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PubMed1998

[First consultation with specialists for a child presenting with forelimb unilateral agenesis. Group for the Study and Research of Limb Agenesis (GERAM)].

After the birth of a child with a forelimb unilateral agenesis, the first consultation is of cardinal importance for the family. It should take place as soon as possible. The major point to be emphasized is that the child, although different, must not be considered as handicapped. If the aesthetic prejudice is evident, the functional incapacity is limited to some specific situations. In practice, the child with or without a prosthesis will have the same autonomy as children of the same age. A first prosthesis is usually proposed at 6 or 7 months of age. The child will wear the prosthesis more or less easily depending mainly upon the family attitude. It is recommended that the family have access to a medical team including a psychologist and an occupational therapist.

Arm↗

PubMedDate not supplied

Contrasts in gait mechanics of individuals with proximal femoral focal deficiency: Syme amputation versus Van Nes rotational osteotomy.

Lower-limb kinematics and kinetics during preferred and fast speeds of walking were measured in persons with proximal femoral focal deficiency to compare outcomes after Syme amputation (nine subjects) with those after Van Nes rotational osteotomy (10 subjects). Subjects with a Van Nes rotational osteotomy and full tibial rotation (seven subjects) demonstrated prosthetic knee function during stance as they were able to support a flexed-knee posture at both speeds and produced greater knee-extensor moments at preferred speeds as compared with the Syme group (p < 0.05). Nonprosthetic limb compensatory mechanics were significantly exacerbated in subjects with a Syme amputation compared with the Van Nes group: (a) stance-phase vaulting, resulting in greater inappropriate ankle-power generation at both walking speeds, (b) excessive hip-extensor moments at fast speeds, (c) excessive hip-power absorption and generation at both speeds, and (d) excessive knee-joint power generation at both speeds (p < 0.05). The improved gait after Van Nes rotational osteotomy is one factor that should be considered when making clinical decisions for children with proximal femoral focal deficiency.

Adolescent↗

PubMed1990

Research and practice with congenital amputees: making the whole greater than the sum of its parts.

This paper highlights the need for methodologically sound research on the motor, cognitive and psychosocial development of children with congenital limb deficiencies and the integration of findings in these three areas. Such topics have received little attention in the literature and systematic attempts to apply developmental theory to the assessment, fitting, training and evaluation of these children seldom have been made. A number of important current issues in research and practice are critically reviewed including optimal age for fitting, training procedures, prosthesis usage, cognitive deficits and vulnerability to psychosocial problems. Recommendations for the adoption of a more holistic approach to research and practice with amputee children are presented and the need to develop strategies for systematic evaluation and follow up is emphasized.

Abnormalities, Drug-Induced↗

PubMed2005

Relationship between energy cost, gait speed, vertical displacement of centre of body mass and efficiency of pendulum-like mechanism in unilateral amputee gait.

The energy cost of gait (C) is greater in amputee than in normal subjects. Our objective was to assess the influence of lower speed, inefficient pendulum mechanism and disturbed smoothness of centre of body mass (CM(b)) displacement on C in unilateral amputees and to have a better understanding the relationship between these variables. Twelve adult patients (six traumatic transfemoral and six vascular transtibial amputees) participated in the study. Lower limb kinematics, displacement of CM(b), mechanical work done by the muscles to move the CM(b) and the segments due to their movements relative to the CM(b), efficiency of the pendulum mechanism, and C were assessed simultaneously in the 12 amputees walking at their self-selected speed. Our results show that C depended on gait speed, and efficiency of pendulum-like mechanism of walking but did not depend on the smoothness of CM(b). The use of only a single variable to explain the extra cost in amputee gait could sometimes be misleading.

Adult↗

PubMed2000

Imaging of the painful lower limb stump.

Several postoperative complications associated with pain may develop in the stump of an amputated lower limb. Clinical findings are often nonspecific; however, radiologic evaluation, especially with magnetic resonance (MR) imaging, is useful in the early diagnosis of these complications, thereby helping minimize physical disability with its psychologic and socioeconomic implications. Conventional radiography can demonstrate evidence of osseous origins of pain (eg, aggressive bone edge, heterotopic ossification, osteomyelitis) and should be the first imaging study performed after clinical examination. Videofluoroscopy can help evaluate improper prosthetic fit by demonstrating abnormal residual limb motion, piston action, rolling of soft tissues, and abnormal angle between the limb axis and the prosthesis during gait. Ultrasonography can demonstrate inflammatory changes in the stump as well as soft-tissue fluid collections. However, MR imaging is the modality of choice when clinical and other imaging findings are indeterminate. Because of its high spatial and contrast resolution, MR imaging can demonstrate subtle inflammatory changes, fluid collections, cancers, neuromas, and subtle traumatic bone lesions. Knowledge of various surgical and rehabilitation techniques is required for accurate diagnosis of complications associated with stump pain. Correct diagnosis allows choice of the most appropriate therapy, which may involve treating the stump, remodeling the prosthesis, or both.

