Functional and perceptive differences between conventional and advanced ankle foot orthoses in community ambulators post-limb trauma: the injuries managed with advanced bracing of the lower extremity (IM ABLE) study.

Introduction: Many military service members and civilians suffer from lower extremity trauma. Despite recent advancements in lower limb bracing technology, it remains unclear whether these newer advanced braces offer improved comfort and functionality compared to conventional options. The IDEO (Intrepid Dynamic Exoskeletal Orthosis), a type of "advanced" orthosis was developed to assist in maintaining high functional performance in patients who have experienced high-energy lower extremity trauma and underwent limb salvage surgeries. Methods: A cross-sector multi-site initiative was completed to study the efficacy of advanced ankle foot orthoses (AFO) for lower limb trauma and injury compared to a conventional AFO. Following fitting, training, and accommodation, the subjects were assessed in each AFO system for mobility, self-reported function, safety and pain, and preference. Results: They preferred the advanced over the conventional AFO and the mobility and exertion perception improved with the advanced AFO with no difference in pain or overall health status scores. Discussion: Thus, an advanced AFO is an option for trauma affecting the lower limb. Long-term studies are required to better understand the accommodation and learning process of using an advanced AFO.

A systematic literature review of ankle-foot orthosis and functional electrical stimulation foot-drop treatments for persons with multiple sclerosis.

Foot-drop is one of the most diagnosed and physically limiting symptoms persons with multiple sclerosis (pwMS) experience. Clinicians prescribe ankle-foot orthosis (AFO) and functional electrical stimulation (FES) devices to help alleviate the effects of foot drop, but it is unclear how their clinical and functional gait improvements compare given the user's level of disability, type of multiple sclerosis, walking environment, or desired physical activity. The research questions explored were what is the current state of AFO and FES research for pwMS? What are the prevailing research trends? What definitive clinical and functional device comparisons exist for pwMS? eight databases were systematically searched for relevant literature published between 2009 and 2021. The American Association of Orthotists and Prosthetists and Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines for systematic literature reviews were followed. A team of 3 researchers critically evaluated 17 articles that passed eligibility criteria. This review discusses the current state and trends of research, provides evidence statements on device effects, and recommends improvements for future studies. A meta-analysis would be informative, but study variability across the literature makes directly comparing AFO and FES device effects unreliable. This review contributes new and useful information to multiple sclerosis literature that can be used by both clinicians and researchers. Clinicians can use the provided insights to prescribe more effective, customized treatments, and other researchers can use them to evaluate and design future studies.

Biomechanics of healthy subjects during exercise on a simulated vibration isolation and stabilization system.

With long-term space flights being planned for the Moon and Mars, proper countermeasures must be taken to facilitate human health in microgravity environments. Exercise is a vital countermeasure used to prevent bone and muscle loss, among other health interests. Future exploration missions encourage creating an exercise device that is both compact and can be used to properly execute exercise by the astronauts. Current design considerations include interfacing an exercise device with a vibration isolation and stabilization (VIS) system, which is necessary for protecting the spacecraft and sensitive experiments from harmful vibrations developed during repetitive exercise. This human factor study assesses the feasibility of a VIS system exercise device by using the Computer Assistive Rehabilitation Environment (CAREN) to simulate characteristics of the system. The CAREN includes a 6 degree of freedom (DOF) platform, force plates and a motion capture system. An algorithm was developed using the D-Flow software to move the platform in 1 and 2 DOF sinusoidal responses. Multiple sinusoidal frequencies for platform motion during subject exercise were evaluated. Four subjects completed squat and row exercises on the CAREN while their motion was recorded. Kinematic and kinetic data were collected from each subject. Trials were executed with 1-2 DOF motion in heave and pitch. Results conclude that subjects completed exercises with adequate range of motion (ROM) and ground reaction forces (GRF) during each trial. Certain environments, such as movement at a slower frequency (0.10 Hz) and movement of heave and pitch at differing frequencies, caused loss of balance indicated by grabbing of the handrail in some subjects and difficulty in synchronization between the subjects and the platform. This indicates that VIS system design should focus on frequency of movements centering around subjects' natural exercise frequencies if possible. This study serves as a proof of concept for using CAREN and programming tool D-Flow to simulate platform movement on VIS system design. Further experimentation will test more detailed designs, including active and passive systems that will move based on real-time subject data.

