again and live high quality lives. This study sought to explore the experiences of patients with diabetes-related lower limb amputation at the Komfo Anokye Teaching Hospital. An exploratory study design was adopted using a qualitative approach and a purposive sampling to select 10 participants for the study. A semi-structured interview guide was used with an in-depth face-to-face interview. The interview was tape-recorded with an audio recorder while notes were taken in addition to the audio recording. There were varying degrees of experiences ranging from physical as well as psychological and economic challenges. Amputees had to cope with playing entirely new roles after the amputation. They also experienced some economic challenges which were as a result of their inability to work. Some of the amputees consoled themselves with the fact that, despite their condition, they were better than other people. Others believed that whatever happened was Gods doing and nothing could be done about it. This self-consolation and the belief in God helped them to cope.

Kinematic and biomimetic assessment of a hydraulic ankle/foot in level ground and camber walking

PubMed Central

Bai, Xuefei; Ewins, David; Crocombe, Andrew D.

2017-01-01

Improved walking comfort has been linked with better bio-mimicking of the prosthetic ankle. This study investigated if a hydraulic ankle/foot can provide enough motion in both the sagittal and frontal planes during level and camber walking and if the hydraulic ankle/foot better mimics the biological ankle moment pattern compared with a fixed ankle/foot device. Five active male unilateral trans-femoral amputees performed level ground walking at normal and fast speeds and 2.5° camber walking in both directions using their own prostheses fitted with an “Echelon” hydraulic ankle/foot and an “Esprit” fixed ankle/foot. Ankle angles and the Trend Symmetry Index of the ankle moments were compared between prostheses and walking conditions. Significant differences between prostheses were found in the stance plantarflexion and dorsiflexion peaks with a greater range of motion being reached with the Echelon foot. The Echelon foot also showed significantly improved bio-mimicry of the ankle resistance moment in all walking conditions, either compared with the intact side of the same subject or with the “normal” mean curve from non-amputees. During camber walking, both types of ankle/foot devices showed similar changes in the frontal plane ankle angles. Results from a questionnaire showed the subjects were more satisfied with Echelon foot. PMID:28704428

Prosthesis rejection in acquired major upper-limb amputees: a population-based survey.

PubMed

Østlie, Kristin; Lesjø, Ingrid Marie; Franklin, Rosemary Joy; Garfelt, Beate; Skjeldal, Ola Hunsbeth; Magnus, Per

2012-07-01

To estimate the rates of primary and secondary prosthesis rejection in acquired major upper-limb amputees (ULAs), to describe the most frequently reported reasons for rejection and to estimate the influence of background factors on the risk of rejection. Cross-sectional study analysing population-based questionnaire data (n = 224). Effects were analysed by logistic regression analyses and Cox regression analyses. Primary prosthesis rejection was found in 4.5% whereas 13.4% had discontinued prosthesis use. The main reasons reported for primary non-wear were a perceived lack of need and discrepancies between perceived need and the prostheses available. The main reasons reported for secondary prosthesis rejection were dissatisfaction with prosthetic comfort, function and control. Primary prosthesis rejection was more likely in ULAs amputated at high age and in ULAs with proximal amputations. Secondary prosthesis rejection was more likely in proximal ULAs and in women. Clinicians should be aware of the increased risk of rejection in proximal ULAs, elderly ULAs and in women. Emphasising individual needs will probably facilitate successful prosthetic fitting. Improved prosthesis quality and individualised prosthetic training may increase long-term prosthesis use. Further studies of the effect of prosthetic training and of the reasons for rejection of different prosthetic types are suggested.

A quasi-dynamic nonlinear finite element model to investigate prosthetic interface stresses during walking for trans-tibial amputees.

PubMed

Jia, Xiaohong; Zhang, Ming; Li, Xiaobing; Lee, Winson C C

2005-07-01

To predict the interface pressure between residual limb and prosthetic socket for trans-tibial amputees during walking. A quasi-dynamic finite element model was built based on the actual geometry of residual limb, internal bones and socket liner. To simulate the friction/slip boundary conditions between the skin and liner, automated surface-to-surface contact was used. Besides variable external loads and material inertia, the coupling between the large rigid displacement of knee joint and small elastic deformation of residual limb and prosthetic components were also considered. Interface pressure distribution was found to have the same profile during walking. The high pressures fall over popliteal depression, middle patella tendon, lateral tibia and medial tibia regions. Interface pressure predicted by static or quasi-dynamic analysis had the similar double-peaked waveform shape in stance phase. The consideration of inertial effects and motion of knee joint cause 210% average variation of the area between the pressure curve and the horizontal line of pressure threshold between two cases, even though there is only a small change in the peak pressure. The findings in this paper show that the coupling dynamic effects of inertial loads and knee flexion must be considered to study interface pressure between residual limb and prosthetic socket during walking.

Kinematic and biomimetic assessment of a hydraulic ankle/foot in level ground and camber walking.

PubMed

Bai, Xuefei; Ewins, David; Crocombe, Andrew D; Xu, Wei

2017-01-01

Improved walking comfort has been linked with better bio-mimicking of the prosthetic ankle. This study investigated if a hydraulic ankle/foot can provide enough motion in both the sagittal and frontal planes during level and camber walking and if the hydraulic ankle/foot better mimics the biological ankle moment pattern compared with a fixed ankle/foot device. Five active male unilateral trans-femoral amputees performed level ground walking at normal and fast speeds and 2.5° camber walking in both directions using their own prostheses fitted with an "Echelon" hydraulic ankle/foot and an "Esprit" fixed ankle/foot. Ankle angles and the Trend Symmetry Index of the ankle moments were compared between prostheses and walking conditions. Significant differences between prostheses were found in the stance plantarflexion and dorsiflexion peaks with a greater range of motion being reached with the Echelon foot. The Echelon foot also showed significantly improved bio-mimicry of the ankle resistance moment in all walking conditions, either compared with the intact side of the same subject or with the "normal" mean curve from non-amputees. During camber walking, both types of ankle/foot devices showed similar changes in the frontal plane ankle angles. Results from a questionnaire showed the subjects were more satisfied with Echelon foot.

BIOENERGETIC DIFFERENCES DURING WALKING AND RUNNING IN TRANSFEMORAL AMPUTEE RUNNERS USING ARTICULATING AND NON-ARTICULATING KNEE PROSTHESES

PubMed Central

Highsmith, M. Jason; Kahle, Jason T.; Miro, Rebecca M.; Mengelkoch, Larry J.

2016-01-01

Transfemoral amputation (TFA) patients require considerably more energy to walk and run than non-amputees. The purpose of this study was to examine potential bioenergetic differences (oxygen uptake (VO2), heart rate (HR), and ratings of perceived exertion (RPE)) for TFA patients utilizing a conventional running prosthesis with an articulating knee mechanism versus a running prosthesis with a non-articulating knee joint. Four trained TFA runners (n = 4) were accommodated to and tested with both conditions. VO2 and HR were significantly lower (p ≤ 0.05) in five of eight fixed walking and running speeds for the prosthesis with an articulating knee mechanism. TFA demonstrated a trend for lower RPE at six of eight walking speeds using the prosthesis with the articulated knee condition. A trend was observed for self-selected walking speed, self-selected running speed, and maximal speed to be faster for TFA subjects using the prosthesis with the articulated knee condition. Finally, all four TFA participants subjectively preferred running with the prosthesis with the articulated knee condition. These findings suggest that, for trained TFA runners, a running prosthesis with an articulating knee prosthesis reduces ambulatory energy costs and enhances subjective perceptive measures compared to using a non-articulating knee prosthesis. PMID:28066524

Phantom Radiculopathy: Case Report and Review of the Literature.

PubMed

Croci, Davide; Fandino, Javier; Marbacher, Serge

2016-06-01

Phantom radicular pain is very uncommon. To the best of our knowledge, only 14 cases have been described in the literature. A review of the literature revealed the most common cause of phantom radicular pain to be lumbar disc herniation and, furthermore, that treatment with epidural steroid injection or surgical decompression relieves pain in almost all cases. A significant number of patients with superimposed phantom radiculopathy may be missed because of the high incidence of degenerative lumbar spine diseases in the adult population, as well as the fact that amputee patients very often present with mixed stump and phantom pain. We report a case of a patient presenting with new-onset phantom radicular pain (S1 left) 4 years after an above-the-knee amputation (left). Computed tomography myelography showed compression of the left S1 nerve root caused by recurrent disc herniation and scar tissue formation after previous discectomy at L5-S1. The patient experienced temporarily relief of the sciatic pain after a fluoroscopically-guided epidural transforaminal steroid injection. Subsequent microsurgical decompression led to complete remission of the phantom radicular pain. Amputees experiencing recurrent phantom radicular pain or new-onset superimposed pain deserve further radiologic evaluation. Copyright © 2016 Elsevier Inc. All rights reserved.

Hands-Off and Hands-On Casting Consistency of Amputee below Knee Sockets Using Magnetic Resonance Imaging

PubMed Central

Rowe, Philip

2013-01-01

Residual limb shape capturing (Casting) consistency has a great influence on the quality of socket fit. Magnetic Resonance Imaging was used to establish a reliable reference grid for intercast and intracast shape and volume consistency of two common casting methods, Hands-off and Hands-on. Residual limbs were cast for twelve people with a unilateral below knee amputation and scanned twice for each casting concept. Subsequently, all four volume images of each amputee were semiautomatically segmented and registered to a common coordinate system using the tibia and then the shape and volume differences were calculated. The results show that both casting methods have intra cast volume consistency and there is no significant volume difference between the two methods. Inter- and intracast mean volume differences were not clinically significant based on the volume of one sock criteria. Neither the Hands-off nor the Hands-on method resulted in a consistent residual limb shape as the coefficient of variation of shape differences was high. The resultant shape of the residual limb in the Hands-off casting was variable but the differences were not clinically significant. For the Hands-on casting, shape differences were equal to the maximum acceptable limit for a poor socket fit. PMID:24348164

Clinical field follow-up of high density polyethylene (HDPE)-Jaipur prosthetic technology for trans-tibial amputees.

PubMed

Jensen, J S; Craig, J G; Mtalo, L B; Zelaya, C M

2004-12-01

The purpose of this study was to examine the outcome of the application of the High Density Polyethylene (HDPE)-Jaipur prosthetic construction in fitting trans-tibial amputees in a number of projects in the developing world. Projects in Honduras, Uganda and India were visited. Three hundred and twenty (320) patients had been provided with a HDPE-Jaipur prosthesis and of these 172 were seen for a technical and clinical follow-up after a median of 35 months. More than half the amputations were due to trauma, the remainder to disease. Fabrication and fitting in the three projects was carried out by individuals who had undertaken a twice week training course provided by Bhagwan Mahaveer Viklang Sahayata Samiti limb centre in Jaipur. The individuals involved had limited background training in prosthetics. Craftsmanship and fit were assessed as being poor in 56% of cases. The technical quality of the Jaipur foot was considered acceptable as its performance was better than previously observed results. Although there was patient satisfaction of 85% and compliance of 94% the HDPE-Jaipur trans-tibial system was not considered acceptable as 49% reported walking distances less than 1km and 36% discomfort. The major inadequacy in outcome relates to the use for fabrication and fitting of individuals with inadequate education and training.

Return to duty and disability after combat-related hindfoot injury.

PubMed

Sheean, Andrew J; Krueger, Chad A; Hsu, Joseph R

2014-11-01

To characterize the return-to-duty (RTD) rates and disability outcomes for soldiers who sustained combat-related hindfoot injuries that were treated with either reconstruction or transtibial amputation (TTA). Retrospective cohort series. Tertiary trauma center. All patients treated for combat-related hindfoot injuries between May 2005 and July 2011. TTA or hindfoot reconstruction/ankle fusion. Age, RTD rate, combined disability, and associated disabling conditions. One hundred twenty-two patients underwent treatment for combat-related hindfoot injuries. Fifty-seven patients were treated with amputation, and 65 patients were treated with hindfoot reconstruction or ankle fusion. The overall RTD rate was 20%. Amputees had a RTD rate of 12%, which was lower than those who had a fusion or hindfoot repair [26% (P < 0.06)]. The disability ratings of amputees were significantly higher than those patients undergoing either ankle fusion or primary hindfoot repair [75% and 62%, respectively (P < 0.006)]. While RTD rates were higher for hindfoot reconstruction or ankle fusion compared with TTA, psychiatric conditions were more common among these patients. Although there were clear differences between both groups, the relationship between true functional outcomes and disability ratings remains unclear and both treatment groups seem to do poorly in terms of returning to active duty. Therapeutic level III. See instructions for authors for a complete description of levels of evidence.

Biomechanics principle of elbow joint for transhumeral prostheses: comparison of normal hand, body-powered, myoelectric & air splint prostheses.

PubMed

Abd Razak, Nasrul Anuar; Abu Osman, Noor Azuan; Gholizadeh, Hossein; Ali, Sadeeq

2014-09-10

Understanding of kinematics force applied at the elbow is important in many fields, including biomechanics, biomedical engineering and rehabilitation. This paper provides a comparison of a mathematical model of elbow joint using three different types of prosthetics for transhumeral user, and characterizes the forces required to overcome the passive mechanical of the prosthetics at the residual limb. The study modeled the elbow as a universal joint with intersecting axes of x-axis and y-axis in a plain of upper arm and lower arm. The equations of force applied, torque, weight and length of different type of prosthetics and the anthropometry of prosthetics hand are discussed in this study. The study also compares the force, torque and pressure while using all three types of prosthetics with the normal hand. The result was measured from the elbow kinematics of seven amputees, using three different types of prosthetics. The F-Scan sensor used in the study is to determine the pressure applied at the residual limb while wearing different type of prostheses. These technological advances in assessment the biomechanics of an elbow joint for three different type of prosthetics with the normal hand bring the new information for the amputees and prosthetist to choose the most suitable device to be worn daily.

Sport prostheses and prosthetic adaptations for the upper and lower limb amputees: an overview of peer reviewed literature.

PubMed

Bragaru, Mihai; Dekker, Rienk; Geertzen, Jan H B

2012-09-01

Sport prostheses are used by both upper- and lower-limb amputees while participating in sports and other physical activities. Although the number of these devices has increased over the past decade, no overview of the peer reviewed literature describing them has been published previously. Such an overview will allow specialists to choose appropriate prostheses based on available scientific evidence rather than on personal experience or preference. To provide an overview of the sport prostheses as they are described by the papers published in peer reviewed literature. Literature review. Four electronic databases were searched using free text and Medical Subject Headings (MESH) terms. Papers were included if they concerned a prosthesis or a prosthetic adaptation used in sports. Papers were excluded if they did not originate from peer reviewed sources, if they concerned prostheses for body parts other than the upper or lower limbs, if they concerned amputations distal to the wrist or ankle, or if they were written in a language other than English. Twenty-four papers were included in this study. The vast majority contained descriptive data and consisted of expert opinions and technical notes. Data concerning the energy efficiency, technical characteristics and special mechanical properties of prostheses or prosthetic adaptations for sports, other than running, are scarce.

Spatial asymmetry in tactile sensor skin deformation aids perception of edge orientation during haptic exploration.

PubMed

Ponce Wong, Ruben D; Hellman, Randall B; Santos, Veronica J

2014-01-01

Upper-limb amputees rely primarily on visual feedback when using their prostheses to interact with others or objects in their environment. A constant reliance upon visual feedback can be mentally exhausting and does not suffice for many activities when line-of-sight is unavailable. Upper-limb amputees could greatly benefit from the ability to perceive edges, one of the most salient features of 3D shape, through touch alone. We present an approach for estimating edge orientation with respect to an artificial fingertip through haptic exploration using a multimodal tactile sensor on a robot hand. Key parameters from the tactile signals for each of four exploratory procedures were used as inputs to a support vector regression model. Edge orientation angles ranging from -90 to 90 degrees were estimated with an 85-input model having an R (2) of 0.99 and RMS error of 5.08 degrees. Electrode impedance signals provided the most useful inputs by encoding spatially asymmetric skin deformation across the entire fingertip. Interestingly, sensor regions that were not in direct contact with the stimulus provided particularly useful information. Methods described here could pave the way for semi-autonomous capabilities in prosthetic or robotic hands during haptic exploration, especially when visual feedback is unavailable.

Hands-off and hands-on casting consistency of amputee below knee sockets using magnetic resonance imaging.

PubMed

Safari, Mohammad Reza; Rowe, Philip; McFadyen, Angus; Buis, Arjan

2013-01-01

Residual limb shape capturing (Casting) consistency has a great influence on the quality of socket fit. Magnetic Resonance Imaging was used to establish a reliable reference grid for intercast and intracast shape and volume consistency of two common casting methods, Hands-off and Hands-on. Residual limbs were cast for twelve people with a unilateral below knee amputation and scanned twice for each casting concept. Subsequently, all four volume images of each amputee were semiautomatically segmented and registered to a common coordinate system using the tibia and then the shape and volume differences were calculated. The results show that both casting methods have intra cast volume consistency and there is no significant volume difference between the two methods. Inter- and intracast mean volume differences were not clinically significant based on the volume of one sock criteria. Neither the Hands-off nor the Hands-on method resulted in a consistent residual limb shape as the coefficient of variation of shape differences was high. The resultant shape of the residual limb in the Hands-off casting was variable but the differences were not clinically significant. For the Hands-on casting, shape differences were equal to the maximum acceptable limit for a poor socket fit.

Neuromimetic Event-Based Detection for Closed-Loop Tactile Feedback Control of Upper Limb Prostheses

PubMed Central

Osborn, Luke; Kaliki, Rahul; Soares, Alcimar; Thakor, Nitish

2016-01-01

Upper limb amputees lack the valuable tactile sensing that helps provide context about the surrounding environment. Here we utilize tactile information to provide active touch feedback to a prosthetic hand. First, we developed fingertip tactile sensors for producing biomimetic spiking responses for monitoring contact, release, and slip of an object grasped by a prosthetic hand. We convert the sensor output into pulses, mimicking the rapid and slowly adapting spiking responses of receptor afferents found in the human body. Second, we designed and implemented two neuromimetic event-based algorithms, Compliant Grasping and Slip Prevention, on a prosthesis to create a local closed-loop tactile feedback control system (i.e. tactile information is sent to the prosthesis). Grasping experiments were designed to assess the benefit of this biologically inspired neuromimetic tactile feedback to a prosthesis. Results from able-bodied and amputee subjects show the average number of objects that broke or slipped during grasping decreased by over 50% and the average time to complete a grasping task decreased by at least 10% for most trials when comparing neuromimetic tactile feedback with no feedback on a prosthesis. Our neuromimetic method of closed-loop tactile sensing is a novel approach to improving the function of upper limb prostheses. PMID:27777640

Polyurethane gel liner usage in the Oxford Prosthetic Service.

PubMed

Hatfield, A G; Morrison, J D

2001-04-01

The objective was to investigate which lower limb amputees are using Alpha polyurethane gel liners and the effects of these on comfort and suspension of their prosthesis. A retrospective study was carried out of case records of all patients issued with Alpha cushion and locking liners between 1997 and the end of January 1999. The type of liner used was compared with age, sex, level and cause of amputation, time since amputation, comfort and suspension. Modified Stanmore/Harold-Wood mobility grades; duration of use and number of liners issued per patient were recorded. Sixteen (16) patients were identified who had been prescribed Alpha cushion liners. Improved comfort was reported by all. Forty (40) patients were identified who had been prescribed Alpha locking liners. Twenty (20) of these reported improved comfort and 10 improved suspension. The average time since amputation was 18.5 years for those using cushion liners and 14.1 years for locking liner users. Fifty-two (52) of all 56 patients using Alpha cushion and locking liners had mobility grades of 4 or more. Trauma was the most common cause of amputation. This group is a relatively mobile group of amputees. All those using cushion liners reported improved comfort. Some of the locking liner users reported improved comfort and suspension but this was not universally the case.

The relationship between trans-femoral prosthesis alignment and the center trajectory of plantar pressure in the frontal plane

PubMed Central

Nomura, Tomohiro; Watanabe, Kota; Nosaka, Toshiya; Matsubara, Hiroyuki; Akiyama, Masaharu; Inui, Kimiharu

2016-01-01

[Purpose] It is difficult to identify by visual observation whether alignment abnormalities in trans-femoral prostheses in the frontal plane are attributable to the adduction angle or the abnormal alignment of the positions of the medial and lateral sides of the socket in relation to the foot. Therefore, we focused on the trajectory of the center of plantar pressure during walking, and we proposed a method for differentiating these two alignment abnormalities. [Subjects and Methods] We recruited 4 trans-femoral unilateral amputees. Bench alignment was achieved initially. We compared the amplitude of the trajectory of the center of plantar pressure when walking under 2 conditions: 1) when changing the adduction angle and 2) when changing the positional relationship between the socket and the foot. [Results] It was not possible to distinguish between the 2 types of malalignment on the prosthesis side. There was a significant difference when changing the positional relationship on the contralateral side. Thereby, the plantar pressure of the contralateral side could be used to distinguish between the 2 types of malalignment. [Conclusion] The results of this study suggested that trans-femoral prosthesis malalignment could be evaluated through the plantar pressure of the contralateral side in amputees. PMID:27065546

The incidence of pelvic fractures with traumatic lower limb amputation in modern warfare due to improvised explosive devices.