Amputation Stumps↗

PubMed2001

Phantom limb pain: a report of two cases.

The efficacy of pre-emptive analgesia for phantom limb pain is still unclear. It is generally accepted that pre hyphen;amputation pain increases the incidence of phantom and stump pain, even if pre-emptive analgesia is performed before and during surgery and in the postoperative period. Two cases of traumatic upper limb amputations are described here with no pre-existing pain. Both received similar antinociceptive treatment by continuous block of the brachial plexus through infusion of ropivacaine 0.375% at 5 ml/h for 10 days. Treatment of case 1 was initiated immediately after surgery; however, this amputee developed intensive phantom limb pain which persisted at 6 months. Early use of the prosthesis after surgery was not possible for this patient. The intensity of phantom limb pain in case 2 decreased significantly after 6 months, even though brachial plexus blockade was not started until 5 weeks post-trauma. This patient used a functional prosthesis intensively beginning early after amputation. Serial magnetoencephalographic recordings were performed in both patients. Only case 2 showed significant changes of cortical reorganization. In case 1 markedly less cortical plasticity was found. A combination of relevant risk factors such as a painful neuroma, behavioural and cognitive coping strategies and the early functional use of prostheses are discussed as important mechanisms contributing to the development of phantom pain and cortical reorganization.

Adult↗

PubMed1992

Design and evaluation of a sensory feedback system that provides grasping pressure in a myoelectric hand.

Providing accurate sensory information to the individual with a myoelectric limb is of great importance for improving device use in a wide variety of tasks. A number of feedback systems presently being investigated rely on either vibrotactile or electrotactile skin stimulation, which does not provide sensory patterns similar to those in a natural grasping hand. A prototype system was developed to enhance sensory information transfer by using a technique in which the feedback modality (pressure) was the same as the grasping pressure. The present study compared the developed system (pressure) with vibrotactile feedback, vision, and compounds of these three modes. It was found that the pressure-pressure concept reduced grasping pressure replication errors and error variability.

Adult↗

PubMed1989

Rotational osteotomy for proximal femoral focal deficiency.

Thirteen patients who had a proximal femoral focal deficiency and were treated with a rotational osteotomy of the tibia (Van Nes procedure) were evaluated at an average of five years after operation. Five patients needed a repeat osteotomy of the tibia: four because the limb had spontaneously derotated toward the original position and one because the limb had had insufficient rotation at the time of operation. One patient had a disarticulation at the ankle after the first stage of a planned two-stage procedure because the mother was not happy with the child's appearance. In ten limbs, the distal femoral growth plate and epiphysis were removed and in two, the femoral epiphysis and growth plate and the tibial growth plate were removed so that the joint of the prosthetic knee would be positioned at the proper height at the completion of the child's growth. Neither growth plate was removed from one limb, the shorter one in the child who had bilateral involvement. A ten-point grading scale based on use and fit of the prosthesis, gait, range of motion of the ankle, use of external support, and final height of the ankle compared with that of the contralateral knee was used to evaluate the result, which was excellent in six patients, good in four, fair in one, and poor in one. One patient, who had a disarticulation at the ankle, was excluded from the final evaluation. Rotational osteotomy provided good function and acceptable cosmetic appearance in the patients who had unilateral involvement.

Ankle Joint↗

PubMed2003

Above-the-knee amputation after a total knee replacement: prevalence, etiology, and functional outcome.

BACKGROUND: Despite modern surgical techniques, salvage of a failed total knee replacement remains a challenge. In certain situations, when other treatment options have been exhausted, patients with a failed total knee replacement may become candidates for above-the-knee amputation. The objective of this study was to assess the prevalence, etiology, and functional outcome of above-the-knee amputation performed proximal to an ipsilateral total knee replacement. METHODS: From 1970 to 2000, 18,443 primary total knee replacements were performed at our institution; sixty-seven (0.36%) were eventually followed by above-the-knee amputation. Forty-two of the amputations were performed for a cause unrelated to the total knee replacement, most commonly peripheral vascular disease (twenty-four knees). The remaining twenty-five above-the-knee amputations were performed for causes related to the total knee replacement: nineteen were done for uncontrollable infection; two, for periprosthetic fracture; two, for pain; one, for severe bone loss; and one, for a vascular complication. RESULTS: The twenty-five above-the-knee amputations performed for causes related to the total knee replacement were done at an average of 8.6 years (range, eight days to 23.6 years) after the replacement. The prevalence of above-the-knee amputations done for causes related to total knee replacement was 0.14%. Complications after the above-the-knee amputation included deep infection in five patients and superficial infection and skin necrosis in one each; there was also one perioperative death. Nine of the twenty-five limbs were fitted with an above-the-knee prosthesis, but only five patients were walking even to a limited degree with the prosthesis at the time of the last follow-up. CONCLUSIONS: The overall prevalence of amputation after total knee arthroplasty at our tertiary care center was 0.36%. The majority (63%) of the amputations were performed for reasons not attributable to complications of the arthroplasty. The functional outcome after amputation performed above a total knee replacement is poor. A substantial percentage of the patients were never fitted with a prosthesis, and those who were seldom obtained functional independence.

