The gait profile score characterises walking performance impairments in young stroke survivors.

BACKGROUND: The Gait Profile Score (GPS) provides a composite measure of the quality of joint movement during walking, but the relationship between this measure and metabolic cost, temporal (e.g. walking speed) and spatial (e.g. stride length) parameters in stroke survivors has not been reported. RESEARCH QUESTION: The aims of this study were to compare the GPS (paretic, non-paretic, and overall score) of young stroke survivors to the healthy able-bodied control and determine the relationship between the GPS and metabolic cost, temporal (walking speed, stance time asymmetry) and spatial (stride length, stride width, step length asymmetry) parameters in young stroke survivors to understand whether the quality of walking affects walking performance in stroke survivors. METHODS: Thirty-nine young stroke survivors aged between 18 and 65years and 15 healthy age-matched able-bodied controls were recruited from six hospital sites in Wales, UK. Joint range of motion at the pelvis, hip, knee and ankle, and temporal and spatial parameters were measured during walking on level ground at self-selected speed with calculation of the Gait Variable Score and then the GPS. RESULTS: GPS for the paretic leg (9.40° (8.60-10.21) p < 0.001), non-paretic leg (11.42° (10.20-12.63) p < 0.001) and overall score (11.18° (10.26-12.09) p < 0.001)) for stroke survivors were significantly higher than the control (4.25° (3.40-5.10), 5.92° (5.11 (6.73)). All parameters with the exception of step length symmetry ratio correlated moderate to highly with the GPS for the paretic, non-paretic, and/or overall score (ρ = <-0.732 (p < 0.001)). SIGNIFICANCE: The quality of joint movement during walking measured via the GPS is directly related to the speed and efficiency of walking, temporal (stance time symmetry) and spatial (stride length, stride width) parameters in young stroke survivors.

Higher knee contact forces might underlie increased osteoarthritis rates in high functioning amputees: A pilot study.

High functioning military transtibial amputees (TTAs) with well-fitted state of the art prosthetics have gait that is indistinguishable from healthy individuals, yet they are more likely to develop knee osteoarthritis (OA) of their intact limbs. This contrasts with the information at the knees of the amputated limbs that have been shown to be at a significantly reduced risk of pain and OA. The hypothesis of this study is that biomechanics can explain the difference in knee OA risk. Eleven military unilateral TTAs and eleven matched healthy controls underwent gait analysis. Muscle forces and joint contact forces at the knee were quantified using musculoskeletal modeling, validated using electromyography measurements. Peak knee contact forces for the intact limbs on both the medial and lateral compartments were significantly greater than the healthy controls (P ≤ .006). Additionally, the intact limbs had greater peak semimembranosus (P = .001) and gastrocnemius (P ≤ .001) muscle forces compared to the controls. This study has for the first time provided robust evidence of increased force on the non-affected knees of high functioning TTAs that supports the mechanically based hypothesis to explain the documented higher risk of knee OA in this patient group. The results suggest several protentional strategies to mitigate knee OA of the intact limbs, which may include the improvements of the prosthetic foot control, socket design, and strengthening of the amputated muscles.

Can high-functioning amputees with state-of-the-art prosthetics walk normally? A kinematic and dynamic study of 40 individuals.

BACKGROUND: Previous work has highlighted the highly functional post-rehabilitation level of military individuals who sustained traumatic amputation. Understanding how these individuals walk with their prosthesis could be key to setting a precedent for what is realistically possible in the rehabilitation of individuals with amputations. OBJECTIVE: The aim of this paper is to answer how "normal" should the gait of an individual with an amputation(s) be and can we aspire to mimic able-bodied gait with the most advanced prosthetics in highly functioning individuals? METHODS: This was a cross-sectional study comparing the gait of severely injured and highly functional UK trans-tibial (n=10), trans-femoral (n=10) and bilateral trans-femoral (n=10) military amputees after completion of their rehabilitation programme to that of able-bodied controls (n=10). Joint kinematics and kinetics of the pelvis, hip, knee and ankle were measured with 3-D gait analysis during 5min of walking on level ground at a self-selected speed. Peak angle, moment or range of motion of intact and prosthetic limbs were compared to control values. RESULTS: Joint kinematics of unilateral trans-tibial amputees was similar to that of controls. Individuals with a trans-femoral amputation walked with a more anterior tilted pelvis (P=0.006), with reduced range of pelvic obliquity (P=0.0023) and ankle plantarflexion (P<0.001) than controls. Across all amputee groups, hip joint moments and power were greater and knee and ankle joint moments were less than for controls. CONCLUSIONS: This is the first study to provide a comprehensive description of gait patterns of unilateral trans-tibial, trans-femoral and bilateral trans-femoral amputees as compared with healthy able-bodied individuals. The groups differed in joint kinematics and kinetics, but these can be expected in part because of limitations in prosthesis and socket designs. The results from this study could be considered benchmark data for healthcare professionals to compare gait patterns of other individuals with amputation who experienced similar injuries and rehabilitation services.