Effect of transfemoral prosthetic socket interface design on gait, balance, mobility, and preference: A randomized clinical trial.

BACKGROUND: There are alternative transfemoral (TF) socket interface designs that have not been compared with the standard of care, ischial ramus containment (IRC). The interface directly affects performance. OBJECTIVES: To compare 3 TF interface designs, IRC, dynamic socket (DS), and subischial (Sub-I), regarding gait, balance, mobility, and preference. The authors hypothesized that these more active users may experience gait, mobility, and preference benefits from the less intrusive DS and Sub-I interface designs. STUDY DESIGN: Single-blind, repeated-measures, 3-period randomized controlled crossover clinical trial. METHODS: People with unilateral TF amputation with 1 year or longer prosthesis use experience, independent community ambulatory status, 18 to 60 years of age, of any race or ethnicity, with a body mass of 45 to 125 kg, and with a self-reported ability to walk for 20 minutes continuously were included in the study. Each participant was fit in all 3 interface designs. RESULTS: Thirteen participants completed the clinical trial. Velocity, cadence, mobility, and balance were not statistically different between the 3 socket conditions. The DS demonstrated significantly greater symmetry in swing, stance, single support percentage, and toe angle compared with IRC and Sub-I. Sixty days after study completion, 7 participants changed interfaces, trending away from IRC. CONCLUSIONS: Large differences were not observed. Small differences in spatiotemporal gait measures combined with patient preference may make a meaningful difference to individual patients and should be considered.

The effect of the transfemoral prosthetic socket interface designs on skeletal motion and socket comfort: A randomized clinical trial.

BACKGROUND: The most crucial aspect of a prosthesis is the socket, as it will directly determine gait stability and quality. The current standard of care ischial ramus containment socket is reported to increase coronal stability through gait; however, socket discomfort is the primary complaint among prosthetic users. OBJECTIVES: The purpose of this study is to compare ischial ramus containment to alternatives in the transfemoral amputee population. All subjects were fit with three different sockets: traditional ischial ramus containment, a dynamic socket, and a sub-ischial. In this study, authors hypothesized socket skeletal motion would be equivalent across interventions. STUDY DESIGN: Single-blind, repeated-measures, three-period randomized crossover clinical trial. METHODS: Outcome measures were socket comfort score and skeletal motion, viewed coronally with X-ray measuring the position of the skeleton in relationship to the socket in full weight-bearing and full un-loading. RESULTS: The mean age was 38.2 and mean Amputee Mobility Predictor score was 40. Mean vertical movement, horizontal movement, single limb prosthetic stance, mean femoral adduction in swing and stance, and median socket comfort score were not statistically different. CONCLUSION: The socket design did not significantly effect skeletal motion and socket comfort. All socket designs are suitable depending on the patient-centric preferences and prosthetist skill set. CLINICAL RELEVANCE: The comfort of the standard of care transfemoral amputation socket has been widely reported as problematic. A comparison of alternative designs in a controlled clinical trial environment will assist the clinician in understanding the impact of design regarding skeletal motion and comfort. Users could benefit from alternatives applied in clinical practice.

Enhanced Control to Improve Navigation and Manipulation of Power Wheelchairs.

Our team developed a mobile wheelchair control kit designed to allow power wheelchair users the ability to maneuver their wheelchair without the need to manipulate a joystick with their hands. A smartphone and its internal accelerometer sensor was used to detect the vector of gravity, and thus detecting the pitch and roll. The wheelchair control system was tested with the phone attached in three mounting positions: hand held, hat and arm band and compared to the manipulation using the wheelchair joystick. To determine the viability of the commercialization of this kit as well as which features to further develop, a customer discovery was completed. Over a hundred interviews of power wheelchairs users, therapists, care takers, manufacturers, dealers, and assistive technology professionals were conducted at clinics, tradeshows, disabilities support groups, and rehabilitation organizations. After discovering the needs of the customers, collision avoidance was implemented into the control kit and back up cameras were added into the smart phone app to allow for the camera view to be seen without additional screens attached to the wheelchair. Future work will test these new design features and will concentrate on removing excess weight from the control kit. Improving the ease of installation of the kit to any power wheelchair will also be a focus.