PubMed

Cross, A M; Davis, C; Penn-Barwell, J; Taylor, D M; De Mello, W F; Matthews, J J

2014-01-01

A frequently-seen injury pattern in current military experience is traumatic lower limb amputation as a result of improvised explosive devices (IEDs). This injury can coexist with fractures involving the pelvic ring. This study aims to assess the frequency of concomitant pelvic fracture in IED-related lower limb amputation. A retrospective analysis of the trauma charts, medical notes, and digital imaging was undertaken for all patients arriving at the Emergency Department at the UK military field hospital in Camp Bastion, Afghanistan, with a traumatic lower limb amputation in the six months between September 2009 and April 2010, in order to determine the incidence of associated pelvic ring fractures. Of 77 consecutive patients with traumatic lower limb amputations, 17 (22%) had an associated pelvic fracture (eleven with displaced pelvic ring fractures, five undisplaced fractures and one acetabular fracture). Unilateral amputees (n = 31) had a 10% incidence of associated pelvic fracture, whilst 30 % of bilateral amputees (n = 46) had a concurrent pelvic fracture. However, in bilateral, trans-femoral amputations (n = 28) the incidence of pelvic fracture was 39%. The study demonstrates a high incidence of pelvic fractures in patients with traumatic lower limb amputations, supporting the routine pre-hospital application of pelvic binders in this patient group.

The Effect of a Microprocessor Prosthetic Foot on Function and Quality of Life in Transtibial Amputees Who Are Limited Community Ambulators

DTIC Science & Technology

2017-09-01

parallel, randomized, controlled clinical trial designed to determine if a microprocessor controlled prosthetic foot (MPF), with greater range of...clinical trial designed to determine if a microprocessor controlled prosthetic foot (MPF), with greater range of motion and active power, will...Department of the Army position, policy or decision unless so designated by other documentation. CONTRACTING ORGANIZATION: University of Tennessee

Benefit from NASA

NASA Image and Video Library

2004-04-15

In this photograph, Amputee Amie Bradly uses a NASA-developed prosthesis to paint her fingernails. Derived from foam insulation technology used to protect the Space Shuttle External Tank from excessive heat, FAB/CAD, a subsidiary of the Harshberger Prosthetic and Orthotic Center, utilized the technology to replace the heavy, fragile plaster they used to produce master molds for prosthetics. The new material was lighter, cheaper and easier to manufacture than plaster, resulting in lower costs to the customer.

[The esthetics of lower limb prosthesis].

PubMed

Gardrat, Franck

2015-01-01

The amputation, which is upper or lower limb, entails important consequences and often traumatic into subject amputee from a physical, psychological, interpersonal and social point of view. It acts on the body image unleashing different psychological disorders and alterations in the social and professional reality. The aesthetic prosthesis can be considered a good support to help the person regain a new body image of themselves, facilitating the process of physical rehabilitation and social integration.

Prosthesis Material

NASA Technical Reports Server (NTRS)

2004-01-01

In this photograph, Amputee Amie Bradly uses a NASA-developed prosthesis to paint her fingernails. Derived from foam insulation technology used to protect the Space Shuttle External Tank from excessive heat, FAB/CAD, a subsidiary of the Harshberger Prosthetic and Orthotic Center, utilized the technology to replace the heavy, fragile plaster they used to produce master molds for prosthetics. The new material was lighter, cheaper and easier to manufacture than plaster, resulting in lower costs to the customer.

Mobile Gait Analysis System for Lower Limb Amputee High-Level Activity Rehabilitation

DTIC Science & Technology

2013-09-01

The direction of gravity can be used, along with trigonometry, to determine the pitch and roll orientations of the IMU . We are interested in the...are represented using direction cosine matrices so pitch and roll rotations can be isolated while rotations about the gravity vector are ignored...three signals from the gyroscope in the IMU frame and any drift associated with the gyroscope, and . An estimate of roll and pitch, and

Improved Training Method for Rapid Rehabilitation of Amputees

DTIC Science & Technology

2014-03-01

return to active duty or to a productive civilian life. Body This was the third year of a research effort to develop and test a novel training...a velocity standardized to leg length. This test assessment of the rehabilitative program is performed before and after the two week training on the...control group : Comparisons were also made between patients who had not been enrolled in the research study to patients who had participated in the

Mobile Gait Analysis System for Lower Limb Amputee High-Level Activity Rehabilitation

DTIC Science & Technology

2012-09-01

take this data and give the clinician information they can use immediately to get more insight into existing prosthesis fit or alignment issues, help...Modification of Smart Pylon for prosthesis fit, alignment and gait training purposes – 20 In May the larger, more rugged trans-tibial (TT) Smart Pylon...data to determine metrics to indicate positive patient biomechanics factors and indicate successful prosthesis fit and alignment This will be

Measurement of Forces and Moments Transmitted to the Residual Limb

DTIC Science & Technology

2010-10-01

forces, moments, and alignments. 15. SUBJECT TERMS Amputees, prosthesis alignment, socket pressure, gait, force and moment sensors 16. SECURITY...evaluate the feasibility of using a tri-axial transducer mounted to the pylon of a lower limb prosthesis directly below the socket to a.) Characterize...weighing up to nearly 500lbs, or activities which involve deceleration or acceleration forces of up to 500 lbs along the pylon of a prosthesis . Diameter

Measurement of Forces and Moments Transmitted to the Residual Limb

DTIC Science & Technology

2008-08-01

leg and residual limb, the condition of your residual limb including touch and pressure sensation, and the type of components used in your prosthesis ...measured by a tri-axial transducer mounted on the pylon of a transtibial prosthesis distal to the socket can be used to estimate the intra-socket...alignment has been developed, and IRB approval has been obtained. 15. SUBJECT TERMS Amputees, prosthesis alignment, socket pressure, gait, force and moment

Bar-holding prosthetic limb

NASA Technical Reports Server (NTRS)

Vest, Thomas W. (Inventor); Norton, William E. (Inventor); Belcher, Jewell G. (Inventor); Carden, James R. (Inventor)

1992-01-01

A prosthetic device for below-the-elbow amputees is disclosed. The device has a removable effector, which is attached to the end of an arm cuff. The effector is comprised of a pair of C-shaped members that are oriented so as to face each other. Working in concert, the C-shaped members are able to hold a bar such as a chainsaw handle. A flat spring is fitted around the C-shaped members to hold them together.

Uniformed Services University of the Health Sciences Journal, 2001 Edition

DTIC Science & Technology

2002-05-15

rehabilitation system developed by Movement and Sports Specialists, Inc., which improves physical rehabilitation of mine amputees through the use of new...unique challenges created by the use of biologic, chemical and radiologic weapons, we were especially pleased to note that DoD’s University of the...improving the quality of life for our service members, retirees, and families. All of us in the Office of the Secretary of Defense place great emphasis

Comparison of different microprocessor controlled knee joints on the energy consumption during walking in trans-femoral amputees: intelligent knee prosthesis (IP) versus C-leg.

PubMed

Chin, Takaaki; Machida, Katsuhiro; Sawamura, Seishi; Shiba, Ryouichi; Oyabu, Hiroko; Nagakura, Yuji; Takase, Izumi; Nakagawa, Akio

2006-04-01

The purpose of this study was to investigate the characteristic differences between the IP and C-Leg by making a comparative study of energy consumption and walking speeds in trans-femoral amputees. The subjects consisted of four persons with traumatic trans-femoral amputations aged 17 - 33 years who had been using the IP and were active in society. Fourteen able-bodied persons served as controls. First the energy consumption at walking speeds of 30, 50, 70, and 90 m/min was measured when using the IP. Then the knee joint was switched to the C-Leg. The same energy consumption measurement was taken once the subjects were accustomed to using the C-Leg. The most metabolically efficient walking speed was also determined. At a walking speed of 30 m/min using the IP and C-Leg, the oxygen rate (ml/kg/ min) was, on average, 42.5% and 33.3% higher (P< 0.05) than for the able-bodied group. At 50 m/min, the equivalent figures were 56.6% and 49.5% (P< 0.05), while at 70 m/min the figures were 57.8% and 51.2% (P<0.05), and at 90m/min the figures were 61.9% and 55.2% (P<0.05%). Comparing the oxygen rates for the subjects using the IP and C-Leg at walking speeds of 30 m/min and 90 m/min it was found that subjects who used C-Leg walked somewhat more efficiently than those who used IP. However, there was no significant difference between the two types at each walking speed. It was also determined that the most energy-efficient walking speed for subjects using the IP and C-Leg was the same as for the controls. Although the subjects in this study walked with comparable speed and efficiency whether they used the IP or C-Leg, the subjects' energy consumption while walking with the IP and C-Leg at normal speeds were much lower than previously reported. This study suggested that the microprocessor controlled knee joints appeared to be valid alternative for improving walking performance of trans-femoral amputees.

The Effect of Prosthetic Socket Interface Design on Socket Comfort, Residual Limb Health, and Function for the Transfemoral Amputee

DTIC Science & Technology

2017-10-01

significantly lower trim lines, without ischial containment compared with a traditional interface. However, these alternative designs could compromise...overall function compared to the standard of care interface design . Therefore the focus of this clinical trial is to determine if the DS and Sub-I...alternative interface designs will improve socket comfort, residual limb health and function compared to the standard of care IRC interface design . 15

Fiscal Year 2011 United States Army Annual Financial Report. America’s Army: At a Strategic Crossroads

DTIC Science & Technology

2011-01-01

successful in any operational scenario. In FY 2011, the Army updated the Cost of the Doctrinal Army Model using improved and refined methods and the...8,100 severely wounded Soldiers and veterans with cases spanning from Post- Traumatic Stress Disorder to double amputees. This population is supported... method dubbed “EoIP” (Everything over Internet Protocol). Getting the right information at the right time requires universal accessibility

To direct the Secretary of Veterans Affairs to display in each facility of the Department of Veterans Affairs a Women Veterans Bill of Rights and to display in each prosthetics and orthotics clinic of the Department an Injured and Amputee Veterans Bill of Rights, and for other purposes.

THOMAS, 111th Congress

Rep. Filner, Bob [D-CA-51

2010-07-29

Senate - 12/01/2010 Received in the Senate and Read twice and referred to the Committee on Veterans' Affairs. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

The Effect of Prosthetic Socket Interface Design on Socket Comfort, Residual Limb Health, and Function for the Transfemoral Amputee

DTIC Science & Technology

2016-10-01

laminated rigid frame to reduce thermal layers, increase flexibility and comfort while retaining ischial containment. In contrast, a Sub-I design has...design is comprised of a flexible interface and minimal laminated rigid frame to reduce thermal layers, increase flexibility and comfort while...AWARD NUMBER: W81XWH-15-1-0410 TITLE: The Effect of Prosthetic Socket Interface Design on Socket Comfort , Residual Limb Health, and Function

Physical Performance Assessment in Military Service Members

DTIC Science & Technology

2012-08-01

funded by a grant from the Military Amputee Research Program. The views expressed in this article are those of the authors and do not reflect the official...Fort Sam Houston, Texas . Partici- pants ranged in age from 18 to 43 years and had no current or recent history (within 6 months) of medical or...in older adults (age >65 years).17 How- ever, limited research exists regarding normal TSA in younger adults. We define TSA as the ability to ascend

Determining Clinically Relevant Changes in Community Walking Metrics to Be Tracked by the VA as Part of Routine Care in Lower Limb Amputee Veterans

DTIC Science & Technology

2017-10-01

20007 REPORT DATE: October 2017 TYPE OF REPORT : Annual PREPARED FOR: U.S. Army Medical Research and Materiel Command Fort Detrick, Maryland...21702-5012 DISTRIBUTION STATEMENT: Approved for Public Release; Distribution Unlimited The views, opinions and/or findings contained in this report ...other documentation. REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is

Functional Performance Evaluation of the Northwestern University Flexible Subischial Vacuum (NU-FlexSIV) Socket for Persons with Transfemoral Amputation

DTIC Science & Technology

2016-10-01

satisfaction with device’’ (i.e. prosthesis) than the IC Socket. During year 1, we received all required IRB approvals, registered the clinical... satisfaction with device” (i.e. prosthesis) than the IC Socket. 2. KEYWORDS: Prosthetic Socket, Artificial Limbs, Prosthesis, Transfemoral Amputee, Gait...FlexSIV Socket will result in better quality of life and “ satisfaction with device” (i.e. prosthesis) than the IC socket. Accomplishments under

Control of a Robotic Hand Using a Tongue Control System-A Prosthesis Application.

PubMed

Johansen, Daniel; Cipriani, Christian; Popovic, Dejan B; Struijk, Lotte N S A

2016-07-01

The aim of this study was to investigate the feasibility of using an inductive tongue control system (ITCS) for controlling robotic/prosthetic hands and arms. This study presents a novel dual modal control scheme for multigrasp robotic hands combining standard electromyogram (EMG) with the ITCS. The performance of the ITCS control scheme was evaluated in a comparative study. Ten healthy subjects used both the ITCS control scheme and a conventional EMG control scheme to complete grasping exercises with the IH1 Azzurra robotic hand implementing five grasps. Time to activate a desired function or grasp was used as the performance metric. Statistically significant differences were found when comparing the performance of the two control schemes. On average, the ITCS control scheme was 1.15 s faster than the EMG control scheme, corresponding to a 35.4% reduction in the activation time. The largest difference was for grasp 5 with a mean AT reduction of 45.3% (2.38 s). The findings indicate that using the ITCS control scheme could allow for faster activation of specific grasps or functions compared with a conventional EMG control scheme. For transhumeral and especially bilateral amputees, the ITCS control scheme could have a significant impact on the prosthesis control. In addition, the ITCS would provide bilateral amputees with the additional advantage of environmental and computer control for which the ITCS was originally developed.

Cortical motor activity and reorganization following upper-limb amputation and subsequent targeted reinnervation.

PubMed

Chen, Albert; Yao, Jun; Kuiken, Todd; Dewald, Julius P A

2013-01-01

Previous studies have postulated that the amount of brain reorganization following peripheral injuries may be correlated with negative symptoms or consequences. However, it is unknown whether restoring effective limb function may then be associated with further changes in the expression of this reorganization. Recently, targeted reinnervation (TR), a surgical technique that restores a direct neural connection from amputated sensorimotor nerves to new peripheral targets such as muscle, has been successfully applied to upper-limb amputees. It has been shown to be effective in restoring both peripheral motor and sensory functions via the reinnervated nerves as soon as a few months after the surgery. However, it was unclear whether TR could also restore normal cortical motor representations for control of the missing limb. To answer this question, we used high-density electroencephalography (EEG) to localize cortical activity related to cued motor tasks generated by the intact and missing limb. Using a case study of 3 upper-limb amputees, 2 of whom went through pre and post-TR experiments, we present unique quantitative evidence for the re-mapping of motor representations for the missing limb closer to their original locations following TR. This provides evidence that an effective restoration of peripheral function from TR can be linked to the return of more normal cortical expression for the missing limb. Therefore, cortical mapping may be used as a potential guide for monitoring rehabilitation following peripheral injuries.

Comparison of Rectified and Unrectified Sockets for Transtibial Amputees.

PubMed

Engsberg, Jack R; Sprouse, S Wayne; Uhrich, Mary L; Ziegler, Barbara R; Luitjohan, F Daniel

2008-01-01

The current method for fabricating prosthetic sockets is to modify a positive mold to account for the non-homogeneity of the residual limb to tolerate load (i.e., rectified socket). We tested unrectified sockets by retaining the shape of the residual limb, except for a distal end pad, using an alginate gel process instead of casting. This investigation compared rectified and unrectified sockets. Forty-three adults with unilateral transtibial amputations were tested after randomly wearing both rectified and unrectified sockets for at least 4 weeks. Testing included a gait analysis, energy expenditure and Prosthesis Evaluation Questionnaire (PEQ). Results indicated no differences between sockets for gait speed and timing, gait kinematics and kinetics, and gait energy expenditure. There were also no differences in the Prosthetic Evaluation Questionnaire and 16 subjects selected the rectified socket, 25 selected the unrectified socket, and 2 subjects selected to use both sockets as their exit socket. Results seemed to indicate that more than one paradigm exists for shaping prosthetic sockets, and this paradigm may be helpful in understanding the mechanisms of socket fit. The alginate gel fabrication method was simpler than the traditional method. The method could be helpful in other countries where prosthetic care is lacking, may be helpful with new amputees, and may be helpful in typical clinics to reduce costs and free the prosthetist to focus more time on patient needs.

Comparison of Rectified and Unrectified Sockets for Transtibial Amputees

PubMed Central

Engsberg, Jack R.; Sprouse, S. Wayne; Uhrich, Mary L.; Ziegler, Barbara R.; Luitjohan, F. Daniel

2008-01-01

The current method for fabricating prosthetic sockets is to modify a positive mold to account for the non-homogeneity of the residual limb to tolerate load (i.e., rectified socket). We tested unrectified sockets by retaining the shape of the residual limb, except for a distal end pad, using an alginate gel process instead of casting. This investigation compared rectified and unrectified sockets. Forty-three adults with unilateral transtibial amputations were tested after randomly wearing both rectified and unrectified sockets for at least 4 weeks. Testing included a gait analysis, energy expenditure and Prosthesis Evaluation Questionnaire (PEQ). Results indicated no differences between sockets for gait speed and timing, gait kinematics and kinetics, and gait energy expenditure. There were also no differences in the Prosthetic Evaluation Questionnaire and 16 subjects selected the rectified socket, 25 selected the unrectified socket, and 2 subjects selected to use both sockets as their exit socket. Results seemed to indicate that more than one paradigm exists for shaping prosthetic sockets, and this paradigm may be helpful in understanding the mechanisms of socket fit. The alginate gel fabrication method was simpler than the traditional method. The method could be helpful in other countries where prosthetic care is lacking, may be helpful with new amputees, and may be helpful in typical clinics to reduce costs and free the prosthetist to focus more time on patient needs. PMID:18776945

An investigation on effects of amputee's physiological parameters on maximum pressure developed at the prosthetic socket interface using artificial neural network.

PubMed

Nayak, Chitresh; Singh, Amit; Chaudhary, Himanshu; Unune, Deepak Rajendra

2017-10-23

Technological advances in prosthetics have attracted the curiosity of researchers in monitoring design and developments of the sockets to sustain maximum pressure without any soft tissue damage, skin breakdown, and painful sores. Numerous studies have been reported in the area of pressure measurement at the limb/socket interface, though, the relation between amputee's physiological parameters and the pressure developed at the limb/socket interface is still not studied. Therefore, the purpose of this work is to investigate the effects of patient-specific physiological parameters viz. height, weight, and stump length on the pressure development at the transtibial prosthetic limb/socket interface. Initially, the pressure values at the limb/socket interface were clinically measured during stance and walking conditions for different patients using strain gauges placed at critical locations of the stump. The measured maximum pressure data related to patient's physiological parameters was used to develop an artificial neural network (ANN) model. The effects of physiological parameters on the pressure development at the limb/socket interface were examined using the ANN model. The analyzed results indicated that the weight and stump length significantly affects the maximum pressure values. The outcomes of this work could be an important platform for the design and development of patient-specific prosthetic socket which can endure the maximum pressure conditions at stance and ambulation conditions.

Evaluation of methods for calculating maximum allowable standing height in amputees competing in Paralympic athletics.

PubMed

Connick, M J; Beckman, E; Ibusuki, T; Malone, L; Tweedy, S M

2016-11-01

The International Paralympic Committee has a maximum allowable standing height (MASH) rule that limits stature to a pre-trauma estimation. The MASH rule reduces the probability that bilateral lower limb amputees use disproportionately long prostheses in competition. Although there are several methods for estimating stature, the validity of these methods has not been compared. To identify the most appropriate method for the MASH rule, this study aimed to compare the criterion validity of estimations resulting from the current method, the Contini method, and four Canda methods (Canda-1, Canda-2, Canda-3, and Canda-4). Stature, ulna length, demispan, sitting height, thigh length, upper arm length, and forearm length measurements in 31 males and 30 females were used to calculate the respective estimation for each method. Results showed that Canda-1 (based on four anthropometric variables) produced the smallest error and best fitted the data in males and females. The current method was associated with the largest error of those tests because it increasingly overestimated height in people with smaller stature. The results suggest that the set of Canda equations provide a more valid MASH estimation in people with a range of upper limb and bilateral lower limb amputations compared with the current method. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Upper extremity transplantation: current concepts and challenges in an emerging field.

