Limb Fitting Research Articles

Patient-Perceived Disability Following Transtibial Amputation and Prosthetic Limb Fitting

ABSTRACT Introduction Patients’ perception of their disability following lower-limb amputation is currently measured using patient-reported outcomes (PROs) instruments. The validity is determined by comparing instruments designed to measure patient-perceived impact on amputation-specific health-related quality of life. The goal of this investigation was to compare patient-perceived disability from an outcomes instrument specific to individuals with amputation to a well-accepted outcomes instrument used to measure disability and response to treatment in generic musculoskeletal disease. Materials and Methods Twenty-one patients completed the Prosthesis Evaluation Questionnaire (PEQ) and the Short Musculoskeletal Functional Assessment (SMFA) at a minimum of 3 months following transtibial amputation while undergoing prosthetic limb fitting and gait training. A functional measure of their walking ability based on Medicare ambulatory function (Amputee Mobility Predictor [AMP]) was scored by a trained rehabilitation professional. Results The results of the outcomes scores provided initial evidence that the PEQ and SMFA assessments are correlated (i.e., provide some evidence of convergent validity). For every 100-point improvement in patients’ PEQ score, their SMFA Bother score declined by approximately 7 points (b = −6.94; P = 0.001) and Dysfunction score declined by approximately 7 points (b = −6.74; P < 0.001). Conversely, the SMFA and PEQ subscores were not associated with the AMP K-level (all P's > 0.05). Conclusions The findings suggested that the PEQ and SMFA PRO instruments are correlated in their ability to measure impact on health-related quality of life. Additionally, we found that PROs (PEQ and SMFA) did not predict physical ability as measured by the AMP K-level. The value of this investigation suggests that the easy-to-administer SMFA correlates well with the accepted PEQ, making testing both less cumbersome and time-consuming. Neither measure correlated with eventual ambulatory function. Rehabilitation following lower-limb amputation demands patient-specific goals. Available tools appear valuable in assisting the rehabilitation team in developing realistic objective tools for rehabilitation following lower-limb amputation. Clinical Relevance The simple-to-use SMFA appears to be comparable to the more cumbersome PEQ in assessing patient outcomes following transtibial amputations. Neither outcome instrument is correlated with functional task performance in this patient population.

Exploring the patient experience and perspectives of taking part in outcome measurement during lower limb prosthetic rehabilitation: a qualitative study

Purpose Outcome measurement provides clinicians, services and funders with useful information. However, little is known about the experience of participating in outcome measurement during lower limb prosthetic rehabilitation from the patient’s perspective. Materials and methods Thirty-two participants who underwent lower limb amputation within 5 years, and had experience of taking part in outcome measurement during prosthetic rehabilitation, were recruited from UK limb fitting centers and social media. Data were collected using focus groups and interviews and analysed using reflexive thematic analysis. Results Four themes were identified. (1) How does participating in outcome measurement make me feel? (2) Do the outcome measures used in routine clinical care capture an accurate picture of my recovery? (3) Who is outcome measurement for? and (4) are prosthetic services measuring what is meaningful? These themes suggest outcome measurement is not a neutral activity for patients following lower limb amputation. Conclusions Harnessing the positive impacts of measuring outcomes could be used for motivation, to support adjustment and recovery, to improve communication and to support shared decision-making. This could make outcome measurement more meaningful and patient-centered. However, there may be potential for patients to respond negatively to outcome measures and clinicians should consider their impact on psychosocial factors.

Knee disarticulation vs. transfemoral amputation after failed transtibial amputation: Surgical outcome and prosthetic fitting in patients with peripheral vascular disease.

