Limb prosthesis

OBJECTIVE: To formulate a prognostication model in the early post-operation phase of lower limb amputation to predict patient's ability to ambulate with a prosthesis post rehabilitation. DESIGN: Retrospective cohort study, using data collected from electronic medical records. Predictive factors and prosthetic ambulation outcomes post rehabilitation were used to develop prognostic models via machine learning techniques. SETTING: Regional hospital's ambulatory rehabilitation clinic...

Existing controllers for robotic powered prostheses regulate the prosthesis speed, timing, and energy generation using predefined position or torque trajectories. This approach enables climbing stairs step-over-step. However, it does not provide amputees with direct volitional control of the robotic prosthesis, a functionality necessary to restore full mobility to the user. Here we show that proportional electromyographic (EMG) control of the prosthesis knee torque enables volitional control of a powered knee prosthesis during stair climbing...

OBJECTIVES: Adaptation of upper-limb impedance (stiffness, damping, inertia) is crucial for humans to physically interact with the external environment during grasping and manipulation tasks. Here, we present a novel framework for Adaptive Impedance Control of Upper-limb Prosthesis (AIC-UP) based on surface electromyography (sEMG) signals. METHODS: AIC-UP uses muscle-tendon models driven by sEMG signals from agonist-antagonist muscle groups to estimate the human motor intent as joint kinematics, stiffness and damping...

Powered lower-limb prostheses have the potential to improve amputee mobility by closely imitating the biomechanical function of the missing biological leg. To accomplish this goal, powered prostheses need controllers that can seamlessly adapt to the ambulation activity intended by the user. Most powered prosthesis control architectures address this issue by switching between specific controllers for each activity. This approach requires online classification of the intended ambulation activity. Unfortunately, any misclassification can cause the prosthesis to perform a different movement than the user expects, increasing the likelihood of falls and injuries...

OBJECTIVE: This study aims to biomimetic design a new 3D-printed lattice hemipelvis prosthesis and evaluate its clinical efficiency for pelvic reconstruction following tumor resection, focusing on feasibility, osseointegration, and patient outcomes. METHODS: From May 2020 to October 2021, twelve patients with pelvic tumors underwent tumor resection and subsequently received 3D-printed lattice hemipelvis prostheses for pelvic reconstruction. The prosthesis was strategically incorporated with lattice structures and solid to optimize mechanical performance and osseointegration...

OBJECTIVE: To determine if lower limb prosthesis (LLP) sophistication is associated with patient-reported mobility and/or mobility satisfaction, and if these associations differ by amputation level. DESIGN: Cohort study that identified participants through a large national database and prospectively collected self-reported patient outcomes. SETTING: The Veterans Administration (VA) Corporate Data Warehouse, the National Prosthetics Patient Database, participant mailings and phone calls...

INTRODUCTION: For individuals with limb loss, bone-anchored implants create a direct structural and functional connection to a terminal prosthesis. Here, we characterized the mechanical loads distal to the abutment during several functional performance tests in Service members with transfemoral (TF) limb loss, to expand on prior work evaluating more steady-state ambulation on level ground or slopes/stairs. METHODS: Two males with unilateral TF limb loss and two males with bilateral TF limb loss participated after two-stage osseointegration (24 and 12 months, respectively)...

PURPOSE: Osseointegration (OI) is a novel alternative to traditional socket-suspended prostheses for lower-limb amputees, eliminating the socket-skin interface and allowing for weight bearing directly on the skeletal system. However, the stoma through which the implant attaches to the external prosthesis creates an ingress route for bacteria, and infection rates as high as 66% have been reported. The aims of this study are to classify infection management and long-term outcomes in this patient population to maximize implant salvage...

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OBJECTIVE: We analyse and interpret arm and forearm muscle activity in relation with the kinematics of hand pre-shaping during reaching and grasping from the perspective of human synergistic motor control. APPROACH: Ten subjects performed 6 tasks involving reaching, grasping and object manipulation. We recorded electromyographic (EMG) signals from arm and forearm muscles with a mix of bipolar electrodes and high-density (HD) grids of electrodes. Motion capture was concurrently recorded to estimate hand kinematics...

This study aimed to compare the ground reaction forces (GRFs) and spatio-temporal parameters as well as their asymmetry ratios in gait between individuals wearing a transfemoral prosthetic simulator (TFSim) and individuals with unilateral transfemoral amputation (TFAmp) across a range of walking speeds (2.0-5.5 km h-1 ). The study recruited 10 non-disabled individuals using TFSim and 10 individuals with unilateral TFAmp using a transfemoral prosthesis. Data were collected using an instrumented treadmill with built-in force plates, and subsequently, the GRFs and spatio-temporal parameters, as well as their asymmetry ratios, were analysed...