PubMed

Elliott, River M; Tintle, Scott M; Levin, L Scott

2014-03-01

Loss of an isolated upper limb is an emotionally and physically devastating event that results in significant impairment. Patients who lose both upper extremities experience profound disability that affects nearly every aspect of their lives. While prosthetics and surgery can eventually provide the single limb amputee with a suitable assisting hand, limited utility, minimal haptic feedback, weight, and discomfort are persistent problems with these techniques that contribute to high rates of prosthetic rejection. Moreover, despite ongoing advances in prosthetic technology, bilateral amputees continue to experience high levels of dependency, disability, and distress. Hand and upper extremity transplantation holds several advantages over prosthetic rehabilitation. The missing limb is replaced with one of similar skin color and size. Sensibility, voluntary motor control, and proprioception are restored to a greater degree, and afford better dexterity and function than prosthetics. The main shortcomings of transplantation include the hazards of immunosuppression, the complications of rejection and its treatment, and high cost. Hand and upper limb transplantation represents the most commonly performed surgery in the growing field of Vascularized Composite Allotransplantation (VCA). As upper limb transplantation and VCA have become more widespread, several important challenges and controversies have emerged. These include: refining indications for transplantation, optimizing immunosuppression, establishing reliable criteria for monitoring, diagnosing, and treating rejection, and standardizing outcome measures. This article will summarize the historical background of hand transplantation and review the current literature and concepts surrounding it.

Effects of electrode size and spacing on sensory modalities in the phantom thumb perception area for the forearm amputees.

PubMed

Li, P; Chai, G H; Zhu, K H; Lan, N; Sui, X H

2015-01-01

Tactile sensory feedback plays a key role in accomplishing the dexterous manipulation of prosthetic hands for the amputees, and the non-invasive transcutaneous electrical nerve stimulation (TENS) of the phantom finger perception (PFP) area would be an effective way to realize sensory feedback clinically. In order to realize the high-spatial-resolution tactile sensory feedback in the PFP region, we investigated the effects of electrode size and spacing on the tactile sensations for potentially optimizing the surface electrode array configuration. Six forearm-amputated subjects were recruited in the psychophysical studies. With the diameter of the circular electrode increasing from 3 mm to 12 mm, the threshold current intensity was enhanced correspondingly under different sensory modalities. The smaller electrode could potentially lead to high sensation spatial resolution. Whereas, the smaller the electrode, the less the number of sensory modalities. For an Φ-3 mm electrode, it is even hard for the subject to perceive any perception modalities under normal stimulating current. In addition, the two-electrode discrimination distance (TEDD) in the phantom thumb perception area decreased with electrode size decreasing in two directions of parallel or perpendicular to the forearm. No significant difference of TEDD existed along the two directions. Studies in this paper would guide the configuration optimization of the TENS electrode array for potential high spatial-resolution sensory feedback.

Tissue viability monitoring: a multi-sensor wearable platform approach

NASA Astrophysics Data System (ADS)

Mathur, Neha; Davidson, Alan; Buis, Arjan; Glesk, Ivan

2016-12-01

Health services worldwide are seeking ways to improve patient care for amputees suffering from diabetes, and at the same time reduce costs. The monitoring of residual limb temperature, interface pressure and gait can be a useful indicator of tissue viability in lower limb amputees especially to predict the occurrence of pressure ulcers. This is further exacerbated by elevated temperatures and humid micro environment within the prosthesis which encourages the growth of bacteria and skin breakdown. Wearable systems for prosthetic users have to be designed such that the sensors are minimally obtrusive and reliable enough to faithfully record movement and physiological signals. A mobile sensor platform has been developed for use with the lower limb prosthetic users. This system uses an Arduino board that includes sensors for temperature, gait, orientation and pressure measurements. The platform transmits sensor data to a central health authority database server infrastructure through the Bluetooth protocol at a suitable sampling rate. The data-sets recorded using these systems are then processed using machine learning algorithms to extract clinically relevant information from the data. Where a sensor threshold is reached a warning signal can be sent wirelessly together with the relevant data to the patient and appropriate medical personnel. This knowledge is also useful in establishing biomarkers related to a possible deterioration in a patient's health or for assessing the impact of clinical interventions.

Context-Dependent Upper Limb Prosthesis Control for Natural and Robust Use.

PubMed

Amsuess, Sebastian; Vujaklija, Ivan; Goebel, Peter; Roche, Aidan D; Graimann, Bernhard; Aszmann, Oskar C; Farina, Dario

2016-07-01

Pattern recognition and regression methods applied to the surface EMG have been used for estimating the user intended motor tasks across multiple degrees of freedom (DOF), for prosthetic control. While these methods are effective in several conditions, they are still characterized by some shortcomings. In this study we propose a methodology that combines these two approaches for mutually alleviating their limitations. This resulted in a control method capable of context-dependent movement estimation that switched automatically between sequential (one DOF at a time) or simultaneous (multiple DOF) prosthesis control, based on an online estimation of signal dimensionality. The proposed method was evaluated in scenarios close to real-life situations, with the control of a physical prosthesis in applied tasks of varying difficulties. Test prostheses were individually manufactured for both able-bodied and transradial amputee subjects. With these prostheses, two amputees performed the Southampton Hand Assessment Procedure test with scores of 58 and 71 points. The five able-bodied individuals performed standardized tests, such as the box&block and clothes pin test, reducing the completion times by up to 30%, with respect to using a state-of-the-art pure sequential control algorithm. Apart from facilitating fast simultaneous movements, the proposed control scheme was also more intuitive to use, since human movements are predominated by simultaneous activations across joints. The proposed method thus represents a significant step towards intelligent, intuitive and natural control of upper limb prostheses.

[Mirror, mirror of the wall: mirror therapy in the treatment of phantom limbs and phantom limb pain].

PubMed

Casale, Roberto; Furnari, Anna; Lamberti, Raul Coelho; Kouloulas, Efthimios; Hagenberg, Annegret; Mallik, Maryam

2015-01-01

Phantom limb and phantom limb pain control are pivotal points in the sequence of intervention to bring the amputee to functional autonomy. The alterations of perception and sensation, the pain of the residual limb and the phantom limb are therefore aspects of amputation that should be taken into account in the "prise en charge" of these patients. Within the more advanced physical therapies to control phantom and phantom limb pain there is the use of mirrors (mirror therapy). This article willfocus on its use and on the possible side effects induced by the lack of patient selection and a conflict of body schema restoration through mirror therapy with concurrent prosthetic training and trauma acceptance. Advice on the need to select patients before treatment decisions, with regard to their psychological as well as clinical profile (including time since amputation and clinical setting), and the need to be aware of the possible adverse effects matching different and somehow conflicting therapeutic approaches, are put forward. Thus a coordinated sequence of diagnostic, prognostic and therapeutic procedures carried out by an interdisciplinary rehabilitation team that works globally on all patients' problems is fundamental in the management of amputees and phantom limb pain. Further studies and the development of a multidisciplinary network to study this and other applications of mirror therapy are needed.

Bionic ankle–foot prosthesis normalizes walking gait for persons with leg amputation

PubMed Central

Herr, Hugh M.; Grabowski, Alena M.

2012-01-01

Over time, leg prostheses have improved in design, but have been incapable of actively adapting to different walking velocities in a manner comparable to a biological limb. People with a leg amputation using such commercially available passive-elastic prostheses require significantly more metabolic energy to walk at the same velocities, prefer to walk slower and have abnormal biomechanics compared with non-amputees. A bionic prosthesis has been developed that emulates the function of a biological ankle during level-ground walking, specifically providing the net positive work required for a range of walking velocities. We compared metabolic energy costs, preferred velocities and biomechanical patterns of seven people with a unilateral transtibial amputation using the bionic prosthesis and using their own passive-elastic prosthesis to those of seven non-amputees during level-ground walking. Compared with using a passive-elastic prosthesis, using the bionic prosthesis decreased metabolic cost by 8 per cent, increased trailing prosthetic leg mechanical work by 57 per cent and decreased the leading biological leg mechanical work by 10 per cent, on average, across walking velocities of 0.75–1.75 m s−1 and increased preferred walking velocity by 23 per cent. Using the bionic prosthesis resulted in metabolic energy costs, preferred walking velocities and biomechanical patterns that were not significantly different from people without an amputation. PMID:21752817

Translating Research on Myoelectric Control into Clinics-Are the Performance Assessment Methods Adequate?

PubMed

Vujaklija, Ivan; Roche, Aidan D; Hasenoehrl, Timothy; Sturma, Agnes; Amsuess, Sebastian; Farina, Dario; Aszmann, Oskar C

2017-01-01

Missing an upper limb dramatically impairs daily-life activities. Efforts in overcoming the issues arising from this disability have been made in both academia and industry, although their clinical outcome is still limited. Translation of prosthetic research into clinics has been challenging because of the difficulties in meeting the necessary requirements of the market. In this perspective article, we suggest that one relevant factor determining the relatively small clinical impact of myocontrol algorithms for upper limb prostheses is the limit of commonly used laboratory performance metrics. The laboratory conditions, in which the majority of the solutions are being evaluated, fail to sufficiently replicate real-life challenges. We qualitatively support this argument with representative data from seven transradial amputees. Their ability to control a myoelectric prosthesis was tested by measuring the accuracy of offline EMG signal classification, as a typical laboratory performance metrics, as well as by clinical scores when performing standard tests of daily living. Despite all subjects reaching relatively high classification accuracy offline, their clinical scores varied greatly and were not strongly predicted by classification accuracy. We therefore support the suggestion to test myocontrol systems using clinical tests on amputees, fully fitted with sockets and prostheses highly resembling the systems they would use in daily living, as evaluation benchmark. Agreement on this level of testing for systems developed in research laboratories would facilitate clinically relevant progresses in this field.

Problems with Excessive Residual Lower Leg Length in Pediatric Amputees

PubMed Central

Osebold, William R; Lester, Edward L; Christenson, Donald M

2001-01-01

We studied six pediatric amputees with long below-knee residual limbs, in order to delineate their functional and prosthetic situations, specifically in relation to problems with fitting for dynamic-response prosthetic feet. Three patients had congenital pseudoarthrosis of the tibia secondary to neurofibromatosis, one had fibular hemimelia, one had a traumatic amputation, and one had amputation secondary to burns. Five patients had Syme's amputations, one had a Boyd amputation. Ages at amputation ranged from nine months to five years (average age 3 years 1 month). After amputation, the long residual below-knee limbs allowed fitting with only the lowest-profile prostheses, such as deflection plates. In three patients, the femoral dome to tibial plafond length was greater on the amputated side than on the normal side. To allow room for more dynamic-response (and larger) foot prostheses, two patients have undergone proximal and distal tibial-fibular epiphyseodeses (one at age 5 years 10 months, the other at 3 years 7 months) and one had a proximal tibial-fibular epiphyseodesis at age 7 years 10 months. (All three patients are still skeletally immature.) The families of two other patients are considering epiphyseodeses, and one patient is not a candidate (skeletally mature). Scanogram data indicate that at skeletal maturity the epiphyseodesed patients will have adequate length distal to their residual limbs to fit larger and more dynamic-response prosthetic feet. PMID:11813953

Strategies for providing upper extremity amputees with tactile and hand position feedback--moving closer to the bionic arm.

PubMed

Riso, R R

1999-01-01

A continuing challenge for prostheses developers is to replace the sensory function of the hand. This includes tactile sensitivity such as finger contact, grip force, object slippage, surface texture and temperature, as well as proprioceptive sense. One approach is sensory substitution whereby an intact sensory system such as vision, hearing or cutaneous sensation elsewhere on the body is used as an input channel for information related to the prosthesis. A second technique involves using electrical stimulation to deliver sensor derived information directly to the peripheral afferent nerves within the residual limb. Stimulation of the relevant afferent nerves can ultimately come closest to restoring the original sensory perceptions of the hand, and to this end, researchers have already demonstrated some degree of functionality of the transected sensory nerves in studies with amputee subjects. This paper provides an overview of different types of nerve interface components and the advantages and disadvantages of employing each of them in sensory feedback systems. Issues of sensory perception, neurophysiology and anatomy relevant to hand sensation and function are discussed with respect to the selection of the different types of nerve interfaces. The goal of this paper is to outline what can be accomplished for implementing sensation into artificial arms in the near term by applying what is present or presently attainable technology.

Heterotopic Ossification in Combat Amputees from Afghanistan and Iraq wars: Five Case Histories and Results from a Small Series of Patients

DTIC Science & Technology

2011-01-01

symptoms. This patient also had severe soft-tissue injuries to his nonamputated left arm that required a skin graft . Subse- quent to surgery, the...illustrates the use of preventive medi- cation and symptomatic HO following breakdown of a skin graft . This patient had bilateral transfemoral amputa...United States. He was fitted with prostheses and successfully learned to walk. This patient had a split-thickness skin graft on his right residual

Brain Biology Machine Initiative: Developing Innovative Novel Methods to Improve Neuro-Rehabilitation for Amputees and Treatment for Patients at Remote Sites with Acute Brain Injury

DTIC Science & Technology

2010-10-01

bode well for the future. The paper we submitted to the Journal of Neuroscience detailing the TVAG rabies tracer system was accepted with revisions...of brain electrical activity. Stas Kounitsky successfully completed the port of the new vector-additive implicit (VAI) method for the anisotropic ...Alternating Difference 14 Implicit (ADI) for isotropic head models, and the Vector Additive Implicit (VAI) for anisotropic head models. The ADI method

A Comparison of Health Outcomes for Combat Amputee and Limb Salvage Patients Injured in Iraq and Afghanistan Wars

DTIC Science & Technology

2013-01-01

Osteomyelitis 33a 33 47a 2 of 6 34 2 of 10 DVT and/or PE 16 42† 15 1 of 6 15 2 of 10 Cellulitis 25a 30 40a,c 1 of 6 20c 1 of 10 Septicemia 10a 15 4a 1 of 6 9 0...significantly increased ORs for any infection, osteomye- litis, and cellulitis relative to LS patients. They also had in- creased odds of mood

Final Report of the Lower Extremity Assessment Program (LEAP 99-2). Volume 2

DTIC Science & Technology

2000-08-01

conflict to see large-scale use of landmines. Anti- personnel landmines have played a significant role in every major conflict since. In the 1970s and 1980s ...combatants and civilians. From 1980 to 1993, the incidence of landmine-related injuries doubled, resulting in an estimated 2000 deaths or injuries per month...Antonelli, E. E., & Hislop , H., (1976). Energy cost of walking of amputees: The influence of level of amputation. Journal of Bone and Joint Surgery. 58-A, 42

System integration of pattern recognition, adaptive aided, upper limb prostheses

NASA Technical Reports Server (NTRS)

Lyman, J.; Freedy, A.; Solomonow, M.

1975-01-01

The requirements for successful integration of a computer aided control system for multi degree of freedom artificial arms are discussed. Specifications are established for a system which shares control between a human amputee and an automatic control subsystem. The approach integrates the following subsystems: (1) myoelectric pattern recognition, (2) adaptive computer aiding; (3) local reflex control; (4) prosthetic sensory feedback; and (5) externally energized arm with the functions of prehension, wrist rotation, elbow extension and flexion and humeral rotation.

Journal of Rehabilitation Research and Development. Volume 27 Number 3, Summer 1990

DTIC Science & Technology

1990-01-01

First 119. Reflex Sympathetic Dystrophy in an Amputee: Case St., Springfield, IL 62794-9265 Study. Odderson IR. Czerniecki JM, Arch Ph\\vs Med Rehabil 71...60206 Compiegne cedex. France Persons with Disabilities. Becker HA. et al.. hit J Rehabil Res 12(3):235-250. 1989. 201. Psychological Aspects of...Hearing Aid Treatment. Contact: Heather A. Becker . University of Texas at Austin. Borre S. Courtois J. hit J Rehabil Res 12(3):347-348. 1989. School of

Bilogy Machine Initiative: Developing Innovative Novel Methods to Improve Neuro-rehabilitation for Amputees and Treatment for Patients at Remote Sites with Acute Brain Injury

DTIC Science & Technology

2010-09-01

service to support the creation of both normative and pathological neuroinformatics databases. Project 3 Deliverable: The aim of this project is to...Gainesville, FL, 2010. D. Hammond, P. Vandergheynst, R. Gribonval, “ Wavelets on Graphs via Spectral Graph Theory,” Applied Computational and...the Phantom Experiments,” International Conference on Electrical Bioimpedance, April 4-8-, Gainesville, FL, 2010. 21 D. Hammond, “ Wavelets on

Development and validation of a 3D-printed interfacial stress sensor for prosthetic applications.

PubMed

Laszczak, P; Jiang, L; Bader, D L; Moser, D; Zahedi, S

2015-01-01

A novel capacitance-based sensor designed for monitoring mechanical stresses at the stump-socket interface of lower-limb amputees is described. It provides practical means of measuring pressure and shear stresses simultaneously. In particular, it comprises of a flexible frame (20 mm × 20 mm), with thickness of 4mm. By employing rapid prototyping technology in its fabrication, it offers a low-cost and versatile solution, with capability of adopting bespoke shapes of lower-limb residua. The sensor was first analysed using finite element analysis (FEA) and then evaluated using lab-based electromechanical tests. The results validate that the sensor is capable of monitoring both pressure and shear at stresses up to 350 kPa and 80 kPa, respectively. A post-signal processing model is developed to induce pressure and shear stresses, respectively. The effective separation of pressure and shear signals can be potentially advantageous for sensor calibration in clinical applications. The sensor also demonstrates high linearity (approx. 5-8%) and high pressure (approx. 1.3 kPa) and shear (approx. 0.6 kPa) stress resolution performance. Accordingly, the sensor offers the potential for exploitation as an assistive tool to both evaluate prosthetic socket fitting in clinical settings and alert amputees in home settings of excessive loading at the stump-socket interface, effectively preventing stump tissue breakdown at an early stage. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

Evaluation of 3D printed anatomically scalable transfemoral prosthetic knee.

PubMed

Ramakrishnan, Tyagi; Schlafly, Millicent; Reed, Kyle B

2017-07-01

This case study compares a transfemoral amputee's gait while using the existing Ossur Total Knee 2000 and our novel 3D printed anatomically scalable transfemoral prosthetic knee. The anatomically scalable transfemoral prosthetic knee is 3D printed out of a carbon-fiber and nylon composite that has a gear-mesh coupling with a hard-stop weight-actuated locking mechanism aided by a cross-linked four-bar spring mechanism. This design can be scaled using anatomical dimensions of a human femur and tibia to have a unique fit for each user. The transfemoral amputee who was tested is high functioning and walked on the Computer Assisted Rehabilitation Environment (CAREN) at a self-selected pace. The motion capture and force data that was collected showed that there were distinct differences in the gait dynamics. The data was used to perform the Combined Gait Asymmetry Metric (CGAM), where the scores revealed that the overall asymmetry of the gait on the Ossur Total Knee was more asymmetric than the anatomically scalable transfemoral prosthetic knee. The anatomically scalable transfemoral prosthetic knee had higher peak knee flexion that caused a large step time asymmetry. This made walking on the anatomically scalable transfemoral prosthetic knee more strenuous due to the compensatory movements in adapting to the different dynamics. This can be overcome by tuning the cross-linked spring mechanism to emulate the dynamics of the subject better. The subject stated that the knee would be good for daily use and has the potential to be adapted as a running knee.

Comparison of nonmicroprocessor knee mechanism versus C-Leg on Prosthesis Evaluation Questionnaire, stumbles, falls, walking tests, stair descent, and knee preference.

PubMed

Kahle, Jason T; Highsmith, M Jason; Hubbard, Sandra L

2008-01-01

This study compared subjects' performance with a nonmicroprocessor knee mechanism (NMKM) versus a C-Leg on nine clinically repeatable evaluative measures. We recorded data on subjects' performance while they used an accommodated NMKM and, following a 90-day accommodation period, the C-Leg in a convenience sample of 19 transfemoral (TF) amputees (mean age 51 +/- 19) from an outpatient prosthetic clinic. We found that use of the C-Leg improved function in all outcomes: (1) Prosthesis Evaluation Questionnaire scores increased 20% (p = 0.007), (2) stumbles decreased 59% (p = 0.006), (3) falls decreased 64% (p = 0.03), (4) 75 m self-selected walking speed on even terrain improved 15% (p = 0.03), (5) 75 m fastest possible walking speed (FPWS) on even terrain improved 12% (p = 0.005), (6) 38 m FPWS on uneven terrain improved 21% (p < 0.001), (7) 6 m FPWS on even terrain improved 17% (p = 0.001), (8) Montreal Rehabilitation Performance Profile Performance Composite Scores for stair descent increased for 12 subjects, and (9) the C-Leg was preferred over the NMKM by 14 subjects. Four limited community ambulators (Medicare Functional Classification Level [MFCL] K2) increased their ambulatory functional level to unlimited community ambulation (MFCL K3). Objective evaluative clinical measures are vital for justifying the medical necessity of knee mechanisms for TF amputees. Use of the C-Leg improves performance and quality of life and can increase MFCL and community ambulation level.

