Factors influencing satisfaction with prosthetic and orthotic services - a national cross-sectional study in Sweden

PURPOSE

To evaluate client satisfaction with prosthetic and orthotic services in Sweden, determine if satisfaction differs between clients using different devices and identify factors which influence client satisfaction.

MATERIALS AND METHODS

A cross-sectional design was used to survey 7318 clients. The survey included items related to demographics, quality of life, device comfort, device use, the extent to which clients' needs were met and satisfaction with services. Ethics approval was provided by the Swedish Ethical Review Authority.

RESULTS

A total of 2925 surveys were returned reflecting a response rate of 41%. Mean OPUS-CSS point score was 61.9(SD 16.8) with differences observed between device categories (p < 0.001). Factors that were identified as most positively influencing client satisfaction were, being a limb prosthesis user and being under 65 years. When analysing scores for individual OPUS items breast prosthesis users scored higher than users of other devices. Clients were most satisfied with the level of respect they were shown by staff (mean = 2.72/3) and less satisfied with coordination of services with other therapists/doctors(mean = 1.88/3).

CONCLUSIONS

Prosthetic and orthotic users are reasonably satisfied with the services they receive. Attention should be directed towards understanding why prosthetic users are more satisfied than orthotic users and why clients under 65 years report higher satisfaction scores.

A pneumatic reconfigurable socket for transtibial amputees

Many transtibial amputees rate the fit between their residual limb and prosthetic socket as the most critical factor in satisfaction with using their prosthesis. This study aims to address the issue of prosthetic socket fit by reconfiguring the socket shape at the interface of the residual limb and socket. The proposed reconfigurable socket shifts pressure from sensitive areas and compensates for residual limb volume fluctuations, the most important factors in determining a good socket fit. Computed tomography scan images are employed to create the phantom limb of an amputee and to manufacture the reconfigurable socket. The performance of the reconfigurable socket was evaluated both experimentally and numerically using finite element modelling. The study showed that the reconfigurable socket can reduce interface pressure at targeted areas by up to 61%.

Proprioception: A New Era Set in Motion by Emerging Genetic and Bionic Strategies?

The generation of an internal body model and its continuous update is essential in sensorimotor control. Although known to rely on proprioceptive sensory feedback, the underlying mechanism that transforms this sensory feedback into a dynamic body percept remains poorly understood. However, advances in the development of genetic tools for proprioceptive circuit elements, including the sensory receptors, are beginning to offer new and unprecedented leverage to dissect the central pathways responsible for proprioceptive encoding. Simultaneously, new data derived through emerging bionic neural machine-interface technologies reveal clues regarding the relative importance of kinesthetic sensory feedback and insights into the functional proprioceptive substrates that underlie natural motor behaviors.

Artificially long legs directly enhance long sprint running performance

This comment addresses the incomplete presentation and incorrect conclusion offered in the recent manuscript of Beck et al. (R. Soc. Open Sci. 9, 211799 (doi:10.1098/rsos.211799)). The manuscript introduces biomechanical and performance data on the fastest-ever, bilateral amputee 400 m runner. Using an advantage standard of not faster than the fastest non-amputee runner ever (i.e. performance superior to that of the intact-limb world record-holder), the Beck et al. manuscript concludes that sprint running performance on bilateral, lower-limb prostheses is not unequivocally advantageous compared to the biological limb condition. The manuscript acknowledges the long-standing support of the authors for the numerous eligibility applications of the bilateral-amputee athlete. However, it does not acknowledge that the athlete's anatomically disproportionate prosthetic limb lengths (+15 cm versus the World Para Athletics maximum) are ineligible in both Olympic and Paralympic track competition due to their performance-enhancing properties. Also not acknowledged are the slower sprint performances of the bilateral-amputee athlete on limbs of shorter length that directly refute their manuscript's primary conclusion. Our contribution here provides essential background information and data not included in the Beck et al. manuscript that make the correct empirical conclusion clear: artificially long legs artificially enhance long sprint running performance.