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

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.

EFFECTS OF THE GENIUM KNEE SYSTEM ON FUNCTIONAL LEVEL, STAIR AMBULATION, PERCEPTIVE AND ECONOMIC OUTCOMES IN TRANSFEMORAL AMPUTEES.

Compared to non-microprocessor knees, the C-Leg microprocessor knee (MPK) is bioenergentically and economically more efficient and safer for transfemoral amputation (TFA) patients. The Genium MPK has demonstrated improvements in perceived function, knee kinematics, and physical functional performance compared to C-Leg. Clinical and health economic analyses have not been conducted with the Genium knee system. The purpose of this study was to determine if laboratory determined benefits of Genium are detectable using common clinical assessments and if there are economic benefits associated with its use. This study utilized a randomized AB crossover study with 60 d follow-up including cost-effectiveness analysis. Twenty TFA patients tested with both knees in mobility and preference measures. Incremental cost-effectiveness ratios (ICER) were calculated based on performance measures. Stair Assessment Index scores improved with Genium. Mean stair completion times and descent stepping rate were not different between knees. Stair ascent stepping rate for C-Leg was greater compared with Genium (p = 0.04). Genium use decreased Four square step test completion time and increased functional level and step activity (p ≤ 0.05). Further, Genium use improved (p ≤ 0.05) function and safety in three out of five Activities of Daily Living (ADL) survey domains. Finally, more subjects preferred Genium following testing. Functional measures were used to calculate ICERs. ICER values for Genium fall within established likely-to-accept value ranges. Compared with C-Leg, Genium use improved stair walking performance, multi-directional stepping, functional level, and perceived function. In this group of community ambulators with TFA, Genium was preferred, and, while more costly, it may be worth funding due to significant improvements in functional performance with ADLs.

Functional performance differences between the Genium and C-Leg prosthetic knees and intact knees.

Microprocessor prosthetic knees (MPKs) have advanced technologically, offering new features to decrease impairment and activity limitations for persons with transfemoral amputation (TFA). The Genium knee is functionally untested, and functional differences between it and intact knees are unknown. This study sought to determine whether Genium use improves functional performance compared with the C-Leg. A randomized experimental crossover design was used, with a cross-section of five nonamputee controls for comparison to normal. Twenty community-ambulating persons with TFA were trained and tested for accommodation with study components. All subjects (n = 25) were assessed using the Continuous-Scale Physical Functional Performance-10 (CS-PFP10) assessment. Subjects with TFA used both MPK systems. Genium use improved upper-body flexibility, balance, and endurance domain scores (7.0%-8.4%, p

Differences in Military Obstacle Course Performance Between Three Energy-Storing and Shock-Adapting Prosthetic Feet in High-Functioning Transtibial Amputees: A Double-Blind, Randomized Control Trial.

BACKGROUND: Approximately 683 persons engaged in military service experienced transtibial amputation (TTA) related to recent war in Iraq and Afghanistan. Military TTAs function at a level beyond basic ambulation. No empirical data demonstrate which higher functioning prosthetic feet maximize injured service personnel's ability to continue performing at a level commensurate with return to duty. This study's purpose was to determine which of three high-functioning, energy-storing prosthetic feet maximize performance and preference in a field obstacle course (OC) and to quantify physical performance differences between TTAs and high-functioning nonamputees. PROCEDURES: A randomized, double-blind, repeated measures experimental design compared three prosthetic feet (Ossur Variflex, Endolite Elite Blade, and Ossur Re-Flex Rotate) during performance on a field OC. TTAs accommodated with study feet and the OC before assessment. 14 TTAs and 14 nonamputee controls completed the course. Subjective and objective performance differences were compared across feet conditions and between groups. RESULTS: Total OC completion times were similar between prosthetic feet: Elite-Blade (419 seconds ± 130), Variflex (425 seconds ± 144), and Re-Flex Rotate (444 seconds ± 220). Controls' OC completion time (287.2 seconds ± 58) was less (p ≤ 0.05) than TTA times. In total, controls had faster completion times (p ≤ 0.05) compared to all prosthetic feet conditions in 13/17 obstacles. Re-Flex Rotate had 2 additional obstacles different (p ≤ 0.05) than controls and required more time to complete. Median RPE values were lower (p ≤ 0.05) for controls than TTA regardless of foot. Regarding foot preference for OC completion, 7/14 (50%) preferred Elite Blade, 5/14 (36%) preferred Re-Flex Rotate, and the remaining 2/14 (14%) preferred Variflex. CONCLUSION: Controls completed the OC faster and with less effort than TTAs regardless of prosthetic foot. No clear differences in prosthetic feet emerged during OC completion; however, individual task performance, perceived effort, and preference resulted in trends of slight performance improvement with and preference for Elite Blade, a dual function energy-storing and return foot combined with vertical shock absorption. Understanding how to maximally improve performance in such functional tasks may allow service members to best sustain physical fitness, return to their military occupational specialty and possibly in-theater duty.