Ultrasonic longitudinal waves to monitor the integration of titanium rods with host bone

NASA Astrophysics Data System (ADS)

Wang, Wentao; Lynch, Jerome P.

2017-04-01

Osseointegrated prostheses which integrate the prosthesis directly to the limb bone are being developed for patients that are unable to wear traditional socket prostheses. While osseointegration of the prosthesis offers amputees improvement in their quality of life, there remains a need to better understand the integration process that occurs between the bone and the prosthesis. Quantification of the degree of integration is important to track the recuperation process of the amputee, guide physical therapy regimes, and to identify when the state of integration may change (due to damage to the bone). This study explores the development of an assessment strategy for quantitatively assessing the degree of integration between an osseointegrated prosthesis and host bone. Specifically, the strategy utilizes a titanium rod prosthesis as a waveguide with guided waves used to assess the degree of integration. By controlling waveforms launched by piezoelectric wafers bonded on the percutaneous tip of the prosthesis, body waves are introduced into the waveguide with wave reflections at the boneprosthesis interface recorded by the same array. Changes in wave energy are correlated to changes at the contact interface between the titanium rod and the bone material. Both simulation and experimental tests are presented in this paper. Experimental testing is performed using a high-density polyethylene (HDPE) host because the elastic modulus and density of HDPE are close to that of human and animal bone. Results indicate high sensitivity of the longitudinal wave energy to rod penetration depth and confinement stress issued by the host bone.

[Body Integrity Identity Disorder (BIID): interrogation of patients and theories for explanation].

PubMed

Kasten, E

2009-01-01

Apotemnophilia, Amputee Identity Disorder or Body Integrity Identity Disorder (BIID) is the intensive feeling that the body will be "more complete" after amputation of a limb. The article disputes the question of matching personality characteristics of these subjects and asks for motives. Based on reports of nine individuals, triggering experiences are referred. In contrast to other children, often these subjects were fascinated by the sight of a handicapped person. In the article is investigated, whether the concerned limb showed more affections. Described is typical pretending behavior. Parallels to body dysmorphic disorder (BDD), fetishism, or delusions are investigated. These were minor, in most cases the wish was fixated on a specific limb, the subjects were aware of the abnormity of their desire and quarreled with the pros and cons. Sexual motives were found in one third. Some of the interviewed persons were in medical or psychological therapy; this did not let the desire disappear. In several BIID sufferers the wish for amputation changed, e. g. from the left to the right leg. This finding is not in accordance with the brain-dysfunction-theory. These people rather have an ideal of a "perfect" body minus one arm or leg. Most admire the beauty of a stump, and see amputees as "heroes" who still master their life in spite of their handicap. BIID is not a homogenous disturbance, one should separate three axes: 1. Strength of neuronal dysfunction, 2. Psychic components (e. g. secondary morbid gain) and 3. Intensity of sexual interests.

Amputation effects on the underlying complexity within transtibial amputee ankle motion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wurdeman, Shane R., E-mail: shanewurdeman@gmail.com; Advanced Prosthetics Center, Omaha, Nebraska 68134; Myers, Sara A.

2014-03-15

The presence of chaos in walking is considered to provide a stable, yet adaptable means for locomotion. This study examined whether lower limb amputation and subsequent prosthetic rehabilitation resulted in a loss of complexity in amputee gait. Twenty-eight individuals with transtibial amputation participated in a 6 week, randomized cross-over design study in which they underwent a 3 week adaptation period to two separate prostheses. One prosthesis was deemed “more appropriate” and the other “less appropriate” based on matching/mismatching activity levels of the person and the prosthesis. Subjects performed a treadmill walking trial at self-selected walking speed at multiple points ofmore » the adaptation period, while kinematics of the ankle were recorded. Bilateral sagittal plane ankle motion was analyzed for underlying complexity through the pseudoperiodic surrogation analysis technique. Results revealed the presence of underlying deterministic structure in both prostheses and both the prosthetic and sound leg ankle (discriminant measure largest Lyapunov exponent). Results also revealed that the prosthetic ankle may be more likely to suffer loss of complexity than the sound ankle, and a “more appropriate” prosthesis may be better suited to help restore a healthy complexity of movement within the prosthetic ankle motion compared to a “less appropriate” prosthesis (discriminant measure sample entropy). Results from sample entropy results are less likely to be affected by the intracycle periodic dynamics as compared to the largest Lyapunov exponent. Adaptation does not seem to influence complexity in the system for experienced prosthesis users.« less

Kinematic adaptations to tripedal locomotion in dogs.

PubMed

Goldner, B; Fuchs, A; Nolte, I; Schilling, N

2015-05-01

Limb amputation often represents the only treatment option for canine patients with certain diseases or injuries of the appendicular system. Previous studies have investigated adaptations to tripedal locomotion in dogs but there is a lack of understanding of biomechanical compensatory mechanisms. This study evaluated the kinematic differences between quadrupedal and tripedal locomotion in nine healthy dogs running on a treadmill. The loss of the right pelvic limb was simulated using an Ehmer sling. Kinematic gait analysis included spatio-temporal comparisons of limb, joint and segment angles of the remaining pelvic and both thoracic limbs. The following key parameters were compared between quadrupedal and tripedal conditions: angles at touch-down and lift-off, minimum and maximum joint angles, plus range of motion. Significant differences in angular excursion were identified in several joints of each limb during both stance and swing phases. The most pronounced differences concerned the remaining pelvic limb, followed by the contralateral thoracic limb and, to a lesser degree, the ipsilateral thoracic limb. The thoracic limbs were, in general, more retracted, consistent with pelvic limb unloading and previous observations of bodyweight re-distribution in amputees. Proximal limb segments showed more distinct changes than distal ones. Particularly, the persistently greater anteversion of the pelvis probably affects the axial system. Overall, tripedal locomotion requires concerted kinematic adjustments of both the appendicular and axial systems, and consequently preventive, therapeutic and rehabilitative care of canine amputees should involve the whole musculoskeletal apparatus. Copyright © 2015 Elsevier Ltd. All rights reserved.

ECONOMIC EVALUATIONS OF INTERVENTIONS FOR TRANSTIBIAL AMPUTEES: A SCOPING REVIEW OF COMPARATIVE STUDIES.

PubMed

Highsmith, M Jason; Kahle, Jason T; Lewandowski, Amanda; Klenow, Tyler D; Orriola, John J; Miro, Rebecca M; Hill, Owen T; Raschke, Sylvia Ursula; Orendurff, Michael S; Highsmith, James T; Sutton, Bryce S

2016-09-01

Transtibial amputation (TTA) is life-altering emotionally, functionally, and economically. The economic impact to all stakeholders is largely unknown, as is the cost-effectiveness of prosthetic intervention. This scoping report's purpose was to determine if there is sufficient evidence to conduct a formal systematic review or meta-analysis in any particular prosthetic intervention area and to determine if any evidence statements could be synthesized relative to economic evaluation of interventions provided to patients with TTA. The scoping review revealed six articles representing three topical areas of transtibial care: Care Models, Prosthetic Treatment, and Prosthetic Sockets. All six articles were cost-identification or cost-consequence design and included a total of 704 subjects. Presently, it can be concluded with moderate confidence that specific weight-bearing and total-contact sockets for transtibial amputees are functionally and economically equivalent in the short term when costs, delivery time, and all stakeholder perspectives are considered. Long-term socket outcomes are relatively unexplored. Further primary research is needed beyond this to determine cost-effectiveness for other areas of transtibial prosthetic care although clinical outcomes are somewhat established through systematic review and meta-analysis in other areas of care. Conversely, evaluation of narrative economic reports relative to transtibial care may be sufficient to warrant further analysis. Guidance from the profession may also be useful in devising a strategy for how to assure economic analyses are a routine element of future prosthetic science.

Agency over Phantom Limb Enhanced by Short-Term Mirror Therapy

PubMed Central

Imaizumi, Shu; Asai, Tomohisa; Koyama, Shinichi

2017-01-01

Most amputees experience phantom limb, whereby they feel that the amputated limb is still present. In some cases, these experiences include pain that can be alleviated by “mirror therapy.” Mirror therapy consists of superimposing a mirrored image of the moving intact limb onto the phantom limb. This therapy provides a closed loop between the motor command to the amputated limb and its predicted visual feedback. This loop is also involved in the sense of agency, a feeling of controlling one’s own body. However, it is unclear how mirror therapy is related to the sense of agency over a phantom limb. Using mirror therapy, we investigated phantom limb pain and the senses of agency and ownership (i.e., a feeling of having one’s own body) of the phantom limb. Nine upper-limb amputees, five of whom reported recent phantom limb pain, underwent a single 15-min trial of mirror therapy. Before and after the trial, the participants completed a questionnaire regarding agency, ownership, and pain related to their phantom limb. They reported that the sense of agency over the phantom limb increased following the mirror therapy trial, while the ownership slightly increased but not as much as did the agency. The reported pain did not change; that is, it was comparably mild before and after the trial. These results suggest that short-term mirror therapy can, at least transiently, selectively enhance the sense of agency over a phantom limb, but may not alleviate phantom limb pain. PMID:29046630

[Study of bone mass with dual energy x-ray absorptiometry in a population of 99 lower limb amputees].

PubMed

Leclercq, M M; Bonidan, O; Haaby, E; Pierrejean, C; Sengler, J

2003-02-01

Osteopenia in lower extremity amputation is described with an increased risk of fracture and it seems to be interesting to study bone mass in a population of 99 amputees of limb. We studied the bone mass with Dual Energy Xray Absorptiometry in patients with limb amputation, above and under knee and who have been treated in the rehabilitation department of Mulhouse's hospital and more specifically the percentage of the difference of the mesure between amputed and non amputed side and the influence on this mesure of several factors like sexe; age; diabetes mellitus; delay of amputation; aetiology and use of prosthesis. For all the population, we find lower values of BMD (Bone mineral density) for femoral neck -10.4% +/- 12.2 (P < 0,001) and trochanter -14.9% +/- 14.5 (P < 0,001) between amputated and non amputated side, and also comparing with normal population -19.9% +/- 18.8 (P < 0,001) for femoral neck and -8.8% +/- 22 (P < 0,001) for trochanter.There is no influence of sexe, age, and time since amputation on BMD. The study of sub-groupes shows that the loss of bone mass is depending on traumatic amputation, the level of amputation (above knee) and when prothetis doesn't fit. Arteritis or diabetis are not pejoratif factors. This work confirms the mechanical factors as an important parameter of bone loss in the limb amputation.

Agency over Phantom Limb Enhanced by Short-Term Mirror Therapy.

PubMed

Imaizumi, Shu; Asai, Tomohisa; Koyama, Shinichi

2017-01-01

Most amputees experience phantom limb, whereby they feel that the amputated limb is still present. In some cases, these experiences include pain that can be alleviated by "mirror therapy." Mirror therapy consists of superimposing a mirrored image of the moving intact limb onto the phantom limb. This therapy provides a closed loop between the motor command to the amputated limb and its predicted visual feedback. This loop is also involved in the sense of agency, a feeling of controlling one's own body. However, it is unclear how mirror therapy is related to the sense of agency over a phantom limb. Using mirror therapy, we investigated phantom limb pain and the senses of agency and ownership (i.e., a feeling of having one's own body) of the phantom limb. Nine upper-limb amputees, five of whom reported recent phantom limb pain, underwent a single 15-min trial of mirror therapy. Before and after the trial, the participants completed a questionnaire regarding agency, ownership, and pain related to their phantom limb. They reported that the sense of agency over the phantom limb increased following the mirror therapy trial, while the ownership slightly increased but not as much as did the agency. The reported pain did not change; that is, it was comparably mild before and after the trial. These results suggest that short-term mirror therapy can, at least transiently, selectively enhance the sense of agency over a phantom limb, but may not alleviate phantom limb pain.

The effect of mirror therapy on the management of phantom limb pain.

PubMed

Yıldırım, Meltem; Kanan, Nevin

2016-07-01

In the last two decades, mirror therapy has become a frequently used method of managing phantom limb pain (PLP). However, the role of nurses in mirror therapy has not yet been well defined. This study examined the effect of mirror therapy on the management of PLP, and discusses the importance of mirror therapy in the nursing care of amputee patients. This quasi-experimental study was conducted in the pain management department of a university hospital and a prosthesis clinic in İstanbul, Turkey, with 15 amputee patients who had PLP. Forty minutes of practical mirror therapy training was given to the patients and they were asked to practice at home for 4 weeks. Patients were asked to record the severity of their PLP before and after the therapy each day using 0-10 Numeric Pain Intensity Scale. Mirror therapy practiced for 4 weeks provided a significant decrease in severity of PLP. There was no significant relationship between the effect of mirror therapy and demographic, amputation or PLP-related characteristics. Patients who were not using prosthesis had greater benefit from mirror therapy. Mirror therapy can be used as an adjunct to medical and surgical treatment of PLP. It is a method that patients can practice independently, enhancing self-control over phantom pain. As mirror therapy is a safe, economical, and easy-to-use treatment method, it should be considered in the nursing care plan for patients with PLP.

Mobility and satisfaction with a microprocessor-controlled knee in moderately active amputees: A multi-centric randomized crossover trial.

PubMed

Lansade, Céline; Vicaut, Eric; Paysant, Jean; Ménager, Doménico; Cristina, Marie-Christine; Braatz, Frank; Domayer, Stephan; Pérennou, Dominic; Chiesa, Gérard

2018-05-14

Microprocessor-controlled knees are generally prescribed and reimbursed for active amputees. Recent studies suggested that this technology could be useful for amputees with moderate activity level. We compared the efficiency of a microprocessor-controlled knee (MPK, Kenevo, Otto Bock) and non-MPKs (NMPKs) in these indications. A multi-centric randomized crossover trial was conducted in 16 hospitals from 3 European countries. Participants were randomized to an MPK-NMPK sequence, testing the MPK for 3 months and the NMPK for 1 month, or to an NMPK-MPK sequence, testing the NMPK for 1 month and the MPK for 3 months. Dynamic balance, the main criteria, was assessed with the Timed-Up and Go test (TUG), functional mobility with the Locomotor Capability Index (LCI-5), quality of life with the Medical Outcomes Study Short Form 36 v2 (SF-36v2) and satisfaction with the Quebec User Evaluation of Satisfaction with Assistive Technology 2.0. The occurrence of falls was monitored during the last month of trial. Analysis was by intent-to-treat and per-protocol (PP). We recruited 35 individuals with transfemoral amputation or knee disarticulation (27 males; mean age 65.6years [SD 10.1]). On PP analysis, dynamic balance and functional mobility were improved with the MPK, as shown by a reduced median TUG time (from 21.4s [Q1-Q3 19.3-26.6] to 17.9s [15.4-22.7], P=0.001) and higher mean global LCI-5 (from 40.4 [SD 7.6] to 42.8 [6.2], P=0.02). Median global satisfaction score increased (from 3.9 [Q1-Q3 3.8-4.4] to 4.7 [4.1-4.9], P=0.001) and quality of life was improved for the mental component summary of the SF-36v2 (median score from 53.3 [Q1-Q3 47.8-60.7] to 60.2 [51.6-62.6], P=0.03) and physical component summary but not significantly (mean score from 44.1 [SD 6.3] to 46.3 [7.0], P=0.08). Monitoring of adverse events including falls revealed no differences between both assessed devices. This study enhances the level of evidence to argue equal opportunity for all individuals with transfemoral amputation or knee disarticulation, regardless of their mobility grade, to be provided with appropriate prostheses. Copyright © 2018. Published by Elsevier Masson SAS.

Brachial plexus injury management through upper extremity amputation with immediate postoperative prostheses.

PubMed

Malone, J M; Leal, J M; Underwood, J; Childers, S J

1982-02-01

Management of patients with brachial plexus injuries requires a team approach so that all aspects of their care are addressed simultaneously. This report examines elective amputation and prosthetic rehabilitation in a patient with brachial plexus avulsion of the left arm. The best possibility for good prosthetic rehabilitation is the early application of prosthetic devices with intensive occupational therapy. Using this type of approach, we have achieved significant improvement in amputation rehabilitation of upper extremity amputees treated with immediate postoperative conventional electric and myoelectric prostheses.

Managing residual limb hyperhidrosis in wounded warriors.

PubMed

Pace, Sarah; Kentosh, Joshua

2016-06-01

Residual limb dermatologic problems are a common concern among young active traumatic amputee patients who strive to maintain an active lifestyle. Hyperhidrosis of residual limbs is a recognized inciting factor that often contributes to residual limb dermatoses and is driven by the design of the prosthetic liner covering the residual limb. Treatment of hyperhidrosis in this population presents a unique challenge. Several accepted treatments of hyperhidrosis can offer some relief but have been limited by lack of results or side-effect profiles. Microwave thermal ablation has presented an enticing potential for residual limb hyperhidrosis.

From Wounded Warrior To Civilian Employee: A Workplace Reference Guide For Managers And Supervisors

DTIC Science & Technology

2012-03-12

go away, repeated vomiting or nausea, convulsions or seizures, an inability to awaken from sleep, dilation of one or both pupils of the eyes, slurred...while speaking with an amputee or burn victim  Do not pet or feed someone’s service dog Workplace Conduct - Mobility Issues  Ensure the workplace...side of guide dog and do not touch a person’s dog or walking cane  If you are leaving a person who is blind, inform him/her you are leaving  If

Gait Training Interventions for Lower Extremity Amputees: A Systematic Literature Review

PubMed Central

Highsmith, M. Jason; Andrews, Casey R.; Millman, Claire; Fuller, Ashley; Kahle, Jason T.; Klenow, Tyler D.; Lewis, Katherine L.; Bradley, Rachel C.; Orriola, John J.

2016-01-01

Lower extremity (LE) amputation patients who use prostheses have gait asymmetries and altered limb loading and movement strategies when ambulating. Subsequent secondary conditions are believed to be associated with gait deviations and lead to long-term complications that impact function and quality of life as a result. The purpose of this study was to systematically review the literature to determine the strength of evidence supporting gait training interventions and to formulate evidence statements to guide practice and research related to therapeutic gait training for lower extremity amputees. A systematic review of three databases was conducted followed by evaluation of evidence and synthesis of empirical evidence statements (EES). Eighteen manuscripts were included in the review, which covered two areas of gait training interventions: 1) overground and 2) treadmill-based. Eight EESs were synthesized. Four addressed overground gait training, one covered treadmill training, and three statements addressed both forms of therapy. Due to the gait asymmetries, altered biomechanics, and related secondary consequences associated with LE amputation, gait training interventions are needed along with study of their efficacy. Overground training with verbal or other auditory, manual, and psychological awareness interventions was found to be effective at improving gait. Similarly, treadmill-based training was found to be effective: 1) as a supplement to overground training; 2) independently when augmented with visual feedback and/or body weight support; or 3) as part of a home exercise plan. Gait training approaches studied improved multiple areas of gait, including sagittal and coronal biomechanics, spatiotemporal measures, and distance walked. PMID:28066520

Effect of prosthetic alignment changes on socket reaction moment impulse during walking in transtibial amputees

PubMed Central

Kobayashi, Toshiki; Orendurff, Michael S.; Arabian, Adam K.; Rosenbaum-Chou, Teri G.; Boone, David A.

2014-01-01

The alignment of a lower limb prosthesis affects the way load is transferred to the residual limb through the socket, and this load is critically important for the comfort and function of the prosthesis. Both magnitude and duration of the moment are important factors that may affect the residual limb health. Moment impulse is a well-accepted measurement that incorporates both factors via moment–time integrals. The aim of this study was to investigate the effect of alignment changes on the socket reaction moment impulse in transtibial prostheses. Ten amputees with transtibial prostheses participated in this study. The socket reaction moment impulse was measured at a self-selected walking speed using a Smart Pyramid™ in 25 alignment conditions, including a nominal alignment (clinically aligned by a prosthetist), as well as angle malalignments of 2°, 4° and 6° (abduction, adduction, extension and flexion) and translation malalignments of 5 mm, 10 mm and 15 mm (lateral, medial, anterior and posterior). The socket reaction moment impulse of the nominal alignment was compared for each condition. The relationship between the alignment and the socket reaction moment impulse was clearly observed in the coronal angle, coronal translation and sagittal translation alignment changes. However, this relationship was not evident in the sagittal angle alignment changes. The results of this study suggested that the socket reaction moment impulse could potentially serve as a valuable parameter to assist the alignment tuning process for transtibial prostheses. Further study is needed to investigate the influence of the socket reaction moment impulse on the residual limb health. PMID:24612718

Prosthetics socket that incorporates an air splint system focusing on dynamic interface pressure.

