Residual Limb Research Articles

Development and pilot administration of the amputation-related pain and sensation assessment tool

Purpose To develop and administer an assessment tool for facilitating patient–clinician discussions regarding amputation-related pain and sensation. Materials and methods An assessment tool was developed to measure the impact of different types of amputation-related pain and sensation on a patient’s life. The tool first provides patients with written descriptions and images of three common types of amputation-related pain or sensations: residual limb pain, phantom limb sensation, and phantom limb pain. The tool then asks them to rate the frequency, intensity, and interference of each experience. Participants were also asked to provide qualitative descriptions of these experiences. Results Fifty Veterans with lower limb amputation participated in the study. In the past month, 74% reported experiencing residual limb pain, 76% reported phantom limb sensation, and 84% reported phantom limb pain, with 52% reporting all three. Participants’ descriptions of some experiences were distinct, while others (e.g., “tingling”) were common between experiences. Phantom limb pain had the most varied descriptions. Conclusions The amputation-related pain and sensation assessment tool can be used to identify and measure the effects of different experiences on patients’ lives, thereby improving the specificity of diagnosis and informing clinical treatment recommendations. Further development of this tool should include evaluating its psychometric properties.

Fillet flap transfer as alternative to conventional lower limb amputation

The fitting of a prosthesis after lower limb amputation is associated with several challenges. Skeletal stump-prosthesis interfaces and selective nerve transfer can partially overcome these but are also associated with new impairments that emphasize the necessity of innovative approaches. The concept of so-called spare part surgery with the use of fillet flaps could play an important role in this respect. An overview of the classical prosthesis-associated discomforts, advantages and disadvantages of treatment strategies and presentation of alternative surgical concepts. A selective literature search was carried out considering the experiences of the authors and perspectives with respect to the advantages and disadvantages of the surgical treatment options. Furthermore, aclinical case is presented. The transfer of the sole of the foot as afillet flap to the weight-bearing region of the amputation stump offers anumber of benefits, such as creating afully weight-bearing stump, prevention of neuralgia, preserved sensation and conservation of the body image. As long as the calcaneal region is not impaired, this technique can be performed in amputations below as well as above the knee. The question of whether parts of the bone should be included in the transfer must be individually evaluated for each patient. This approach enables optimization of the residual limb stump for the subsequent fitting of a prosthesis for the patient.

Frequency and Localization of Neuromas in Transtibial Residual Limbs

ObjectiveTo describe the frequency and localization of neuromas in residual limbs of individuals with transtibial amputation using ultrasound imaging. DesignCross-sectional study. SettingRehabilitation center research laboratory. ParticipantsAdults who have lived with a transtibial amputation for >12 months were recruited for this study. Participants were included regardless of the presence or absence of residual limb neuropathic pain. Twenty-three participants (24 transtibial residual limbs) with and without residual limb neuropathic pain were enrolled. The etiology of amputation of most participants was peripheral vascular disease and diabetes. InterventionA comprehensive history was collected and a musculoskeletal ultrasound assessment for the presence and location of neuromas in their residual limb was conducted. During the ultrasound evaluation, a sonopalpation Tinel test was performed by applying pressure on each neuroma with the probe. Main Outcome MeasuresNumber of neuromas and their localization in each residual limb examined. ResultsA total of 31 neuromas in the 24 transtibial residual limbs were identified by ultrasound imaging. The average number of neuromas per residual limb was 1.3. All the major peripheral nerves studied could present neuromas, with a predominance of the superficial fibular nerve within our sample. Thirty-five percent of all the neuromas were described as painful. ConclusionsThe presence of terminal neuromas on surgically sectioned nerves in transtibial residual limbs is frequent. Seventy-nine percent of participants had at least one neuroma. Ultrasound imaging is clinically useful to identify neuromas. The evaluator can easily communicate with the patient to diagnose symptomatic neuromas.