EFFECTS OF THE GENIUM MICROPROCESSOR KNEE SYSTEM ON KNEE MOMENT SYMMETRY DURING HILL WALKING.

Use of the Genium microprocessor knee (MPK) system reportedly improves knee kinematics during walking and other functional tasks compared to other MPK systems. This improved kinematic pattern was observed when walking on different hill conditions and at different speeds. Given the improved kinematics associated with hill walking while using the Genium, a similar improvement in the symmetry of knee kinetics is also feasible. The purpose of this study was to determine if Genium MPK use would reduce the degree of asymmetry (DoA) of peak stance knee flexion moment compared to the C-Leg MPK in transfemoral amputation (TFA) patients. This study used a randomized experimental crossover of TFA patients using Genium and C-Leg MPKs (n = 20). Biomechanical gait analysis by 3D motion tracking with floor mounted force plates of TFA patients ambulating at different speeds on 5° ramps was completed. Knee moment DoA was significantly different between MPK conditions in the slow and fast uphill as well as the slow and self-selected downhill conditions. In a sample of high-functioning TFA patients, Genium knee system accommodation and use improved knee moment symmetry in slow speed walking up and down a five degree ramp compared with C-Leg. Additionally, the Genium improved knee moment symmetry when walking downhill at comfortable speed. These results likely have application in other patients who could benefit from more consistent knee function, such as older patients and others who have slower walking speeds.

CONCURRENT VALIDITY OF THE CONTINUOUS SCALE-PHYSICAL FUNCTIONAL PEFORMANCE-10 (CS-PFP-10) TEST IN TRANSFEMORAL AMPUTEES.

The Continuous Scale-Physical Functional Performance-10 (CS-PFP-10) test consists of 10 standardized daily living tasks that evaluate overall physical functional performance and performance in five individual functional domains: upper body strength (UBS), upper body flexibility (UBF), lower body strength (LBS), balance and coordination (BAL), and endurance (END). This study sought to determine the concurrent validity of the CS-PFP-10 test and its functional domains that involve the lower extremities (LBS, BAL, or END) in comparison to measures that have established validity for use in persons with transfemoral amputation (TFA). Ten TFA patients functioning at K3 or higher (Medicare Functional Classification Level) completed the study. Participants were assessed performing the CS-PFP-10, Amputee Mobility Predictor (AMP), 75 m self-selected walking speed (75 m SSWS) test, timed down stair walking (DN stair time), and the limits of stability (LOS) balance test. Concurrent validity was assessed using correlation analysis. The AMP, 75 m SSWS, LOS, and the DN stair time tests were strongly correlated (r = ± 0.76 to 0.86) with their paired CS-PFP-10 domain score (LBS, BAL, or END) and CS-PFP-10 total score. These findings indicate that the lower limb and balance domains of the CS-PFP-10 are valid measures to assess the physical functional performance of TFA patients.

Correlations between residual limb length and joint moments during sitting and standing movements in transfemoral amputees.

