Temporal and spatial gait characteristics of transfemoral amputees fitted with osseointegrated fixation: preliminary data

Background \ud The conventional method of attachment of prosthesis involves on a socket. A new method relying on osseointegrated fixation is emerging. It has significant prosthetic benefits. Only a few studies demonstrated the biomechanical benefits.\ud Purpose\ud The ultimate aim of this study was to characterise the functional outcome of transfemoral amputees fitted with osseointegrated fixation, which can be assess through temporal and spatial gait characteristics. The specific objective of this preliminary study was to present the key temporal and spatial gait characteristics. \ud Methods\ud Four male transfemoral amputees fitted with a fixation were asked to performe 3 trials of straight level walking. The speed of walking, cadence, duration of gait cycle, support and swing phases, length of stride and step, and walking base were extracted from displacements of foot markers using a 3D motion analysis system recording at 200 Hz. \ud Results\ud The speed of walking and the cadence were 0.81±0.16 m/s and 46.03±4.70 steps/min, respectively. The duration of the gait cycles, support and swing phases were 1.31±0.13 s, 0.76±0.07 s and 0.55±0.07 s, respectively. The stride and step length, and walking base were 1.29±0.09 m, 0.10 ± 0.65 m and -0.09 ± 0.138 m for the prosthetic leg, and 1.31±0.07 m, 1.00±0.64 m and 0.11 ± 0.12 m for the sound leg, respectively. \ud Conclusion\ud The results demonstrate that the amputees fitted with an osseointegrated fixation showed a highly functional walk compared to normative data presented in previous studies focusing on amputees fitted with a socket and able-bodied

Loads at the implant-prosthesis interface during free and aided ambulation in osseointegrated transfemoral prostheses

Bone-anchored attachment of amputation limb prostheses is increasingly becoming a clinically accepted alternative to conventional socket suspension. The direct transfer of loads demands that the percutaneous implant system and the residual bone withstand all forces and moments transferred from the prosthesis. This study presents load measurements recorded at the bone-anchored attachment in 20 individuals with unilateral transfemoral amputation performing the everyday ambulatory activities: level ground walking, stairs ascent/descent and slope ascent/descent. Mean peak values for the sample populations across activities ranged from 498–684 N for the resultant force, 26.5–39.8 Nm for the bending moment, and 3.1–5.5 Nm for the longitudinal moment. Significant differences with respect to level walking were found for the resultant force during stairs ascent, (higher, p = 0.002), and stairs descent, (lower, p = 0.005). Using a crutch reduced the peak resultant forces and the peak bending moments with averages ranging from 5.5–12.6 % and 13.2–15.6 %, respectively. Large inter-participant variations were observed and no single activity resulted in consistently higher loading of the bone-anchored attachment across the participants. Results from this study can guide future development of percutaneous osseointegrated implant systems for limb prostheses and their rehabilitation protocols

Validation of inertial measurement units with optical tracking system in patients operated with Total hip arthroplasty

Patient reported outcome measurement (PROMs) will not capture in detail the functional joint motion before and after total hip arthroplasty (THA). Therefore, methods more specifically aimed to analyse joint movements may be of interest. An analysis method that addresses these issues should be readily accessible and easy to use especially if applied to large groups of patients, who you want to study both before and after a surgical intervention such as THA. Our aim was to evaluate the accuracy of inertial measurement units (IMU) by comparison with an optical tracking system (OTS) to record pelvic tilt, hip and knee flexion in patients who had undergone THA.This article is freely available via Open Access. Click on the Publisher's URL to access the full-text

The Rise and Fall of Cheap Chinese Goods in Ecuadorian Popular Markets: The Limits of Post-Neoliberal Development in Correa's Ecuador

In contrast to its neighbors Colombia and Peru, Ecuador has used tariffs to regulate the supply of imported Chinese-made goods. This article reports on research carried out in 2015 in relation to traders and manufacturers in four cities in the northern Ecuadorian Andes: Otavalo, Atuntaqui, Ibarra, and Tulcan. It focuses on Chinese-made apparel and describes the business practices and economic aspirations of the parallel trading diasporas—one Quichua, the other Chinese—that embraced these textiles. Some domestic manufacturing has benefited from tariffs and a newly active state. However, since Ecuador's fiscal “dollarization” crisis of the early 2000s, many indigenous traders have shifted to marketing Asian and especially Chinese-made goods as a way of preserving livelihoods and commercial diasporic communities. With profits pushed to near zero, informal, culturally encoded habits of credit and professional courtesy have taken on an outsize role in the survival of not just individual enterprise but entire trading communities

Analysis of body motions based on optical markers. Accuracy, error analysis and clinical applications.