A NEW TEMPORARY TRAINING PROSTHESIS FOR PEOPLE WITH TRANSTIBIAL AMPUTATION: A TECHNICAL NOTE

BACKGROUND: While waiting to receive a prosthesis, individuals with amputations could benefit from using a temporary training prosthesis to expedite the rehabilitation process and prepare them for subsequent walking with their prosthesis. OBJECTIVES: To design and build a temporary training prosthesis for people with a transtibial amputation. METHODOLOGY: Various temporary training prostheses were designed and simulated using SolidWorks software, followed by fabricating and testing multiple prototypes. Initial tests were conducted on five able bodied subjects without amputation to evaluate comfort, ensure the prototype functioned as intended, and to refine the design. The final prototype design had no weight-bearing on the residual limb end and required the person to wear a shrinker or silicone liner. FINDINGS: SolidWorks simulations showed that the device could tolerate up to 200 kg load. Subjective feedback indicated that body weight is primarily supported by the thigh section, while partially utilizing the patellar tendon and tibial flares. The thigh section can be shifted 5 cm up or down and 2.5 cm to the front or back from the knee joint center (to enhance knee stability or function). Additionally, the thigh angle can be adjusted to 0, 5, 10, or 15 degrees to accommodate hip flexion contracture. The shank section width is adjustable and can be shifted up or down based on the residual limb shape. All five able-bodied participants successfully walked with the non-amputee version of the temporary prosthesis prototype and the device withstood walking, sitting, and standing loads. CONCLUSION: An adjustable temporary training prosthesis was successfully designed, and pilot tested by five able-bodied individuals. Future testing will involve five experienced prosthetic users before conducting trials with individuals with a new transtibial amputation. Layman's Abstract A novel temporary training prosthesis was developed for individuals with new transtibial amputations while they await the healing of their residual limb and the receipt of a prosthesis. Utilizing SolidWorks computer-aided design software, various designs were explored, and rigorous testing was conducted to ensure durability and functionality. Adjustable features were incorporated to accommodate different body shapes and sizes. Initial testing on five people without amputations confirmed device effectiveness in supporting walking, sitting, and standing. Next, performance will be assessed on five experienced prosthetic users before proceeding to trials with individuals with a new transtibial amputation. This temporary prosthesis aims to expedite rehabilitation, enabling people to regain mobility and independence more efficiently. Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/43034/32865 How To Cite: Gholizadeh H, Baddour N, Dudek N, Lemaire E.D. A new temporary training prosthesis for people with transtibial amputation: A technical note. Canadian Prosthetics & Orthotics Journal. 2024; Volume 7, Issue 1, No.2. https://doi.org/10.33137/cpoj.v7i1.43034 Corresponding Author: Hossein Gholizadeh, PhD, CP (Canada)Department of Mechanical Engineering, University of Ottawa, Ottawa, Canada.E-Mails: hgholizadeh@uottawa.ca, gholizadeh87@yahoo.comORCID ID: https://orcid.org/0000-0001-5847-7985

Neuropathic pain after major limb amputation: a cross-sectional study

Background & Objective: Residual limb pain (RLP) and phantom pain can arise following amputation and may require additional treatment or surgery. This study aimed to determine the prevalence of neuropathic RLP following limb amputation and identify prognostic factors for the development of neuropathic RLP. Methods: A cross-sectional study was performed of patients who underwent upper or lower extremity amputation between 1990 and 2021 with a minimum of twelve months follow-up. The primary outcome was the prevalence of neuropathic RLP, defined as a 0-10 NRS pain score in the residual limb of ≥4, in combination with a score ≥4 on the short form DN4 questionnaire (s-DN4), validated for discriminating between nociceptive and neuropathic pain. The secondary outcome was quality of life for amputees with and without (neuropathic) RLP. A multivariable linear regression model was used to identify prognostic factors for neuropathic RLP development. Results: A total of 121 patients were included: 87 with lower extremity amputations, 29 with upper extremity amputations, and 5 with both. Neuropathic RLP was experienced by 21.5%, while 10.7% reported non-neuropathic RLP. Smoking status and Complex Regional Pain Syndrome as indication for limb amputation were associated with more severe neuropathic pain symptoms. Patients experiencing neuropathic RLP reported a significantly lower quality of life compared to patients without neuropathic RLP. Conclusions: This study demonstrates that neuropathic RLP is common after limb amputation and impacts daily functioning. The absence of numerous manageable prognostic factors associated with neuropathic pain development emphasizes the importance of the consideration of prophylactic interventions at the time of amputation.