Electromyography pattern-recognition based prosthetic limb control using various machine learning techniques

People who have lost their limbs to amputation and neurological disorders confront this loss every morning. As per the literature review, nearly 30% of the Indian population suffered from upper extremity amputation. As a coping-up measure, a force-controlled prosthetic limb has been developed to improve their self-reliance, quality of lifestyle and mental strength. The current prosthetic limb operation is done by residual muscle contraction, which contributes to the activation of the sensor and the motor. But there are some cons, the amputee does not know how much pressure needs to be exerted for holding various objects. Also, the amputee still has to undergo the surgical procedure. However, this paper proposes a way to predict the force which is needed to regulate the voltage for the servomotors using different Machine Learning (ML) regression approaches. Support Vector Regressor (SVR), Linear Regression and Random Forest models have been used to predict that force requirement. After comparing the results, the Random Forest model gave a highly accurate prediction of the force needed to control the voltage for the DC servomotors.

Cortical brain activity in transfemoral or knee-disarticulation prosthesis users performing single- and dual-task walking activities

Introduction

Walking with a prosthesis while performing secondary tasks increases demand on cognitive resources, compromising balance and gait. This study investigated effects of a secondary task on patterns of brain activity and temporospatial gait parameters in individuals using a prosthesis with or without a microprocessor-controlled prosthetic knee(MPK) and controls.

Methods

A cross-sectional study with repeated measures was performed. Twenty-nine individuals with amputations and 16 controls were recruited. Functional near-infrared spectroscopy was used to evaluate changes in oxygenated and de-oxygenated haemoglobin in the prefrontal cortex and temporospatial variables during single-and dual-task walking.

Results

Differences in brain activity were observed within the MPK-group and controls without changes in temporospatial parameters. The Trail-Walking test was associated with highest levels of brain activity in both groups. No differences were observed between single- and dual-task walking in the non-MPK-group (p > 0.05). The Non-MPK and the MPK-group recorded higher levels of brain activity than controls during single-task walking and poorer results on temporospatial variables compared to controls.

Conclusions

For the MPK-group and controls, introduction of a secondary task led to an increase in brain activity. This was not seen in the Non-MPK-group. Significant differences in brain activity were observed in the absence of changes in temporospatial parameters.

Perceived self-efficacy and specific self-reported outcomes in persons with lower-limb amputation using a non-microprocessor-controlled versus a microprocessor-controlled prosthetic knee

PURPOSE

To measure self-efficacy in a group of individuals who have undergone a lower-limb amputation and investigate the relationship between self-efficacy and prosthetic-specific outcomes including prosthetic use, mobility, amputation-related problems and global health. A second purpose was to examine if differences exist in outcomes based upon the type of prosthetic knee unit being used.

METHOD

Cross-sectional study using the General Self-Efficacy (GSE) Scale and the Questionnaire for Persons with a Transfemoral Amputation (Q-TFA). Forty-two individuals participated in the study. Twenty-three used a non-microprocessor-controlled prosthetic knee joint (non-MPK) and 19 used a microprocessor-controlled prosthetic knee joint (MPK).

RESULTS

The study sample had quite high GSE scores (32/40). GSE scores were significantly correlated to the Q-TFA prosthetic use, mobility and problem scores. High GSE scores were related to higher levels of prosthetic use, mobility, global scores and negatively related to problem score. No significant difference was observed between individuals using a non-MPK versus MPK joints.

CONCLUSIONS

Individuals with high self-efficacy used their prosthesis to a higher degree and high self-efficacy was related to higher level of mobility, global scores and fewer problems related to the amputation in individuals who have undergone a lower-limb amputation and were using a non-MPK or MPK knee. Implications for rehabilitation Perceived self-efficacy has has been shown to be related to quality of life, prosthetic mobility and capability as well as social activities in daily life. Prosthetic rehabilitation is primary focusing on physical improvement rather than psychological interventions. More attention should be directed towards the relationship between self-efficacy and prosthetic related outcomes during prosthetic rehabilitation after a lower-limb amputation.