PubMed

Razak, Nasrul Anuar Abd; Osman, Noor Azuan Abu; Gholizadeh, Hossein; Ali, Sadeeq

2014-08-01

The interface pressure between the residual limb and prosthetic socket has a significant effect on an amputee's satisfaction and comfort. This paper presents the design and performance of a new prosthetic socket that uses an air splint system. The air splint prosthetic socket system was implemented by combining the air splint with a pressure sensor that the transhumeral user controls through the use of a microcontroller. The modular construction of the system developed allows the FSR pressure sensors that are placed inside the air splint socket to determine the required size and fitting for the socket used. Fifteen transhumeral amputees participated in the study. The subject's dynamic pressure on the socket that's applied while wearing the air splint systems was recorded using F-socket transducers and microcontroller analysis. The values collected by the F-socket sensor for the air splint prosthetic socket system were determined accordingly by comparing the dynamic pressure applied using statically socket. The pressure volume of the air splint fluctuated and was recorded at an average of 38 kPa (2.5) to 41 kPa (1.3) over three hours. The air splint socket might reduce the pressure within the interface of residual limb. This is particularly important during the daily life activities and may reduce the pain and discomfort at the residual limb in comparison to the static socket. The potential development of an auto-adjusted socket that uses an air splint system as the prosthetic socket will be of interest to researchers involved in rehabilitation engineering, prosthetics and orthotics.

Traumatic below-elbow amputations.

PubMed

Freeland, Alan E; Psonak, Rick

2007-02-01

Prehension, intelligence, and erect posture distinguish humans from lower animals. Hands are instrumental for our survival and welfare. We use our hands when we work, recreate, and communicate. A handshake, a touch, a sign, or signal has significant social and communicative meanings. Hands play a major role in defining the skill level of our activities and our level of social expression and integration. Indeed, refined psychomotor precision of hand function may distinguish some individuals among us, gifting society with its more skilled craftsmen, surgeons, artisans, musicians, athletes, and the like in a highly digital world. For others, their hands are critical in providing and caring for their families. Injury severity scores may identify the majority of patients that require amputation; however, injury severity scoring system predictions in individual patients may be problematic and should be used with caution. Amputees require comprehensive multidisciplinary treatment and compassion so that they can successfully overcome their losses. Ultimately, the patients must change, adjust, and adapt to successfully reintegrate themselves into their families, peer groups, job settings, and society as a whole. Early amputation may decrease the incidence and severity of phantom pain compared to amputation after the failure of reconstruction. Early prosthetic fitting, training, and physical rehabilitation; early psychological and sociological support; and early return to work facilitate successful functional recovery. Psychological recovery may be a more arduous and extended process than physical recovery. We must teach our amputees from the outset to use their losses as an incentive for success, assist them to regain their quality of life, and encourage them to act as role models for and to educate others.

Therapeutic and Economic Impact of a Modern Amputation Program

PubMed Central

Malone, James M.; Moore, Wesley S.; Goldstone, Jerry; Malone, Sandee J.

1979-01-01

The experience with 142 below-knee amputations for vascular occlusive disease and/or diabetes mellitus in 133 patients has been reviewed. The program utilized Xenon133 skin bloodflow measurement for the selection of amputation level, emphasized the use of the long posterior skin flap as an important part of surgical technique, and employed immediate postoperative prosthesis with accelerated rehabilitation for postoperative management. The results of this program yielded a 0% postoperative mortality, 89% amputation healing, and 100% prosthesis rehabilitation of all unilateral below-knee amputees, and 93% rehabilitation of all bilateral below-knee amputees. The average time interval between amputation and fitting of a permanent prosthesis was 32 days. The use of Xenon133 clearance as a measurement of capillary skin bloodflow for purposes of amputation level selection continues to be valid. All amputations with flows in excess of 2.6 ml/100 g tissue/min healed primarily, including the last 58 consecutive amputations. The total amputation of the 172 hospital V.A. system was surveyed and a cost analysis, based upon duration of postamputation hospitalization, comparing immediate postoperative prosthesis with conventional techniques, was performed. The savings to the system, taking into account start-up and maintenance costs for a program which employs immediate postoperative prosthesis, was projected to be $80,000,000 over five years. We conclude that a modern amputation program employing Xenon133 clearance for amputation level selection and immediate postoperative prosthesis with accelerated rehabilitation is well justified based upon reduced morbidity, negligable mortality, and optimum patient prosthetic rehabilitation at a marked reduction in overall cost. PMID:453951

Recent advancements in prosthetic hand technology.

PubMed

Saikia, Angana; Mazumdar, Sushmi; Sahai, Nitin; Paul, Sudip; Bhatia, Dinesh; Verma, Suresh; Rohilla, Punit Kumar

2016-07-01

Recently, significant advances over the past decade have been made in robotics, artificial intelligence and other cognitive related fields, allowing development of highly sophisticated bio-mimetic robotics systems. In addition, enormous number of robots have been designed and assembled by explicitly realising their biological oriented behaviours. To enhance skill behaviours and adequate grasping abilities in these devices, a new phase of dexterous hands has been developed recently with bio-mimetically oriented and bio-inspired functionalities. The aim in writing this review paper is to present a detailed insight towards the development of the bio-mimetic based dexterous robotic multi-fingered artificial hand. An "ideal" upper limb prosthesis should be perceived as a part of their natural body by the amputee and should replicate sensory-motor capabilities of the amputated limb. Upper-limb amputations are most often the result of sudden trauma to the body, although they also can be caused by malignancy, congenital deficiencies and vascular diseases. This paper discusses the different bio-mimetic approaches using a framework that permits for a common description of biological and technical based hand manipulation behaviour. In particular, the review focuses on a number of developments in the inspired robotic systems. In conclusion, the study found that a huge amount of research efforts in terms of kinematics, dynamics, modelling and control methodologies are being put in to improve the present hand technology, thereby providing more functionality to the prosthetic limb of the amputee. This would improve their quality-of-life and help in performing activities of daily living (ADL) tasks with comparative ease in the near future.

The biomechanics of one-footed vertical jump performance in unilateral trans-tibial amputees.

PubMed

Strike, S C; Diss, C

2005-04-01

This study investigated vertical jumps from single support for two trans-tibial amputees from a standing position. The mechanisms used to achieve flight and the compensatory mechanisms used in the production of force in the absence of plantarflexors are detailed. Two participants completed countermovement maximum vertical jumps from the prosthetic and the sound limbs. The jumps were recorded by a 7-camera 512 VICON motion analysis system integrated with a Kistler forceplate. Flight height was 5 cm jumping from the prosthetic side and 18-19 cm from the sound side. The countermovement was shallower and its duration was less on the prosthetic side compared to the sound side. The reduced and passive range of motion at the prosthesis resulted in an asymmetrical countermovement for both participants with the knee and ankle joints most affected. The duration of the push-off phase was not consistently affected. At take-off the joints on the sound side reached close to full extension while on the prosthetic side they remained more flexed. Joint extension velocity in the push-off phase was similar for both participants on the sound side, though the timing for participant 2 illustrated earlier peaks. The pattern of joint extension velocity was not a smooth proximal to distal sequence on the prosthetic side. The magnitude and timing of the inter-segment extensor moments were asymmetrical for both subjects. The power pattern was asymmetrical in both the countermovement and push-off phases; the lack of power generation at the ankle affected that produced at the remaining joints.

Effectiveness of mirror therapy, motor imagery, and virtual feedback on phantom limb pain following amputation: A systematic review.

PubMed

Herrador Colmenero, Laura; Perez Marmol, Jose Manuel; Martí-García, Celia; Querol Zaldivar, María de Los Ángeles; Tapia Haro, Rosa María; Castro Sánchez, Adelaida María; Aguilar-Ferrándiz, María Encarnación

2018-06-01

Phantom limb pain is reported in 50%-85% of people with amputation. Clinical interventions in treating central pain, such as mirror therapy, motor imagery, or virtual visual feedback, could redound in benefits to amputee patients with phantom limb pain. To provide an overview of the effectiveness of different techniques for treating phantom limb pain in amputee patients. Systematic review. A computerized literature search up to April 2017 was performed using the following databases: PubMed, Scopus, CINAHL, MEDLINE, ProQuest, PEDro, EBSCOhost, and Cochrane Plus. Methodological quality and internal validity score of each study were assessed using PEDro scale. For data synthesis, qualitative methods from the Cochrane Back Review Group were applied. In all, 12 studies met our inclusion criteria, where 9 were rated as low methodological quality and 3 rated moderate quality. All studies showed a significant reduction in pain, but there was heterogeneity among subjects and methodologies and any high-quality clinical trial (PEDro score ≤8; internal validity score ≤5) was not found. Mirror therapy, motor imaginary, and virtual visual feedback reduce phantom limb pain; however, there is limited scientific evidence supporting their effectiveness. Future studies should include designs with more solid research methods, exploring short- and long-term benefits of these therapies. Clinical relevance This systematic review investigates the effectiveness of mirror therapy, motor imagery, and virtual visual feedback on phantom limb pain, summarizing the currently published trials and evaluating the research quality. Although these interventions have positive benefits in phantom limb pain, there is still a lack of evidence for supporting their effectiveness.

The effects of mirror therapy on pain and motor control of phantom limb in amputees: A systematic review.

PubMed

Barbin, J; Seetha, V; Casillas, J M; Paysant, J; Pérennou, D

2016-09-01

Phantom limb pain (PLP) is a major problem after limb amputation. Mirror therapy (MT) is a non-pharmacological treatment using representations of movement, the efficacy of which in reducing PLP remains to be clarified. Here, we present the first systematic review on MT efficacy in PLP and phantom limb movement (PLM) in amputees (lower or upper limb). A search on Medline, Cochrane Database and Embase, crossing the keywords "Phantom Limb" and "Mirror Therapy" found studies which were read and analyzed according the PRISMA statement. Twenty studies were selected, 12 on the subject of MT and PLP, 3 on MT and PLM, 5 on MT and both (PLP and PLM). Among these 20 studies, 5 were randomized controlled trials (163 patients), 6 prospective studies (55 patients), 9 case studies (40 patients) and methodologies were heterogeneous. Seventeen of the 18 studies reported the efficacy of MT on PLP, but with low levels of evidence. One randomized controlled trial did not show any significant effect of MT. As to the effect of MT on PLM, the 8 studies concerned reported effectiveness of MT: 4 with a low level of evidence and 4 with a high level of evidence. An alternative to visual illusion seems to be tactile or auditory stimulation. We cannot recommend MT as a first intention treatment in PLP. The level of evidence is insufficient. Further research is needed to assess the effect of MT on pain, prosthesis use, and body representation, and to standardize protocols. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Determination of Long Term Motor Control and Cutaneous Sensory Properties of a High Resolution Peripheral Nerve Interface Technology for Limb Amputees

DTIC Science & Technology

2012-12-01

commercial feasibility; involved materials of unknown biocompatibility ; or were low yield in practice. Some approaches required relatively expensive capital...feasibility; involved materials of unknown  biocompatibility  that could not be readily substituted; or were low yield in  practice.  Some of the approaches...possible micro- biocompatibility issues was a tradeoff that had to be made. The following was determined:     1) Use a low molecular weight silicone

Operations manual for the patient assist device. [to handle electrical appliances

NASA Technical Reports Server (NTRS)

Schrader, M. A.

1973-01-01

Quadriplegic patients and multiple amputee patients are almost totally dependent on nursing personnel for any activities or interests in which they participate. A patient assist device is reported which provides patient control over electrical devices in his environment. The patient operates three switches to acquire control over a desired electrical appliance. The type switches employed are chosen to conform to patient capabilities, even when such capabilities are as limited as eye or head movements. The switch operations are sensed and converted into command signals by the patient assist device to control ten electrical appliances simulataneously and independently.

The quest for the bionic arm.

PubMed

Hutchinson, Douglas T

2014-06-01

The current state of research of upper extremity prosthetic devices is focused on creating a complete prosthesis with full motor and sensory function that will provide amputees with a near-normal human arm. Although advances are being made rapidly, many hurdles remain to be overcome before a functional, so-called bionic arm is a reality. Acquiring signals via nerve or muscle inputs will require either a reliable wireless device or direct wiring through an osseous-integrated implant. The best way to tap into the "knowledge" present in the peripheral nerve is yet to be determined. Copyright 2014 by the American Academy of Orthopaedic Surgeons.

The dead spot phenomenon in prosthetic gait: Quantified with an analysis of center of pressure progression and its velocity in the sagittal plane.

PubMed

Klenow, Tyler D; Kahle, Jason T; Highsmith, M Jason

2016-10-01

The "dead spot" phenomenon in prosthetics is a disruption in forward progression observed in the rearfoot of passive prosthetic foot-ankle systems which results in a compensatory and inefficient gait pattern by amputees. A metric to quantify the dead spot as a kinetic event has not yet been introduced. The present study implements a three-part metric to evaluate the dead spot in terms of time, magnitude, and total area using center of pressure velocity and a novel threshold value calculation. The metrics are implemented for proof of efficacy using a convenient sample of four amputees (2 transtibial, 2 transfemoral) who walked in a 3D motion capture system with integrated force plates over five foot conditions. "Continuous-lever" feet designs showed the most favorable metric results between subjects (p<0.05) and in an ad hoc analysis compared to an ideal foot condition within subjects (p>0.05). Ten of 18 (55.6%) foot conditions found to be similar to the ideal were continuous-lever feet. Lack of significant similarity between the feet and ideal conditions (1 of 18, 5.6%) were found in transfemoral subjects. The metric calculations were able to show statistical difference among foot conditions between subjects. One foot (continuous-lever, glass composite) had no detectable dead spot in the transtibial subjects. The lack of significant findings in transfemoral subjects indicates a different coefficient in threshold calculations may be more appropriate for these subjects versus transtibial subjects. Further research with larger sample is needed to determine clinically significant findings among feet and between transtibial and transfemoral subjects. Published by Elsevier Ltd.

Effect of prosthetic alignment changes on socket reaction moment impulse during walking in transtibial amputees.

PubMed

Kobayashi, Toshiki; Orendurff, Michael S; Arabian, Adam K; Rosenbaum-Chou, Teri G; Boone, David A

2014-04-11

The alignment of a lower limb prosthesis affects the way load is transferred to the residual limb through the socket, and this load is critically important for the comfort and function of the prosthesis. Both magnitude and duration of the moment are important factors that may affect the residual limb health. Moment impulse is a well-accepted measurement that incorporates both factors via moment-time integrals. The aim of this study was to investigate the effect of alignment changes on the socket reaction moment impulse in transtibial prostheses. Ten amputees with transtibial prostheses participated in this study. The socket reaction moment impulse was measured at a self-selected walking speed using a Smart Pyramid in 25 alignment conditions, including a nominal alignment (clinically aligned by a prosthetist), as well as angle malalignments of 2°, 4° and 6° (abduction, adduction, extension and flexion) and translation malalignments of 5 mm, 10 mm and 15 mm (lateral, medial, anterior and posterior). The socket reaction moment impulse of the nominal alignment was compared for each condition. The relationship between the alignment and the socket reaction moment impulse was clearly observed in the coronal angle, coronal translation and sagittal translation alignment changes. However, this relationship was not evident in the sagittal angle alignment changes. The results of this study suggested that the socket reaction moment impulse could potentially serve as a valuable parameter to assist the alignment tuning process for transtibial prostheses. Further study is needed to investigate the influence of the socket reaction moment impulse on the residual limb health. Copyright © 2014 Elsevier Ltd. All rights reserved.

Design of a novel prosthetic socket: assessment of the thermal performance.

PubMed

Webber, Christina M; Davis, Brian L

2015-05-01

Prosthetic liners and sockets insulate the residual limb, causing excessive sweating and concomitant skin maceration. When coupled with atypical loading conditions, further dermatologic problems can arise. This can significantly reduce the quality of life of an amputee patient. Improving the design of the prosthetic socket has been proposed as a means of reestablishing a normal thermal environment around the residual limb. In this study, a prosthetic socket was modified by incorporating a helical cooling channel within the socket wall using additive manufacturing techniques. Two sockets were modeled: a control socket, and a modified socket containing a 0.48 cm diameter cooling channel. Computer simulations and bench-top testing were used to assess the design's ability to create a greater temperature differential across the socket wall. A greater temperature drop across the socket wall suggested that the socket could provide cooling benefits to the residual limb by allowing for heat to be drawn away from the limb. The temperature difference across the socket wall was calculated for both sockets in each aspect of the study. Both socket type (p=0.002) and location on the socket (p=0.014) were statistically significant factors affecting the temperature difference between inner and outer socket walls. Compared with the control socket, the modified socket containing a helical cooling channel exhibited greater temperature differences across its wall of 11.1 °C and 6.4 °C in the computer simulations and bench-top testing, respectively. This finding suggested that socket modifications, such as the cooling channel presented, could provide a beneficial cooling effect to an amputee patient's residual limb. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mechanical characterization and validation of poly (methyl methacrylate)/multi walled carbon nanotube composite for the polycentric knee joint.

PubMed

Arun, S; Kanagaraj, S

2015-10-01

Trans femoral amputation is one of the most uncomfortable surgeries in patient׳s life, where the prosthesis consisting of a socket, knee joint, pylon and foot is used to do the walking activities. The artificial prosthetic knee joint imitates the functions of human knee to achieve the flexion-extension for the above knee amputee. The objective of present work is to develop a light weight composite material for the knee joint to reduce the metabolic cost of an amputee. Hence, an attempt was made to study the mechanical properties of multi walled carbon nanotubes (MWCNT) reinforced Poly (methyl methacrylate) (PMMA) prepared through melt mixing technique and optimize the concentration of reinforcement. The PMMA nanocomposites were prepared by reinforcing 0, 0.1, 0.2, 0.25, 0.3 and 0.4 wt% of MWCNT using injection moulding machine via twin screw extruder. It is observed that the tensile and flexural strength of PMMA, which were studied as per ASTM D638 and D790, respectively, were increased by 32.9% and 26.3% till 0.25 wt% reinforcement of MWCNT. The experimental results of strength and modulus were compared with theoretical prediction, where a good correlation was noted. It is concluded that the mechanical properties of PMMA were found to be increased to maximum at 0.25 wt% reinforcement of MWCNT, where the Pukanszky model and modified Halpin-Tsai model are suggested to predict the strength and modulus, respectively, of the PMMA/MWCNT composite, which can be opted as a suitable materiel for the development of polycentric knee joint. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Prosthetic Hand Body Area Controller Based on Efficient Pattern Recognition Control Strategies.

PubMed

Benatti, Simone; Milosevic, Bojan; Farella, Elisabetta; Gruppioni, Emanuele; Benini, Luca

2017-04-15

Poliarticulated prosthetic hands represent a powerful tool to restore functionality and improve quality of life for upper limb amputees. Such devices offer, on the same wearable node, sensing and actuation capabilities, which are not equally supported by natural interaction and control strategies. The control in state-of-the-art solutions is still performed mainly through complex encoding of gestures in bursts of contractions of the residual forearm muscles, resulting in a non-intuitive Human-Machine Interface (HMI). Recent research efforts explore the use of myoelectric gesture recognition for innovative interaction solutions, however there persists a considerable gap between research evaluation and implementation into successful complete systems. In this paper, we present the design of a wearable prosthetic hand controller, based on intuitive gesture recognition and a custom control strategy. The wearable node directly actuates a poliarticulated hand and wirelessly interacts with a personal gateway (i.e., a smartphone) for the training and personalization of the recognition algorithm. Through the whole system development, we address the challenge of integrating an efficient embedded gesture classifier with a control strategy tailored for an intuitive interaction between the user and the prosthesis. We demonstrate that this combined approach outperforms systems based on mere pattern recognition, since they target the accuracy of a classification algorithm rather than the control of a gesture. The system was fully implemented, tested on healthy and amputee subjects and compared against benchmark repositories. The proposed approach achieves an error rate of 1.6% in the end-to-end real time control of commonly used hand gestures, while complying with the power and performance budget of a low-cost microcontroller.

One-Channel Surface Electromyography Decomposition for Muscle Force Estimation.

PubMed

Sun, Wentao; Zhu, Jinying; Jiang, Yinlai; Yokoi, Hiroshi; Huang, Qiang

2018-01-01

Estimating muscle force by surface electromyography (sEMG) is a non-invasive and flexible way to diagnose biomechanical diseases and control assistive devices such as prosthetic hands. To estimate muscle force using sEMG, a supervised method is commonly adopted. This requires simultaneous recording of sEMG signals and muscle force measured by additional devices to tune the variables involved. However, recording the muscle force of the lost limb of an amputee is challenging, and the supervised method has limitations in this regard. Although the unsupervised method does not require muscle force recording, it suffers from low accuracy due to a lack of reference data. To achieve accurate and easy estimation of muscle force by the unsupervised method, we propose a decomposition of one-channel sEMG signals into constituent motor unit action potentials (MUAPs) in two steps: (1) learning an orthogonal basis of sEMG signals through reconstruction independent component analysis; (2) extracting spike-like MUAPs from the basis vectors. Nine healthy subjects were recruited to evaluate the accuracy of the proposed approach in estimating muscle force of the biceps brachii. The results demonstrated that the proposed approach based on decomposed MUAPs explains more than 80% of the muscle force variability recorded at an arbitrary force level, while the conventional amplitude-based approach explains only 62.3% of this variability. With the proposed approach, we were also able to achieve grip force control of a prosthetic hand, which is one of the most important clinical applications of the unsupervised method. Experiments on two trans-radial amputees indicated that the proposed approach improves the performance of the prosthetic hand in grasping everyday objects.