Our aim was to compare transfemoral amputation (TFA) to knee disarticulation (KD) as a reamputation level after failed transtibial amputation (TTA) in patients with peripheral vascular disease and/or diabetes. We studied 152 patients undergoing reamputation, 86 TFA and 66 KD, after a failed TTA. The primary outcome was reamputation and reoperation, and secondary outcomes were prosthetic fitting and mortality. Logistic regression analyses were performed to identify factors associated with the outcome. The reamputation rate was 36% after KD and 15% after TFA ( p = 0.004). The multivariable analysis showed that TFA was associated with a significantly reduced risk of reamputation, odds ratio (OR) = 0.31 (95% confidence interval [95% CI], 0.1-0.7). The overall reoperation rate was 38% after KD and 22% after TFA ( p = 0.03). This reduction of risk for TFA was not significant in the multivariable analysis, OR = 0.49 (95% CI, 0.2-1.0). Prosthetic limb fitting was possible in 30% after KD and 19% after TFA ( p = 0.1). Previous amputation in the contralateral leg was the only factor associated with reduced ability for prosthetic fitting in the multivariable analysis, OR = 0.15 (95% CI, 0.03-0.7). Mortality at 30 d was 17% and 53% at 1 year. No independent factors affected 30-d mortality in the multivariable analysis. In this study, we found a significantly lower risk of reamputation after TFA compared with KD after a failed TTA. We consider TFA to be the reamputation level of choice, especially when there is a need of reducing risk of further reamputations.

174 Functional Outcomes in Older Patients Following Major Limb Amputation

Abstract Aim More than 5,000 major limb amputations (MLA) are performed annually in the United Kingdom. The relationship between medical co-morbidity and frailty is complex and can have an adverse effect on both mortality and functional capacity. This may be particularly important for older patients. We have attempted to define functional outcome by describing place of discharge, functional capacity and limb-fitting. Method This was a retrospective review of a prospectively collated data set on MLA performed in a single Scottish Health Board (NHS Greater Glasgow and Clyde). Older patients were defined as those over 80-years at the time of MLA. Primary outcome measures were place of discharge, functional capacity at the time of follow-up and successful limb fitting. Results There were 389 consecutive MLAs performed of which 33 were in patients over the age of 80-years. There were 3 (9.4%) inpatient deaths, and the median duration of stay was 57-days. Only 13 (43.3%) patients were discharged home to independent living. The remaining patients were discharged to either supported living or nursing home care. There were 13 (43.3%) patients who were discharged bed bound. Only 7 (21.2%) were successfully limb-fitted. At 12-months 22 (73.3%) of patients were dead. Conclusions MLA in older patients is associated with loss of function and therefore loss of independence. Most patients have died within a year of surgery. These data should help modify expectations for patients, families and clinicians and will help with the process of informed consent.

Surgical and rehabilitation outcomes of patients undergoing through knee amputation compared with above knee amputation

Background: Through knee amputation (TKA) may offer benefits over above knee amputation (AKA) in patients unsuitable for below knee amputation. This retrospective analysis compared surgical and rehabilitation outcomes post TKA and AKA. Methods: All TKA and AKA procedures recorded in the Scottish Physiotherapy Amputee Research Group dataset from January 2007 to December 2017 were included for analysis. All aetiologies, re-amputations and bilateral procedures were included. Demographic information, surgical outcomes (ie, further surgery, survival, and length of stay) and rehabilitation outcomes (ie, limb fitting, early rehabilitation, and mobility scores) were compared using descriptive and inferential statistics, including Kaplan–Meier, log-rank statistics and multivariate logistic regression. Results: In total, 4,197 procedures were included for analysis (3,471 initial AKA, 146 initial TKA, 580 initial below-knee or other level). Survival (p=0.809) and length of stay (p=0.696) were similar between groups, but TKA had significantly higher rates of further surgery (p<0.001). Multivariable analysis showed that patients who undergo TKA at centres which perform small numbers of TKA are significantly more likely to need further surgery (p=0.048). A significantly larger proportion of these patients had a limb fitted (25%) compared with only 12% of those from centres performing larger numbers of TKA (p=0.041). Overall, 31% (n=23) of those with TKA and 30% (n=725) of those with AKA had a limb fitted (p=0.854). All other rehabilitation outcomes were similar between groups. Conclusion: High volume centres have better surgical outcomes but appear to select patients not likely to limb fit. Despite this, similar proportions of patients did subsequently limb fit between groups, which may suggest superior rehabilitation potential for TKA compared with AKA, although the numbers performed in Scotland are very small. Prospective randomised studies are urgently needed to inform clinical practice.