Return to Employment After Stroke in Young Adults: How Important Is the Speed and Energy Cost of Walking?

Background and Purpose- A quarter of individuals who experience a stroke are under the age of 65 years (defined as young adults), and up to 44% will be unable to return to work poststroke, predominantly because of walking difficulties. No research study has comprehensively analyzed walking performance in young adult's poststroke. The primary aim of this study is to investigate how a stroke in young adults affects walking performance (eg, walking speed and metabolic cost) compared with healthy age-matched controls. The secondary aim is to determine the predictive ability of walking performance parameters for return to employment poststroke. Methods- Forty-six individuals (18-40 years: n=6, 41-54 years: n=21, 55-65 years: n=19) who have had a stroke and 15 healthy age-matched able-bodied controls were recruited from 6 hospital sites in Wales, United Kingdom. Type, location, cause of stroke, and demographic factors (eg, employment status) were recorded. Temporal and spatial walking parameters were measured using 3-dimensional gait analysis. Metabolic energy expenditure and metabolic cost of walking were captured during 3 minutes of walking at self-selected speed from measurements of oxygen consumption. Results- Stroke participants walked slower (P<0.004) and less efficiently (P<0.002) than the controls. Only 23% of stroke participants returned to employment poststroke. Walking speed was the strongest predictor (sensitivity, 0.90; specificity, 0.82) for return to work (P=0.004) with a threshold of 0.93 m/s identified: individuals able to walk faster than 0.93 m/s were significantly more likely to return to work poststroke than those who walked slower than this threshold. Conclusions- This study is the first to capture walking performance parameters of young adults who have had a stroke and identifies slower and less efficient walking. Walking speed emerged as the strongest predictor for return to employment. It is recommended that walking speed be used as a simple but sensitive clinical indicator of functional performance to guide rehabilitation and inform readiness for return to work poststroke.

Challenging the foundations of the clinical model of foot function: further evidence that the root model assessments fail to appropriately classify foot function.

BACKGROUND: The Root model of normal and abnormal foot function remains the basis for clinical foot orthotic practice globally. Our aim was to investigate the relationship between foot deformities and kinematic compensations that are the foundations of the model. METHODS: A convenience sample of 140 were screened and 100 symptom free participants aged 18-45 years were invited to participate. The static biomechanical assessment described by the Root model was used to identify five foot deformities. A 6 segment foot model was used to measure foot kinematics during gait. Statistical tests compared foot kinematics between feet with and without foot deformities and correlated the degree of deformity with any compensatory motions. RESULTS: None of the deformities proposed by the Root model were associated with distinct differences in foot kinematics during gait when compared to those without deformities or each other. Static and dynamic parameters were not correlated. CONCLUSIONS: Taken as part of a wider body of evidence, the results of this study have profound implications for clinical foot health practice. We believe that the assessment protocol advocated by the Root model is no longer a suitable basis for professional practice. We recommend that clinicians stop using sub-talar neutral position during clinical assessments and stop assessing the non-weight bearing range of ankle dorsiflexion, first ray position and forefoot alignments and movement as a means of defining the associated foot deformities. The results question the relevance of the Root assessments in the prescription of foot orthoses.

Temporal Spatial and Metabolic Measures of Walking in Highly Functional Individuals With Lower Limb Amputations.