This thesis aims to evaluate the influence of soft-tissue artefacts on analyses of body motions based on optical markers. A second aim is to apply instrumented gait analysis in clinical situations. Introduction: Instrumented gait analysis has been used since 1960 as a clinical evaluation/investigative tool at orthopaedic clinics. The technique is based on a number of reflective spherical markers attached to the skin. The position of the skin markers is recorded as the subject walks through the measurement volume. Recorded data form the basis when monitoring movements of body segments. The crucial and still not completely explored issue is to what extent these systems are able to reproduce the movement of the body segment that is being studied. Material and methods: In Study I, the skin movement at the foot was studied using skin markers and radiographs. The subjects stood on one foot in three positions, 20° dorsal flexion, a neutral position and 30° plantar flexion, while radiographs were exposed. In Study II, the aim was to study problems with soft-tissue movement along the lower extremity. Skin and underlying structures were provoked partly by anterior-posterior and longitudinal strain and partly by being put into vibration to investigate their stiffness and damping characteristics. The aim of Study III was to examine the accuracy of the optical tracking system used throughout Studies IV-V by simultaneous recording using skeletal markers and radiostereometry (RSA). Nine patients with a total knee arthroplasty (2 males/7 females, median age: 63.1 years; range 59-72) were included in Study III. In Study IV, 20 patients with bilateral spastic cerebral palsy (15 males/5 females median age: 12.9 years, range 9.4-15.3) and 20 controls (13 males/7 females, median age: 13.0 years; range 10.2-15.7) were included. For Study V, nineteen unilateral transfemoral amputee patients (9 males/10 females, median age: 46.5 years; range 19.9-62.3) and fifty-seven matched controls were included. Results: Studies of soft tissue motions on the foot revealed marker movement in relation to the bone up to 4.3 mm at the ankle, which decreased gradually to 1.8 mm at the first inter-phalangeal joint. Soft-tissue movements mainly occurred in the anterior-posterior direction of the leg and pronounced self-oscillations were recorded when markers were placed on wands. The results from comparisons between RSA and OTS showed good agreement regarding extension/flexion motions. For abduction/adduction and in-/external rotation, significant differences between the two systems were observed. The group with cerebral palsy was weaker in all muscle groups in the lower limbs and they walked at a slower speed. A significant relationship between plantar flexing torque and the strength of six of the eight investigated muscle groups could be detected in patients with cerebral palsy. An even stronger relationship (rho=0.58-0.76) was found between generating power and muscle strength in all eight muscle groups. Two years after conversion from a conventional to bony anchored leg prosthesis, femoral amputees improved their hip extension and reduced their anterior pelvic tilt. Conclusion: Instrumented gait analysis is a non-invasive and valuable tool to study body motions. Knee motions in the sagittal plane (flexion/extension) are close to data obtained from RSA based on skeletal markers, whereas the resolution of rotations in the two other planes is poorer, probably due to soft tissue motions and geometrical reasons. Further comparative studies with simultaneous use of skeletal and superficial skin markers are needed to explore this issue further; not least concerning the hip and ankle joint

An innovative sealed shoe to off-load and heal diabetic forefoot ulcers – a feasibility study

Background: Non-removable knee-high devices are the gold standard to treat diabetic foot ulcers located on the plantar forefoot, but they immobilize the ankle, which restricts daily life activities and has negative effects on joint functioning. Objective: To investigate the feasibility of sealing a therapeutic shoe to off-load and heal diabetic forefoot ulcers. Design: A case series of seven men with type 2 diabetes and a metatarsal head ulcer were prescribed therapeutic shoes and custom-made insoles. The shoe was sealed with a plastic band. Off-loading was assessed with the F-scan pressure measurement system. Adherence to wearing the shoe was assessed with a temperature sensor and by documenting the status of the seal. Results: The off-loading was effective and all ulcers healed. Median time to healing was 56 days (range 8–160). Complications were secondary ulcer (n = 1) and plantar hematoma (n = 1). Five of seven participants did not disturb the seal. Conclusions: Sealing a therapeutic shoe is a feasible way to off-load and heal forefoot ulcers. A controlled trial is needed to compare the effectiveness and safety of a sealed shoe to other non-removable devices

Loading Applied To The Implant Of Transfemoral Amputees Fitted With A Direct Skeletal Fixation During Walking In A Straight Line And Around A Circle

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Loading Applied On The Abutment Of Transfemoral Amputees Fitted With An Osseointegrated Implant

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Loading applied to the implant of transfemoral amputees fitted with a direct skeletal fixation during load bearing exercises

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