Exploring meaningful outcome domains of recovery following lower limb amputation and prosthetic rehabilitation: the patient’s perspective

Purpose There is currently no consensus regarding what outcome domains to measure following lower limb prosthetic rehabilitation. Prosthetic users have a unique insight into important outcome domains, little is currently known about their critical viewpoint. Materials and methods A total of 37 participants who underwent lower limb amputation in the last five years were recruited from UK limb fitting centres and social media. Data were collected using focus groups and interviews and analysed using reflexive thematic analysis. Results Five themes were identified. 1) The ability to participate in important activities, 2) how participants were able to undertake these activities, i.e., independently, with ease, safely and with minimal equipment. 3) A comfortable, easy-to-use prosthesis, 4) the importance of managing pain and finally, 5) adjusting and accepting their new normal. These five themes, or outcome domains, did not exist in isolation, but appeared to interact with each other, contributing to, or inhibiting the participant’s holistic sense of recovery. Conclusions Understanding important outcome domains that define what recovery means to people following amputation can help to inform domain consensus, as well as direct the focus of rehabilitation. Domain consensus would guide the selection of measurement tools that evaluate prosthetic interventions in a meaningful way. IMPLICATIONS FOR REHABILITATION There is currently no consensus around which outcome domains should be measured following prosthetic rehabilitation. Outcome domains of importance from a patient’s perspective focus on participation in important activities, prosthesis comfort, pain management, and acceptance of their new normal. Identifying these domains can help direct the focus of rehabilitation as well as inform outcome measurement practice. The interrelated nature of these domains suggests the need for a physical and psychosocial multi-domain approach to outcome measurement in prosthetic rehabilitation, with patient priorities at its centre.

Impact of PPAM aid use on the time to prosthetic limb delivery in patients with unilateral transtibial amputation: A retrospective analysis.

The pneumatic postamputation mobility (PPAM) aid is the most commonly used early walking aid in the United Kingdom in transtibial amputation (TTA) and promotes wound healing and prepares the stump for prosthetic limb fitting. Optimal guidelines for PPAM aid use and how these factors affect achievement of rehabilitation milestones have not yet been conclusively established. To investigate the relationship between PPAM aid use and the time taken to achieve rehabilitation milestones in patients undergoing unilateral TTA. Retrospective case note analysis. Case notes of patients from one National Health Service amputation rehabilitation center who were identified as having a unilateral TTA in 2017-2018 and fitted with a prosthesis were reviewed. One hundred seven patients (67.5% male; mean age of 59.9 years) were identified. Use of PPAM aid during inpatient physiotherapy was associated with the days to reach referral, casting, delivery of prosthetic limb, and inpatient discharge dates (r (105) =-0.345; -0.400; -0.423; 0.546, respectively, all P < 0.05). Frequency of PPAM aid use was associated with the time to reach casting (r (105) =-0.533, P < 0.05) and delivery (r (105) =-0.513, P < 0.05). The days to being PPAM aid use and the frequency of PPAM aid use were predictive of the days to reach referral, casting, delivery, and inpatient discharge. The use of the PPAM aid is associated with a reduction in the time taken to reach rehabilitation milestones. Early and more frequent use of PPAM aid during rehabilitation will decrease the time fit and delivery of the prosthetic limb.

Through-knee versus above-knee amputation for vascular and non-vascular major lower limb amputations.