Model-based Bayesian signal extraction algorithm for peripheral nerves

NASA Astrophysics Data System (ADS)

Eggers, Thomas E.; Dweiri, Yazan M.; McCallum, Grant A.; Durand, Dominique M.

2017-10-01

Objective. Multi-channel cuff electrodes have recently been investigated for extracting fascicular-level motor commands from mixed neural recordings. Such signals could provide volitional, intuitive control over a robotic prosthesis for amputee patients. Recent work has demonstrated success in extracting these signals in acute and chronic preparations using spatial filtering techniques. These extracted signals, however, had low signal-to-noise ratios and thus limited their utility to binary classification. In this work a new algorithm is proposed which combines previous source localization approaches to create a model based method which operates in real time. Approach. To validate this algorithm, a saline benchtop setup was created to allow the precise placement of artificial sources within a cuff and interference sources outside the cuff. The artificial source was taken from five seconds of chronic neural activity to replicate realistic recordings. The proposed algorithm, hybrid Bayesian signal extraction (HBSE), is then compared to previous algorithms, beamforming and a Bayesian spatial filtering method, on this test data. An example chronic neural recording is also analyzed with all three algorithms. Main results. The proposed algorithm improved the signal to noise and signal to interference ratio of extracted test signals two to three fold, as well as increased the correlation coefficient between the original and recovered signals by 10-20%. These improvements translated to the chronic recording example and increased the calculated bit rate between the recovered signals and the recorded motor activity. Significance. HBSE significantly outperforms previous algorithms in extracting realistic neural signals, even in the presence of external noise sources. These results demonstrate the feasibility of extracting dynamic motor signals from a multi-fascicled intact nerve trunk, which in turn could extract motor command signals from an amputee for the end goal of controlling a prosthetic limb.

Psychometric properties of the Activities-specific Balance Confidence Scale among individuals with a lower-limb amputation.

PubMed

Miller, William C; Deathe, A Barry; Speechley, Mark

2003-05-01

To evaluate the internal consistency, test-retest reliability, and construct validity of the Activities-specific Balance Confidence (ABC) Scale among people who have a lower-limb amputation. Retest design. A university-affiliated outpatient amputee clinic in Ontario. Two samples of individuals who have unilateral transtibial and transfemoral amputation. Sample 1 (n=54) was a consecutive and sample 2 (n=329) a convenience sample of all members of the clinic population. Not applicable. Repeated application of the ABC Scale, a 16-item questionnaire that assesses confidence in performing various mobility-related tasks. Correlation to test hypothesized relationships between the ABC Scale and the 2-minute walk (2MWT) and the timed up-and-go (TUG) tests; and assessment of the ability of the ABC Scale to discriminate among groups based on amputation cause, amputation level, mobility device use, automatic stepping ability, wearing time, stair climbing ability, and walking distance. Test-retest reliability (intraclass correlation coefficient) of the ABC Scale was .91 (95% confidence interval [CI], .84-.95) with individual item test-retest coefficients ranging from .53 to .87. Internal consistency, measured by Cronbach alpha, was .95. Hypothesized associations with the 2MWT and TUG test were observed with correlations of .72 (95% CI, .56-.84) and -.70 (95% CI, -.82 to -.53), respectively. The ABC Scale discriminated between all groups except those based on amputation level. Balance confidence, as measured by the ABC Scale, is a construct that provides unique information potentially useful to clinicians who provide amputee rehabilitation. The ABC Scale is reliable, with strong support for validity. Study of the scale's responsiveness is recommended.

Beam walking can detect differences in walking balance proficiency across a range of sensorimotor abilities.

PubMed

Sawers, Andrew; Ting, Lena H

2015-02-01

The ability to quantify differences in walking balance proficiency is critical to curbing the rising health and financial costs of falls. Current laboratory-based approaches typically focus on successful recovery of balance while clinical instruments often pose little difficulty for all but the most impaired patients. Rarely do they test motor behaviors of sufficient difficulty to evoke failures in balance control limiting their ability to quantify balance proficiency. Our objective was to test whether a simple beam-walking task could quantify differences in walking balance proficiency across a range of sensorimotor abilities. Ten experts, ten novices, and five individuals with transtibial limb loss performed six walking trials across three different width beams. Walking balance proficiency was quantified as the ratio of distance walked to total possible distance. Balance proficiency was not significantly different between cohorts on the wide-beam, but clear differences between cohorts on the mid and narrow-beams were identified. Experts walked a greater distance than novices on the mid-beam (average of 3.63±0.04m verus 2.70±0.21m out of 3.66m; p=0.009), and novices walked further than amputees (1.52±0.20m; p=0.03). Amputees were unable to walk on the narrow-beam, while experts walked further (3.07±0.14m) than novices (1.55±0.26m; p=0.0005). A simple beam-walking task and an easily collected measure of distance traveled detected differences in walking balance proficiency across sensorimotor abilities. This approach provides a means to safely study and evaluate successes and failures in walking balance in the clinic or lab. It may prove useful in identifying mechanisms underlying falls versus fall recoveries. Copyright © 2015 Elsevier B.V. All rights reserved.

Microstimulation of the lumbar DRG recruits primary afferent neurons in localized regions of lower limb.

PubMed

Ayers, Christopher A; Fisher, Lee E; Gaunt, Robert A; Weber, Douglas J

2016-07-01

Patterned microstimulation of the dorsal root ganglion (DRG) has been proposed as a method for delivering tactile and proprioceptive feedback to amputees. Previous studies demonstrated that large- and medium-diameter afferent neurons could be recruited separately, even several months after implantation. However, those studies did not examine the anatomical localization of sensory fibers recruited by microstimulation in the DRG. Achieving precise recruitment with respect to both modality and receptive field locations will likely be crucial to create a viable sensory neuroprosthesis. In this study, penetrating microelectrode arrays were implanted in the L5, L6, and L7 DRG of four isoflurane-anesthetized cats instrumented with nerve cuff electrodes around the proximal and distal branches of the sciatic and femoral nerves. A binary search was used to find the recruitment threshold for evoking a response in each nerve cuff. The selectivity of DRG stimulation was characterized by the ability to recruit individual distal branches to the exclusion of all others at threshold; 84.7% (n = 201) of the stimulation electrodes recruited a single nerve branch, with 9 of the 15 instrumented nerves recruited selectively. The median stimulation threshold was 0.68 nC/phase, and the median dynamic range (increase in charge while stimulation remained selective) was 0.36 nC/phase. These results demonstrate the ability of DRG microstimulation to achieve selective recruitment of the major nerve branches of the hindlimb, suggesting that this approach could be used to drive sensory input from localized regions of the limb. This sensory input might be useful for restoring tactile and proprioceptive feedback to a lower-limb amputee. Copyright © 2016 the American Physiological Society.

Clinically Relevant Outcome Measures Following Limb Osseointegration; Systematic Review of the Literature.

PubMed

Al Muderis, Munjed M; Lu, William Y; Li, Jiao Jiao; Kaufman, Kenton; Orendurff, Michael; Highsmith, M Jason; Lunseth, Paul A; Kahle, Jason T

2018-02-01

The current standard of care for an amputee is a socket-based prostheses. An osseointegrated implant (OI) is an alternative for prosthetic attachment. Osseointegration addresses reported problems related to wearing a socket interface, such as skin issues, discomfort, diminished function, quality of life, prosthetic use, and abandonment. The purpose of this report is to systematically review current literature regarding OI to identify and categorize the reported clinically relevant outcome measures, rate the quality of available evidence, and synthesize the findings. A multidisciplinary team used PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methods. Search methodology was based on identifying clinically relevant articles. Three databases were searched: PubMed, CINAHL, and Web of Science. Clinical studies with aggregated data reporting at least 1 clinically relevant outcome measure were included. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criterion was used for critical appraisal and recommendations. This review identified 21 clinically relevant observational studies. Outcome measures were categorized into the following 9 categories: vibratory stimulation, complications, biomechanics, economics, patient-reported outcome measures, electromyography, x-ray, physical functional performance, and energy consumption. This systematic review consisted of Level III and IV observational studies. Homogeneous outcome measures with strong psychometric properties across prospective studies do not exist to date. Higher-level, prospective, randomized, long-term, clinically relevant trials are needed to prove efficacy of OI compared with socket prosthetic attachment. Osseointegration was at least equivalent to sockets in most studies. In some cases, it was superior. Osseointegration represents a promising alternative to socket prosthetic attachments for extremity amputees. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Combined analysis of cortical (EEG) and nerve stump signals improves robotic hand control.

PubMed

Tombini, Mario; Rigosa, Jacopo; Zappasodi, Filippo; Porcaro, Camillo; Citi, Luca; Carpaneto, Jacopo; Rossini, Paolo Maria; Micera, Silvestro

2012-01-01

Interfacing an amputee's upper-extremity stump nerves to control a robotic hand requires training of the individual and algorithms to process interactions between cortical and peripheral signals. To evaluate for the first time whether EEG-driven analysis of peripheral neural signals as an amputee practices could improve the classification of motor commands. Four thin-film longitudinal intrafascicular electrodes (tf-LIFEs-4) were implanted in the median and ulnar nerves of the stump in the distal upper arm for 4 weeks. Artificial intelligence classifiers were implemented to analyze LIFE signals recorded while the participant tried to perform 3 different hand and finger movements as pictures representing these tasks were randomly presented on a screen. In the final week, the participant was trained to perform the same movements with a robotic hand prosthesis through modulation of tf-LIFE-4 signals. To improve the classification performance, an event-related desynchronization/synchronization (ERD/ERS) procedure was applied to EEG data to identify the exact timing of each motor command. Real-time control of neural (motor) output was achieved by the participant. By focusing electroneurographic (ENG) signal analysis in an EEG-driven time window, movement classification performance improved. After training, the participant regained normal modulation of background rhythms for movement preparation (α/β band desynchronization) in the sensorimotor area contralateral to the missing limb. Moreover, coherence analysis found a restored α band synchronization of Rolandic area with frontal and parietal ipsilateral regions, similar to that observed in the opposite hemisphere for movement of the intact hand. Of note, phantom limb pain (PLP) resolved for several months. Combining information from both cortical (EEG) and stump nerve (ENG) signals improved the classification performance compared with tf-LIFE signals processing alone; training led to cortical reorganization and mitigation of PLP.

Sensor fusion and computer vision for context-aware control of a multi degree-of-freedom prosthesis

NASA Astrophysics Data System (ADS)

Markovic, Marko; Dosen, Strahinja; Popovic, Dejan; Graimann, Bernhard; Farina, Dario

2015-12-01

Objective. Myoelectric activity volitionally generated by the user is often used for controlling hand prostheses in order to replicate the synergistic actions of muscles in healthy humans during grasping. Muscle synergies in healthy humans are based on the integration of visual perception, heuristics and proprioception. Here, we demonstrate how sensor fusion that combines artificial vision and proprioceptive information with the high-level processing characteristics of biological systems can be effectively used in transradial prosthesis control. Approach. We developed a novel context- and user-aware prosthesis (CASP) controller integrating computer vision and inertial sensing with myoelectric activity in order to achieve semi-autonomous and reactive control of a prosthetic hand. The presented method semi-automatically provides simultaneous and proportional control of multiple degrees-of-freedom (DOFs), thus decreasing overall physical effort while retaining full user control. The system was compared against the major commercial state-of-the art myoelectric control system in ten able-bodied and one amputee subject. All subjects used transradial prosthesis with an active wrist to grasp objects typically associated with activities of daily living. Main results. The CASP significantly outperformed the myoelectric interface when controlling all of the prosthesis DOF. However, when tested with less complex prosthetic system (smaller number of DOF), the CASP was slower but resulted with reaching motions that contained less compensatory movements. Another important finding is that the CASP system required minimal user adaptation and training. Significance. The CASP constitutes a substantial improvement for the control of multi-DOF prostheses. The application of the CASP will have a significant impact when translated to real-life scenarious, particularly with respect to improving the usability and acceptance of highly complex systems (e.g., full prosthetic arms) by amputees.

Regenerative Engineering and Bionic Limbs.

PubMed

James, Roshan; Laurencin, Cato T

2015-03-01

Amputations of the upper extremity are severely debilitating, current treatments support very basic limb movement, and patients undergo extensive physiotherapy and psychological counselling. There is no prosthesis that allows the amputees near-normal function. With increasing number of amputees due to injuries sustained in accidents, natural calamities and international conflicts, there is a growing requirement for novel strategies and new discoveries. Advances have been made in technological, material and in prosthesis integration where researchers are now exploring artificial prosthesis that integrate with the residual tissues and function based on signal impulses received from the residual nerves. Efforts are focused on challenging experts in different disciplines to integrate ideas and technologies to allow for the regeneration of injured tissues, recording on tissue signals and feed-back to facilitate responsive movements and gradations of muscle force. A fully functional replacement and regenerative or integrated prosthesis will rely on interface of biological process with robotic systems to allow individual control of movement such as at the elbow, forearm, digits and thumb in the upper extremity. Regenerative engineering focused on the regeneration of complex tissue and organ systems will be realized by the cross-fertilization of advances over the past thirty years in the fields of tissue engineering, nanotechnology, stem cell science, and developmental biology. The convergence of toolboxes crated within each discipline will allow interdisciplinary teams from engineering, science, and medicine to realize new strategies, mergers of disparate technologies, such as biophysics, smart bionics, and the healing power of the mind. Tackling the clinical challenges, interfacing the biological process with bionic technologies, engineering biological control of the electronic systems, and feed-back will be the important goals in regenerative engineering over the next two decades.

Deep Learning with Convolutional Neural Networks Applied to Electromyography Data: A Resource for the Classification of Movements for Prosthetic Hands

PubMed Central

Atzori, Manfredo; Cognolato, Matteo; Müller, Henning

2016-01-01

Natural control methods based on surface electromyography (sEMG) and pattern recognition are promising for hand prosthetics. However, the control robustness offered by scientific research is still not sufficient for many real life applications, and commercial prostheses are capable of offering natural control for only a few movements. In recent years deep learning revolutionized several fields of machine learning, including computer vision and speech recognition. Our objective is to test its methods for natural control of robotic hands via sEMG using a large number of intact subjects and amputees. We tested convolutional networks for the classification of an average of 50 hand movements in 67 intact subjects and 11 transradial amputees. The simple architecture of the neural network allowed to make several tests in order to evaluate the effect of pre-processing, layer architecture, data augmentation and optimization. The classification results are compared with a set of classical classification methods applied on the same datasets. The classification accuracy obtained with convolutional neural networks using the proposed architecture is higher than the average results obtained with the classical classification methods, but lower than the results obtained with the best reference methods in our tests. The results show that convolutional neural networks with a very simple architecture can produce accurate results comparable to the average classical classification methods. They show that several factors (including pre-processing, the architecture of the net and the optimization parameters) can be fundamental for the analysis of sEMG data. Larger networks can achieve higher accuracy on computer vision and object recognition tasks. This fact suggests that it may be interesting to evaluate if larger networks can increase sEMG classification accuracy too. PMID:27656140

Comparison of mobility and user satisfaction between a microprocessor knee and a standard prosthetic knee: a summary of seven single-subject trials.

PubMed

Howard, Charla L; Wallace, Chris; Perry, Bonnie; Stokic, Dobrivoje S

2018-03-01

Insufficient evidence of the benefits provided by costlier microprocessor knees (MPKs) over nonmicroprocessor knees (NMPKs) often causes concern when considering MPK prescription. Thus, more studies are needed to demonstrate differences between MPKs and NMPKs and define sensitive outcomes to guide MPK prescription. The aim of this study was to evaluate the impact of switching from NMPK to MPK on measures of mobility and preference. Seven long-term NMPK users (all men, ages 50-84, 3-64 years postamputation) participated in this study, which use a single-subject design (ABA or BAB; A=NMPK, B=MPK). Mobility was assessed with the Amputee Mobility Predictor, Berg Balance Scale (BBS), L-Test, 6-Min Walk Test (6MWT) with Physiological Cost Index, and self-selected normal and very fast gait speeds. The preference between NMPK and MPK was evaluated by the Prosthesis Evaluation Questionnaire (PEQ) and the visual analog scale. Mobility improved with the MPK in six of seven participants, which was most often captured with BBS (median: +6 points) and 6MWT (median: +63 m). These improvements typically exceeded minimal clinically important difference or minimal detectable change thresholds. Most participants scored the MPK higher on the PEQ (median: +20 points) and six of seven expressed a global preference toward MPK. In the BAB group, the Amputee Mobility Predictor and BBS correlated with perception of change on several PEQ domains (Ρ≥0.59). In conclusion, MPKs may provide better outcomes and user satisfaction, particularly in those with lower mobility function. BBS and 6MWT were found to be the most sensitive measures to capture changes in mobility while using MPK for several weeks.

Differences in knee flexion between the Genium and C-Leg microprocessor knees while walking on level ground and ramps.

PubMed

Lura, Derek J; Wernke, Matthew M; Carey, Stephanie L; Kahle, Jason T; Miro, Rebecca M; Highsmith, M Jason

2015-02-01

Microprocessor knees have improved the gait and functional abilities of persons with transfemoral amputation. The Genium prosthetic knee offers an advanced sensor and control system designed to decrease impairment by: allowing greater stance phase flexion, easing transitions between gait phases, and compensating for changes in terrain. The aim of this study was to determine differences between the knee flexion angle of persons using the Genium knee, the C-Leg knee, and non-amputee controls; and to evaluate the impact the prostheses on gait and level of impairment of the user. This study used a randomized experimental crossover of persons with transfemoral amputation using the Genium and C-Leg microprocessor knees (n=25), with an observational sample of non-amputee controls (n=5). Gait analysis by 3D motion tracking of subjects ambulating at different speeds on level ground and on 5° and 10° ramps was completed. Use of the Genium resulted in a significant increase in peak knee flexion for swing (5°, p<0.01, d=0.34) and stance (2°, p<0.01, d=0.19) phases relative to C-Leg use. There was a high degree of variability between subjects, and significant differences still remain between the Genium group and the control group's knee flexion angles for most speeds and slopes. The Genium knee generally increases flexion in swing and stance, potentially decreasing the level of impairment for persons with transfemoral amputation. This study demonstrates functional differences between the C-Leg and Genium knees to help prosthetists determine if the Genium will provide functional benefits to individual patients. Copyright © 2014 Elsevier Ltd. All rights reserved.

The quality of life analysis of knee prosthesis with complete microprocessor control in trans-femoral amputees.

PubMed

Saglam, Yavuz; Gulenc, Baris; Birisik, Fevzi; Ersen, Ali; Yilmaz Yalcinkaya, Ebru; Yazicioglu, Onder

2017-12-01

The aim of this study was to analyze the patient demographics, etiology of limb loss as well as reporting SF-36 scores for microprocessor prosthesis users in Turkish population. We reviewed 72 patients (61 male and 11 female; mean age: 37.7 ± 10.7) with uni-lateral, above knee amputation and a history of regular and microprocessor prosthesis use. All patients were called back for a last follow-up and they were asked to fill a self-administered general health status questionnaire (SF-36). According to the SF-36 results; physical component score (PCS) score was 46 ± 7.3 and mental components summary (MCS) score was 46.5 ± 9.1. These scores have statistical similarity with Turkish healthy controls, except SF (social functioning) sub-dimension. PCS score for women microprocessor users were significantly lower than men (43.3 vs. 48.7, p = 0.03), but MCS scores were similar in between genders (46 vs. 48.2, p = 0.13). Conventional prostheses usage time was positively correlated with physical function (PF) scores (r = 0.322, p = 0.010). Microprocessor prosthesis usage time was negatively correlated with role limitations due to emotional problem (RE) scores (r = -0,313, p = 0.009). The quality of life surveys were showed that the loss of an extremity have higher physical and psychological impact on women's physical scores. Overall, SF-36 results were similar in microprocessor using amputee's and Turkish normal controls. Level IV, therapeutic study. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

Deep Learning with Convolutional Neural Networks Applied to Electromyography Data: A Resource for the Classification of Movements for Prosthetic Hands.