BACKGROUND AND AIM: Longer residual limb lengths provide an increased lever arm. Longer residual limbs may produce increased joint moments; the two may be correlated. These correlations have not been evaluated in transfemoral amputees during transitional movements. Correlations between residual limb length and involved side joint moment could contribute to justification supporting maximal residual limb length preservation. This study investigated possible correlations between hip or knee moment and residual limb length. TECHNIQUE: Hip and knee joint moments were determined while 21 transfemoral amputees performed sitting and standing movements and then evaluated for correlation with residual limb length. DISCUSSION: Residual limb length was not correlated with either knee or involved side hip moments during sit to stand or stand to sit. Conversely, weak inverse correlations (p < 0.05) existed between sound hip moment magnitude and residual limb length. These correlations suggest that in community ambulating transfemoral amputees, longer residual limb length could decrease sound hip kinetic burden during transitional movement. Beyond correlations between residual limb length and sound hip transitional movement kinetics, there are other considerations in determining residual limb length during amputation. CLINICAL RELEVANCE: This study examines relationships between lower limb joint moments and residual limb length related to sit-to-stand and stand-to-sit activities. The results have implications for amputation surgery and rehabilitation.

Differences in myoelectric and body-powered upper-limb prostheses: Systematic literature review.

The choice of a myoelectric or body-powered upper-limb prosthesis can be determined using factors including control, function, feedback, cosmesis, and rejection. Although body-powered and myoelectric control strategies offer unique functions, many prosthesis users must choose one. A systematic review was conducted to determine differences between myoelectric and body-powered prostheses to inform evidence-based clinical practice regarding prescription of these devices and training of users. A search of 9 databases identified 462 unique publications. Ultimately, 31 of them were included and 11 empirical evidence statements were developed. Conflicting evidence has been found in terms of the relative functional performance of body-powered and myoelectric prostheses. Body-powered prostheses have been shown to have advantages in durability, training time, frequency of adjustment, maintenance, and feedback; however, they could still benefit from improvements of control. Myoelectric prostheses have been shown to improve cosmesis and phantom-limb pain and are more accepted for light=intensity work. Currently, evidence is insufficient to conclude that either system provides a significant general advantage. Prosthetic selection should be based on a patient's individual needs and include personal preferences, prosthetic experience, and functional needs. This work demonstrates that there is a lack of empirical evidence regarding functional differences in upper-limb prostheses.

Differences in knee flexion between the Genium and C-Leg microprocessor knees while walking on level ground and ramps.

BACKGROUND: 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. METHODS: 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. FINDINGS: 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. INTERPRETATION: 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.

Golf hand prosthesis performance of transradial amputees.

BACKGROUND: Typical upper limb prostheses may limit sports participation; therefore, specialized terminal devices are often needed. The purpose of this study was to evaluate the ability of transradial amputees to play golf using a specialized terminal device. CASE DESCRIPTION AND METHODS: Club head speed, X-factor, and elbow motion of two individuals with transradial amputations using an Eagle Golf terminal device were compared to a non-amputee during a golf swing. Measurements were collected pre/post training with various stances and grips. FINDINGS AND OUTCOMES: Both prosthesis users preferred a right-handed stance initially; however, after training, one preferred a left-handed stance. The amputees had slower club head speeds and a lower X-factor compared to the non-amputee golfer, but increased their individual elbow motion on the prosthetic side after training. CONCLUSION: Amputees enjoyed using the device, and it may provide kinematic benefits indicated by the increase in elbow flexion on the prosthetic side. CLINICAL RELEVANCE: The transradial amputees were able to swing a golf club with sufficient repetition, form, and velocity to play golf recreationally. Increased elbow flexion on the prosthetic side suggests a potential benefit from using the Eagle Golf terminal device. Participating in recreational sports can increase amputees' health and quality of life.

Study of variation in human upper body parameters and motion for use in robotics based simulation.

