Residual Limb Research Articles

WOUND MANAGEMENT, HEALING, AND EARLY PROSTHETIC REHABILITATION: PART 1 - A SCOPING REVIEW OF HEALING AND NON-HEALING DEFINITIONS

BACKGROUND: Following lower limb amputation, timely prosthetic fitting enhances mobility and quality of life. However, inconsistent definitions of surgical site healing complicate prosthesis readiness assessment and highlight the need for objective wound management measures. OBJECTIVE: This review aimed to compile definitions of healing and non-healing provided in the literature investigating biomarkers of healing of the tissues and structures found in the residual limbs of adults with amputation. METHODOLOGY: A scoping review was conducted following JBI and PRISMA-ScR guidance. Searches using “biomarkers,” “wound healing,” and “amputation” were performed on May 6, 2023, on Web of Science, Ovid MEDLINE, Ovid Embase, Scopus, Cochrane, PubMed, and CINAHL databases. Inclusion criteria were: 1) References to biomarkers and healing; 2) Residuum tissue healing; 3) Clear methodology with ethical approval; 4) Published from 2017 onwards. Articles were assessed for quality (QualSyst tool) and evidence level (JBI system). FINDINGS: Of 3,306 articles screened, 219 met the inclusion criteria and are reviewed in this article, with 77% rated strong quality. 43% of all included sources did not define healing, while the remainder used specific criteria including epithelialization (14%), wound size reduction (28%), gradings scales (3%), scarring (1%), absence of wound complications (2%), hydroxyproline levels (0.5%), no amputation (0.5%), or neovascularization (0.5%). 84% of included sources did not provide definitions of non-healing. Studies defining non-healing used criteria like wound complications (4%), the need for operative interventions (4%), or lack of wound size reduction (1%). For 10% of included sources, healing and non-healing definitions were considered not applicable given the research content. Total percentages exceed 100% for both healing and non-healing definitions because some sources used two definition classifications, such as epithelialization and wound size reduction. The findings indicate a lack of standardized definitions irrespective of study type. CONCLUSION: This review reveals significant gaps in current definitions of healing and non-healing, often based on superficial assessments that overlook deeper tissue healing and mechanical properties essential for prosthesis use. It emphasizes the need for comprehensive definitions incorporating biomarkers and psychosocial factors to improve wound management and post-amputation recovery. Layman's Abstract After a lower limb amputation, early prosthetic fitting can significantly improve quality of life. However, different definitions of surgical site healing make deciding when a prosthetic can be used difficult. This scoping review collected and compared definitions of healing and non-healing found in research about biological markers (biomarkers) that are used for tracking residual limb healing. On May 6, 2023, searches were conducted using terms like “biomarkers,” “wound healing,” and “amputation” across several databases. Studies were included if they discussed biomarkers, focused on residual limb healing, had clear methods and ethical approval, and were published during or after 2017. Of 3,306 articles screened, 219 met the criteria, with 77% rated as high quality. 43% of the included sources did not define healing. Definitions provided included new skin growth (14%), reduction in wound size (28%), grading scales (3%), scarring (1%), no complications (2%), hydroxyproline levels (0.5%), no need for amputation (0.5%), or new blood vessel formation (0.5%). 84% of sources did not define non-healing, with the remainder based on healing complications (4%), the need for more surgery (4%), or no reduction in wound size (1%). In 10% of included sources healing and non-healing definitions were considered not relevant to their research. Total percentages for healing and non-healing definitions exceeds 100% because some sources used two definitions, for example, new skin growth and reduction in wound size. Overall, the review shows gaps in definitions, many of which are too basic and ignore deeper tissue healing and factors needed for prosthetic use. More thorough definitions that include the physical, mental, and social sides of healing are needed to improve recovery. Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/43715/33312 How To Cite: Williams-Reid H, Johannesson A, Buis A. Wound management, healing, and early prosthetic rehabilitation: Part 1 - A scoping review of healing and non-healing definitions. Canadian Prosthetics & Orthotics Journal. 2024; Volume 7, Issue 2, No.1. https://doi.org/10.33137/cpoj.v7i2.43715 Corresponding Author: Professor Arjan Buis, PhDDepartment of Biomedical Engineering, Faculty of Engineering, University of Strathclyde, Glasgow, Scotland.E-Mail: arjan.buis@strath.ac.ukORCID ID: https://orcid.org/0000-0003-3947-293X