Primary bone sarcomas are rare tumours, comprising approximately 1-2% of adult and around 13-15% of all paediatric cancers. Limb salvage surgery is a challenge in complex musculoskeletal tumours. Young age adds to its complexity, since the growth potential of the reconstruct has to be considered to have optimal function of the salvaged limb. An observational retrospective study performed on 52 paediatric patients between Jan 2011 and Dec 2018 with malignant bone tumour of lower limbs had been assessed for postoperative functional outcomes with questionnaires and clinico-radiological examination for functional and oncological outcome...

The aim of this study is to evaluate the level of accuracy and precision of bone scan (BS), MRI, and digital radiography (DR) to measure long bone tumors to design custom-made prosthesis (CMP)/modular prosthesis (MP) in limb salvage surgery (LSS) with the help of phantom and patient's study. There are two separate groups: one is the phantom study and another one is the patient's study. The phantom study is done with the Jaszack Phantom for the Gamma camera and the indigenous phantom for the MRI and DR. Three independent imaging professionals (nuclear medicine physicians and radiologists) measured the distance between standardized, preselected points on the Jaszack phantom in the Gamma Camera (GC) and indigenous phantom on the coronal and sagittal view of the MRI scan and in digital radiography...

Intraluminal thrombus formation (ILT) is a recently discovered and highly clinically relevant complication after frozen elephant trunk implantation in cardiovascular surgery. In this phenomenon, a thrombus forms within the lumen of the stent graft component of the frozen elephant trunk prosthesis and puts the patient at risk for downstream embolization with visceral or lower limb ischemia. Incidence of ILT reported in the currently available studies ranges from 6% to 17% of patients after frozen elephant trunk implantation...

Megaprostheses are well-known, reliable, and effective reconstruction prostheses used in oncologic surgery for limb salvage in patients affected by primary or metastatic bone tumors. Rehabilitation plays a major role after MUTARS replacement, with the aim of improving function after surgery and maintaining the highest possible quality of life. Only a few studies have been published about the use of megaprostheses for the upper limb. The aim of this narrative review is to describe the results of functional and rehabilitative outcomes of patients affected by bone primary or metastatic bone cancer of the upper limb and surgically treated with MUTARS prostheses...

BACKGROUND: Mobility is a major goal of prosthetic and orthotic rehabilitation, and use of outcome measures to evaluate mobility is necessary for good clinical practice. To support the use of outcome measures worldwide, work is needed to translate relevant instruments and adapt them for use in multiple cultures. OBJECTIVES: The objective of this research was to use a standardized method to translate the Locomotor Capabilities Index-5 (LCI-5) into Khmer, the national language in Cambodia, and to evaluate its cultural integrity by assessing it with a group of prosthesis and orthosis users...

PURPOSE: Intra-articular distal femur fractures in patients with a lower extremity amputation can present a technical challenge for the treating surgeon in what may be otherwise considered a routine procedure in non-amputees. Difficulties with positioning, fracture reduction, limb contractures, and stump osteoporosis can present challenges with treatment. Here, we describe the surgical technique and outcome of a case series of amputee patients with AO/OTA 33C femur fractures. METHODS: Retrospective case series of five patients with a comminuted supracondylar distal femur fracture with intercondylar extension proximal to a below-knee amputation treated with retrograde intramedullary nail at a single Level 1 trauma center from January 1, 2021, to January 1, 2023...

Objective : To compare the function and muscle strength of the limb between patients undergoing knee arthroplasties using primary implants with posterior stabilization (control group) and patients with rotating hinge implants (Hinge group). Methods : Function assessment was performed using the Knee Society Score (KSS) and muscle strength using an isokinetic dynamometer using a speed of 60°/s. Results : 43 patients were analyzed, who underwent 51 surgeries, with the Hinge group comprising 25 surgeries and the control group comprising 26 primary surgeries...

Eliminating necrotic and infected tissues is crucial for limb salvage in patients with chronic limb-threatening ischemia (CLTI). However, extensive lesions that involve the midfoot frequently result in transtibial amputation, restricting ambulation and independent life. The Modified Pirogoff amputation, which includes a 90° rotation of the calcaneus and fixation with the tibia, has good functional outcomes in trauma cases. Here, we report two patients with CLTI successfully managed by a combination of revascularization and modified Pirogoff amputation, resulting in preserved ambulation without a prosthesis...

BACKGROUND: A prosthetic device is designed based on the quantitative analysis of muscle MRI which will improve the muscle control achieved with functional electrical stimulation/ guided robotic exoskeletons. Electromyography (EMG) provides muscle functionality information while MRI provides the physiological and functionality of muscles. The sensor feedbacks were used for the bionic prosthesis, but the length of muscle using image processing was not correlated. OBJECTIVE: To investigate and perform qualitative and quantitative assessment of thigh muscle using MRI...