Preliminary evaluation of a novel bladder-liner for facilitating residual limb fluid volume recovery without doffing

For people who wear a prosthetic limb, residual-limb fluid volume loss during the day may be problematic and detrimentally affect socket fit. The purpose of this research was to test the capability of a novel liner with adjustable bladders positioned within its wall to mitigate volume loss and facilitate limb fluid volume recovery and retention. Bioimpedance analysis was used to monitor fluid volume changes in the anterior and posterior residual limb of participants with transtibial amputation. Participants underwent six cycles of sitting for 90 s, standing for 90 s, and walking for 5 min with liquid within the bladder-liners. Between the third and fourth cycles, participants sat for 10 min with liquid left within the bladders (Liquid-In) or removed (Liquid-Out). Results showed that participants recovered more fluid volume during the 10 min of sitting with Liquid-Out than Liquid-In (p = 0.09 for anterior and p = 0.04 for posterior). However, those fluid volume recoveries were not well retained in the short term (after the fourth cycle) or the long term (after the sixth cycle). Physiologic differences between sessions, reflected in the rates of fluid volume change at the outset of the session, and excessive stiffness of the bladder-liners may have affected fluid volume retentions.

Targeted muscle reinnervation and advanced prosthetic arms

Targeted muscle reinnervation (TMR) is a surgical procedure used to improve the control of upper limb prostheses. Residual nerves from the amputated limb are transferred to reinnervate new muscle targets that have otherwise lost their function. These reinnervated muscles then serve as biological amplifiers of the amputated nerve motor signals, allowing for more intuitive control of advanced prosthetic arms. Here the authors provide a review of surgical techniques for TMR in patients with either transhumeral or shoulder disarticulation amputations. They also discuss how TMR may act synergistically with recent advances in prosthetic arm technologies to improve prosthesis controllability. Discussion of TMR and prosthesis control is presented in the context of a 41-year-old man with a left-side shoulder disarticulation and a right-side transhumeral amputation. This patient underwent bilateral TMR surgery and was fit with advanced pattern-recognition myoelectric prostheses.

Effects of prosthetic limb prescription on 3-year mortality among Veterans with lower-limb amputation

Our objective was to determine the relationship between receipt of a prescription for a prosthetic limb and 3 yr mortality postsurgery among Veterans with lower-limb amputation (LLA). We conducted a retrospective observational study that included 4,578 Veterans hospitalized for LLA and discharged in fiscal years 2003 and 2004. The outcome was time to all-cause mortality from the amputation surgical date up to the 3 yr anniversary of the surgical date. Of the Veterans with LLA, 1,300 (28.4%) received a prescription for a prosthetic limb within 1 yr after the surgical amputation. About 46% (n = 2,086) died within 3 yr of the surgical anniversary. Among those who received a prescription for a prosthetic limb, only 25.2% died within 3 yr of the surgical anniversary. After adjustment, Veterans who received a prescription for a prosthetic limb were less likely to die after the surgery than Veterans without a prescription, with a hazard ratio of 0.68 (95% confidence interval: 0.60-0.77). Findings demonstrated that Veterans with LLA who received a prescription for a prosthetic limb within 1 yr after the surgical amputation were less likely to die within 3 yr of the surgical amputation after controlling for patient-, treatment-, and facility-level characteristics.

Outcomes after 294 transtibial amputations with the posterior myocutaneous flap

The transtibial amputation is a common operation for which there is little agreement regarding which technique provides the most reliable and resilient outcomes. We performed a retrospective chart review of all transtibial amputations performed by a single surgeon between 2004 and 2011 using the posterior myocutaneous flap with triceps surae myodesis technique. A stepwise logistic regression analysis was performed to evaluate the association between independent variables and dependent outcome variables. A total of 270 patients with 294 transtibial amputations were identified. Ambulation data were available for 192 patients with a mean follow-up 18.4 months. This cohort had an overall ambulation rate of 75%, a 12% incidence of stump wounds, 24% operative revision rate and only 2% required conversion to a transfemoral amputation. The posterior myocutaneous flap provides durable and reliable soft tissue coverage in the setting of a transtibial amputation.