Nonfinancial Barriers to Prosthetic Use Following Upper-Limb Amputation: A Prospective Observational Study in India

ABSTRACT Introduction Upper-limb traumatic amputation is a common and poorly managed situation. Despite the huge burden, no study from the developing countries has evaluated rates of prosthesis acceptance and reasons for rejecting prostheses. Materials and Methods This was a longitudinal prospective observational study with a consecutive sampling technique. Participants were assessed after a period of 6 months of isolated upper-limb amputation. Patients were evaluated for reasons of nonfitment of upper-limb prosthesis despite their willingness to be fitted with an appropriate prosthesis. We conducted semistructured interviews to identify the potential hindrances. Results A total of 44 patients were recruited, out of which 38 did not get the prosthesis. A total of 57.8% reported a nonfinancial reason for prosthesis nonfitment. Nonfinancial is further classified into medical and nonmedical categories as per verbatim remarks by the patient. Among the nonmedical reasons, the most common reason was apprehension toward the use of the prosthesis, followed by satisfaction without the prosthesis and the weight of the prosthesis. In terms of medical reasons, the most common reason was persistent phantom limb pain, followed by residual limb infection. Conclusions Identification of “potentially correctable” hindrances to prosthesis acceptance is an essential step in the rehabilitation of persons with limb loss. All efforts should be made toward these hindrances so that persons with limb difference can be better rehabilitated. Clinical Relevance Given that some persons with limb difference need to be fitted with prostheses for optimal rehabilitation and to return as an able contributor to society, the identification of hindrances to prosthesis fitting is imperative to make further inroads toward improving prosthesis acceptance rate.

Comparison of static balance and pressure distribution in individuals with unilateral lower limb amputation: The role of barefoot, heel support, and vision.

In some cultures, shoes are not worn indoors. Prosthesis use barefoot can lead to pressure injuries and loss of balance due to abnormal residual limb loading. This study aimed to compare the effect of wearing standard alignment prostheses using barefoot at home and visual alteration on static balance and pressure distribution in individuals with unilateral transfemoral amputations (TFAs) or transtibial amputations (TTAs). Prospective parallel experimental study. Participants with unilateral TTAs (n = 44) and TFAs (n = 37) were included. Balance and load distribution were assessed using MatScan pressure platforms, both with a heel (3 × 2 cm2 area; 1.8 cm height) support (the use of shoes with a heel is mimicked) and barefoot. Balance parameters were disrupted in all groups when eyes closed position (p < 0.05). Using heels reduced anterior-posterior and medial-lateral sway in TTA group during eyes closed (p < 0.05). When standing barefoot with the eye open position, TFA group had more load on the rear foot of the prosthetic foot and less load on the forefoot than TTA group (p < 0.05). The opposite pattern was observed in the intact foot (p < 0.05). Using heels in TTA group increased the load on the front of the intact side and the rear of the prosthetic side (p < 0.05). The balance parameters were impaired in both groups while standing barefoot in the absence of vision. However, using heel supports improved static balance in the TTA but not in the TFA group. Using heel support changed this load distribution in both groups, especially in the TTAs, and created positive changes.

Rehabilitating Amputated Hallux with Dental Implant–Supported Double Magnet in Y-Bar–Retained Prosthesis

ABSTRACT Introduction Loss of hallux leads to aesthetic deficit and functional loss, with active push-off, weight-bearing ability, and pronation all being affected. Rehabilitation can be surgical or prosthetic; however, surgical alternatives can be unpredictable in terms of aesthetics and is not cost-effective. Therefore, prosthetic rehabilitation is often favored. However, loss of all 3 phalanges makes prosthetic rehabilitation challenging due to minimal scope of retention from the residual limb. Materials and Methods This technique presents a solution to this challenge, with an implant-supported, magnet-retained silicone prosthesis, having a novel abutment design, to provide dual (magnetic and frictional) retention. Conclusions The prosthetic design improved retention, facilitated easy handling by the patient, and prevented stress concentration on implant-bone interface. Clinical Relevance The prosthetic innovation improved retention during standing and walking, and increased the patient’s confidence to perform daily activities without fear of dislodgement.