OBJECTIVE: To record the temporal spatial parameters and metabolic energy expenditure during walking of individuals with amputation, walking with advanced prostheses, and after completion of comprehensive rehabilitation compared with able-bodied persons. DESIGN: Cross-sectional. SETTING: Multidisciplinary comprehensive rehabilitation center. PARTICIPANTS: Severely injured UK military personnel with amputation and subsequent completion of their rehabilitation program (n=30; unilateral transtibial: n=10, unilateral transfemoral: n=10, and bilateral transfemoral: n=10) were compared with able-bodied persons (n=10) with similar age, height, and mass (P>.537). Total number of participants (N = 40). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Temporal spatial and metabolic energy expenditure data were captured during walking on level ground at a self-selected speed. RESULTS: The individuals with amputation were all men, with a mean age of 29±4 years and a mean New Injury Severity Score of 31±16. Walking speed, stride length, step length, and cadence of individuals with a unilateral transtibial or transfemoral amputation were comparable with able-bodied persons, and only individuals with a bilateral transfemoral amputation had a significantly slower walking speed (1.12m/s, P=.025) and reduced cadence (96 steps per minute, P=.026). Oxygen cost for individuals with a unilateral transtibial amputation (0.15mL/kg/m) was the same as for able-bodied persons (0.15mL/kg/m) and significantly increased by 20% (0.18mL/kg/m, P=.023) for unilateral transfemoral amputation and by 60% (0.24mL/kg/m, P<.001) for bilateral transfemoral individuals with amputation. CONCLUSIONS: The scientific literature reports a wide range of gait and metabolic energy expenditure across individuals with amputation. The results of this study indicate that individuals with amputation have a gait pattern which is highly functional and efficient. This is comparable with a small number of studies reporting similar outcomes for individuals with a unilateral transtibial amputation, but the results from this study are better than those on individuals with transfemoral amputations reported elsewhere, despite comparison with populations wearing similar prosthetic componentry. Those studies that do report similar outcomes have included individuals who have been provided with a comprehensive rehabilitation program. This suggests that such a program may be as important as, or even more important than, prosthetic component selection in improving metabolic energy expenditure. The data are made available as a benchmark for what is achievable in the rehabilitation of some individuals with amputations, but agreeably may not be possible for all amputees to achieve.

Movement of the human foot in 100 pain free individuals aged 18-45: implications for understanding normal foot function.

BACKGROUND: Understanding motion in the normal healthy foot is a prerequisite for understanding the effects of pathology and thereafter setting targets for interventions. Quality foot kinematic data from healthy feet will also assist the development of high quality and research based clinical models of foot biomechanics. To address gaps in the current literature we aimed to describe 3D foot kinematics using a 5 segment foot model in a population of 100 pain free individuals. METHODS: Kinematics of the leg, calcaneus, midfoot, medial and lateral forefoot and hallux were measured in 100 self reported healthy and pain free individuals during walking. Descriptive statistics were used to characterise foot movements. Contributions from different foot segments to the total motion in each plane were also derived to explore functional roles of different parts of the foot. RESULTS: Foot segments demonstrated greatest motion in the sagittal plane, but large ranges of movement in all planes. All foot segments demonstrated movement throughout gait, though least motion was observed between the midfoot and calcaneus. There was inconsistent evidence of movement coupling between joints. There were clear differences in motion data compared to foot segment models reported in the literature. CONCLUSIONS: The data reveal the foot is a multiarticular structure, movements are complex, show incomplete evidence of coupling, and vary person to person. The data provide a useful reference data set against which future experimental data can be compared and may provide the basis for conceptual models of foot function based on data rather than anecdotal observations.

Inter-assessor reliability of practice based biomechanical assessment of the foot and ankle.

BACKGROUND: There is no consensus on which protocols should be used to assess foot and lower limb biomechanics in clinical practice. The reliability of many assessments has been questioned by previous research. The aim of this investigation was to (i) identify (through consensus) what biomechanical examinations are used in clinical practice and (ii) evaluate the inter-assessor reliability of some of these examinations. METHODS: Part1: Using a modified Delphi technique 12 podiatrists derived consensus on the biomechanical examinations used in clinical practice. Part 2: Eleven podiatrists assessed 6 participants using a subset of the assessment protocol derived in Part 1. Examinations were compared between assessors. RESULTS: Clinicians choose to estimate rather than quantitatively measure foot position and motion. Poor inter-assessor reliability was recorded for all examinations. Intra-class correlation coefficient values (ICC) for relaxed calcaneal stance position were less than 0.23 and were less than 0.14 for neutral calcaneal stance position. For the examination of ankle joint dorsiflexion, ICC values suggest moderate reliability (less than 0.61). The results of a random effects ANOVA highlight that participant (up to 5.7°), assessor (up to 5.8°) and random (up to 5.7°) error all contribute to the total error (up to 9.5° for relaxed calcaneal stance position, up to 10.7° for the examination of ankle joint dorsiflexion). Kappa Fleiss values for categorisation of first ray position and mobility were less than 0.05 and for limb length assessment less than 0.02, indicating slight agreement. CONCLUSION: Static biomechanical assessment of the foot, leg and lower limb is an important protocol in clinical practice, but the key examinations used to make inferences about dynamic foot function and to determine orthotic prescription are unreliable.