Targeted Muscle Reinnervation

Background Targeted muscle reinnervation (TMR) has demonstrated efficacy in reducing neuroma and chronic pain. In this article, we investigated postoperative outcomes in our patient cohort, with a focus on the role of nonmodifiable factors such as patient age and gender. Methods Patients who had extremity TMR from April 2018 to October 2022 were reviewed. Outcomes of interest included patient age, gender, cause and type of amputation, delayed versus immediate TMR, as well as postoperative improvement in pain as assessed by numerical rating score (NRS). Results A total of 40 patients underwent TMR on 47 limbs. Mean age was 46.2 ± 17.0 years. Delayed TMR (27, 57.4%) was most commonly performed, followed by immediate and delayed-immediate at 11 (23.4%) and 9 (19.1%), respectively. Amputation level was most commonly above-knee in 20 (42.6%) patients, followed by below-knee (12, 25.5%), transhumeral (8, 17.0%), transradial (6, 12.8%), and shoulder (1, 2.1%). The median time interval between amputation and TMR was 12 months. The median preoperative NRS assessing residual limb pain (RLP) for patients who underwent delayed TMR was 10. The median postoperative NRS assessing RLP for all patients was 0 (interquartile range25–75: 0–5) and significantly improved compared with preoperative NRS (P < 0.001). At the last follow-up for limbs that had delayed and delayed-immediate TMR (n = 36), 33 (91.7%) limbs had more than 50% resolution of RLP. There was a significant difference in median postoperative NRS by gender (4 in men and 0 in women) (P < 0.05). Postoperative median NRS also favored younger patients (0, <50 years compared with 4.5, >50 years) (P < 0.05). Multiple linear regression analysis showed that, of different variables analyzed, only male gender and older age were predictive of poorer postoperative outcomes. Conclusion TMR showed high efficacy in our cohort, with improved short-term outcomes in women and younger patients.

Dynamic gait stability and stability symmetry for people with transfemoral amputation: A case-series of 19 individuals with bone-anchored limbs

For some individuals with severe socket-related problems, prosthesis osseointegration directly connects a prosthesis to the residual limb creating a bone-anchored limb (BAL). We compared dynamic gait stability and between-limb stability symmetry, as measured by the Margin of Stability (MoS) and the Normalized Symmetry Index (NSI), for people with unilateral transfemoral amputation before and one-year after BAL implantation. The MoS provides a mechanical construct to assess dynamic gait stability and infer center of mass and limb control by relating the center of mass and velocity to the base of support. Before and one-year after BAL implantation, 19 participants walked overground at self-selected speeds. We quantified dynamic gait stability anteriorly and laterally at foot strike and at the minimum lateral MoS value. After implantation, we observed decreased lateral MoS at foot strike for the amputated (MoS mean(SD) %height; pre: 6.6(2.3), post: 5.9(1.3), d = 0.45) and intact limb (pre: 6.2(1.2), post: 5.8(1.0), d = 0.38) and increased between-limb MoS symmetry at foot strike (NSI mean(SD) %; anterior–pre: 10.3(7.3), post: 8.4(3.6), d = 0.23; lateral–pre: 18.8(12.4), post: 12.4(4.9), d = 0.47) and at minimum lateral stability (pre: 28.1(18.1), post: 19.2(6.8), d = 0.50). Center of mass control using a BAL resulted in dynamic gait stability more similar between limbs and may have reduced the adoption of functional asymmetries. We suggest that improved between-limb MoS symmetry after BAL implantation is likely due to subtle changes in individual limb MoS values at self-selected walking speeds resulting in an overall positive impact on fall risk through improved center of mass and prosthetic limb control.