How timing and preexisting pain affect outcomes of TMR: a systematic review

Introduction: Targeted muscle reinnervation (TMR) is increasingly common in the care of major limb amputation to limit amputation-related pain. This review aims to elucidate how chronic pain states and length of delay prior to TMR affect its success and outcomes. Methods: Manuscripts were collected from three databases. Articles were first screened and excluded based on exclusion criteria. The remaining manuscripts were independently reviewed to determine inclusion. Article and patient demographics, as well as pain outcomes, were extracted. Data were analyzed based on pain condition, amputation vs. neuroma, and time from amputation/injury to surgery. Results: The literature search yielded 723 articles, with 41 meeting the inclusion criteria. Twenty-one articles included patients with residual limb pain (RLP) and phantom limb pain (PLP), including 14 on amputation and 6 on neuroma excision. Five articles included cancer-related amputation. Complex Regional Pain Syndrome (CRPS) was discussed in 3 articles, ischemia or infection in 2 articles, and neurofibromatosis 1 in 1 article. Twenty-two articles described TMR at the time of amputation. Conclusions: TMR is effective at preventing neuroma formation and limiting pain when performed at the time of amputation. Delayed patients had a greater improvement in RLP but less of an improvement in PLP, when assessed against immediate TMR patients who were compared to non-TMR standard amputees. In the presence of chronic pain states, such as CRPS, there is also improved analgesia. However, current clinical data are limited, indicating a need for further research into the use of TMR for chronic pain management.

Targeted Muscle Reinnervation Compared to Standard Peripheral Nerve Management Following Amputation: A Systematic Review and Meta-Analysis.

Chronic pain remains a significant challenge for individuals following limb amputation, with incidence of painful neuromas, phantom limb pain (PLP), and residual limb pain (RLP). Targeted muscle reinnervation (TMR) is a surgical technique designed to restore motor control information lost during amputation by redirecting residual nerves to new muscle targets. This systematic review and meta-analysis aims to compare patient-reported and functional outcomes following amputation with either TMR or standard neurological treatment (SNT). The study also includes an examination of primary versus secondary TMR and explores outcomes in highly comorbid patient populations. A search of central databases was performed, and meta-analysis was completed on extracted data where possible. Eleven studies were identified. Results indicate a significant reduction in PLP and RLP in patients undergoing TMR compared to SNT using various pain scores. TMR also demonstrates improved functional outcomes and decreased opioid use. Furthermore, results indicated patients who underwent TMR at the time of amputation (primary TMR) had improved pain scores compared with those who had TMR performed later (secondary TMR). The review emphasizes the benefits of TMR as a valuable surgical adjunct for amputee patients, while also highlighting the need for further research, especially in comorbid populations.

A clinical comparison of a digital versus conventional design methodology for transtibial prosthetic interfaces