Diabetes and vascular disease are the leading causes of lower limb amputation. Currently, 463 million adults are living with diabetes, and 202 million with peripheral vascular disease, worldwide. When a lower limb amputation is considered, preservation of the knee in a below-knee amputation allows for superior functional recovery when compared with amputation at a higher level. When a below-knee amputation is not feasible, the most common alternative performed is an above-knee amputation. Another possible option, which is less commonly performed, is a through-knee amputation which may offer some potential functional benefits over an above-knee amputation. To assess the effects of through-knee amputation compared to above-knee amputation on clinical and rehabilitation outcomes and complication rates for all patients undergoing vascular and non-vascular major lower limb amputation. The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases; the World Health Organization International Clinical Trials Registry Platform; and the ClinicalTrials.govtrials register to 17 February 2021. We undertook reference checking, citation searching, and contact with study authors to identify additional studies. Published and unpublished randomised controlled trials (RCTs) comparing through-knee amputation and above-knee amputation were eligible for inclusion in this study. Primary outcomes were uncomplicated primary wound healing and prosthetic limb fitting. Secondary outcomes included time taken to achieve independent mobility with a prosthesis, health-related quality of life, walking speed, pain, and 30-day survival. Two review authors independently reviewed all records identified by the search. Data collection and extraction were planned in line with recommendations outlined in the Cochrane Handbook for Systematic Reviews of Interventions. We planned to assess the certainty of evidence using the GRADE approach. We did not identify RCTs that met the inclusion criteria for this review. No RCTs have been conducted to determine comparative clinical or rehabilitation outcomes of through-knee amputation and above-knee amputation, or complication rates. It is unknown whether either of these approaches offers improved outcomes for patients. RCTs are needed to guide practice and to ensure the best outcomes for this patient group.

Local injection of a hexametaphosphate formulation reduces heterotopic ossification in vivo.

Heterotopic ossification (HO), the pathological formation of ectopic bone, is a debilitating condition which can cause chronic pain, limit joint movement, and prevent prosthetic limb fitting. The prevalence of this condition has risen in the military population, due to increased survivorship following blast injuries. Current prophylaxes, which aim to target the complex upstream biological pathways, are inconsistently effective ​and have a range of side-effects that make them unsuitable for combat-injured personnel. As such, many patients must undergo further surgery to remove the formed ectopic bone. In this study, a non-toxic, U.S. Food and Drug Administration (FDA) -approved calcium chelator, hexametaphosphate (HMP), is explored as a novel treatment paradigm for this condition, which targets the chemical, rather that biological, ​bone formation pathways. This approach allows not only prevention of pathological bone formation ​but also uniquely facilitates reversal, which current drugs cannot achieve. Targeted, minimally invasive delivery is achieved by loading HMP into an injectable colloidal alginate. These formulations significantly reduce ​the length of the ectopic bone formed in a rodent model of HO, with no effect on the adjacent skeletal bone. This study demonstrates the potential of localized dissolution as a new treatment ​and an alternative to surgery ​for pathological ossification and calcification conditions.

Patient experience after lower extremity amputation for sarcoma in England: a national survey

Purpose: After amputation, rehabilitation and limb fitting services are critically important to optimise outcomes. We investigated the reported patient experience and variation in limb fitting services after amputation for musculoskeletal tumours in England.Methods: A postal survey instrument was developed following literature review, patient and clinician consultation and piloting. The survey was sent from each of the five bone tumour surgical centres in England.Results: One hundred and five responses were received from 250 patients (42%). The number of limb fitting centres accessed by each surgical centre varied from 2 to 28. Many patients reported care falling short of national standards in areas including pre-amputation counselling, information provision, meeting someone with a similar amputation before surgery, psychological support and falls management. Patients were seen sooner where limb fitting services were on site. Many patients rely on being driven, ambulance and public transport to access services.Conclusion: This study demonstrates variation in the reported experience of limb fitting services by sarcoma patients. Areas for improvement include information provision, pre-amputation counselling, psychological support and falls management. Clinicians should be aware services are highly variable, and this may impact on outcomes. Patients treated in sarcoma centres with limb fitting services on site may experience better care.Implications for RehabilitationRehabilitation services should strive to meet agreed national standards consistently.Where preamputation counselling involving meeting someone with a similar amputation is not possible, good information including video could be helpful.Services should support rehabilitation in the form of early walking aids and efficient prosthetic repair and maintenance.Psychological support, occupational therapy and physiotherapy support must be provided in the acute and chronic phases, including access to long-term rehabilitation care.Rehabilitation programmes must include training to patients and families on reporting, prevention and management of falls.On site services may support better care.Mechanisms for delivering expert specialist care close to home are needed.