PubMed

Atzori, Manfredo; Cognolato, Matteo; Müller, Henning

2016-01-01

Natural control methods based on surface electromyography (sEMG) and pattern recognition are promising for hand prosthetics. However, the control robustness offered by scientific research is still not sufficient for many real life applications, and commercial prostheses are capable of offering natural control for only a few movements. In recent years deep learning revolutionized several fields of machine learning, including computer vision and speech recognition. Our objective is to test its methods for natural control of robotic hands via sEMG using a large number of intact subjects and amputees. We tested convolutional networks for the classification of an average of 50 hand movements in 67 intact subjects and 11 transradial amputees. The simple architecture of the neural network allowed to make several tests in order to evaluate the effect of pre-processing, layer architecture, data augmentation and optimization. The classification results are compared with a set of classical classification methods applied on the same datasets. The classification accuracy obtained with convolutional neural networks using the proposed architecture is higher than the average results obtained with the classical classification methods, but lower than the results obtained with the best reference methods in our tests. The results show that convolutional neural networks with a very simple architecture can produce accurate results comparable to the average classical classification methods. They show that several factors (including pre-processing, the architecture of the net and the optimization parameters) can be fundamental for the analysis of sEMG data. Larger networks can achieve higher accuracy on computer vision and object recognition tasks. This fact suggests that it may be interesting to evaluate if larger networks can increase sEMG classification accuracy too.

A Prosthetic Hand Body Area Controller Based on Efficient Pattern Recognition Control Strategies

PubMed Central

Benatti, Simone; Milosevic, Bojan; Farella, Elisabetta; Gruppioni, Emanuele; Benini, Luca

2017-01-01

Poliarticulated prosthetic hands represent a powerful tool to restore functionality and improve quality of life for upper limb amputees. Such devices offer, on the same wearable node, sensing and actuation capabilities, which are not equally supported by natural interaction and control strategies. The control in state-of-the-art solutions is still performed mainly through complex encoding of gestures in bursts of contractions of the residual forearm muscles, resulting in a non-intuitive Human-Machine Interface (HMI). Recent research efforts explore the use of myoelectric gesture recognition for innovative interaction solutions, however there persists a considerable gap between research evaluation and implementation into successful complete systems. In this paper, we present the design of a wearable prosthetic hand controller, based on intuitive gesture recognition and a custom control strategy. The wearable node directly actuates a poliarticulated hand and wirelessly interacts with a personal gateway (i.e., a smartphone) for the training and personalization of the recognition algorithm. Through the whole system development, we address the challenge of integrating an efficient embedded gesture classifier with a control strategy tailored for an intuitive interaction between the user and the prosthesis. We demonstrate that this combined approach outperforms systems based on mere pattern recognition, since they target the accuracy of a classification algorithm rather than the control of a gesture. The system was fully implemented, tested on healthy and amputee subjects and compared against benchmark repositories. The proposed approach achieves an error rate of 1.6% in the end-to-end real time control of commonly used hand gestures, while complying with the power and performance budget of a low-cost microcontroller. PMID:28420135

A descriptive study of traumatic lower limb amputees from the Hospital Hel Trabajador: clinical evolution from the accident until rehabilitation discharge.

PubMed

Rotter, Karin; Sanhueza, Roberto; Robles, Karina; Godoy, Marcela

2006-04-01

The purpose of the study was to describe the demographics, the causes of amputations, the amputation levels, the clinical outcomes, the durability of prostheses in unilateral lower limb amputee among workers entitled to non-state related work insurance, the ACHS, Chile, between 1974 and 2001. It was a retrospective descriptive study based on selected clinical files. One hundred files, with the minimal data required, were selected with a diagnosis of traumatic lower limb amputation, the levels ranging from Boyd's foot amputation to hip disarticulation, as defined by the Occupational Accidents Act from 1974 to December 2001. The mean age was 35.5 years, 96% were males, with an average follow-up of 7.7 years. In 50% of the cases the education level did not exceed elementary school. Ninety-eight percent were blue collar workers. The traumatic injury resulting in amputation took place during work in 89% of the cases the main causes being crushing injury (50%), traffic accident (19%), run over by car (14%) and burns (6%). The most common amputation levels were trans-femoral (40%) and trans-tibial (47%). Amputations were performed within the first 24 h in 49% of the cases. The hospitalization stay reached 8 weeks in 56.7%. Early complications were dehiscence (9.4%), superficial infection, (14.6%) and deep infection (26%). Late complications detected were soft tissue lesions (34.1%), exostosis (3.6%), painful neuroma (12.5%) and phantom limb pain (12.5%). Prostheses durability was on average 3 years. The average period to resume work was 1 year for 60% of the cases.

Dynamic Time Warping compared to established methods for validation of musculoskeletal models.

PubMed

Gaspar, Martin; Welke, Bastian; Seehaus, Frank; Hurschler, Christof; Schwarze, Michael

2017-04-11

By means of Multi-Body musculoskeletal simulation, important variables such as internal joint forces and moments can be estimated which cannot be measured directly. Validation can ensued by qualitative or by quantitative methods. Especially when comparing time-dependent signals, many methods do not perform well and validation is often limited to qualitative approaches. The aim of the present study was to investigate the capabilities of the Dynamic Time Warping (DTW) algorithm for comparing time series, which can quantify phase as well as amplitude errors. We contrast the sensitivity of DTW with other established metrics: the Pearson correlation coefficient, cross-correlation, the metric according to Geers, RMSE and normalized RMSE. This study is based on two data sets, where one data set represents direct validation and the other represents indirect validation. Direct validation was performed in the context of clinical gait-analysis on trans-femoral amputees fitted with a 6 component force-moment sensor. Measured forces and moments from amputees' socket-prosthesis are compared to simulated forces and moments. Indirect validation was performed in the context of surface EMG measurements on a cohort of healthy subjects with measurements taken of seven muscles of the leg, which were compared to simulated muscle activations. Regarding direct validation, a positive linear relation between results of RMSE and nRMSE to DTW can be seen. For indirect validation, a negative linear relation exists between Pearson correlation and cross-correlation. We propose the DTW algorithm for use in both direct and indirect quantitative validation as it correlates well with methods that are most suitable for one of the tasks. However, in DV it should be used together with methods resulting in a dimensional error value, in order to be able to interpret results more comprehensible. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effectiveness of the bone bridge transtibial amputation technique: A systematic review of high-quality evidence.

PubMed

Kahle, Jason T; Highsmith, M Jason; Kenney, John; Ruth, Tim; Lunseth, Paul A; Ertl, Janos

2017-06-01

This literature review was undertaken to determine if commonly held views about the benefits of a bone bridge technique are supported by the literature. Four databases were searched for articles pertaining to surgical strategies specific to a bone bridge technique of the transtibial amputee. A total of 35 articles were identified as potential articles. Authors included methodology that was applied to separate topics. Following identification, articles were excluded if they were determined to be low quality evidence or not pertinent. Nine articles were identified to be pertinent to one of the topics: Perioperative Care, Acute Care, Subjective Analysis and Function. Two articles sorted into multiple topics. Two articles were sorted into the Perioperative Care topic, 4 articles sorted into the Acute Care topic, 2 articles into the Subjective Analysis topic and 5 articles into the Function topic. There are no high quality (level one or two) clinical trials reporting comparisons of the bone bridge technique to traditional methods. There is limited evidence supporting the clinical outcomes of the bone bridge technique. There is no agreement supporting or discouraging the perioperative and acute care aspects of the bone bridge technique. There is no evidence defining an interventional comparison of the bone bridge technique. Current level III evidence supports a bone bridge technique as an equivalent option to the non-bone bridge transtibial amputation technique. Formal level I and II clinical trials will need to be considered in the future to guide clinical practice. Clinical relevance Clinical Practice Guidelines are evidence based. This systematic literature review identifies the highest quality evidence to date which reports a consensus of outcomes agreeing bone bridge is as safe and effective as alternatives. The clinical relevance is understanding bone bridge could additionally provide a mechanistic advantage for the transtibial amputee.

Regenerative Engineering and Bionic Limbs

PubMed Central

James, Roshan; Laurencin, Cato T.

2015-01-01

Amputations of the upper extremity are severely debilitating, current treatments support very basic limb movement, and patients undergo extensive physiotherapy and psychological counselling. There is no prosthesis that allows the amputees near-normal function. With increasing number of amputees due to injuries sustained in accidents, natural calamities and international conflicts, there is a growing requirement for novel strategies and new discoveries. Advances have been made in technological, material and in prosthesis integration where researchers are now exploring artificial prosthesis that integrate with the residual tissues and function based on signal impulses received from the residual nerves. Efforts are focused on challenging experts in different disciplines to integrate ideas and technologies to allow for the regeneration of injured tissues, recording on tissue signals and feed-back to facilitate responsive movements and gradations of muscle force. A fully functional replacement and regenerative or integrated prosthesis will rely on interface of biological process with robotic systems to allow individual control of movement such as at the elbow, forearm, digits and thumb in the upper extremity. Regenerative engineering focused on the regeneration of complex tissue and organ systems will be realized by the cross-fertilization of advances over the past thirty years in the fields of tissue engineering, nanotechnology, stem cell science, and developmental biology. The convergence of toolboxes crated within each discipline will allow interdisciplinary teams from engineering, science, and medicine to realize new strategies, mergers of disparate technologies, such as biophysics, smart bionics, and the healing power of the mind. Tackling the clinical challenges, interfacing the biological process with bionic technologies, engineering biological control of the electronic systems, and feed-back will be the important goals in regenerative engineering over the next two decades. PMID:25983525

Sensor fusion and computer vision for context-aware control of a multi degree-of-freedom prosthesis.

PubMed

Markovic, Marko; Dosen, Strahinja; Popovic, Dejan; Graimann, Bernhard; Farina, Dario

2015-12-01

Myoelectric activity volitionally generated by the user is often used for controlling hand prostheses in order to replicate the synergistic actions of muscles in healthy humans during grasping. Muscle synergies in healthy humans are based on the integration of visual perception, heuristics and proprioception. Here, we demonstrate how sensor fusion that combines artificial vision and proprioceptive information with the high-level processing characteristics of biological systems can be effectively used in transradial prosthesis control. We developed a novel context- and user-aware prosthesis (CASP) controller integrating computer vision and inertial sensing with myoelectric activity in order to achieve semi-autonomous and reactive control of a prosthetic hand. The presented method semi-automatically provides simultaneous and proportional control of multiple degrees-of-freedom (DOFs), thus decreasing overall physical effort while retaining full user control. The system was compared against the major commercial state-of-the art myoelectric control system in ten able-bodied and one amputee subject. All subjects used transradial prosthesis with an active wrist to grasp objects typically associated with activities of daily living. The CASP significantly outperformed the myoelectric interface when controlling all of the prosthesis DOF. However, when tested with less complex prosthetic system (smaller number of DOF), the CASP was slower but resulted with reaching motions that contained less compensatory movements. Another important finding is that the CASP system required minimal user adaptation and training. The CASP constitutes a substantial improvement for the control of multi-DOF prostheses. The application of the CASP will have a significant impact when translated to real-life scenarious, particularly with respect to improving the usability and acceptance of highly complex systems (e.g., full prosthetic arms) by amputees.

Ethical, financial, and policy considerations in hand transplantation.

PubMed

Chang, Jeff; Mathes, David W

2011-11-01

Currently, more than 65 hand transplants have been performed with studies demonstrating favorable cosmetic and functional outcomes and cortical reintegration of the transplanted hand. Due to such favorable outcomes, many view hand transplant as a potential gold standard for treatment of a double amputee. However, ethical debate continues regarding risks and benefits of this nonlifesaving procedure. Clinicians, patients, and society must agree on whether hand transplantation is ethical and affordable. If a decision is made to transplant a hand, this must be performed in a dedicated center that facilitates integration of multiple specialists, ethicists, pharmacists, and rehabilitationists. Copyright © 2011 Elsevier Inc. All rights reserved.

Disappearance of "phantom limb" and amputated arm usage during dreaming in REM sleep behaviour disorder.

PubMed

Vetrugno, Roberto; Arnulf, Isabelle; Montagna, Pasquale

2009-01-01

Limb amputation is followed, in approximately 90% of patients, by "phantom limb" sensations during wakefulness. When amputated patients dream, however, the phantom limb may be present all the time, part of the time, intermittently or not at all. Such dreaming experiences in amputees have usually been obtained only retrospectively in the morning and, moreover, dreaming is normally associated with muscular atonia so the motor counterpart of the phantom limb experience cannot be observed directly. REM sleep behaviour disorder (RBD), in which muscle atonia is absent during REM sleep and patients act out their dreams, allows a more direct analysis of the "phantom limb" phenomena and their modifications during sleep.

Metabolic cost of level-ground walking with a robotic transtibial prosthesis combining push-off power and nonlinear damping behaviors: preliminary results.

PubMed

Yanggang Feng; Jinying Zhu; Qining Wang

2016-08-01

Recent advances in robotic technology are facilitating the development of robotic prostheses. Our previous studies proposed a lightweight robotic transtibial prosthesis with a damping control strategy. To improve the performance of power assistance, in this paper, we redesign the prosthesis and improve the control strategy by supplying extra push-off power. A male transtibial amputee subject volunteered to participate in the study. Preliminary experimental results show that the proposed prosthesis with push-off control improves energy expenditure by a percentage ranged from 9.72 % to 14.99 % for level-ground walking compared with the one using non-push-off control.

An extremely lightweight fingernail worn prosthetic interface device

NASA Astrophysics Data System (ADS)

Yetkin, Oguz; Ahluwalia, Simranjit; Silva, Dinithi; Kasi-Okonye, Isioma; Volker, Rachael; Baptist, Joshua R.; Popa, Dan O.

2016-05-01

Upper limb prosthetics are currently operated using several electromyography sensors mounted on an amputee's residual limb. In order for any prosthetic driving interface to be widely adopted, it needs to be responsive, lightweight, and out of the way when not being used. In this paper we discuss the possibility of replacing such electrodes with fingernail optical sensor systems mounted on the sound limb. We present a prototype device that can detect pinch gestures and communicate with the prosthetic system. The device detects the relative position of fingers to each other by measuring light transmitted via tissue. Applications are not limited to prosthetic control, but can be extended to other human-machine interfaces.

William Porterfield (ca. 1696-1771) and his phantom limb: an overlooked first self-report by a man of medicine.

PubMed

Wade, Nicholas J; Finger, Stanley

2003-05-01

EARLY REPORTS OF phantom limbs by Ambroise Paré and René Descartes were based on second- or third-hand descriptions provided by amputees. William Porterfield (ca. 1696-1771) was a prominent Scottish physician and was possibly the first man of medicine to write about his experiences after having a leg amputated. Porterfield was an authority on vision; he devised the first optometer and examined accommodation after cataract operations. Rather than using the phenomenon of a phantom limb to question the veracity of the senses (as Descartes had done), Porterfield integrated his phantom limb experiences into his general account of sensory function.

Advances in upper extremity prosthetics.

PubMed

Zlotolow, Dan A; Kozin, Scott H

2012-11-01

Until recently, upper extremity prostheses had changed little since World War II. In 2006, the Defense Advanced Research Projects Agency responded to an increasing number of military amputees with the Revolutionizing Prosthetics program. The program has yielded several breakthroughs both in the engineering of new prosthetic arms and in the control of those arms. Direct brain-wave control of a limb with 22° of freedom may be within reach. In the meantime, advances such as individually powered digits have opened the door to multifunctional full and partial hand prostheses. Restoring sensation to the prosthetic limb remains a major challenge to full integration of the limb into a patient's self-image. Copyright © 2012 Elsevier Inc. All rights reserved.

Silicone Molding and Lifetime Testing of Peripheral Nerve Interfaces for Neuroprostheses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gupte, Kimaya; Tolosa, Vanessa

Implantable peripheral nerve cuffs have a large application in neuroprostheses as they can be used to restore sensation to those with upper limb amputations. Modern day prosthetics, while lessening the pain associated with phantom limb syndrome, have limited fine motor control and do not provide sensory feedback to patients. Sensory feedback with prosthetics requires communication between the nervous system and limbs, and is still a challenge to accomplish with amputees. Establishing this communication between the peripheral nerves in the arm and artificial limbs is vital as prosthetics research aims to provide sensory feedback to amputees. Peripheral nerve cuffs restore sensationmore » by electrically stimulating certain parts of the nerve in order to create feeling in the hand. Cuff electrodes have an advantage over standard electrodes as they have high selective stimulation by bringing the electrical interface close to the neural tissue in order to selectively activate targeted regions of a peripheral nerve. In order to further improve the selective stimulation of these nerve cuffs, there is need for finer spatial resolution among electrodes. One method to achieve a higher spatial resolution is to increase the electrode density on the cuff itself. Microfabrication techniques can be used to achieve this higher electrode density. Using L-Edit, a layout editor, microfabricated peripheral nerve cuffs were designed with a higher electrode density than the current model. This increase in electrode density translates to an increase in spatial resolution by at least one order of magnitude. Microfabricated devices also have two separate components that are necessary to understand before implantation: lifetime of the device and assembly to prevent nerve damage. Silicone molding procedures were optimized so that devices do not damage nerves in vivo, and lifetime testing was performed on test microfabricated devices to determine their lifetime in vivo. Future work of this project would include fabricating some of the designed devices and seeing how they compare to the current cuffs in terms of their electrical performance, lifetime, shape, and mechanical properties.« less

Mirror Therapy and Transcutaneous Electrical Nerve Stimulation for Management of Phantom Limb Pain in Amputees - A Single Blinded Randomized Controlled Trial.

PubMed

Tilak, Merlyn; Isaac, Serin Anna; Fletcher, Jebaraj; Vasanthan, Lenny Thinagaran; Subbaiah, Rajalakshmi Sankaran; Babu, Andrew; Bhide, Rohit; Tharion, George

2016-06-01

Phantom limb pain (PLP) can be disabling for nearly two thirds of amputees. Hence, there is a need to find an effective and inexpensive treatment that can be self administered. Among the non-pharmacological treatment for PLP, transcutaneous electrical nerve stimulation (TENS) applied to the contralateral extremity and mirror therapy are two promising options. However, there are no studies to compare the two treatments. The purpose of this study is to evaluate and compare mirror therapy and TENS in the management of PLP in subjects with amputation. The study was an assessor blinded randomized controlled trial conducted at Physiotherapy Gymnasium of Physical Medicine and Rehabilitation Department, Christian Medical College, Vellore. Twenty-six subjects with PLP consented to participate. An initial assessment of pain using visual analogue scale (VAS) and universal pain score (UPS) was performed by a therapist blinded to the treatment given. Random allocation into Group I-mirror therapy and Group II-TENS was carried out. After 4 days of treatment, pain was re-assessed by the same therapist. The mean difference in Pre and Post values were compared among the groups. The change in pre-post score was analyzed using the paired t test. Participants of Group I had significant decrease in pain [VAS ( p = 0.003) and UPS ( p = 0.001)]. Group II also showed a significant reduction in pain [VAS ( p = 0.003) and UPS ( p = 0.002)]. However, no difference was observed between the two groups [VAS ( p = 0.223 and UPS ( p = 0.956)]. Both Mirror Therapy and TENS were found to be effective in pain reduction on a short-term basis. However, no difference between the two groups was found. Substantiation with long-term follow-up is essential to find its long-term effectiveness. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Preliminary development of a diabetic foot ulcer database from a wound electronic medical record: a tool to decrease limb amputations.

PubMed

Golinko, Michael S; Margolis, David J; Tal, Adit; Hoffstad, Ole; Boulton, Andrew J M; Brem, Harold

2009-01-01

Our objective was to create a practical standardized database of clinically relevant variables in the care of patients with diabetes and foot ulcers. Numerical clinical variables such as age, baseline laboratory values, and wound area were extracted from the wound electronic medical record (WEMR). A coding system was developed to translate narrative data, culture, and pathology reports into discrete, quantifiable variables. Using data extracted from the WEMR, a diabetic foot ulcer-specific database incorporated the following tables: (1) demographics, medical history, and baseline laboratory values; (2) vascular testing data; (3) radiology data; (4) wound characteristics; and (5) wound debridement data including pathology, culture results, and amputation data. The database contains variables that can be easily exported for analysis. Amputation was studied in 146 patients who had at least two visits (e.g., two entries in the database). Analysis revealed that 19 (13%) patients underwent 32 amputations (nine major and 23 minor) in 23 limbs. There was a decreased risk of amputation, 0.87 (0.78, 1.00), using a proportional hazards model, associated with an increased number of visits and entries in the WEMR. Further analysis revealed no significant difference in age, gender, HbA1c%, cholesterol, white blood cell count, or prealbumin at baseline, whereas hemoglobin and albumin were significantly lower in the amputee group (p<0.05) than the nonamputee group. Fifty-nine percent of amputees had histological osteomyelitis based on operating room biopsy vs. 45% of nonamputees. In conclusion, tracking patients with a WEMR is a tool that could potentially increase patient safety and quality of care, allowing clinicians to more easily identify a nonhealing wound and intervene. This report describes a method of capturing data relevant to clinical care of a patient with a diabetic foot ulcer, and may enable clinicians to adapt such a system to their own patient population.