A transtibial prosthetic interface typically comprises a compliant liner and an outer rigid socket. The preponderance of today’s conventional liners are mass produced in standard sizes, and conventional socket design is labor-intensive and artisanal, lacking clear scientific rationale. This work tests the clinical efficacy of a novel, physics-based digital design framework to create custom prosthetic liner-socket interfaces. In this investigation, we hypothesize that the novel digital approach will improve comfort outcomes compared to a conventional method of liner-socket design. The digital design framework generates custom transtibial prosthetic interfaces starting from MRI or CT image scans of the residual limb. The interface design employs FEA to simulate limb deformation under load. Interfaces are fabricated for 9 limbs from 8 amputees (1 bilateral). Testing compares novel and conventional interfaces across four assessments: 5-min walking trial, thermal imaging, 90-s standing pressure trial, and an evaluation questionnaire. Outcome measures include antalgic gait criterion, skin surface pressures, skin temperature changes, and direct questionnaire feedback. Antalgic gait is compared via a repeated measures linear mixed model while the other assessments are compared via a non-parametric Wilcoxon sign-rank test. A statistically significant (\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$P=0.032$$\\end{document}) decrease in pain is demonstrated when walking on the novel interfaces compared to the conventional. Standing pressure data show a significant decrease in pressure on novel interfaces at the anterior distal tibia (\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$P = 0.012$$\\end{document}), with no significant difference at other measured locations. Thermal results show no statistically significant difference related to skin temperature. Questionnaire feedback shows improved comfort on novel interfaces on posterior and medial sides while standing and the medial side while walking. Study results support the hypothesis that the novel digital approach improves comfort outcomes compared to the evaluated conventional method. The digital interface design methodology also has the potential to provide benefits in design time, repeatability, and cost.

CORR Insights®: What Are the Factors Associated With Revision Surgery on the Residual Limb and Functional Results in Patients With Posttraumatic Lower Limb Amputations?

CORR Insights®: What Are the Factors Associated With Revision Surgery on the Residual Limb and Functional Results in Patients With Posttraumatic Lower Limb Amputations?

Comparative study of a femoral amputated limb with and without implant

The contact pressure at the socket–residual limb interface is the most critical parameter for evaluating the comfort of a leg prosthesis. Experimental studies have analyzed this parameter for typical postures and during walking on a flat surface of an amputee; however, experimental tests require a real socket prototype equipped with transducers. To optimize socket design, this work presents a virtual approach based on a digital avatar of a patient wearing a lower limb prosthesis. Our study integrates two different types of simulations: the first concerns the femur with an implant, the second without an implant, and includes the evaluation of pressure at the socket–residual limb interface using finite element analyses (FEA). The objective of this study is to understand the distribution of loads and stresses at the interface between the residual limb and the prosthesis. The lower contact pressure is represented by CPRESS, while CSHEAR1 is the frictional shear stress component in the first local tangent direction, and CSHEAR2 is the frictional shear stress component in the second local tangent direction.

"Y appearance" infarction: caused by essential thrombocythemia.

Essential thrombocythemia (ET) is a myeloproliferative malignancy caused by the excessive proliferation of megakaryocytes in the bone marrow, resulting in the overproduction of peripheral platelets. ET can lead to thrombotic events, such as ischemic stroke (IS), though it is a rare cause of IS. Bilateral medial medullary infarction (BMMI), also known as "Y appearance" infarction due to its distinctive imaging morphology, is a rare clinical subtype of IS which typically has a poor prognosis and a high mortality rate. Herein, we report the case of a 43-year-old male with a history of ET. The patient's platelet count was poorly controlled, and he did not receive regular treatment. After developing symptoms such as dizziness, dysphagia, choking on water, slurred speech, blurred vision, and bilateral limb numbness. Head magnetic resonance imaging revealed a "Y appearance" infarction in the bilateral medial medulla. After admission, the patient was administered intravenous antiplatelet therapy with tirofiban. However, when he was switched to oral aspirin after three days, he experienced decreased muscle strength and worsening symptoms. Therefore, tirofiban was continued for 14 days. Upon discharge, the patient experienced residual limb numbness. His National Institutes of Health Stroke Scale score was 1, Modified Rankin Scale score was 0, and platelet count had decreased to the normal range. During the 9-month follow-up period after discharge, the patient still had only mild limb numbness. Our report presents a special case of "Y appearance" infarction due to ET. Owing to fluctuations in the patient's condition, he received long-term high-dose tirofiban, which ultimately led to a significant improvement in his symptoms.

Comparative biomechanical analysis of a conventional/novel hip prosthetic socket.

