Although a number of above-knee amputees have expressed a desire to participate in recreational activities involving running, no currently available lower limb prosthesis has proven adequate in allowing amputees to achieve a natural, efficient, one-to-one running gait. Until recently, amputee runners such as Terry Fox and Steve Fonyo have adopted a variety of asymmetrical gaits, although the Terry Fox Jogging Prosthesis has allowed some amputees to achieve an inefficient one-to-one running pattern. The objective is to design a conservative running prosthesis which will functionally imitate the intact limb during running activities. The prosthesis performance criteria were established for both stance and swing, based on an examination of non-amputee running biomechanics. The prosthesis incorporates a shank unit assembly which linearly compresses upon heel-strike, absorbing the impact energies in a helical coil compression spring, and then uses a ratchet device to store these impact energies throughout the stance phase. In late stance, the natural dorsi flexion of the prosthetic foot initiates the release of the stored energies, propelling the amputee upward and forward into the swing phase. It is recommended that a comprehensive biomechanical gait analysis be performed on the prosthesis' operation to allow for optimization of its configuration and performance. In conclusion, the features of this prosthesis will allow above-knee amputees to achieve a more natural, one-to-one running gait and participate more actively in activities involving running. / Thesis / Master of Engineering (ME)

No description available.

The aim of this research was to examine tactile sensitivity in the skin of the leg and foot sole of healthy control subjects and below knee amputees and to examine its association with balance. For control subjects, the glabrous skin of the foot had higher sensitivity compared to the hairy skin of the leg, similar to previous literature in the upper limb. For all diabetic amputees examined, tactile sensitivity acuity in the lower limb was considerably lower than age matched controls in both the amputated and intact limbs, due to peripheral neuropathy. The traumatic amputee examined showed elevated sensitivity compared to controls for vibration perception at 40Hz and 250Hz in both the intact and amputated limbs. This may be due to cortical reorganisation of the primary somatosensory cortex which is known to occur following amputation. Further investigation of the tactile sensitivity of lower limb amputees is recommended. / re-submission of previously rejected thesis. / NSERC Discovery Grant

Lower-extremity amputees face numerous challenges when returning to daily activities. Amongst these challenges is the ability to safely and dynamically transition from one locomotor state to another. Switching between level-ground, ramp, and stair locomotion poses an increased risk as lower-extremity functionality is compromised. Powered prosthetics have been proposed as a solution to this problem. Hypothetically, powered prosthetics would be able to return full functional to the amputated limb. The most common and successful source of information used in algorithms for lower-extremity prosthetics has been electromyography. However, in practice, amputees remain unable to easily actuate the mechanized joints of powered prostheses. Therefore, the current project aimed to identify myoelectric activation differences in lower-extremity musculature during the gait cycles preceding locomotor transition in able-bodied, trans-tibial, and trans-femoral subjects to assist efforts in developing robust classification algorithms for locomotor transitions. Analysis of electromyography was completed to determine if there were periods of activation where classification algorithms could utilize differences in myoelectric activation to appropriately control joint actuation in a subset of eight transitions that included level-ground locomotion and switching to either ramp or stair locomotion and vice versa. Ramp transitions were fundamentally similar to level-ground locomotion and elicited no differences in myoelectric activation. Stair transitions were found to alter muscle activation patterns in able-body and trans-tibial subjects. Trans-femoral subjects differentiated from able-bodied and trans-tibial subjects due to increased recruitment pattern variability. These patterns are distinct and may suggest individual learning patterns within the trans-femoral amputee population. Further investigation of these patterns may be warranted. Findings within able-bodied and trans-tibial subjects suggest common transition based differences within each respective population. Trans-tibial classification algorithms may be developed to utilize this information, using schemes that are focused on important areas during the gait cycle.

Indiana University-Purdue University Indianapolis (IUPUI) / The primary objectives of this thesis are (1) to discuss the current understanding of phenomena associated with, proposed mechanisms of, and suggested treatments for amputation related pain, (2) to describe the software developed for analyzing results of a clinical study for the treatment of phantom limb pain (PLP), (3) to discuss the methods for a multi-center trial by the EPIONE consortium along with presenting preliminary results, and (4) to discuss the methods and results of a case study involving a new therapy modality for alleviating PLP. Each objective has been expanded into a chapter as described below. Chapter 1 serves as a literature review introducing the topic of amputation, associ- ated phenomena, and proposed mechanisms. The chapter also discusses the currently available treatments and the instruments used to measure PLP. Key topics include the definition of PLP, the prevalence of PLP, current treatment options for PLP, and experimental measurement of PLP. The final objective of this chapter is to introduce topics related to the investigation paradigm utilized for the studies following in Chapter 4 and Chapter 5. Therefore, a minor emphasis has been put on surface electrical stimulation (SES) and operant conditioning. As with any multi-center clinical study, coordination is key. Chapter 2 introduces the common clinical protocol (CCP) and methods of analysis for the clinical trials conducted by the EPIONE consortium. In order to analyze results in an automated fashion, a software tool was developed. This tool, the EPIONE Extraction Program (EEP) along with its extension the Group Analysis Module (GAM), is the focus of Chapter 3. A high-level overview of the requirements, process flow, and software testing are described. This chapter also discusses the methods of analysis for several self-report instruments used to determine effect size in Chapter 4 and Chapter 5. The outputs of the software tools make up the results presented and described in these chapters. In addition to the details included in Chapter 3, supplemental information is available in Appendix A and Appendix B, which are the detailed User Guides for the EEP and GAM. Chapter 4 reviews the pilot study data conducted by the EPIONE consortium. The primary and two secondary instruments used for analysis are discussed. This chapter provides a brief overview of results from the group. Each clinical site used slightly different variations of a common clinical protocol to better understand what effectively drives alleviation of PLP and to allow comparison of results. The work done at Indiana University - Purdue University Indianapolis (IUPUI) represents a small part of several other universities involved in the EPIONE consortium. Chapter 5 focuses on a case study at IUPUI with a more in-depth review of data collected throughout the study period. Using SES, we seek to reverse cortical reorganization by giving meaningful stimuli through existing circuitry. In this chapter the present work is discussed by introducing a case study in detail with an analysis of psychophysical data.