Immersive virtual reality applied to the rehabilitation of patients with lower limb amputation: a small randomized controlled trial for feasibility study

Limb amputation significantly impacts the socioeconomic and health aspects of affected individuals, with clinical issues such as phantom limb pain (PLP), phantom limb telescopy (PLT), residual limb pain (RLP), and decreased balance necessitating improved treatments. Although interventions utilizing Immersive Virtual Reality (IVR) have been explored, conducting Randomized Clinical Trials (RCT) within this population presents challenges. This study serves as a feasibility study derived from a small RCT, aiming to investigate the effects of an IVR intervention protocol on individuals with lower limb amputation (LLA) while addressing methodological challenges and exploring alternative study designs. Participants were randomly assigned to either the Control Group (CG), receiving no intervention, or the Intervention Group (IG), undergoing 16 IVR sessions over 8 weeks, with twenty-one participants completing the protocol. Sessions involved observing physical exercises via a head-mounted display. All participants were assessed for pain and balance pre- and post-intervention. IG participants were also evaluated for pain, sense of presence in the virtual environment, and cybersickness on intervention days. Results indicated a significant negative correlation between RLP and time since amputation in the Intervention Group. Analysis of results between IG and CG post-assessment suggests potential benefits of IVR in improving balance and reducing PLT. Despite challenges related to sample size and participant retention, multicenter collaborations and home-based interventions are proposed to mitigate these limitations. This feasibility study lays a foundation for future research aiming to optimize VR interventions for improved outcomes in patients with LLA.

Assessment of self-esteem and quality of life in patients with transtibial amputations using an exoskeletal prosthesis.

Lower limb amputation can have profound physical, psychological, and social effects on individuals. Assistive aids like prosthetic lower limbs can help an individual regain mobility and thereby affect their self-esteem and quality of life. To assess self-esteem and quality of life in patients with transtibial amputations who are using a transtibial prosthesis and explore the association between sociodemographic and amputation-related factors with self-esteem and prosthesis-related quality of life measures. A cross-sectional study. An orthotics and prosthetics center (Bhagwan Mahaveer Viklang Sahayata Samiti) in Jaipur, Rajasthan. Patients with transtibial amputations using exoskeletal prostheses between July and September 2022, in Jaipur, Rajasthan. The study used Rosenberg self-esteem questionnaire and Prosthesis Evaluation Questionnaire (PEQ) for self-esteem and quality of life assessment, respectively. Descriptive analysis was used to present the demographic details, and nonparametric tests examined the relationship between PEQ dimensions and sociodemographic variables. The study included 138 participants, primarily <40 years old (45.7%) and mostly engaged in high-activity occupations. Self-esteem mean score (SD) was 19.9 (3.9), with 89.1% exhibiting normal self-esteem. Prosthesis-related quality of life, showed high satisfaction across various domains, including ambulation, appearance, frustration, perceived response, residual limb health, social burden, sounds, utility, and well-being. No significant associations were found between sociodemographic factors, amputation-related variables, and self-esteem. However, PEQ scales showed associations with gender, age, occupation, type of amputation, and years of prosthesis use. These results highlight the potential advantages of exoskeletal prostheses in improving the standard of living for people with transtibial amputations. Further research is essential to develop targeted interventions for improving their overall quality of life.

The effect of medium-tension bandage and stump stocking on residual limb maturation in earthquake survivors.

Residual limb maturation is a crucial stage in postamputation care. It was aimed to examine the effect of medium tension bandages and stump stockings on postamputation stump maturation in patients who underwent lower extremity amputations. In this prospective observational study, patients who were earthquake survivors and had undergone emergency amputation of their lower extremities were included. Medium-tension elastic bandage or personalized stump stockings were used for stump maturation. Residual limb volume was measured once a week for 3 weeks. The study included 23 patients and 29 amputated limbs. Because of the larger stump volume of transfemoral amputations and the higher number of these patients in the stocking group ( p < 0.001), the stump volume differed across groups before and during the follow-up ( p < 0.001). There was no difference in mean volumetric measurement between the bandage and stocking groups over time ( p = 0.272). Although the group interaction was significant (p < 0.001), the group × time interaction was not ( p = 0.306). Medium-tension bandages and stump stockings had a similar effect on postamputation stump maturation in patients with lower extremity amputations. So, depending on the patient's and physician's preferences, both procedures can be used for stump maturation.