Aged↗

PubMed2002

[Fast automated finite element mesh generation of residual lower limb for clinical application].

Objective. To develop a model of fast automated mesh generation of residual lower limb for clinical application. Method. Actual geometry of the bone was represented as a standard pretreated model of bone, which was auto-located by employing an affine scaling transformation. Hexahedral or wedge elements were constructed by joining quadrilateral or triangular meshes generated by graph partitioning method and transport-mapping method from successive planar cross sections. Result. A model of fast automated mesh generation of residual lower limb was developed, which can be applied to different amputee and ensure the geometric integrality of bone. Auto-location of the bone was carried out. The mesh refinement can be controlled to adapt to different computational efficiency. The generated elements are hexahedral or wedge elements, both of which are more precise than tetrahedral element. Conclusion. The present method could be applied in finite element analysis method for prosthetic socket designing. Radioactive damage from those techniques such as CT or MRI to the amputee and the difficulty in image processing could be avoided.

Amputation Stumps↗

PubMed1992

Comparative biomechanical analysis of energy-storing prosthetic feet.

Gait analysis was performed on eight men who had unilateral traumatic below-knee amputation and on nine control subjects. Each subject was given two prostheses--the Seattle Foot and the Flex Foot--which differed only in the energy-storing foot component. Analysis of subjects consisted of clinical gait observation, forceplate analysis of the ground reaction force (GRF) while using each prosthesis during level walking at the natural cadence, and evaluation of subject preference between the two prosthetic feet. In the control subjects, there was no significant asymmetry in any averaged GRF patterns or parameters. In the subjects with amputations, the amputated limb had a weaker propulsion and the nonamputated limb had a stronger propulsion than controls. This was true for both prostheses. During ambulation with the Flex Foot, there was a pattern of larger late vertical forces but smaller late anteroposterior and mediolateral forces. This is consistent with a medial heel whip, and it was observed when the Flex Foot was used. Three months after the biomechanical studies, four subjects used the Flex Foot exclusively, two used the Seattle Foot exclusively, and two used both, ie, the Flex Foot for sports and the Seattle Foot for work. Application of these results to the choice of prosthetic components is discussed.

Adult↗

PubMed1997

Generic, geometric finite element analysis of the transtibial residual limb and prosthetic socket.

Finite element (FE) analysis was used to investigate the stress distribution between the residual limb and prosthetic socket of persons with transtibial amputation (TTA). The purpose of this study was to develop a tool to provide a quantitative estimate of prosthetic interface pressures to improve our understanding of residual limb/prosthetic socket biomechanics and prosthetic fit. FE models of the residual limb and prosthetic socket were created. In contrast to previous FE models of the prosthetic socket/residual limb system, these models were not based on the geometry of a particular individual, but instead were based on a generic, geometric approximation of the residual limb. These models could then be scaled for the limbs of specific individuals. The material properties of the bulk soft tissues of the residual limb were based upon local in vivo indentor studies. Significant effort was devoted toward the validation of these generic, geometric FE models; prosthetic interface pressures estimated via the FE model were compared to experimentally determined interface pressures for several persons with TTA in a variety of socket designs and static load/alignment states. The FE normal stresses were of the same order of magnitude as the measured stresses (0-200 kPa); however, significant differences in the stress distribution were observed. Although the generic, geometric FE models do not appear to accurately predict the stress distribution for specific subjects, the models have practical applications in comparative stress distribution studies.

Artificial Limbs↗

PubMed1991

Proximal femoral focal deficiency: evaluation and management.