With the popularity of outdoor activities like hiking, the demands of certain types of employment, or being a student, an individual’s ability to carry a load is an important mobility consideration. By understanding the changes to an individual’s gait when supporting a backpack load, an individual’s ability to carry heavy loads for prolonged periods could be improved. Most biomechanical studies have examined the changes in able-bodied gait when carrying a load. However, research is lacking on the effect of backpack loads on amputee gait patterns. This project examined the effects of a backpack load on the gait patterns of unilateral transtibial amputees. Ten participants performed walking trials on four surfaces (level ground, uneven ground, walking up an incline, and walking down an incline), without a pack and with a pack. A total of 40 trials were collected per subject, with 10 trials collected on each surface. Three-dimensional motion data were collected with an eight-camera Vicon Motion Analysis system to describe limb motion as well as compare kinematic outcomes between tasks and conditions. Force platform data were collected during the level ground trials and used to calculate kinetic measures for both limbs. With the addition of the pack changes were seen on each surface, with different changes occurring to each limb. The ramp up surface created the most changes when comparing the two conditions. The only change seen across all four surfaces was a decrease in ankle dorsiflexion before push-off on the prosthetic limb. The two next most common changes were increases in knee and hip flexion during weight-acceptance.

With the popularity of outdoor activities like hiking, the demands of certain types of employment, or being a student, an individual’s ability to carry a load is an important mobility consideration. By understanding the changes to an individual’s gait when supporting a backpack load, an individual’s ability to carry heavy loads for prolonged periods could be improved. Most biomechanical studies have examined the changes in able-bodied gait when carrying a load. However, research is lacking on the effect of backpack loads on amputee gait patterns. This project examined the effects of a backpack load on the gait patterns of unilateral transtibial amputees. Ten participants performed walking trials on four surfaces (level ground, uneven ground, walking up an incline, and walking down an incline), without a pack and with a pack. A total of 40 trials were collected per subject, with 10 trials collected on each surface. Three-dimensional motion data were collected with an eight-camera Vicon Motion Analysis system to describe limb motion as well as compare kinematic outcomes between tasks and conditions. Force platform data were collected during the level ground trials and used to calculate kinetic measures for both limbs. With the addition of the pack changes were seen on each surface, with different changes occurring to each limb. The ramp up surface created the most changes when comparing the two conditions. The only change seen across all four surfaces was a decrease in ankle dorsiflexion before push-off on the prosthetic limb. The two next most common changes were increases in knee and hip flexion during weight-acceptance.

No description available.

Above-elbow myoprostheses aim to restore the functionality of amputated limbs and improve the quality of life of amputees. By using electromyography electrodes attached to the surface of the skin, amputees are able to control motors in myoprostheses by voluntarily contracting the muscles of their residual limb. An advance in myoelectric control called targeted muscle reinnervation (TMR) reinnervates severed nerves into healthy muscle tissue and increases the number of muscle sites available for use in control purposes. In order to improve rehabilitation after TMR surgery, an inexpensive myoelectric training tool has been developed in collaboration with the Glenrose Rehabilitation Hospital that can be used by TMR patients for biofeedback applications. The training tool consists of a robotic arm, signal acquisition hardware, controller software, and a graphical user interface. This dissertation describes the design and evaluation of the training tool and its use as a research platform for testing novel controllers.

With the popularity of outdoor activities like hiking, the demands of certain types of employment, or being a student, an individual’s ability to carry a load is an important mobility consideration. By understanding the changes to an individual’s gait when supporting a backpack load, an individual’s ability to carry heavy loads for prolonged periods could be improved. Most biomechanical studies have examined the changes in able-bodied gait when carrying a load. However, research is lacking on the effect of backpack loads on amputee gait patterns. This project examined the effects of a backpack load on the gait patterns of unilateral transtibial amputees. Ten participants performed walking trials on four surfaces (level ground, uneven ground, walking up an incline, and walking down an incline), without a pack and with a pack. A total of 40 trials were collected per subject, with 10 trials collected on each surface. Three-dimensional motion data were collected with an eight-camera Vicon Motion Analysis system to describe limb motion as well as compare kinematic outcomes between tasks and conditions. Force platform data were collected during the level ground trials and used to calculate kinetic measures for both limbs. With the addition of the pack changes were seen on each surface, with different changes occurring to each limb. The ramp up surface created the most changes when comparing the two conditions. The only change seen across all four surfaces was a decrease in ankle dorsiflexion before push-off on the prosthetic limb. The two next most common changes were increases in knee and hip flexion during weight-acceptance.