Rehabilitative outcomes with preparatory suction prostheses following traumatic Gritti-Stokes amputation: A case series.

Gritti-Stokes amputation (GSA) is a knee disarticulation variant, where the femur is transected at the level of the epicondyle and the patella is fixated to the distal end. GSA results in a long residual limb with little postoperative swelling and less potential for muscular atrophy, so stable limb volume may allow the use of seal-in suction for suspension for preparatory prostheses. The purpose of this case series was to report on the efficacy of seal-in suction preparatory prostheses for 2 adults with traumatic GSA. Between October and December of 2021, 2 participants with unilateral traumatic Gritti-Stokes amputation, who had received seal-in suction suspension for their preparatory prostheses, were recruited. Information was extracted from medical charts regarding prosthetic care and mobility at preparatory and definitive prosthesis evaluation, and participants underwent standardized measurement of their residual limb and prosthesis. Duration of preparatory prosthesis use was >6 months; neither participant reported loss of suspension nor significant complications with socket fit. Participant 1 required socket replacement because of residual limb pain secondary to osteophyte formation, and Participant 2 required component replacement because of weight gain. At definitive prosthesis evaluations, both participants were unlimited community ambulators; both successfully returned to work before provision of their definitive prostheses. Results indicate that seal-in suction suspension may be viable for preparatory prostheses among adults with traumatic GSA, but knee center height discrepancies persist. GSA may yield highly functional outcomes for adults with traumatic amputation. Further research is required to substantiate these findings.

Patient Outcomes in a Novel Osseointegrated Device for Transfemoral Amputation: a case series

Background Socket suspension (SS) prosthetics are the current standard for transfemoral amputee prosthetic management. The SS systems have been shown to be inefficient in energy transfer, leading to gait alteration, wear discomfort, and skin complications. Many studies have shown osseointegrated (OI) devices are not associated with these problems and offer many benefits. Purpose Through this report the authors will describe surgical outcomes following transfemoral amputation (TFA) surgery using a novel OI device. Methods Patients with problematic TFA were identified from 2013 to 2018 were treated with a novel OI system. Candidate TFA patients identified through record review as part of an IRB authorized retrospective study. The study group all had the following characteristics: (1)No diabetes, (2)no peripheral vascular disease, and (3)mature healed TFA. All study subjects had attempted use of SS and had failed for many reasons related to the skin to socket interface. The outcomes measured recorded included: (1)Q-TFA Scores, (2)SF-36 Score, (3)time coupled per day, (4)resolution of back pain, (5)residual limb pain, and (6)overall satisfaction. Radiographs of implanted stems were reviewed for evidence of loosening or bone on growth. Results A group of TFA patients (11) had been treated with the OI system and agreed for follow up evaluation. Mean age 52 (37-73) years at the time of OI stage I surgery, with a mean time of 9 (3-20) years post amputation to implantation of the OI system. Original indications for the amputation included: 1 chronic osteomyelitis, 1 neoplasm, and 9 traumatic. Mean time to from TFA to OI was 73 months (2- 216). All patients reported a reduction or complete resolution of back pain after OI. Ambulatory/device coupling status reported was mean 12 hours/day. Average Q-TFA Prosthetic use score 66.1, Prosthetic mobility score, 60.2, Problem score 18.2, and Global score 72. Average SF-36 PCS 56.2 and average MCS 70.0. Radiographs reviewed all showed 4 to 6mm of distal circumferential bone reabsorption with robust bone on growth in the diaphysis of the implanted femurs. Conclusion Early data on the effectiveness and safety of the custom Patriot™ OI device is favorable. Future study evaluating long-term device survivorship and patient reported outcomes is warranted. Bone remodeling post implantation and coupling showed positive effects of the system. This study found the custom OI device to be safe and effective in the management of TFA in patients with controlled indications.