The impact of gender, level of amputation and diabetes on prosthetic fit rates following major lower extremity amputation.

Background:Diabetes mellitus is a leading cause of major lower extremity amputation.Objective:To examine the influence of gender, level of amputation and diabetes mellitus status on being fit with a prosthetic limb following lower extremity amputation for peripheral arterial disease.Study design:Retrospective analysis of the Scottish Physiotherapy Amputee Research Group dataset.Results:Within the cohort with peripheral arterial disease (n = 1735), 64% were men (n = 1112) and 48% (n = 834) had diabetes mellitus. Those with diabetes mellitus were younger than those without: mean 67.5 and 71.1 years, respectively (p < 0.001). Trans-tibial amputation:trans-femoral amputation ratio was 2.33 in those with diabetes mellitus, and 0.93 in those without. A total of 41% of those with diabetes mellitus were successfully fit with a prosthetic limb compared to 38% of those without diabetes mellitus. Male gender positively predicted fitting with a prosthetic limb at both trans-tibial amputation (p = 0.001) and trans-femoral amputation (p = 0.001) levels. Bilateral amputations and increasing age were negative predictors of fitting with a prosthetic limb (p < 0.001). Diabetes mellitus negatively predicted fitting with a prosthetic limb at trans-femoral amputation level (p < 0.001). Mortality was 17% for the cohort, 22% when the amputation was at trans-femoral amputation level.Conclusion:Of those with lower extremity amputation as a result of peripheral arterial disease, those with diabetes mellitus were younger, and more had trans-tibial amputation. Although both age and amputation level are good predictors of fitting with a prosthetic limb, successful limb fit rates were no better than those without diabetes mellitus.Clinical relevanceThis is of clinical relevance to those who are involved in the decision-making process of prosthetic fitting following major amputation for dysvascular and diabetes aetiologies.

Astrometric observations of Phobos with the SRC on Mars Express

Aims. From April 2008 to August 2011 Mars Express carried out 74 Phobos flybys at distances between 669 and 5579 km. Images taken with the Super Resolution Channel (SRC) were used to determine the spacecraft-centered right ascension and declination of this Martian moon.Methods. Image positions of Phobos were measured using the limb-fit and control-point measurement techniques. Camera pointing and pointing drift were controlled by means of background star observations that were compared to corresponding positions from reference catalogs. Blurred and noisy images were restored by applying an image-based point spread function in a Richardson-Lucy deconvolution.Results. Here, we report on a set of 158 Phobos astrometric observations with estimated accuracies between 0.224 and 3.405 km circular w.r.t. the line of sight to the satellite. Control point measurements yield slightly more accurate results than the limb fit ones. Our observations are in good agreement with the current Phobos ephemerides by the Jet Propulsion Laboratory (JPL) and the Royal Observatory of Belgium (ROB) with mean offsets of up to 335 m. Our data can be used for the maintenance and update of these models.

Results of two multichord stellar occultations by dwarf planet (1) Ceres

We report the results of two multi-chord stellar occultations by the dwarf planet (1) Ceres that were observed from Brazil on 2010 August 17, and from the USA on 2013 October 25. Four positive detections were obtained for the 2010 occultation, and nine for the 2013 occultation. Elliptical models were adjusted to the observed chords to obtain Ceres' size and shape. Two limb fitting solutions were studied for each event. The first one is a nominal solution with an indeterminate polar aspect angle. The second one was constrained by the pole coordinates as given by Drummond et al. Assuming a Maclaurin spheroid, we determine an equatorial diameter of 972 $\pm$ 6 km and an apparent oblateness of 0.08 $\pm$ 0.03 as our best solution. These results are compared to all available size and shape determinations for Ceres made so far, and shall be confirmed by the NASA's Dawn space mission.