Musculoskeletal model-based control interface mimics physiologic hand dynamics during path tracing task

NASA Astrophysics Data System (ADS)

Crouch, Dustin L.; (Helen Huang, He

2017-06-01

Objective. We investigated the feasibility of a novel, customizable, simplified EMG-driven musculoskeletal model for estimating coordinated hand and wrist motions during a real-time path tracing task. Approach. A two-degree-of-freedom computational musculoskeletal model was implemented for real-time EMG-driven control of a stick figure hand displayed on a computer screen. After 5-10 minutes of undirected practice, subjects were given three attempts to trace 10 straight paths, one at a time, with the fingertip of the virtual hand. Able-bodied subjects completed the task on two separate test days. Main results. Across subjects and test days, there was a significant linear relationship between log-transformed measures of accuracy and speed (Pearson’s r  =  0.25, p  <  0.0001). The amputee subject could coordinate movement between the wrist and MCP joints, but favored metacarpophalangeal joint motion more highly than able-bodied subjects in 8 of 10 trials. For able-bodied subjects, tracing accuracy was lower at the extremes of the model’s range of motion, though there was no apparent relationship between tracing accuracy and fingertip location for the amputee. Our result suggests that, unlike able-bodied subjects, the amputee’s motor control patterns were not accustomed to the multi-joint dynamics of the wrist and hand, possibly as a result of post-amputation cortical plasticity, disuse, or sensory deficits. Significance. To our knowledge, our study is one of very few that have demonstrated the real-time simultaneous control of multi-joint movements, especially wrist and finger movements, using an EMG-driven musculoskeletal model, which differs from the many data-driven algorithms that dominate the literature on EMG-driven prosthesis control. Real-time control was achieved with very little training and simple, quick (~15 s) calibration. Thus, our model is potentially a practical and effective control platform for multifunctional myoelectric prostheses that could restore more life-like hand function for individuals with upper limb amputation.

Peak pressure data and pressure-time integral in the contralateral limb in patients with diabetes and a trans-tibial prosthesis.

PubMed

Borg, Jael; Mizzi, Stephen; Formosa, Cynthia

2018-05-19

Clinicians currently rely on observational clinical data pertaining to the biomechanics of the diabetic foot. However, advances in technology can objectively describe this. A thorough understanding of the functional and mechanical consequences following trans-tibial amputations is lacking. Does a trans-tibial prostheses significantly increase peak plantar pressures and pressure time integrals in the intact foot of patients with type-2 diabetes and neuropathy? A prospective quantitative matched-subject design was employed. Twenty participants living with diabetes and peripheral sensory neuropathy were recruited. Ten participants presented with a trans-tibial amputation and 10 had intact feet. Participants were matched for gender, age, foot type and BMI. Peak plantar pressure and pressure time integral data were recorded using the Tekscan HR™ pressure mat system, using the two-step gait protocol. The Shapiro-Wilk test was used to determine normality of data. The Independent Samples t-test and the Mann Whitney U test were carried out to reject the null hypothesis. Although no significant differences (p < 0.05) in mean peak plantar pressures were observed in all the foot masks analysed between the amputee and the control group, a significant difference (p = 0.002) in mean pressure time integrals was recorded with highest pressure time integral (PTI) values under the 2nd-4th metatarsophalangeal joint (MTP joint) for the trans-tibial amputee group. Cumulative exposure of both pressure and time can lead to tissue damage. PTI could be considered as an important contributory factor in determining ulcer formation. Elevated PTI under the 2nd-4th MTP joints sustained in the intact contralateral limb in patients using below knee prosthesis could possibly be due to gait alterations in this population. The preservation of the contralateral limb is of great concern and importance as this might impact patient's mobility and quality of life. Copyright © 2018 Elsevier B.V. All rights reserved.

The effect of changing the inertia of a trans-tibial dynamic elastic response prosthesis on the kinematics and ground reaction force patterns.

PubMed

Hillery, S C; Wallace, E S; McIlhagger, R; Watson, P

1997-08-01

The aim of this study was to assess, by means of gait analysis, the effect on the gait of a trans-tibial amputee of altering the mass and the moment of inertia of a dynamic elastic response prosthesis. One male amputee was analysed for four to five walking trials at normal and fast cadences, using the VICON system of motion analysis and an AMTI force plate. The kinematic variables of cadence, swing time, single support time and joint angles for the knee and hip on the affected and intact sides were analysed. The ground reaction force was also analysed. The sample size was limited to one as an example to indicate the changes which are possible through simply changing the inertial characteristics. Descriptive statistics are used to demonstrate these changes. Three mass conditions for the prosthesis were analysed m1: 1080g; m2: 1080 + 530g; m3: 1080 + 1460g. The m1 condition is the mass of the prosthesis with no added weight while m2 and m3 were attachments of the same geometrical shape but were made from different materials. It was felt that the large mass range would highlight biomechanical adjustments as a result of its alteration. The effect on selected temporal characteristics were that as the speed increased the cadence changed and the affected side single support times as a percentage of the gait cycle were altered. The effect on the joint angles was also apparent at the hip and knee of both sides. The ground reaction force patterns were similar for all three mass conditions, though the impact peak which was evident in the intact limb was missing, indicating a shock absorbing property in the prosthesis. Clearly, changing the mass and moment of inertia has an effect on the kinematic variables of gait and should be considered when designing a prosthesis.

Kinematics in the terminal swing phase of unilateral transfemoral amputees: microprocessor-controlled versus swing-phase control prosthetic knees.

PubMed

Mâaref, Khaled; Martinet, Noël; Grumillier, Constance; Ghannouchi, Slaheddine; André, Jean Marie; Paysant, Jean

2010-06-01

To analyze the spatiotemporal parameters in the terminal swing phase of the prosthetic limb in unilateral transfemoral amputees (TFAs) compared with a group of asymptomatic subjects, and to identify a latency period (LP) in the TFA between the full extension of the prosthetic knee and the initial ground contact of the ipsilateral foot. To study the correlation between the LP and the duration of the swing phase. To evaluate the influence of the type of knee, the time since amputation, and the amputation level on the latency period. Three-dimensional gait analysis with an optoelectronic device. Gait analysis laboratory of a re-education and functional rehabilitation service. TFA (n=29) and able-bodied (n=15) subjects. Not applicable. Spatiotemporal and kinematics gait parameters. The swing phase and the LP of the prosthetic limb, associated with a consequently longer single-limb stance phase in the intact limb, were significantly longer than those measured in the intact limbs of these subjects, as well as those measured on both lower limbs of the able-bodied subjects (P<.05). There is a positive correlation (P<.05; r(2)=.58 between the LP and the swing phase on the TFA's prosthetic side. The LP measured in the prosthetic limb of TFA with a swing-phase control prosthetic knee is significantly greater than in those using the microprocessor-controlled prosthetic knee (P<.05). Of negligible duration in able-bodied subjects and in the intact limb of TFA, the LP is significantly greater in the prosthetic limb. It can explain the lengthened swing phase on the prosthetic side of those subjects. The use of a microprocessor-controlled prosthetic knee allows the LP to be reduced. This LP appears to be necessary to insure the stability of the prosthetic knee. We suggest calling this time "confidence time." Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Integrated and flexible multichannel interface for electrotactile stimulation

NASA Astrophysics Data System (ADS)

Štrbac, Matija; Belić, Minja; Isaković, Milica; Kojić, Vladimir; Bijelić, Goran; Popović, Igor; Radotić, Milutin; Došen, Strahinja; Marković, Marko; Farina, Dario; Keller, Thierry

2016-08-01

Objective. The aim of the present work was to develop and test a flexible electrotactile stimulation system to provide real-time feedback to the prosthesis user. The system requirements were to accommodate the capabilities of advanced multi-DOF myoelectric hand prostheses and transmit the feedback variables (proprioception and force) using intuitive coding, with high resolution and after minimal training. Approach. We developed a fully-programmable and integrated electrotactile interface supporting time and space distributed stimulation over custom designed flexible array electrodes. The system implements low-level access to individual stimulation channels as well as a set of high-level mapping functions translating the state of a multi-DoF prosthesis (aperture, grasping force, wrist rotation) into a set of predefined dynamic stimulation profiles. The system was evaluated using discrimination tests employing spatial and frequency coding (10 able-bodied subjects) and dynamic patterns (10 able-bodied and 6 amputee subjects). The outcome measure was the success rate (SR) in discrimination. Main results. The more practical electrode with the common anode configuration performed similarly to the more usual concentric arrangement. The subjects could discriminate six spatial and four frequency levels with SR >90% after a few minutes of training, whereas the performance significantly deteriorated for more levels. The dynamic patterns were intuitive for the subjects, although amputees showed lower SR than able-bodied individuals (86% ± 10% versus 99% ± 3%). Significance. The tests demonstrated that the system was easy to setup and apply. The design and resolution of the multipad electrode was evaluated. Importantly, the novel dynamic patterns, which were successfully tested, can be superimposed to transmit multiple feedback variables intuitively and simultaneously. This is especially relevant for closing the loop in modern multifunction prostheses. Therefore, the proposed system is convenient for practical applications and can be used to implement sensory perception training and/or closed-loop control of myoelectric prostheses, providing grasping force and proprioceptive feedback.

The biology of skin wetness perception and its implications in manual function and for reproducing complex somatosensory signals in neuroprosthetics.

PubMed

Filingeri, Davide; Ackerley, Rochelle

2017-04-01

Our perception of skin wetness is generated readily, yet humans have no known receptor (hygroreceptor) to signal this directly. It is easy to imagine the sensation of water running over our hands or the feel of rain on our skin. The synthetic sensation of wetness is thought to be produced from a combination of specific skin thermal and tactile inputs, registered through thermoreceptors and mechanoreceptors, respectively. The present review explores how thermal and tactile afference from the periphery can generate the percept of wetness centrally. We propose that the main signals include information about skin cooling, signaled primarily by thinly myelinated thermoreceptors, and rapid changes in touch, through fast-conducting, myelinated mechanoreceptors. Potential central sites for integration of these signals, and thus the perception of skin wetness, include the primary and secondary somatosensory cortices and the insula cortex. The interactions underlying these processes can also be modeled to aid in understanding and engineering the mechanisms. Furthermore, we discuss the role that sensing wetness could play in precision grip and the dexterous manipulation of objects. We expand on these lines of inquiry to the application of the knowledge in designing and creating skin sensory feedback in prosthetics. The addition of real-time, complex sensory signals would mark a significant advance in the use and incorporation of prosthetic body parts for amputees in everyday life. NEW & NOTEWORTHY Little is known about the underlying mechanisms that generate the perception of skin wetness. Humans have no specific hygroreceptor, and thus temperature and touch information combine to produce wetness sensations. The present review covers the potential mechanisms leading to the perception of wetness, both peripherally and centrally, along with their implications for manual function. These insights are relevant to inform the design of neuroengineering interfaces, such as sensory prostheses for amputees. Copyright © 2017 the American Physiological Society.

The prevalence of symptoms of Post-Traumatic Stress Disorder among soldiers with amputation of a limb or spinal injury: a report from a rehabilitation centre in Sri Lanka.

PubMed

Abeyasinghe, N L; de Zoysa, P; Bandara, K M K C; Bartholameuz, N A; Bandara, J M U J

2012-01-01

Post-Traumatic Stress Disorder has been identified as one of the most commonly occurring mental illnesses in combatants. This study was conducted to determine the prevalence of Post-Traumatic Stress Disorder among soldiers who had undergone amputation of a lower or an upper limb or sustained a spinal cord injury in the battlefield, and to compare the prevalence among these categories. The research presented seeks to increase the awareness of this condition among those treating war casualties so that appropriate treatment choices could be made to address them. The study was carried out in 2009 at a rehabilitation centre for combatants of war. Data were collected from 96 male army veterans between the ages of 18-49 years using a pre-tested self-administered questionnaire based on the Diagnostic and Statistical Manual of Mental Disorders, the Impact of Event Scale and the PTSD symptom scale. Soldiers with injuries sustained at least four weeks prior to the study were selected by a convenience sampling technique. Soldiers with multiple injuries, head injuries or those diagnosed with psychiatric disorders were excluded. The results revealed that 41.7% of the study population was compatible with the diagnosis of Post-Traumatic Stress Disorder. Within the three groups, 42.5% of the lower limb amputees, 33.3% of the upper limb amputees and 45.7% of the participants with spinal cord injury had symptoms compatible with Post-Traumatic Stress Disorder. There was no difference between the prevalence among the different injury categories considered. This study highlights the need to pay more attention in providing psychological care as a part of the overall health management of injured combatants. Early preparation of soldiers for stressors of war and screening for and proper management of Post-Traumatic Stress Disorder will improve the overall outcome of rehabilitation.

Applying Space Technology to Enhance Control of an Artificial Arm for Children and Adults With Amputations

NASA Technical Reports Server (NTRS)

Atkins, Diane J.

1998-01-01

The first single function myoelectric prosthetic hand was introduced in the 1960's. This hand was controlled by the electric fields generated by muscle contractions in the residual limb of the amputee user. Electrodes and amplifiers, embedded in the prosthetic socket, measured these electric fields across the skin, which increase in amplitude as the individual contracts their muscle. When the myoelectric signal reached a certain threshold amplitude, the control unit activated a motor which opened or closed a hand-like prosthetic terminal device with a pincher grip. Late in the 1990's, little has changed. Most current myoelectric prostheses still operate in this same, single-function way. To better understand the limitations of the current single-function myoelectric hand and the needs of those who use them, The Institute for Rehabilitation and Research (TIRR), sponsored by the National Institutes of Health (NUH), surveyed approximately 2,500 individuals with upper limb loss [1]. When asked to identify specific features of their current myoelectric prostheses that needed improvement, the survey respondents overwhelmingly identified the lack of wrist and finger movement, as well as poor control capability. However, simply building a mechanism with individual finger and wrist motion is not enough. In the 1960's and 1970's, engineers built a number of more dexterous prosthetic hands. Unfortunately, these were rejected during clinical trials due to a difficult and distracting control interface. The goal of this project, "Applying Space Technology to Enhance Control of an Artificial Arm for Children and Adults with Amputations," was to lay the foundation for a multi-function, intuitive myoelectric control system which requires no conscious thought to move the hand. We built an extensive myoelectric signal database for six motions from ten amputee volunteers, We also tested a control system based on new artificial intelligence techniques on the data from two of these subjects. This data is available to anyone doing myoelectric control research. Its availability is an important contribution to the prosthetics research community, as many researchers do not have access to amputee subjects. Since we collected myoelectric data from subjects' sound arms as well as their residual arms, this database will also prove useful to virtual reality and robotics researchers who want to explore myoelectric-based interfaces between any user and a machine. Currently, one small company (Intelligenta, Inc.) and one university (University of New Brunswick, Canada) are using this myoelectric database under other funding to develop multifunction control systems for prostheses. A prosthetics manufacturer (Liberty Technology, Inc.) is making plans to incorporate the results of their work into an artificial hand capable of several different movements to provide functionality only dreamed of by current myoelectric users. Methods Six adults and four children, all with unilateral, below-elbow amputations served as subjects. Five of the adults (3 male, 2 female, average age 34 years) had amputations due to traumatic injury, while one adult (female, age 32 years) and the four children (3 male, 1 female, average age 13 years) had congenital (i.e. from birth) limb deficiencies.

Targeted Muscle Reinnervation for Transradial Amputation: Description of Operative Technique.

PubMed

Morgan, Emily N; Kyle Potter, Benjamin; Souza, Jason M; Tintle, Scott M; Nanos, George P

2016-12-01

Targeted muscle reinnervation (TMR) is a revolutionary surgical technique that, together with advances in upper extremity prostheses and advanced neuromuscular pattern recognition, allows intuitive and coordinated control in multiple planes of motion for shoulder disarticulation and transhumeral amputees. TMR also may provide improvement in neuroma-related pain and may represent an opportunity for sensory reinnervation as advances in prostheses and haptic feedback progress. Although most commonly utilized following shoulder disarticulation and transhumeral amputations, TMR techniques also represent an exciting opportunity for improvement in integrated prosthesis control and neuroma-related pain improvement in patients with transradial amputations. As there are no detailed descriptions of this technique in the literature to date, we provide our surgical technique for TMR in transradial amputations.

[The function, activity and participation: the occupational reintegration].

PubMed

Zampolini, Mauro

2015-01-01

The return to work is a significant outcome after amputation. To reach this goal it is necessary to measure properly this process. Unfortunately, for amputee, we have different scales but often focused on specific groups of problems The International Classification of funtioning (ICF) can constitute the frame of reference where to converge scales available and according to which define problems related to disability. For the person amputated the theme of the return to work arises differently for the conditions traumatic and non-traumatic. For the first return to work is a priority given the younger age. For the latter, given the advanced age, the return to work is likely to be a measure of the success of rehabilitation is not particularly relevant.

Non-normative bodies, rationality, and legal personhood.

PubMed

Travis, Mitchell

2014-01-01

This article questions how legal personhood is constructed by law. Elective amputation is used as a way of interrogating the institutional, material, and discursive relations that combine in order to suspend legal personhood. Elective amputation is introduced in terms of medical and psychological explanations. Additionally, the perspective of self-identified elective amputees who choose to share their stories through online blogs is utilised to gain a narrative sense of how these individuals understand and engage with law. In particular, the areas of disability, sexuality, and rationality are used to exemplify law's continuing commitment to normative embodiment as grounds for ascribing legal personhood. © The Author [2014]. Published by Oxford University Press; all rights reserved. For Permissions, please email: journals.permissions@oup.com.

Amputees by choice: body integrity identity disorder and the ethics of amputation.

PubMed

Bayne, Tim; Levy, Neil

2005-01-01

Should surgeons be permitted to amputate healthy limbs if patients request such operations? We argue that if such patients are experiencing significant distress as a consequence of the rare psychological disorder named Body Integrity Identity Disorder (BIID), such operations might be permissible. We examine rival accounts of the origins of the desire for healthy limb amputations and argue that none are as plausible as the BIID hypothesis. We then turn to the moral arguments against such operations, and argue that on the evidence available, none is compelling. BIID sufferers meet reasonable standards for rationality and autonomy: so as long as no other effective treatment for their disorder is available, surgeons ought to be allowed to accede to their requests.

[Phantom limb pain syndrome: therapeutic approach using mirror therapy in a Geriatric Department].

PubMed

González García, Paloma; Manzano Hernández, M Pilar; Muñoz Tomás, M Teresa; Martín Hernández, Carlos; Forcano García, Mercedes

2013-01-01

The clinical use of mirror visual feedback was initially introduced to alleviate phantom pain by restoring motor function through plastic changes in the human primary motor cortex. It is a promising novel technique that gives a new perspective to neurological rehabilitation. Using this therapy, the mirror neuron system is activated and decrease the activity of those systems that perceive protopathic pain, making somatosensory cortex reorganization possible. This paper reports the results of the mirror therapy in three patients with phantom limb pain after recent lower limb amputation, showing its analgesic effects and its benefits as a comprehensive rehabilitation instrument for lower limb amputee geriatric patients. Copyright © 2012 SEGG. Published by Elsevier Espana. All rights reserved.

Evolution of one-handed piano compositions.

PubMed

Drozdov, Ignat; Kidd, Mark; Modlin, Irvin M

2008-01-01

Electronic searches were performed to investigate the evolution of one-handed piano compositions and one-handed music techniques, and to identify individuals responsible for the development of music meant for playing with one hand. Particularly, composers such as Liszt, Ravel, Scriabin, and Prokofiev established a new model in music by writing works to meet the demands of a variety of pianist-amputees that included Count Géza Zichy (1849-1924), Paul Wittgenstein (1887-1961), and Siegfried Rapp (b. 1915). Zichy was the first to amplify the scope of the repertoire to improve the variety of one-handed music; Wittgenstein developed and adapted specific and novel performance techniques to accommodate one-handedness; and Rapp sought to promote the stature of one-handed pianists among a musically sophisticated public able to appreciate the nuances of such maestros.

Low-cost assistive device for hand gesture recognition using sEMG

NASA Astrophysics Data System (ADS)

Kainz, Ondrej; Cymbalák, Dávid; Kardoš, Slavomír.; Fecil'ak, Peter; Jakab, František

2016-07-01

In this paper a low-cost solution for surface EMG (sEMG) signal retrieval is presented. The principal goal is to enable reading the temporal parameters of muscles activity by a computer device, with its further processing. Paper integrates design and deployment of surface electrodes and amplifier following the prior researches. Bearing in mind the goal of creating low-cost solution, the Arduino micro-controller was utilized for analog-to-digital conversion and communication. The software part of the system employs support vector machine (SVM) to classify the EMG signal, as acquired from sensors. Accuracy of the proposed solution achieves over 90 percent for six hand movements. Proposed solution is to be tested as an assistive device for several cases, involving people with motor disabilities and amputees.