P34 Evaluating the adaptation of the amputee skin owing to prosthesis use: a study using in vivo Raman spectroscopy

Abstract Introduction and aims Lower limb prosthesis has proven to be an extremely successful intervention for amputees. However, to achieve adequate function, the device places significant friction and load on the skin, which leads to substantial skin breakdown. Current rehabilitation practices require skin to be ‘trained’ to perform a load-bearing role. Despite this, there are very high injury statistics for skin on the residual limb in the literature, we hypothesize that rehabilitation practices to adapt amputee skin are limited. Methods To interrogate this, we used in vivo Raman spectroscopy to evaluate the lower limbs of 13 unilateral lower limb amputees. This enabled us to assess how key constituents of the stratum corneum (SC) such as natural moisturizing factor (NMF), water and lipid content vary with depth. We also analysed sebum content to quantify cytokines present and performed mechanical characterization of the lower limb to investigate stiffness and friction. Results We found that the Raman spectra of the amputated limb show reduced NMF, lipid content and water content at the top of the SC when compared with the intact limb (P &amp;lt; 0.05). In addition, we found that amputee skin contains higher levels of inflammatory cytokines compared with control skin. We also recorded that skin on the residuum is four times softer than the intact limb, while friction is much higher at 0.5 on the residuum skin, compared with 0.3 on the intact limb. Conclusions Here, we show the adaptations of amputee skin in response to rehabilitation to be minimal. Contrary to the dogma that rehabilitation trains skin to bear load, we found that skin barrier function in amputee skin is impaired, as indicated by altered water and lipid profile in addition to higher baseline inflammation.

The significance of frontal plane static alignment in anticipating dynamic knee moment among transtibial prosthesis users: A cross-sectional study

BackgroundIn the process of transtibial prosthetic fitting, alignment is the process of positioning the prosthetic foot relative to the residual limb. Changes in frontal plane alignment can impact knee moments during walking, which can either cause or, when aligned properly, prevent injuries. However, clinical evaluation of dynamic knee moments is challenging, limiting prosthetists' insights into dynamic joint loading. Typically, knee joint loading is assessed in static stance using the knee moment arm as a proxy for subsequent dynamic alignment. It remains uncertain if static alignment accurately represents actual dynamics during walking. Research questionIs the frontal knee moment arm in stance predictive for the knee moment arm and external knee adduction moment during gait in transtibial bone-anchored prosthesis users? MethodsIn this cross-sectional study, twenty-seven unilateral transtibial bone-anchored prosthesis users underwent data acquisition on the M-Gait instrumented treadmill. Static and dynamic measurements were conducted, and knee moment arm and external knee adduction moment were calculated. Pearson's correlation and linear regression analyses were performed to examine relationships between static and dynamic knee moment arms and external knee adduction moments. ResultsThe static knee moment arm showed significant associations with dynamic knee moment arm at the ground reaction force peaks (First: r=0.60, r2=35%, p<0.001; Second: r=0.62, r2=38%, p=0.001) and knee adduction moment (First: r=0.42, r2=17%, p=0.030; Second: r=0.59, r2=35%, p=0.001). A 1 mm between-subject difference in static knee moment arm corresponded, on average, with a 0.9% difference in knee adduction moment at the first peak and a 1.5% difference at the second peak of the ground reaction force. SignificanceWhile static alignment is important to optimize adduction moments during stance it may only partly mitigate excessive moments during gait. The fair correlation and limited percentage of explained variance underscores the importance of dynamic alignment in optimizing the body's dynamic load during walking.

An adaptive prosthetic socket for people with transtibial amputation

It is essential that people with limb amputation maintain proper prosthetic socket fit to prevent injury. Monitoring and adjusting socket fit, for example by removing the prosthesis to add prosthetic socks, is burdensome and can adversely affect users’ function and quality-of-life. This study presents results from take-home testing of a motor-driven adaptive socket that automatically adjusted socket size during walking. A socket fit metric was calculated from inductive sensor measurements of the distance between the elastomeric liner surrounding the residual limb and the socket’s inner surface. A proportional-integral controller was implemented to adjust socket size. When tested on 12 participants with transtibial amputation, the controller was active a mean of 68% of the walking time. In general, participants who walked more than 20 min/day demonstrated greater activity, less doff time, and fewer manual socket size adjustments for the adaptive socket compared with a locked non-adjustable socket and a motor-driven socket that participants adjusted with a smartphone application. Nine of 12 participants reported that they would use a motor-driven adjustable socket if it were available as it would limit their socket fit issues. The size and weight of the adaptive socket were considered the most important variables to improve.

