Osseointegrated reconstruction and rehabilitation of transtibial amputees: the Osseointegration Group of Australia surgical technique and protocol for a prospective cohort study

IntroductionLower extremity amputation uniformly impairs a person’s vocational, social and recreational capacity. Rehabilitation in traditional socket prostheses (TSP) is associated with a spectrum of complications involving the socket-residuum interface which lead to reduced prosthetic use and quality of life. Osseointegration has recently emerged as a novel concept to overcome these complications by eliminating this interface and anchoring the prosthesis directly to bone. Though the complications of TSPs affect both transfemoral and transtibial amputees, Osseointegration has been predominantly performed in transfemoral ones assuming a greater benefit/risk ratio. However, as the safety of the procedure has been established, we intend to extend the concept to transtibial amputees and document the outcomes.Methods and analysisThis is protocol for a prospective cohort study, with patient enrolment started in 2014 and expected to be completed by 2022. The inclusion criteria are age over 18 years, unilateral, bilateral and mixed transtibial amputation and experiencing socket-related problems. All patients receive osseointegrated implants, the type of which depend on the length of the residuum and quality of bone, which are press-fitted into the residual bone. Objective functional outcomes comprising 6-Minute Walk Test, Timed Up-and-Go test and K-level, subjective patient-reported-quality-of-life outcomes (Short Form Health Survey 36, daily prosthetic wear hours, prosthetic wear satisfaction) and adverse events are recorded preoperatively and at postoperative follow-up intervals of 3, 6, 12 months and yearly, and compared with the preoperative values using appropriate statistical tests. Multivariable multilevel logistic regression will be performed with a focus to identify factors associated with outcomes and adverse events, specifically infection, periprosthetic fracture, implant fracture and aseptic loosening.Ethics and disseminationThe Ethics approval for the study has been received from the University of Notre Dame, Sydney, Australia (014153S). The outcomes of this study will be disseminated by publications in peer-reviewed academic journals and scientific presentations at relevant orthopaedic conferences.

Modeling and Evaluation of Smart Economic Transfemral Prosthetic

This study deals with evaluation of smart economic transfemral Prosthetic consist of a new design and manufacturing of knee joint and design and manufacture of a simple electronic circuit that is programmed to control the muscle pressure on the sensor during movement and transfer the voltage of force sensor after processing in microcontroller to the electric motor to flexion and extend the knee joint. A number of tests were carried out to evaluate the smart prosthetic. Gait cycle and EMG tests were performed on a patient with amputation above the knee in two cases, the first is when the patient is wearing the traditional limb and the second is when the patient is wearing the smart prosthetic. The results showed that the gait cycle during the wearing of the smart prosthetic is more acceptable, stable and balanced than the case of the traditional prosthetic wear. The results of EMG test showed that muscles need less effort during movement when wearing a smart limb and this indicates that the energy spent is less and thus provide comfort to the patient. The results of the finite element analysis (ANSYS 14.5) of the knee joint confirmed the strength of the joint and its ability to carry high weights for patients.

Rasch analysis of the Locomotor Capabilities Index-5 in people with lower limb amputation

The aim of this study was to perform a Rasch analysis on the 5-level ordinal scale version of the Locomotor Capabilities Index (LCI-5), in order to investigate rating scale quality and conduct reliability and validity assessments. A questionnaire was mailed to 144 subjects who had undergone lower limb amputation (LLA) in the previous five years and completed a rehabilitation and prosthetic training programme. A total of 123 persons (85%) responded to the questionnaire, a self-report assessment of prosthetic capability and performance which included the LCI-5, the Mobility Section of the Prosthesis Evaluation Questionnaire (PEQ-MS) and other variables associated to prosthetic wear and use. Following Rasch analysis and expert review, the LCI-5 response categories level 1 (‘yes, if someone helps me’) and 2 (‘yes, if someone is near me’) were combined into a single category and 4 items were deleted (due to misfitting). The remaining 10 items fitted the Rasch model (LCI10-4) and demonstrated good reliability (person separation reliability = 0.94, item separation reliability = 0.98) and internal construct validity. Moreover, the good correlation with the PEQ-MS (rs = 0.77) and with prosthetic wear and use (rsrange 0.34 – 0.51) supported the convergent validity of the scale. In conclusion, Rasch analysis provided the rationale for improving the measurement qualities of the LCI-5, refining its rating scale (through category diagnostics), identifying those items most useful for measuring the intended construct (as per the indexes of unidimensionality and internal construct validity) and showing that one can place high confidence in the consistency of both the person-ability and item-difficulty estimates obtained (reliability).