The aim of this study was to investigate and compare the biomechanical properties of the conventional and novel hip prosthetic socket by using the finite element and gait analysis. According to the CT scan model of the subject's residual limb, the bones, soft tissues, and the socket model were reconstructed in three dimensions by using inverse modeling. The distribution of normal and shear stresses at the residual limb-socket interface under the standing condition was investigated using the finite element method and verified by designing a pressure acquisition module system. The gait experiment compared and analyzed the conventional and novel sockets. The results show that the simulation results are consistent with the experimental data. The novel socket exhibited superior stress performance and gait outcomes compared to the conventional design. Our findings provide a research basis for evaluating the comfort of the hip prosthetic socket, optimizing and designing the structure of the socket of the hip.

Design and development of an EMG controlled transfemoral prosthesis

Electromyography (EMG) signals are biomedical signals that measure electrical currents generated by the activity of muscles when they contract. EMG is essential for optimizing the control of various prosthetic devices, particularly for transfemoral amputees, where the complexity of muscle signal integration presents significant challenges. The proposed study aims to develop a prosthetic knee that actuates in real-time using the EMG signals from the amputee’s residual limb. Pre-processing techniques are employed to obtain EMG signals from the femoris and vastus muscle targets in the transfemoral region. Moving average filters and Butterworth bandpass filters are implemented to process the raw signals. Sliding windows of various widths were applied for feature extraction. The window size of 200 ms is determined for our study based on the outcomes of the t-SNE plots and the corresponding silhouette scores. After the extraction of the pertinent features, several supervised classifier algorithms are put into practice to classify the knee flexion and extension motion. The k-nearest Neighbor (KNN) algorithm, with an accuracy rating of 80 %, proved to be suitable for motor control. Real-time control is implemented using the Raspberry Pi board to power the prosthesis allowing above-the-knee amputees to voluntarily move the leg back and forth. The EMG signals are then extracted and used to drive the DC motor. The prosthesis would therefore be able to move more precisely since the EMG readings are being gathered in real-time. Thus, this work can enhance the patient’s comfort with the ease of carrying out knee movements.

Long-term outcomes and trends in elbow arthroplasty with Coonrad-Morrey prosthesis: a retrospective study in large group of patients.

Total Elbow Arthroplasty (TEA) was first developed to treat severe rheumatoid arthritis, but its uses have grown to encompass end-stage osteoarthritis, post-traumatic arthritis, and distal humeral fractures. This study analyzes indications changes, long-term survival, complications, and post-operative functional results of the Coonrad-Morrey prostheses, enhancing the existing literature on this technique and substantial case history. We included 122 arthroplasties in 117 patients, 28 males and 89 females (mean age of 67 years) treated in our hospital between 2002 and 2016. Minimum follow-up was four years. We collect functional parameters of 48 patients (51 elbows), due to death of patients due to old age and loss at follow-up. Survival rate at five years was 90%, 85% at 10 years and 83% at 15 years. The overall medium Mayo elbow score was 79.7 ± 18.3 with the highest result in osteoarthritis patients (p < 0.005); QuickDASH score was 33.1 ± 25.5 with the worse result in rheumatoid group. Average post-operative arc of motion (ROM) was 95°±27°. There were complications in 46 out of 122 cases (37.7%) and revision surgeries were performed in 12 of them (9.8%): seven aseptic loosening, four late septic loosening, one bushing wear. In 27 instances (22.1%) was reported ulnar nerve involvement. Coonrad-Morrey prosthesis has shown satisfactory clinical results in the treatment of a wide range of pathologies. The long-term implant survivorship was satisfactory, yet the occurrence of failures and complications cannot be overlooked, above all the ulnar nerve paresthesia. There was a good recovery in quality of life, pain-free with limited residual limb disability.