This paper reviews the variations in human upper body motion of subjects completing activities of daily living. This study was completed to serve as a reference to evaluate the quality of simulated of human motion. In this paper we define the variation in motion as the variation in subjects' parameters (link lengths), joint angles, and hand positions, for a given task. All of these variations are related by forward kinematic equations. Motion data from eight healthy right hand dominant adults performing three activities of daily living (brushing hair, drinking from a cup, and opening a door) were collected using an eight camera Vicon motion analysis system. Subject parameters were calculated using relative positions of functional joint center locations between segments. Joint angles were calculated by Euler angle rotations between body segments. Hand position was defined as the origin of the hand frame relative to the pelvis frame. The variance of recorded human motion was analyzed based on the standard deviations of subject parameters, joint angles, and hand positions. Variances in joint angles were found to be similar in magnitude to root mean squared error of kinematics based motion simulation. To evaluate the relative variance, the forward kinematic solutions of the trials were found after removing subject parameter variance and reducing joint angle variance. The variance in the forward kinematic solution was then compared to the recorded hand position variance. Reductions in subject parameter and joint angle variance produced a proportionally much smaller reduction in the calculated hand position variance. Using the average instead of individual subject parameters had only a small impact on hand position variance. Modifying joint angles to reduce variance had a greater impact on the calculated hand position variance than using average subject parameters, but was still a relatively small change. Future work will focus on using these results to create formalized procedures for quantifying the human likeness of artificial human motions, to serve as a basis for performance comparison between different methods.

Kinetic asymmetry in transfemoral amputees while performing sit to stand and stand to sit movements.

Transitional movements are a determinant of functional independence and have limited study in amputees. Microprocessor prosthetic knees' abilities to assist transfemoral amputees with sitting and standing have not been studied. Through cross-sectional study, 21 transfemoral amputees, divided into 3 groups of 7 by knee type (power knee, C-leg, Mauch SNS) and 7 non-amputee controls (n=28) performed sit to stand and stand to sit while kinematic and kinetic data were recorded. Transfemoral amputees can stand (1.6-2.0s) and sit (2.1-2.8s) at rates comparable to controls (1.6s). Controls' ground reaction force (GRF) and knee moment production was <7% asymmetric and superior to amputees' during both movements. For sit to stand, amputees' asymmetry for GRF ranged from 53 to 69% and 110 to 124% for knee moments. For stand to sit, amputees' asymmetry for GRF ranged from 32 to 60% and 84 to 114% for knee moments. Hip moment asymmetry for sit to stand was less for control (21%) and power knee (34%) groups than that produced by the Mauch SNS (59%) group. For stand to sit, hip moment production for the Mauch SNS (47%) and C-leg groups (71%) were more asymmetric than controls (19%). In the majority of cases transfemoral amputees do not load their prosthesis extensively for standing up or sitting down. Therefore, this transitional movement is currently a one-legged task, which increases stress on the sound limb. Generally, the prosthetic knees studied did not produce a significant knee moment in either task. Although most differences between knee groups were not statistically significant, differences may be clinically meaningful on an individual basis.

Compensatory movements of transradial prosthesis users during common tasks.

BACKGROUND: Recent studies have documented motions of the upper limbs of healthy subjects during activities of daily living. The aim of this study was to investigate compensatory motions of the upper extremity and torso during tasks for transradial prosthesis users and to determine if bracing simulates prosthesis use. METHODS: Seven transradial myoelectric prosthesis users and 10 non-amputee volunteers performed four common tasks. Bracing was used to simulate the use of a transradial prosthesis by the non-amputee subjects. Range of motion of the glenohumeral (shoulder) joint, elbow joint and torso were calculated from optical motion analysis data. The motions between the non-braced, braced and transradial prosthesis user groups were statistically compared. Degree of asymmetry between the affected and unaffected arm was computed for the bilateral tasks. FINDINGS: Myoelectric transradial prosthesis users compensate for lack of wrist and forearm movement differently depending on the task. Compensatory motion in torso bending occurs while opening a door. For the box lift task, prosthesis users rely more on the sound arm and torso bending. While drinking from a cup, decreasing flexion of the glenohumeral joint and increasing elbow flexion was shown while using a prosthesis. While turning a steering wheel, prosthesis users are similar to non-amputee subjects. INTERPRETATION: By looking at the compensatory motions caused by limiting forearm and wrist movement, a greater understanding of the problems with transradial prosthetic design can be developed. Although bracing intact subjects showed similar mechanisms of compensation in most tasks, the magnitude of compensation was greater for prosthesis users.