Necrotizing Soft Tissue Infections in Intravenous Drug Users: A Vascular Surgical Emergency

To assess the short and long-term outcomes of necrotizing soft tissue infection (NSTI) in intravenous drug users (IVDU) in a regional vascular centre. This was a retrospective analysis of all IVDUs with NSTI admitted to the regional vascular surgical unit between January 2009 and July 2014. Clinical outcome measures were interval between admission and surgery, length of ITU/HDU and hospital stays, post-operative complications, in hospital and one year mortality. 25 patients were admitted. The median age was 39 years (range 30-53 years) with a female to male ratio of 1:3.3. The median interval between admission and surgery was 23 hours (range 2-195 hours), however, this was significantly less when the admitting specialty was directly to vascular surgery (median 4 hours, range 2-7) compared with other specialties (median 38 hours, range 7-195 hours). Ten patients required HDU/ITU care with a median duration of 4 days (range 1-12 days). Five patients (20%) required amputation, of whom two (40%) had a prosthetic limb fitted. There was one in hospital death (4%). Another patient died while awaiting limb fitting 4 months post discharge, giving a 1 year mortality of 8%. NSTI in IVDUs carries high risk of amputation with a very low rate of limb fitting. Intervention is significantly delayed when the admitting specialty is not vascular surgery, and half of these patients require HDU/ITU care, with significant morbidity and mortality. Early diagnosis and referral to vascular surgery is crucial in management of these patients.

SIZE AND SHAPE FROM STELLAR OCCULTATION OBSERVATIONS OF THE DOUBLE JUPITER TROJAN PATROCLUS AND MENOETIUS

We present results of a stellar occultation by the Jupiter Trojan asteroid Patroclus and its nearly equal size moon, Menoetius. The geocentric mid-time of the event was 2013 October 21 06:43:02 UT. Eleven sites out of 36 successfully recorded an occultation. Seven chords across Patroclus yielded an elliptical limb fit of 124.6 by 98.2 km. There were six chords across Menoetius that yielded an elliptical limb fit of 117.2 by 93.0 km. There were three sites that got chords on both objects. At the time of the occultation we measured a separation of 664.6 km (0.247 arcsec) and a position angle for Menoetius of 2657 measured eastward from J2000 north. Combining this occultation data with previous light curve data, the axial ratios of both objects are 1.3 : 1.21 : 1, indicative of a mostly oblate ellipsoid with a slight asymmetry in its equatorial projection. The oblate shape is not an equilibrium shape for the current rotation period, but would be if it were rotating with an ~8 h period. This faster period is consistent with a pre-evolved state of the system with an orbital separation that is 50% smaller. Our best estimate of the system density is 0.88 g cm−3.

Limb fitting for quadruple amputees

We report our experiences of prosthetic fitting in quadruple amputees. Two patients underwent quadruple amputation after suffering from disseminated intravascular coagulation in conjunction with pneumococcemia with purpura fulminans. The first patient, a 52-year-old man, underwent bilateral transradial, left transtibial, and right transfemoral amputation, and the second patient, a 62-year-old man, underwent bilateral transradial and bilateral transfemoral amputation, both for symmetrical peripheral gangrene subsequent to septic shock. The amputations were accompanied by skin damage due to ischemic tissue changes both on the stumps and on the nose and/or lips. The combination of the intensive prosthetic rehabilitation program and supportive medical care led to completely independent functioning, including driving a car, with the use of four prosthetic limbs and a wheelchair in both cases. Early initiation of a multidisciplinary approach can properly address impairments and minimize future disability.