Proximal femoral focal deficiency is a rare congenital anomaly characterized by limb malrotation, deficiency of the iliofemoral articulation, and limb length discrepancy. Advances in radiology, such as computed tomography and magnetic resonance imaging, have enhanced the assessment of pelvic-femoral instability prior to ossification of the femoral capital epiphysis. The histopathology of the fetal proximal femoral growth plate has been described, which has increased our knowledge about the etiology of the proximal femoral malformation. Data are now available regarding the long-term functional status of patients with severe acetabular dysplasia (Aitken Class C or Class D deformity) following nonoperative management of the hip. A review of the current knowledge regarding proximal femoral focal deficiency is presented to assist the orthopedic surgeon in evaluation and management.

Amputation, Surgical↗

PubMed1986

Myoelectric control of prostheses.

The development of myoelectric control systems for powered limb prostheses has advanced rapidly in recent years. The main thrusts in this development have been in realizing self-contained prostheses and in realizing better prostheses control through improvements in the myoelectric signal processing techniques. This review considers the latter of these two areas. It first presents an historical look at myoelectric signal processing and identifies the problems. It then presents a general look at the myoelectric signal and those characteristics which give rise to these problems. A review of the literature related to various control strategies and signal processing techniques to overcome these problems is given. Finally, future trends to be expected in this area are discussed.

Arm↗

PubMed1998

[Surgical management of malignant bone tumors in the child. Saint-Etienne Hospital experience, apropos of 17 cases].

From 1980 to 1997, seventeen children were treated for malignant bone tumors in the Department of Paediatric Surgery of the Saint-Etienne Hospital, with an average follow-up of 6 years and 3 months (2M-17Y). The histologic diagnoses were osteosarcomas (12 cases) and Ewing's sarcomas (5 cases). All children were treated surgically. For the 12 lower limb tumors, the techniques used were prosthetic replacement in 7 cases (associated with bone allograft in 3 cases), amputation in 3 cases and isolated bone allograft in 2 cases. The two ilium tumors were treated by resection and reconstruction with autologous bone graft. A single resection was performed for the shoulder-blade Ewing's tumors and a prosthesis for the 2 proximal humerus tumors. Six children died during follow-up. The authors stress that carcinologic resection is a priority before functional results. They insist on the mechanical failures of implants and on the difficulties of reoperations.

Adolescent↗

PubMed1992

Psychological adjustment and perceived social support in children with congenital/acquired limb deficiencies.

The negative impact on psychological adjustment from the chronic strain of living with limb deficiencies appears to be mediated by perceived social support. A multifactorial investigation was conducted to identify empirically psychological adjustment correlates of perceived social support in 49 children with congenital/acquired limb deficiencies. A multiplicity of adjustment factors (depression, trait anxiety, self-esteem) was variously related to perceived parent, teacher, classmate, and friend social support. Hierarchical multiple regression analyses provide initial evidence of the potentially powerful effects of the social environment of the school setting, with perceived classmate social support the only significant predictor variable across depressive symptomatology, trait anxiety, and general self-esteem. The results are discussed as the first step in identifying the potential correlates of multiple perceived social support domains, which may provide empirical guidance for future intervention studies designed to modify adjustment factors in chronically ill and handicapped children.

Adaptation, Psychological↗

PubMedDate not supplied

Recreational activities of lower-limb amputees with prostheses.

Ninety-two (92) persons with lower-limb amputations who regularly used prostheses responded to a survey that included questions about preferred recreational activities. This article describes the variety of activities selected by these men and women aged 20 to 87 years. Of the activities that were of high importance, 74% to 88% could be performed. Those activities assigned moderate to low importance were less often reported as able to be performed. The activities that require high energy level were more problematic for performance. The diversity of identified activities (n= 166) underscores the value of learning about amputees' activity preferences when making prosthetic prescription decisions.

Adult↗

PubMed1984

Prostheses alignment: effect on gait of persons with below-knee amputations.

This study investigated the effect on gait of changing prosthetic alignment for five people with amputations. Three-dimensional angular kinematic data were recorded by electrogoniometers positioned at their hips and knees. Indices of symmetry were developed in time and frequency domains for motion data of lower limbs when walking. These measures of symmetry were determined at different prostheses alignment settings and used to assess the possibility of aligning below-knee prostheses on the basis of symmetry of lower limb motion. Optimal or neutral alignment of below-knee prosthesis, as selected by clinically experienced personnel, tended to minimize asymmetry of gait at the hips and knees for persons with below-knee amputations. The indices of symmetry showed that alignment changes to the prosthetic foot disrupt gait to a greater extent than do other alignment changes. Asymmetries of hip flexion-extension motions were more sensitive to alignment changes than were other asymmetries. An index was selected that showed sensitivity to changes in gait caused by changes in prosthetic alignment for below-knee amputations. Refinements and other applications of this index in rehabilitation are suggested.

Artificial Limbs↗