Gait Analysis of Knee Joint Walking Based on Image Processing.

With the in-depth development of assistive treatment devices, the application of artificial knee joints in the rehabilitation of amputees is becoming increasingly mature. The length of residual limbs and muscle strength of patients have individual differences, and the current artificial knee joint lacks certain adaptability in the personalized rehabilitation of patients. In order to deeply analyze the impact of different types of artificial knee joints on the walking function of unilateral thigh amputees, improve the performance of artificial knee joints, and enhance the rehabilitation effect of patients, this article combines image processing technology to conduct in-depth research on the walking gait analysis of different artificial knee joints of unilateral thigh amputees. This article divides patients into two groups: the experimental group consists of patients with single leg amputation, and the control group consists of patients with different prostheses. An image processing system is constructed using universal video and computer hardware, and relevant technologies are used to recognize and track landmarks; Furthermore, image processing technology was used to analyze the gait of different groups of patients. Finally, by analyzing the different psychological reactions of amputees, corresponding treatment plans were developed. Different prostheses worn by amputees have brought varying degrees of convenience to life to a certain extent. The walking stability of wearing hydraulic single axis prosthetic joints is only 79%, and the gait elegance is relatively low. The walking stability of wearing intelligent artificial joints is as high as 96%. Elegant gait is basically in good condition. Image processing technology helps doctors and rehabilitation practitioners better understand the gait characteristics and rehabilitation progress of patients wearing different artificial knee joints, providing objective basis for personalized rehabilitation of patients.

Complicaciones médico-quirúrgicas y su impacto en el retorno laboral durante el seguimiento de pacientes con amputación mayor de extremidades inferiores en el Hospital del Trabajador de Santiago (HTS)

IntroductionThe presence of different complications whilst follow-up amputee patients reaches 10-80%. The main objective of this research is to assess the impact of these in the return-to-work of lower-limb traumatic amputation cases. Materials and methodsA retrospective cohort research was carried out. Clinic-demographic variables information was recollected in order to assess its linkage to different medical-surgical complications and functional outcomes. Survival curves were created to evaluate the return-to-work of patients with and without complications. ResultsA total of 46 patients, on average aged 45.7 years old (91.3% men, 71.7% without comorbidities), were included on this research. The most frequent level of amputation was transtibial (65.2%). Residual limb pain, phantom pain, dermatological-infectious complications and painful neuroma were registered in 80.4%, 58.7%, 50% y 30.4% of the cases respectively. Half of the patients had returned to their workplace after 2years of post-surgical follow-up. The return-to-work rates were significantly lower in patients suffering from residual limb pain (p=0.0083) and from painful neuroma (p=0.0051). ConclusionComplications are frequent during traumatic-amputee patients’ follow-up and, some of them, may impact on the return-to-work rate.

An enhancement of the Genium™ microprocessor-controlled knee improves safety and different aspects of the perceived prosthetic experience for unilateral and bilateral users.

Bilateral microprocessor-controlled prosthetic knee (MPK) users have unique needs in traversing environmental barriers compared to unilateral users. An enhancement to the Genium™/Genium X3™ MPK which included an updated ruleset, hydraulics, and new bilateral parameter presets was made to improve safety while stumbling and the smoothness of gait for all users while also improving the experience of bilateral users. The purpose of the study was to evaluate the effectiveness of the enhancements in a sample with unilateral and bilateral amputation. A convenience sample of MPK users was recruited from two sites in the USA in two phases. Assessments included the L-Test of Functional Mobility, Activity-specific Balance Confidence Scale, Prosthetic Limb User Survey of Mobility, a study-specific questionnaire, and the Comparative Activities of Daily Living (ADL) Questionnaire. Statistical significance of extracted data was tested with the Wilcoxon Rank-Sum Test for independent data and Wilcoxon Signed-Rank for paired data with an a priori significance level of p < 0.05. Unilateral subjects were age-matched to the group of bilateral subjects for between-groups and within-groups analyses. Twenty-six subjects (n = 26) were enrolled. Stumble frequency reduced 85% from 16.0 ± 39.7 to 2.4 ± 2.3 (p = 0.008) between baseline and final assessment overall. The bilateral group reported 50% (p = 0.009) and 57% (p = 0.009) greater relative improvement in patient-reported ease and safety, respectively, of completing ADLs compared to the unilateral group. The unilateral group reported residual limb pain and low back pain reduced from 2.3 to 1.4 (p = 0.020) and 3.8 to 1.8 (p = 0.027), respectively, whereas the bilateral group did not. Substantial reductions in stumbles, residual limb pain, and back pain were shown overall. These reductions were driven by the unilateral group who also showed improvements in comfort, exertion, and concentration while walking. The enhancements to the knee likely reduced some gait asymmetry for unilateral users. Improvements in patient-reported ease and safety of completing ADLs were shown overall and were driven by the bilateral group. This study shows further improvement in patient experience is achievable through innovation in MPK technology even for patients who appear to be functioning well.