Residual Deformity and Outcome in Non-Surgically Treated Tibial Shaft Fractures in Adolescents Nearing Skeletal Maturity

Background. Anatomic reduction is crucial to avoid malalignment in tibial shaft fractures in adolescents approaching physeal closure. While surgical treatment is becoming more common, casting and immobilization are still widely done for appropriately selected fractures. Local radiographic and clinical outcomes of non-surgical treatment need to be explored. Objective. The primary objective of this study was to report residual lower limb deformity of tibial shaft fractures treated non-surgically in adolescents nearing skeletal maturity. The study also identified factors or fracture characteristics that may predict these deformities and reported the clinical outcomes using the Lower Extremity Functional Scale (LEFS). Methodology. This was a cross-sectional study of 31 adolescents nearing skeletal maturity at the time of injury with acute closed tibial shaft fractures treated non-surgically at the Philippine Orthopedic Center from 2017 to 2020. Skeletal maturity and residual sagittal &amp; coronal angulation were analyzed through radiographs. Rotational alignment and leg length discrepancies were evaluated clinically. Functional outcome was measured using the LEFS. Results. Coronal plane angulation (r = -0.397; p = 0.05) and leg length discrepancy (r = -0.394; p = 0.05) were inversely correlated with LEFS scores. Coronal plane angulation was also correlated with ipsilateral fibular fractures (p = 0.007). LEFS scores were 79.39 on average (range 75 to 80). Conclusion. Among adolescents nearing skeletal maturity with isolated acute tibial shaft fractures, closed reduction and casting followed by close monitoring remains useful and effective.

Muscle recruitment during gait in individuals with unilateral transfemoral amputation due to trauma compared to able-bodied controls.

Individuals with transfemoral lower limb amputations walk with adapted gait. These kinetic and kinematic compensatory strategies will manifest as differences in muscle recruitment patterns. It is important to characterize these differences to understand the reduced endurance, reduced functionality, and progression of co-morbidities in this population. This study aims to characterize muscle recruitment during gait of highly functional individuals with traumatic transfemoral amputations donning state-of-the-art prosthetics compared to able-bodied controls. Inverse dynamic and static optimisation methods of musculoskeletal modelling were used to quantify muscle forces of the residual and intact limb over a gait cycle for 11 individuals with traumatic transfemoral amputation and for 11 able-bodied controls. Estimates of peak muscle activation and impulse were calculated to assess contraction intensity and energy expenditure. The generalized estimation equation method was used to compare the maximum values of force, peak activation, and impulse of the major muscles. The force exhibited by the residual limb's iliacus, psoas major, adductor longus, tensor fasciae latae and pectineus is significantly higher than the forces in these muscles of the intact contralateral limb group and the able-bodied control group (p < 0.001). These muscles appear to be recruited for their flexor moment arm, indicative of the increased demand due to the loss of the plantar flexors. The major hip extensors are recruited to a lesser degree in the residual limb group compared to the intact limb group (p < 0.001). The plantar flexors of the intact limb appear to compensate for the amputated limb with significantly higher forces compared to the able-bodied controls (p = 0.01). Significant differences found in impulse and peak activation consisted of higher values for the limbs (residual and/or intact) of individuals with transfemoral lower limb amputations compared to the able-bodied controls, demonstrating an elevated cost of gait. This study highlights asymmetry in hip muscle recruitment between the residual and the intact limb of individuals with transfemoral lower limb amputations. Overall elevated impulse and peak activation in the limbs of individuals with transfemoral amputation, compared to able-bodied controls, may manifest in the reduced walking endurance of this population. This demand should be minimised in rehabilitation protocols.

What Are the Factors Associated With Revision Surgery on the Residual Limb and Functional Results in Patients With Posttraumatic Lower Limb Amputations?