Cost Comparison

The negative impact on health-related quality of life in patients with Charcot foot has prompted operative correction of the acquired deformity. Comparative effectiveness financial models are being introduced to provide valuable information to assist clinical decision making. Seventy-six patients with Charcot foot underwent operative correction with the use of circular external fixation. Thirty-eight (50%) had osteomyelitis. A control group was created from 17 diabetic patients who successfully underwent transtibial amputation and prosthetic fitting during the same period. Cost of care during the 12 months following surgery was derived from inpatient hospitalization, placement in a rehabilitation unit or skilled nursing facility, home health care including parenteral antibiotic therapy, physical therapy, and purchase of prosthetic devices or footwear. Fifty-three of the patients with limb salvage (69.7%) did not require inpatient rehabilitation. Their average cost of care was $56,712. Fourteen of the patients with amputation (82.4%) required inpatient rehabilitation, with an average cost of $49,251. Many surgeons now favor operative correction of Charcot foot deformity. This investigation provides preliminary data on the relative cost of transtibial amputation and prosthetic limb fitting compared with limb salvage. The use of comparative effectiveness models such as this simple attempt may provide valuable information in planning resource allocation for similar complex groups of patients. Level III, economic and decision analysis.

An interfacial stress sensor for biomechanical applications

This paper presents a capacitive sensor that measures interfacial forces in prostheses and is promising for other biomedical applications. These sensors can be integrated into prosthetic devices to measure both normal and shear stress simultaneously, allowing for the study of prosthetic limb fit, and ultimately for the ability to better adapt prosthetics to individual users. A sensing cell with a 1.0 cm2 spatial resolution and a measurement range of 0–220 kPa of shear and 0–2 MPa of pressure was constructed. The cell was load tested and found to be capable of isolating the applied shear and pressure forces. This paper discusses the construction of the prototype, the mechanical and electrode design, fabrication and characterization. The work presented is aimed at creating a class of adaptive prosthetic interfaces using a capacitive sensor.

Memory and executive function predict mobility rehabilitation outcome after lower-limb amputation

Purpose. Post-amputation rehabilitation is physically and cognitively demanding. Understanding which specific cognitive domains mediate outcome is critical to the development of interventions.Method. A cohort undergoing post-amputation rehabilitation was assessed before limb fitting and followed up at 6 months (n = 34). The average age was 60.69 years (SD = 13.98). 82.4% of the sample was male. 79.4% had amputations because of peripheral arterial disease. Memory, visuospatial function, executive function, praxis, emotion and language were assessed at Time 1 (first prosthetic clinic attendance). Time 1 data were also gathered on aetiology, level of amputation, comorbidities, pain and demographics. Six month outcomes were the locomotor capability index (LCI), the special interest group in amputee medicine (SIGAM) mobility grades and self reported hours of use.Results. The LCI at 6 months was significantly predicted in regression analyses by a measure of visual memory (figure recall) (adjusted R2 = 24.8%, df = 32, zβ = 0.52, p = 0.002. Hours of use were predicted by the verbal fluency test total (adjusted R2 = 17.1%, df = 26, zβ = 0.45, p = 0.017). SIGAM mobility grades were predicted by a combination of immediate verbal memory (story recall), age, level of amputation and presence of pain (adjusted R2 = 58.2, df = 30, zβ = 0.52, p = 0.000).Conclusions. Neuropsychological and clinical variables predict a large amount of 6 month outcome variance. Cognitive difficulties may be considered mediators of poor outcome.

New astrometric observations of Phobos with the SRC on Mars Express

Aims. From April 2008 to August 2011 Mars Express carried out 74 Phobos flybys at distances between 669 and 5579 km. Images taken with the Super Resolution Channel (SRC) were used to determine the spacecraft-centered right ascension and declination of this Martian moon. Methods. Image positions of Phobos were measured using the limb-fit and control-point measurement techniques. Camera pointing and pointing drift were controlled by means of background star observations that were compared to corresponding positions from reference catalogs. Blurred and noisy images were restored by applying an image-based point spread function in a Richardson-Lucy deconvolution. Results. Here, we report on a set of 158 Phobos astrometric observations with estimated accuracies between 0.224 and 3.405 km circular w.r.t. the line of sight to the satellite. Control point measurements yield slightly more accurate results than the limb fit ones. Our observations are in good agreement with the current Phobos ephemerides by the Jet Propulsion Laboratory (JPL) and the Royal Observatory of Belgium (ROB) with mean offsets of up to 335 m. Our data can be used for the maintenance and update of these models.