Prosthetic Limb Attachment via Electromagnetic Attraction Through a Closed Skin Envelope.

Current socket-based methods of prosthetic limb attachment are responsible for many of the dominant problems reported by persons with amputation. In this work, we introduce a new paradigm for attachment via electromagnetic attraction between a bone-anchored ferromagnetic implant and an external electromagnet. Our objective was to develop a design framework for electromagnetic attachment, and to evaluate this framework in the context of transfemoral amputation. We first used inverse dynamics to calculate the forces required to suspend a knee-ankle-foot prosthesis during gait. We then conducted cadaveric dissections to inform implant geometry and design a surgical methodology for covering the implant. We also developed an in silico framework to investigate how electromagnet design affects system performance. Simulations were validated against benchtop testing of a custom-built electromagnet. The physical electromagnet matched simulations, with a root-mean-square percentage error of 4.2% between measured and predicted forces. Using this electromagnet, we estimate that suspension of a prosthesis during gait would require 33 W of average power. After 200 and 1000 steps of simulated walking, the temperature at the skin would increase 2.3 °C and 15.4 °C relative to ambient, respectively. Our design framework produced an implant and electromagnet that could feasibly suspend a knee-ankle-foot prosthesis during short walking bouts. Future work will focus on optimization of this system to reduce heating during longer bouts. This work demonstrates the initial feasibility of an electromagnetic prosthetic attachment paradigm that has the potential to increase comfort and improve residual limb health for persons with amputation.

Acute versus non-acute targeted muscle reinnervation for pain control following major limb amputation: A comparative study

BackgroundTargeted muscle reinnervation (TMR) has been shown to reduce phantom limb pain (PLP) and residual limb pain (RLP) after major limb amputation. However, the effect of the timing of surgery on pain control and quality of life outcomes is controversial. We conducted a retrospective study to compare the outcomes of acute TMR for pain prevention with non-acute TMR for the treatment of established pain. MethodsAll patients treated with TMR in our institution between January 2018 and December 2021 were evaluated at 6, 12, 18 and 24 months post-operatively. Pain intensity and quality of life outcomes were assessed using the Brief Pain Inventory (Pain Severity and Pain Interference scales) and Pain Catastrophizing Scale. Outcomes were compared between acute and non-acute TMR using the Wilcoxon ranked-sum test or Fisher’s exact test as appropriate. Multilevel mixed-effects linear regression was used to account for repeat measures and potential pain confounders. ResultsThirty-two patients with 38 major limb amputations were included. Acute TMR patients reported significantly lower RLP and PLP scores, pain interference and pain catastrophisation at all time points (p < 0.05). Acute TMR was significantly associated with lower pain severity and pain interference in a linear mixed-effects model accounting for patient age, gender, amputation indication, amputation site, time post-TMR and repeated surveys (p < 0.05). There was no significant difference in the complication rate (p = 0.51). ConclusionAcute TMR was associated with clinically and statistically significant pain outcomes that were better than that in non-acute TMR. This suggests that TMR should be performed with preventative intent, when possible, as part of a multidisciplinary approach to pain management, rather than deferred until the development of chronic pain.