Lower limb amputations performed after trauma are associated with a high risk of revision surgery. While the factors influencing revision surgery in the upper limbs have been studied, no studies have analyzed these factors in the lower limbs. Existing explanations for these revision surgeries are unclear, often leaving patients uninformed. Surgeons also lack the tools to explain the factors that influence repeat operations to patients. Therefore, the aim of this study was to provide surgeons with some answers so they can inform their patients undergoing posttraumatic lower limb amputation, whether military or civilian. (1) What was the survivorship of the initial amputation free from any revision surgery? (2) What patient- and injury-related factors were associated with revision amputation? (3) Do these factors influence functional outcomes in these patients? A single-center, retrospective study was conducted between January 2010 and February 2020 on patients who had undergone traumatic lower limb amputation. Between January 2010 and February 2020, 322 patients underwent amputation or were followed up at Percy Military University Hospital. Thirty-one patients had undergone amputation at another center, 178 had undergone amputation for nontraumatic reasons, and 27 patients had only upper limb amputations. Of those remaining, 1 died before 6 months, and 6% (5 of 86) were not fitted with a prosthesis, leaving 99% (85 of 86) for survivorship free from revision analysis and 93% (80 of 86) for functional endpoints analysis in this retrospective study at a median of 6.5 years (IQR 5 to 9) following the index amputation. The median age at the time of amputation was 31 years (IQR 26 to 52), 85% (72 of 85) of patients were men, and 31% (26 of 85) were military personnel. Revision surgery was defined as surgery performed at or after 6 months to ensure that the residual limb was healed and fitted with a prosthesis. Revision procedures performed before 6 months (median 2 [IQR 0 to 7]) were considered as part of the initial residual limb formation surgery. We performed Kaplan-Meier survivorship analysis for the time free from revision amputation from 6 months after amputation. We considered the competitive risk of death using a Fine-Gray model by an ascending stepwise procedure. To answer our third research question, we performed a chart review and assessed patients' use of prostheses and assistive devices and the percentage of patients who returned to work. An ordinal logistic regression was used to analyze the factors influencing functional outcome using an ascending stepwise procedure. A total of 85 patients (94 limbs) were included, of whom 25 (27 limbs) underwent a revision surgery on the residual limb > 6 months after amputation. Kaplan-Meier survival estimates indicated that 5 years after the initial amputation 64% (95% confidence interval 53% to 77%) of the patients remained free from revision surgery on their residual limb. Factors associated with increased odds of revision amputation were smoking (subdistribution HR 2.6 [95% CI 1.2 to 5.8]; p = 0.02) and an age of > 50 years (subdistribution HR 0.3 [95% CI 0.1 to 0.8]; p = 0.01). Ninety-four percent (80 of 85) of patients were fitted with prostheses, and 40% (32 of 80) of patients used material or human assistance for simple activities of daily living. Seventy-one percent of patients (57 of 80) had returned to work. Ordinal logistic regression revealed an association between preinjury sports activity and the absence of need for assistance in daily activities (OR 9 [95% CI 2.9 to 31.8]; p < 0.001). Smoking appeared to be an associated risk factor for residual limb revision surgery in posttraumatic lower limb amputations and is potentially modifiable. Being at least 50 years of age seemed to be associated with a lower incidence of revision surgery, which is probably linked to lower functional demands made on limbs beyond this age. Our study showed a remarkable rate of fitting with a prosthetic device, with an improved functional result if the patient was athletic before the trauma. These results provide more precise information on the care pathway to be considered for each patient. A study with a much larger sample would make it possible to assess the risk factors for the occurrence of each complication involving revision surgery. Level III, therapeutic study.

Neuroma morphology: A macroscopic classification system.

Neuromas come in different shapes and sizes; yet the correlation between neuroma morphology and symptomatology is unknown. Therefore, we aim to investigate macroscopic traits of excised human neuromas and assess the validity of a morphological classification system and its potential clinical implications. End-neuroma specimens were collected from prospectively enrolled patients undergoing symptomatic neuroma surgery. Protocolized images of the specimens were obtained intraoperatively. Pain data (Numeric rating scale, 0-10) were prospectively collected during preoperative interview, patient demographic and comorbidity factors were collected from chart review. A morphological classification is proposed, and the inter-rater reliability (IRR) was assessed. Distribution of neuroma morphology with patient factors, was described. Forty-five terminal neuroma specimens from 27 patients were included. Residual limb patients comprised 93% of the population, of which 2 were upper (8.0%) and 23 (92.0%) were lower extremity residual limb patients. The proposed morphological classification, consisting of three groups (bulbous, fusiform, atypical), demonstrated a strong IRR (Cohen's kappa = 0.8). Atypical neuromas demonstrated higher preoperative pain, compared with bulbous and fusiform. Atypical morphology was more prevalent in patients with diabetes and peripheral vascular disease. A validated morphological classification of neuroma is introduced. These findings may assist surgeons and researchers with better understanding of symptomatic neuroma development and their clinical implications. The potential relationship of neuroma morphology with the vascular and metabolic microenvironment requires further investigation.

Evaluation of MRI features of neuromas in oncological amputees, and the relation to pain.

The impact of time on neuroma growth and morphology on pain intensity is unknown. This study aims to assess magnetic resonance imaging (MRI) differences between symptomatic and non-symptomatic neuromas in oncological amputees, and whether time influences MRI-detected neuroma dimensions and their association with pain. Oncological patients who underwent traditional extremity amputation were included. Post-amputation MRIs were assessed before decision for neuroma surgery. Chart review was performed for residual limb pain (numeric rating scale, 0-10) and the presence of neuropathic symptoms. Neuromas were classified as symptomatic or non-symptomatic, with neuroma size expressed as radiological neuroma-to-nerve-ratio (NNR). Among 78 neuromas in 60 patients, the median NNR was 2.0, and 56 neuromas (71.8%) were symptomatic with a median pain score of 3.5. NNR showed no association with symptomatology or pain intensity but correlated with a longer time-to-neuroma-excision interval and a smaller nerve caliber. Symptomatic neuromas were associated with lower extremity amputation, T2 heterogeneity, and the presence of heterotopic ossification. Lower extremity amputation, T2 heterogeneity, perineural edema, and presence of heterotopic ossification were associated with more painful neuromas. MRI features associated with symptomatic neuromas and pain intensity were identified. Awareness of the potential clinical significance of these imaging features may help in the interpretation of MRI exams and may aid clinicians in patient selection for neuroma surgery in oncological amputees.

Restoration of grasping in an upper limb amputee using the myokinetic prosthesis with implanted magnets.

The loss of a hand disrupts the sophisticated neural pathways between the brain and the hand, severely affecting the level of independence of the patient and the ability to carry out daily work and social activities. Recent years have witnessed a rapid evolution of surgical techniques and technologies aimed at restoring dexterous motor functions akin to those of the human hand through bionic solutions, mainly relying on probing of electrical signals from the residual nerves and muscles. Here, we report the clinical implementation of an interface aimed at achieving this goal by exploiting muscle deformation, sensed through passive magnetic implants: the myokinetic interface. One participant with a transradial amputation received an implantation of six permanent magnets in three muscles of the residual limb. A truly self-contained myokinetic prosthetic arm embedding all hardware components and the battery within the prosthetic socket was developed. By retrieving muscle deformation caused by voluntary contraction through magnet localization, we were able to control in real time a dexterous robotic hand following both a direct control strategy and a pattern recognition approach. In just 6 weeks, the participant successfully completed a series of functional tests, achieving scores similar to those achieved when using myoelectric controllers, a standard-of-care solution, with comparable physical and mental workloads. This experience raised conceptual and technical limits of the interface, which nevertheless pave the way for further investigations in a partially unexplored field. This study also demonstrates a viable possibility for intuitively interfacing humans with robotic technologies.

Functional Disability at 3 Months in Patients with Residual Limb Swelling after Snakebite Envenoming.

Limited data indicate that snakebite survivors have persistent musculoskeletal disability. We assessed the pain and functional disability at hospital discharge and after 3 months in 47 patients treated for snakebite envenoming and with at least a specified amount of local swelling at the time of hospital discharge, using the numerical pain rating scale and the Patient-Specific Functional Scale (PSFS). Russell's viper was the most common biting snake species identified. At hospital discharge, the median pain score was 2 (0-3); 9 (19%) patients reported mild persisting pain at 3 months. The median PSFS score at hospital discharge was 3.7 (3.3-4.0), which improved to 8.3 (6.3-9.0) on follow-up (P <0.001); 32 (68%) patients had a PSFS score of 8.9 or below on follow-up. We conclude that snakebite envenoming could be associated with persisting functional disability at 3 months even in the absence of local complications such as skin necrosis and compartment syndrome.